tag:theconversation.com,2011:/global/topics/anaesthetics-7616/articlesAnaesthetics – The Conversation2023-03-01T03:55:01Ztag:theconversation.com,2011:article/2008952023-03-01T03:55:01Z2023-03-01T03:55:01ZWhy cough medicines containing pholcodine can be deadly even if you took them months before surgery<figure><img src="https://images.theconversation.com/files/512779/original/file-20230301-18-joknpv.jpg?ixlib=rb-1.1.0&rect=4%2C0%2C994%2C667&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/healthcare-people-medicine-concept-woman-pouring-512853772">Shutterstock</a></span></figcaption></figure><p>Cough medicines containing the active ingredient pholcodine are being withdrawn from sale due to safety concerns highlighted for years both in Australia and internationally.</p>
<p>Yesterday, Australia’s medicines regulator <a href="https://www.tga.gov.au/news/media-releases/pholcodine-cough-medicines-cancelled-tga-and-recalled-pharmacies-safety-reasons">announced</a> the immediate registration cancellation and recall of dozens of these over-the-counter cough medicines and lozenges.</p>
<p>This is because of the risk of a sudden, severe and life-threatening allergic reaction if people are also given specific muscle relaxant drugs while under a general anaesthetic.</p>
<p>That risk of anaphylaxis can remain weeks and months after taking the cough medicine.</p>
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<h2>What is pholcodine?</h2>
<p>Pholcodine (pronounced pho-co-dean) is an opioid-based medicine, which means it’s related to morphine and codeine. It works by binding to various opioid receptors in a part of the brain responsible for triggering the cough reflex.</p>
<p>As such, it is a common ingredient in many over-the-counter medicines used to treat a <a href="https://www.healthdirect.gov.au/cough">dry cough</a>. These include cough syrups and lozenges. Every product that contains pholcodine will list it prominently on the bottle or cardboard packaging. </p>
<p>Common brands that contain this ingredient include Benadryl, Bisolvon, Codral, Difflam, Difflam Plus and Duro-Tuss.</p>
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<h2>Why the recall?</h2>
<p>The most common side effects of pholcodine are dizziness, nausea and sedation. But the Therapeutic Goods Administration (TGA) has recalled products containing it, as pholcodine can trigger anaphylaxis around the time of surgery.</p>
<p>The issue arises when pholcodine medicines are combined with types of muscle relaxants given during surgery known as <a href="https://www.cec.health.nsw.gov.au/keep-patients-safe/medication-safety/high-risk-medicines/neuromuscular-blocking-agents">neuromuscular blocking agents</a>.</p>
<p>This type of anaphylaxis can occur in people who have had a muscle relaxant before and been previously fine, or in people who receive a muscle relaxant drug for the first time.</p>
<p>Being <a href="https://www.sciencedirect.com/science/article/pii/S0007091220310072?via%3Dihub">obese</a> also places people at higher risk of this type of anaphylaxis.</p>
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<a href="https://images.theconversation.com/files/512777/original/file-20230301-3384-mk2uiz.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Person under anesthesia during surgery, gas mask over face" src="https://images.theconversation.com/files/512777/original/file-20230301-3384-mk2uiz.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/512777/original/file-20230301-3384-mk2uiz.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=401&fit=crop&dpr=1 600w, https://images.theconversation.com/files/512777/original/file-20230301-3384-mk2uiz.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=401&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/512777/original/file-20230301-3384-mk2uiz.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=401&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/512777/original/file-20230301-3384-mk2uiz.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=504&fit=crop&dpr=1 754w, https://images.theconversation.com/files/512777/original/file-20230301-3384-mk2uiz.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=504&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/512777/original/file-20230301-3384-mk2uiz.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=504&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
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<span class="caption">Muscle relaxants given during surgery plus pholcodine can be a lethal mix.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/necessary-procedure-close-young-patient-lying-1220709154">Shutterstock</a></span>
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Read more:
<a href="https://theconversation.com/cough-syrup-can-harm-children-experts-warn-of-contamination-risks-199795">Cough syrup can harm children: experts warn of contamination risks</a>
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<h2>We’ve known about the risk for years</h2>
<p>We have actually known about the risks of pholcodine and muscle relaxants for some time, including in <a href="https://onlinelibrary.wiley.com/doi/10.1111/j.1399-6576.2004.00591.x">Scandinavian studies</a> in 2005.</p>
<p>In fact, it was because of these studies that pholcodine was withdrawn from the market in Norway <a href="https://onlinelibrary.wiley.com/doi/10.1111/j.1398-9995.2010.02518.x">in 2007</a>.</p>
<p>The European Medicines Agency recommended <a href="https://www.ema.europa.eu/en/news/ema-recommends-withdrawal-pholcodine-medicines-eu-market">the withdrawal of pholcodine</a> in Europe in December 2022.</p>
<p>In Australia, the <a href="https://www.psnetwork.org/ban-pholcodine/">PatientSafe Network</a> has been calling for its ban since at least 2017. </p>
<p>Over the past 12 months, there were nine reported cases of serious adverse effects to pholcodine reported to the TGA, including three deaths. The most recent case was in January this year. In three of the nine, pholcodine was the only suspected medicine involved. </p>
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<a href="https://images.theconversation.com/files/512764/original/file-20230228-2348-2al141.jpg?ixlib=rb-1.1.0&rect=72%2C591%2C3959%2C2323&q=45&auto=format&w=1000&fit=clip"><img alt="Some common products affected by the recall" src="https://images.theconversation.com/files/512764/original/file-20230228-2348-2al141.jpg?ixlib=rb-1.1.0&rect=72%2C591%2C3959%2C2323&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/512764/original/file-20230228-2348-2al141.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/512764/original/file-20230228-2348-2al141.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/512764/original/file-20230228-2348-2al141.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/512764/original/file-20230228-2348-2al141.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/512764/original/file-20230228-2348-2al141.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/512764/original/file-20230228-2348-2al141.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=566&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
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<span class="caption">These common cough syrups and lozenges are among products being recalled.</span>
<span class="attribution"><span class="license">Author provided</span></span>
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<h2>Why now?</h2>
<p>The TGA’s decision may come from a recent (but not yet peer reviewed) French <a href="https://www.medrxiv.org/content/10.1101/2022.12.12.22283353v1.full">study</a>. This found that when patients had taken pholcodine at any time in the 12 months before surgery that used a muscle relaxant, they were at much higher risk of anaphylaxis.</p>
<p>The French research is consistent with an earlier <a href="https://www.sciencedirect.com/science/article/pii/S0007091220310072?via%3Dihub">Western Australian study</a> which found anaphylaxis is 14 times more likely to occur when the two types of drugs are combined.</p>
<p>This is because pholcodine can linger in the body for long periods. After you swallow the medicine, the drug reaches its highest concentration in the blood stream <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1386567/">one to two hours later</a>. But both the drug and its metabolites can still be detected in the body <a href="https://www.medsafe.govt.nz/committees/marc/reports/180-3.2.1-Pholcodine.pdf">up to seven weeks later</a>.</p>
<h2>I have some at home. What now?</h2>
<p>As pholcodine can linger in the body, the TGA has warned that if you have taken a medicine containing pholcodine in the past 12 months you need to tell your doctor before you have surgery.</p>
<p>If you are taking one of these medicines you should stop immediately, even if you don’t think you’re going to have a medical procedure soon. </p>
<p>Take it to your local pharmacy for disposal. At that time, the pharmacist will be able to recommend a <a href="https://theconversation.com/health-check-do-cough-medicines-work-62425">different medicine</a> for your cough.</p>
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Read more:
<a href="https://theconversation.com/health-check-do-cough-medicines-work-62425">Health Check: do cough medicines work?</a>
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<img src="https://counter.theconversation.com/content/200895/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Associate Professor Wheate in the past has received funding from the ACT Cancer Council, Tenovus Scotland, Medical Research Scotland, Scottish Crucible, and the Scottish Universities Life Sciences Alliance. He is a Fellow of the Royal Australian Chemical Institute, a member of the Australasian Pharmaceutical Science Association, and a member of the Australian Institute of Company Directors. Nial is the chief scientific officer of Vairea Skincare LLC, a director of SetDose Pty Ltd a medical device company, and a Standards Australia panel member for sunscreen agents.</span></em></p><p class="fine-print"><em><span>Associate Professor Tina Hinton has previously received funding from the Schizophrenia Research Institute (formerly Neuroscience Institute of Schizophrenia and Allied Disorders). She is currently a Board member of the Australasian Society of Clinical and Experimental Pharmacologists and Toxicologists.</span></em></p>The risk of a severe allergic reaction when pholcodine is combined with common medicines used in anaesthesia has lead to their recall in Australia.Nial Wheate, Associate Professor of the Sydney Pharmacy School, University of SydneyTina Hinton, Associate Professor of Pharmacology, University of SydneyLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1595412021-04-27T02:12:09Z2021-04-27T02:12:09ZHow lobed brain corals are helping solve the mystery of what general anaesthesia does to the brain<figure><img src="https://images.theconversation.com/files/397243/original/file-20210427-15-x9c6hz.jpg?ixlib=rb-1.1.0&rect=0%2C5%2C3872%2C2544&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><span class="source">Shutterstock</span></span></figcaption></figure><p>Many of us will undergo general anaesthesia at some point in our lives — losing consciousness so we can be operated on painlessly. But although humans have used general anaesthesia for <a href="https://asa.org.au/history-of-anaesthesia/">more than 150 years</a>, we still don’t fully understand how it affects the brain. </p>
<p>To find out, we turned to a genus of stony coral called lobed brain coral (<em>Lobophyllia</em>). Using a unique fluorescent molecule present in lobed brain coral, we managed to isolate an important target of general anaesthetic drugs in fruit fly brains. Our <a href="https://www.eneuro.org/content/early/2021/04/14/ENEURO.0057-21.2021">findings</a> could help develop safer anaesthesia for humans. </p>
<h2>Glow-in-the-dark coral</h2>
<p>Lobed brain corals are bioluminescent, which means they can naturally produce and emit light. They’re found in the Indian and Pacific oceans, alongside other similar scientifically valuable creatures such as the crystal jelly <em>Aequorea victoria</em>. </p>
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<img alt="Crystal jelly Aequorea victoria" src="https://images.theconversation.com/files/396914/original/file-20210424-17-17sml4i.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/396914/original/file-20210424-17-17sml4i.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=900&fit=crop&dpr=1 600w, https://images.theconversation.com/files/396914/original/file-20210424-17-17sml4i.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=900&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/396914/original/file-20210424-17-17sml4i.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=900&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/396914/original/file-20210424-17-17sml4i.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1131&fit=crop&dpr=1 754w, https://images.theconversation.com/files/396914/original/file-20210424-17-17sml4i.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1131&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/396914/original/file-20210424-17-17sml4i.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1131&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
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<span class="caption"><em>Aequorea victoria</em> is a bioluminescent jellyfish found in the Pacific Ocean.</span>
<span class="attribution"><span class="source">Shutterstock</span></span>
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<p>Bioluminescent ocean-dwellers have equipped researchers with a powerful toolkit of fluorescent molecules to study and track biological processes. They even inspired the Nobel Prize-winning discovery of the <a href="https://www.nobelprize.org/uploads/2018/06/advanced-chemistryprize2008.pdf">green fluorescent protein</a>.</p>
<p>The fluorescent molecule found in the lobed brain coral, <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC528746/">Eos</a>, has a rather surprising feature: it can change colour. This lets scientists observe <a href="https://cdn.theconversation.com/static_files/files/1543/Dish4_Cell1_16000_Frames-file002-1.gif?1619331216">the movement of proteins</a> within living cells — something that was previously impossible.</p>
<p>Imagine you have a Christmas tree covered with lights but they were all lit the same colour; the tree might appear a bit blurry from afar. If one of the lights were to switch to a different colour, however, you’d spot it easily. </p>
<p>The same principles apply when scientists try to track moving proteins in cells. Proteins perform multiple vital tasks for a cell and tracking them can help us understand their function, but they’re usually too small to see with regular microscopes. </p>
<p>Using the Eos molecule, we can develop super-resolution microscopes that reveal even the smallest elements within cells, including proteins. </p>
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<a href="https://images.theconversation.com/files/397244/original/file-20210427-17-1icpgbs.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/397244/original/file-20210427-17-1icpgbs.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/397244/original/file-20210427-17-1icpgbs.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/397244/original/file-20210427-17-1icpgbs.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/397244/original/file-20210427-17-1icpgbs.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/397244/original/file-20210427-17-1icpgbs.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/397244/original/file-20210427-17-1icpgbs.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/397244/original/file-20210427-17-1icpgbs.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
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<span class="caption">A multicoloured lobed brain coral (<em>Lobophyllia</em>) with yellow tips.</span>
<span class="attribution"><span class="source">Shutterstock</span></span>
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<h2>A sleeping brain isn’t ‘inactive’</h2>
<p>Anaesthesia today generally involves injecting a patient’s vein with a dose of a sedative drug and painkiller. For instance, the combination of <a href="https://academic.oup.com/bjaed/article/16/8/276/2364847">propofol and fentanyl</a> will make you unconscious and prevent you from feeling pain.</p>
<p>Sedative drugs, including sleeping pills, use your brain’s natural ability to <a href="https://pubmed.ncbi.nlm.nih.gov/33857967/">put you to sleep</a>. They target the circuits in your brain that regulate wakefulness and stop them from being active. </p>
<p>However, the brain activity of a sleeping person is very different to that of someone under anaesthesia. A sleeping brain performs many tasks and is quite active. A brain under anaesthesia is <a href="https://pubmed.ncbi.nlm.nih.gov/29121293/">largely unresponsive</a>.</p>
<p>Why aren’t we able to be woken up while under general anaesthesia? To find out, scientists need to identify what else in the brain, apart from sleep pathways, is targeted by general anaesthetic drugs.</p>
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Read more:
<a href="https://theconversation.com/why-our-brain-needs-sleep-and-what-happens-if-we-dont-get-enough-of-it-83145">Why our brain needs sleep, and what happens if we don’t get enough of it</a>
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<h2>Anaesthesia stunts the brain’s processing power</h2>
<p>Neurons, the cells in the brain, communicate with each other through a process known as synaptic neurotransmission. This is the main way our brains process information.</p>
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<img alt="Synapse neurotransmitter release" src="https://images.theconversation.com/files/396902/original/file-20210424-17-jjukoj.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/396902/original/file-20210424-17-jjukoj.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/396902/original/file-20210424-17-jjukoj.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/396902/original/file-20210424-17-jjukoj.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/396902/original/file-20210424-17-jjukoj.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/396902/original/file-20210424-17-jjukoj.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/396902/original/file-20210424-17-jjukoj.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
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<span class="caption">Neurotransmission lets neurons to talk to one another and process information such as pain.</span>
<span class="attribution"><span class="source">Shutterstock</span></span>
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</figure>
<p>For neurotransmission to occur, specialised proteins within neurons must release chemicals called neurotransmitters (such as dopamine or glutamate). Proteins are dynamic. They can move freely inside neurons and are often needed in different parts of the cell. </p>
<p>For our research, we <a href="https://doi.org/10.1523/ENEURO.0057-21.2021">took the Eos molecule</a> and attached it onto a protein called “syntaxin1A” — which is responsible for facilitating neurotransmission — to see how general anaesthetic drugs might affect its normal function in the brains of fruit flies.</p>
<p>We found syntaxin1A dynamics were altered with general anaesthetic drugs such as propofol and isoflurane. The protein became <a href="https://pubmed.ncbi.nlm.nih.gov/29320738/">trapped in clusters of proteins</a> and its movement was therefore restricted.</p>
<p>This may have been what reduced the efficiency of neurotransmission, preventing the brain from processing complex information. </p>
<hr>
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Read more:
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<h2>A goal to develop new, safer drugs</h2>
<p>Many proteins apart from syntaxin1A are involved in neurotransmission. So it’s likely others are also affected by anaesthetic drugs. </p>
<p>This new way to observe individual protein behaviour in intact brain tissue will hopefully uncover more drug targets and explain the precise mechanisms that underpin general anaesthetics.</p>
<p>Consequently, this knowledge will aid in the development of safer drugs with fewer <a href="https://www.mayoclinic.org/tests-procedures/anesthesia/about/pac-20384568">side effects</a>. And targeted drug development could help prevent the <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4864680/">abnormally long recovery times</a> observed in some patients who undergo general anaesthesia.</p>
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<img alt="" src="https://images.theconversation.com/files/396904/original/file-20210424-13-1yka7pm.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/396904/original/file-20210424-13-1yka7pm.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=451&fit=crop&dpr=1 600w, https://images.theconversation.com/files/396904/original/file-20210424-13-1yka7pm.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=451&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/396904/original/file-20210424-13-1yka7pm.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=451&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/396904/original/file-20210424-13-1yka7pm.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=567&fit=crop&dpr=1 754w, https://images.theconversation.com/files/396904/original/file-20210424-13-1yka7pm.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=567&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/396904/original/file-20210424-13-1yka7pm.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=567&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
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<span class="caption">Anaesthetic drug development will be enhanced once we better understand how these drugs affect us.</span>
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</figure><img src="https://counter.theconversation.com/content/159541/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Bruno van Swinderen receives funding from the National Health and Medical Research Council (NHMRC)</span></em></p><p class="fine-print"><em><span>Adam David Hines does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>Scientists still still don’t fully understand how general anaesthesia affects the brain and body. A molecule found in bioluminescent stony coral may shed some light.Adam David Hines, PhD Candidate, The University of QueenslandBruno van Swinderen, Professor, The University of QueenslandLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1117272019-02-16T03:01:38Z2019-02-16T03:01:38ZPutting babies under general anaesthetic won’t affect their development, new research shows<figure><img src="https://images.theconversation.com/files/259207/original/file-20190215-1745-m1gdpa.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">A new study found no detectable impact on brain development.</span> <span class="attribution"><span class="source">From shutterstock.com</span></span></figcaption></figure><p>Making the decision to operate on a baby or toddler can be complex and confronting for parents. It involves weighing the risks versus the expected benefits for the child.</p>
<p>One of the questions impacting the decision has traditionally been whether general anaesthesia is safe for vulnerable, rapidly developing brains.</p>
<p>Parents in this situation can be reassured after a new study published in <a href="https://www.thelancet.com/journals/lancet/article/PIIS0140-6736(18)32485-1/fulltext?rss=yes">The Lancet</a> this week showed a single episode of general anaesthesia in infancy had no detectable impact on subsequent brain development.</p>
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Read more:
<a href="https://theconversation.com/when-your-child-has-to-go-to-hospital-it-is-always-hard-even-when-it-is-for-the-best-42349">When your child has to go to hospital it is always hard - even when it is for the best</a>
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<h2>Why the worry?</h2>
<p>The Food and Drug Administration in the United States <a href="https://www.fda.gov/Drugs/DrugSafety/InformationbyDrugClass/ucm527779.htm">sounded a note of caution</a> as long ago as 2007 after some studies showed some of the gases used in general anaesthesia seemed to have permanent negative effects on the developing brains of rats and monkeys. </p>
<p>Research was planned and funded to settle this issue by examining evidence in the real world. After all, human brains are not the same as rat brains. </p>
<p>Studies that had been <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4101478/">done in humans</a> were observational (backward-looking). This makes it hard to differentiate the effect of the anaesthesia from effects of the condition for which the surgery was being performed, or other factors affecting the child.</p>
<h2>What this study offers</h2>
<p>The strengths of the study are significant. First, it was large, involving 722 participants from children’s hospitals across seven countries, including Australia. </p>
<p>It was also well-designed. In particular, this was a prospective (forward-looking) study with a design that enabled researchers to clearly discern the isolated effect of the anaesthesia. </p>
<p>This was achieved by comparing the same procedure done for the same reason using either spinal anaesthesia, where the patient is numb in the area of surgery but awake, or conventional general anaesthesia, where the patient is unconscious. </p>
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<img alt="" src="https://images.theconversation.com/files/259214/original/file-20190215-1717-171bcsx.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/259214/original/file-20190215-1717-171bcsx.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/259214/original/file-20190215-1717-171bcsx.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/259214/original/file-20190215-1717-171bcsx.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/259214/original/file-20190215-1717-171bcsx.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/259214/original/file-20190215-1717-171bcsx.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/259214/original/file-20190215-1717-171bcsx.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
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<span class="caption">Parents are often worried about the effect an anaesthetic will have on their baby.</span>
<span class="attribution"><span class="source">From shutterstock.com</span></span>
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<p>The procedure chosen for the study was the repair of a <a href="https://www.mayoclinic.org/diseases-conditions/inguinal-hernia/symptoms-causes/syc-20351547">groin hernia</a>, a condition where internal tissues of the abdomen protrude through a weak spot in the abdominal muscle. People who undergo the surgery overwhelmingly have <a href="https://www.ncbi.nlm.nih.gov/pubmed/23932620/">good outcomes and low complication rates</a>. It’s also performed in children who are generally otherwise fairly healthy. </p>
<p>This surgery is usually done within the first couple of months of a child’s life to prevent abnormal development of the lower abdominal wall which would make the hernia difficult and painful to repair later. It also decreases the risk of requiring emergency surgery. </p>
<p>The children recruited into this study were all younger than six months old at the time of surgery. </p>
<p>Another major strength of the study was the length of time the children were followed. Those who were operated on stayed under assessment until they turned five. At this age, the children were given standard tests of brain function which are known to be good at predicting future development. Normal testing at this age would show with a lot of confidence that there was no detriment from the general anaesthesia. And this was found to be the case. </p>
<p>Each of these attributes means the findings are likely to be reliable and able to be generalised from country to country.</p>
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Read more:
<a href="https://theconversation.com/looking-online-for-info-on-your-childs-health-here-are-some-tips-97701">Looking online for info on your child's health? Here are some tips</a>
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<h2>Some things to be aware of</h2>
<p>The only real weakness of the study was that the population assessed was overwhelmingly male (84% of participants) as groin hernia is much more common in baby boys. The authors acknowledge this and highlight the need for future studies to include more girls. </p>
<p>It’s also important to emphasise that in order to enable a clear and definite answer, this study only looked at a single episode of general anaesthesia. It was not designed to assess the risk of repeated or unusually prolonged exposure to general anaesthesia. So it provides a piece of the puzzle, but not the complete picture. </p>
<p>Taken as a whole, this study is reassuring for parents of children undergoing elective surgery at an early age. In a practical sense, it allows other factors such as surgical risk, or the impact of deferring or avoiding the operation, to take a more important place in decision-making. </p>
<p>Parents can put concerns about general anaesthesia harming their baby’s brain to bed for now, at least as far as one-off operations go.</p><img src="https://counter.theconversation.com/content/111727/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Michael Vagg does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>One of the concerns parents have if their baby needs surgery is whether the general anaesthetic will affect the child’s developing brain. New research finds it won’t.Michael Vagg, Clinical associate professor, Deakin University School of Medicine and Pain Specialist, Deakin UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/958602018-06-19T04:44:15Z2018-06-19T04:44:15ZHow old is too old for surgery, and why?<figure><img src="https://images.theconversation.com/files/221699/original/file-20180605-175438-1003hmr.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Many changes in the body occur in response to the injury and trauma inflicted during surgery. </span> <span class="attribution"><span class="source">from www.shutterstock.com</span></span></figcaption></figure><p>Many of us will have been in situations with older loved ones where a doctor says surgery is too risky given the patient’s advanced age. Why is it surgery becomes risky in the elderly, and is it based on chronological age or their health?</p>
<p>During surgery and anaesthesia, there are many changes in the body that occur in response to injury and trauma. This is known as the stress response to surgery.</p>
<p>The surgical stress response results in an increased secretion of hormones that promote the break down of carbohydrates, fats and proteins in the body to provide extra energy during and after surgery. The hormonal changes associated with the surgical stress response also <a href="https://doi.org/10.1093/bja/85.1.109">activate the sympathetic nervous system</a>. </p>
<p>The sympathetic nervous system is responsible for the “fight or flight” response and causes a rise in heart rate and blood pressure. The changes in the heart rate and blood pressure during surgery and anaesthesia create a state where the heart requires more oxygen, while the surgical stress response and anaesthesia often impedes the oxygen supply to the vital organs such as the heart and the brain. This is a result of less blood flow to the body organs during and after the operation.</p>
<p>Anaesthesia confers risks separate from the risks of surgery. These are mostly minor and easy to treat. But serious problems with the heart, lungs and other major organs are more likely during emergency surgery or in the presence of other health conditions. These factors may increase with chronological age, but frailty is the bigger factor for doctors in deciding whether a patient should undergo surgery and anaesthesia.</p>
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Read more:
<a href="https://theconversation.com/why-hip-fractures-in-the-elderly-are-often-a-death-sentence-95784">Why hip fractures in the elderly are often a death sentence</a>
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<h2>Frailty</h2>
<p>Frailty is a state where a person is vulnerable due to decline in body function. This in turn reduces their ability to cope with acute and every day stressors.</p>
<p>In a frail person, there is an accumulation of defects in different organ systems of the body, causing them to function close to the threshold of failure. The organ systems near the threshold of failure are then <a href="https://doi.org/10.1093/qjmed/hcs125">unable to “bounce back”</a> from an external or internal stressor. </p>
<p>An apparently small insult such as a simple fall can result in a significant and disproportionate reduction in reserve and function. The need to have surgery, and the condition that has caused a need for surgery, would often be considered a large insult in a frail person.</p>
<p>Although frailty is more common in older people, it’s not exclusive to older people. Most frail people have chronic health problems, and their frailty increases with the number of chronic health conditions. But most people with chronic health conditions <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4369632/">are not frail</a>. </p>
<p>There are certain health conditions that are more common in people who are frail, such as heart failure, chronic airways disease and chronic kidney disease.</p>
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Read more:
<a href="https://theconversation.com/surgery-isnt-always-the-best-option-and-the-decision-shouldnt-just-lie-with-the-doctor-64228">Surgery isn't always the best option, and the decision shouldn't just lie with the doctor</a>
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<h2>How do we identify frailty and how does it affect health?</h2>
<p>There are <a href="https://doi.org/10.1503/cmaj.050051">many different tools</a> we can use to detect frailty. The Clinical Frailty Scale is one tool based on clinical features present in the patient and the Frailty Index is another tool based on the accumulation of deficits in the patient. </p>
<p>The Clinical Frailty Scale is a single descriptor of a person’s level of frailty using clinical judgement graded from one to nine. Level one is a very fit person; level four is “vulnerable” – where the person is not dependent on others for help with daily activities but does have symptoms that limit activities; and level nine is a terminally ill person.</p>
<p>It has been observed that people with a higher Clinical Frailty Scale were more likely to be older, female, have a degree of cognitive impairment and incontinence. The higher proportion of females will most likely reflect the <a href="https://doi.org/10.1016/S0140-6736(12)62167-9">longer life expectancy of women</a>.</p>
<p>Frail people have a higher risk of recurrent falls and fractures and subsequent disability and reduced function. There have been <a href="https://dx.doi.org/10.1503%2Fcmaj.161403">many studies</a> performed to examine how well frailty predicts outcomes after surgery.</p>
<p>In people who have surgery, frailty has been shown to be associated with a higher risk of surgical complications, a greater chance of requiring discharge to a residential care facility and a lower rate of survival. And the more frail the patient, the higher the risk the patient will require readmission after surgery, and the higher the risk of death.</p>
<p>As our population gets older and more frail people have surgery, this will become an important issue, and health care professionals in all areas will need to be more aware of it.</p><img src="https://counter.theconversation.com/content/95860/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Juliana Kok does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>Doctors may say you’re “too old” for surgery, but what they actually mean is too frail.Juliana Kok, Clinical Lecturer and anaesthetist, The University of MelbourneLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/875382017-11-15T14:47:37Z2017-11-15T14:47:37ZAnthill 19: Pain<figure><img src="https://images.theconversation.com/files/194809/original/file-20171115-19814-iqd2px.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><span class="source">shutterstock.com</span></span></figcaption></figure><p>Pain is something that everyone is familiar with. If you touch a burning stove, a signal travels up your nervous system to your brain which tells you to snatch your hand away. </p>
<p>But understanding pain isn’t so simple. We all experience pain in different ways and the manner in which our brain processes these signals can vary significantly.</p>
<iframe src="https://player.acast.com/5e3bf1111a6e452f6380a7bc/episodes/5e3bf133659d595770f8b922?theme=default&cover=1&latest=1" frameborder="0" width="100%" height="110px" allow="autoplay"></iframe>
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<p>This episode of The Anthill is dedicated to exploring this world of pain. We look into how and why humans experience pain and the efforts underway to better minimise it. Katerina Fotopoulou from UCL’s psychology unit explains how the brain processes pain and why it’s so subjective. Emotions, social relations and context all have a role to play.</p>
<p>In a world of increasingly sophisticated machines, we also explore the question of whether or not robots should feel pain. Conor McGinn, who designs robots involved in the care industry, tells us how far away the technology is from this. And we also address the moral question of whether or not it’s right to inflict feelings of pain onto something you create with Beth Singler, a researcher from the Faraday Institute for Science and Religion at the University of Cambridge, who made a film on this topic called <a href="http://www.cam.ac.uk/research/features/pain-in-the-machine-a-cambridge-shorts-film">Pain in the Machine</a>. It’s the first in a series of four short documentaries considering the implication of AI and robots in relation to human identity. </p>
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<p>From whether or not we should create things that can feel – and even benefit from – pain, we switch to human efforts to remove it entirely.</p>
<p>In fact, the ability to banish pain has been one of the great boons of modern medicine. Unfortunately, the most effective painkillers are based on opium. And like opium, they are addictive and sometimes lethal. Pain experts Marcus Rattray from the University of Bradford and Andrew Moore from the University of Oxford tell us what alternatives are being developed. They also discuss the difficulty of bringing these to market.</p>
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<p><em>Music in the opioid segment is <a href="http://freemusicarchive.org/music/Artofescapism/On_the_Ark__Debut_EP_Album_1636/Attend">Attend by Art Of Escapism</a> and The Anthill theme music is by <a href="https://www.melodyloops.com/search/How+to+Steal+a+Million+Dollars/">Alex Grey for Melody Loops</a>.</em></p>
<p><em>Listen to more episodes of <a href="https://theconversation.com/uk/podcasts/the-anthill">The Anthill</a>, on themes including <a href="https://theconversation.com/anthill-16-humour-me-82845">Humour</a>, <a href="https://theconversation.com/anthill-10-the-future-73404">The Future</a> and <a href="https://theconversation.com/anthill-12-dont-remember-this-76430">Memory</a>.</em> </p>
<p><em>A big thanks to City University London’s Department of Journalism for letting us use their studios to record The Anthill.</em></p><img src="https://counter.theconversation.com/content/87538/count.gif" alt="The Conversation" width="1" height="1" />
Pain is something everyone experiences. This episode of The Anthill podcast explores how and why it works in our brains, what kinds of drugs are being developed to reduce pain, and whether or not robots of the future should be built so that they experience pain.Annabel Bligh, Business & Economy Editor and Podcast Producer, The Conversation UKGemma Ware, Head of AudioStephen Harris, Deputy Editor, The ConversationClint Witchalls, Senior Health EditorLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/837132017-09-11T07:06:20Z2017-09-11T07:06:20ZWe need to close legal loopholes to ensure everyone is safe when going under anaesthesia<figure><img src="https://images.theconversation.com/files/185401/original/file-20170911-9437-hvf4cm.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">We shouldn't have to wait for a disaster to make sure anaesthetics are properly regulated. </span> <span class="attribution"><span class="source">from www.shutterstock.com.au</span></span></figcaption></figure><p>A young woman <a href="http://www.abc.net.au/news/2017-09-02/review-announced-after-botched-breast-surgery-death/8866152">tragically died recently</a> after a cosmetic operation carried out at a beauty clinic. Manslaughter charges have been brought against the practitioner, who allegedly has qualifications obtained overseas but was not registered to practise in Australia. </p>
<p>The Australian and New Zealand College of Anaesthetists, the Royal Australian College of Surgeons and state ministers <a href="http://www.news.com.au/national/breaking-news/doctors-seek-changes-after-salon-death/news-story/93c0d08c878a8e5d3a7835819cd3efee">are examining the regulations</a> around who can deliver sedation and general anaesthesia, and the licensing of using high dose local anaesthesia.</p>
<h2>Who can legally deliver anaesthetics?</h2>
<p>The Australian and New Zealand College of Anaesthetists is the body responsible for the teaching, training and licensing of specialist anaesthetists who are referred to as “fellows”. Specialist anaesthetists have a medical degree, and undergo extensive further training to be qualified to administer anaesthetics.</p>
<p>For many doctors, certification as a specialist anaesthetist is the culmination of more than a decade of examination, full-time training and dedication to the safe practice of anaesthesia and sedation. Specialist anaesthetists practise in many different environments, and not just the operating theatre.</p>
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Read more:
<a href="https://theconversation.com/a-short-history-of-anaesthesia-from-unspeakable-agony-to-unlocking-consciousness-74748">A short history of anaesthesia: from unspeakable agony to unlocking consciousness</a>
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<p>GPs can also receive special training to administer anaesthesia to low risk patients in remote and rural areas, a vital service.</p>
<p>Sedation and local anaesthesia are also frequently used in emergency departments and intensive care units, delivered by doctors who are specialists in areas such as emergency or intensive care medicine. They are trained in anaesthesia with skill sets in airway management and resuscitation. These doctors work in safe environments, and in highly trained teams of nurses and other health professionals.</p>
<p>The <a href="http://www.anzca.edu.au/resources/professional-documents">Australian and New Zealand College of Anaesthetists</a> has several guidelines, specifying a <a href="http://www.medicalboard.gov.au/Codes-Guidelines-Policies/Code-of-conduct.aspx">code of conduct</a>. These include the responsibilities and skills necessary for a medical practitioner to give sedation, criteria for the location in which the anaesthesia is to be administered, patient selection, drug selection, and availability of emergency equipment. These are endorsed by multiple other professional bodies and colleges.</p>
<p>The <a href="https://www.scientificamerican.com/article/propofol-michael-jackson-doctor/">death of Michael Jackson</a> and the <a href="http://www.nbcbayarea.com/news/local/Dental-Anesthesia-Under-Scrutiny-After-Child-Dies-381594491.html">death of a child in California</a> highlight the risks of untrained practitioners administering anaesthetic drugs.</p>
<p>The practitioner in the recent case in Australia was allegedly practising contrary to state regulations, with credentials not recognised in Australia. This <a href="http://www.sbs.com.au/yourlanguage/mandarin/en/article/2017/09/01/beauty-industry-chaotic-and-out-control-woman-dies-following-breast-surgery">may not be uncommon</a>, and is challenging to regulate until disaster occurs.</p>
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<a href="https://images.theconversation.com/files/185404/original/file-20170911-9453-frfj6r.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/185404/original/file-20170911-9453-frfj6r.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/185404/original/file-20170911-9453-frfj6r.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=337&fit=crop&dpr=1 600w, https://images.theconversation.com/files/185404/original/file-20170911-9453-frfj6r.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=337&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/185404/original/file-20170911-9453-frfj6r.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=337&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/185404/original/file-20170911-9453-frfj6r.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=424&fit=crop&dpr=1 754w, https://images.theconversation.com/files/185404/original/file-20170911-9453-frfj6r.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=424&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/185404/original/file-20170911-9453-frfj6r.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=424&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
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<span class="caption">Anyone administering anaesthesia of any kind needs to know how to resuscitate patients in case of emergency.</span>
<span class="attribution"><span class="source">from www.shutterstock.com</span></span>
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</figure>
<h2>How do these disasters occur?</h2>
<p>General anaesthesia and sedation are very safe in Australia when the drugs are administered by doctors with training in pharmacology, airway management and resuscitation. But <a href="http://www.smh.com.au/nsw/unregulated-conscious-sedation-for-cosmetic-surgery-is-putting-lives-at-risk-doctors-warn-20150714-gibp5j.html">there are gaps in the regulation</a>, particularly around “sedation” and local anaesthesia, <a href="http://www.abc.net.au/news/2016-04-20/tci-report-prompts-call-for-national-cosmetic-surgery-laws/7339538">which have been under scrutiny by some groups</a> for some time.</p>
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<em>
<strong>
Read more:
<a href="https://theconversation.com/anaesthesia-the-gift-of-oblivion-and-the-mystery-of-consciousness-book-review-81022">Anaesthesia: the gift of oblivion and the mystery of consciousness – book review</a>
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</em>
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<p>Dentistry and cosmetic surgery are two areas that may be vulnerable to these loopholes. The Australian Health Practitioners Regulation Agency has a <a href="http://www.dentalboard.gov.au/documents/default.aspx?record=WD15%2f18393&dbid=AP&chksum=UuikUcCKpqOJE%2fgp40FdLQ%3d%3d">guide for dentists</a> on administration of intravenous sedation. This is when a drug, usually an anti-anxiety drug, is administered for a dental procedure where the patient stays awake. </p>
<p>The document excludes general anaethesia as dentists are not expected to put patients to sleep during procedures. For intravenous anaesthesia they must have another health-care practitioner present, who may be a nurse. Regulations and licensing of sites varies from state to state, and patient selection and drug dosage are key features of safe practice of this type of sedation.</p>
<p>The regulators of dental sedation and beauty clinics haven’t endorsed the Australian and New Zealand College of Anaesthetists’s guidelines, meaning there are loopholes that can be exploited by dodgy practitioners. </p>
<p>This means a lot of things can happen that are outside the margins of safety, but may not come to light until there is a disaster. Because these loopholes exist in the law, what these practitioners are doing may not be illegal, although unsafe. </p>
<p>There’s a fine balance, which varies greatly between patients, in the margin of safety and effectiveness for the drugs we use to sedate and desensitise patients. Loss of consciousness, and therefore loss of protective reflexes, <a href="https://www.google.com.au/url?sa=t&rct=j&q=&esrc=s&source=web&cd=1&cad=rja&uact=8&ved=0ahUKEwisn6aKhJzWAhWBvpQKHTlqAg4QFggoMAA&url=http%3A%2F%2Fwww.anzca.edu.au%2Fdocuments%2Fps09-2014-guidelines-on-sedation-and-or-analgesia&usg=AFQjCNGexwJNczDHwIfbX5E31Q5GXes40A">can occur rapidly and unexpectedly</a>. This takes many years of training and experience to get right.</p>
<p>Cosmetic surgery is currently under fierce debate in Australia as it falls outside the regulations of the college of surgeons. As the recent case highlights, there are practitioners who are not following the codes of conduct proposed by the regulatory bodies.</p>
<p>This is complicated by a lack of availability (or possibly feasibility) of “appropriate training” outside what is offered by the college of anaesthetists, and the somewhat unpredictable nature of the drugs, especially in inexperienced hands.</p>
<h2>How can you be sure you’re in safe hands when going under?</h2>
<p>Professor David A. Scott, <a href="http://www.anzca.edu.au/communications/media/media-releases-2017-(1)/obese-and-elderly-should-quiz-doctors-about-surgery">the current president of the college of anaesthetists</a> recommends patients choose the location of their surgery wisely - particularly if you’re elderly or have other disease. </p>
<p>Ask the doctor administering the sedation if they have the necessary qualifications and training to do so - and check if they’re on <a href="http://www.ahpra.gov.au/registration/registers-of-practitioners.aspx">Australia’s list of medical practitioners</a> overseen by the <a href="https://www.ahpra.gov.au/">Australian Health Practitioner Regulation Agency</a>. </p>
<p>And we should all make some noise to make sure the government enshrines these regulations in legislation. Until then there will be loopholes for unscrupulous practitioners to use to circumvent the guidelines, compromising safety.</p><img src="https://counter.theconversation.com/content/83713/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Kara Allen is a specialist anaesthetist and a Fellow of the Australian and New Zealand College of Anaesthetists.</span></em></p>After the tragic death of a young woman undergoing a cosmetic procedure, people are rightly asking who should be able to administer anaesthetics.Kara Allen, Clinical Lecturer, Anaesthetist, The University of MelbourneLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/814682017-08-02T04:19:35Z2017-08-02T04:19:35ZWeekly Dose: anaesthetic and recreational drug ketamine could be used to treat depression<figure><img src="https://images.theconversation.com/files/180472/original/file-20170801-5515-ouj9td.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">A small number of people, who probably use other party drugs, use ketamine recreationally. </span> <span class="attribution"><span class="source">from www.shutterstock.com.au</span></span></figcaption></figure><p><a href="http://www.drugs.health.gov.au/internet/drugs/publishing.nsf/content/other4">Ketamine hydrochloride</a> is an anaesthetic that causes people to feel disconnected from their bodies. At low doses, they remain conscious and can talk but do not feel pain. At higher doses, ketamine is used to induce a trance-like state or sedate people with burns or other traumatic injuries. </p>
<p>The drug can be used to perform short operations, particularly on children who are allergic to other drugs. Vets also use ketamine as an anaesthetic.</p>
<p>A small number of people, usually those who also use other party drugs, use ketamine as <a href="https://ndarc.med.unsw.edu.au/sites/default/files/ndarc/resources/TR.111.pdf">a recreational drug</a>. Recreational users are seeking the relaxed and disconnected feeling it causes, as well as hallucinogenic effects that change sight, sound and touch. People may take ketamine accidentally because it is sold as ecstasy or is mixed with ecstasy.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/180489/original/file-20170801-5515-1vekddk.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/180489/original/file-20170801-5515-1vekddk.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/180489/original/file-20170801-5515-1vekddk.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=745&fit=crop&dpr=1 600w, https://images.theconversation.com/files/180489/original/file-20170801-5515-1vekddk.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=745&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/180489/original/file-20170801-5515-1vekddk.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=745&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/180489/original/file-20170801-5515-1vekddk.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=937&fit=crop&dpr=1 754w, https://images.theconversation.com/files/180489/original/file-20170801-5515-1vekddk.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=937&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/180489/original/file-20170801-5515-1vekddk.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=937&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
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<p>In Australia, ketamine is a <a href="https://www.ebs.tga.gov.au/ebs/picmi/picmirepository.nsf/PICMI?OpenForm&t=pi&q=ketamine">Schedule 8</a> or controlled drug sold as Ketamine APOTEX, Ketalar or Ketamine-Claris. <a href="http://www.petplace.com/article/drug-library/library/prescription/ketamine-ketaset-vetalar-vetaket">For animals</a>, it’s sold as Ketaset, Vetalar and Vetaket. </p>
<p>Ketamine is produced as liquid in small bottles for medical use. The liquid is evaporated for recreational use to make a white powder that is snorted, swallowed, or dissolved in water and injected.</p>
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<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/a-short-history-of-anaesthesia-from-unspeakable-agony-to-unlocking-consciousness-74748">A short history of anaesthesia: from unspeakable agony to unlocking consciousness</a>
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</em>
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<h2>A brief history of ketamine</h2>
<p>Ketamine was <a href="http://www.cesar.umd.edu/cesar/drugs/ketamine.asp">discovered in 1962</a> and approved for use in the United States as a battlefield anaesthetic during the Vietnam war.</p>
<p>Calvin L. Stevens, a professor of chemistry at Wayne State University, made ketamine when he was <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5126726/">conducting research on phencyclidine</a> – an anaesthetic also known as angel dust, which worked well but caused hallucinations in people as they woke up. <a href="https://www.ncbi.nlm.nih.gov/pubmed/27965560">Ketamine was named CI-581</a> and was one-tenth as strong as phencyclidine. </p>
<p>After research on animals, ketamine was tested on human prisoners in 1964 and 1965. Guenter Corssen, a professor of anaesthetics, <a href="http://journals.lww.com/anesthesia-analgesia/Citation/1971/05000/Computerized_Evaluation_of_Psychic_Effects_of.26.aspx">conducted experiments on CI-581</a> using prisoners who had volunteered. He found it was a fast-acting anaesthetic that wore off quickly. </p>
<p>Corssen reported that some of the men it was tested on had hallucinations. These included thinking they had died, their arms and legs had been cut off, or they had been to outer space. Some refused to continue in the research. Corssen was the first to call ketamine <a href="https://www.ncbi.nlm.nih.gov/pubmed/20693870">a dissociative anaesthetic</a>, meaning it causes you to feel disconnected from your body. </p>
<p>Ketamine is now on the World Health Organisation’s <a href="http://www.who.int/medicines/publications/essentialmedicines/EML_2015_FINAL_amended_NOV2015.pdf?ua=1">list of essential drugs</a> as an anaesthetic. Ketamine is complicated to make, so is not made illegally. Drug companies manufacture it for medical and veterinary treatment.</p>
<h2>Who uses ketamine?</h2>
<p>Ketamine started being used as a recreational drug in the 1970s because of its dissociative and hallucinogenic effects. But not many people use ketamine. <a href="http://www.aihw.gov.au/alcohol-and-other-drugs/data-sources/ndshs-2016/key-findings/?platform=hootsuite">Use in the past 12 months</a> is reported to be around 0.4% of the Australian population. Only 1.7% ever use ketamine in their lifetime. Lifetime use has doubled since 1999, suggesting greater availability of ketamine for those who want to try it. </p>
<p><a href="http://www.who.int/medicines/areas/quality_safety/4.3KetamineCritReview.pdf">Most people using ketamine</a> will be health or medical professionals who can get it in their workplace, or people in the dance club culture <a href="http://www.drugtrends.org.au/reports/2016-idrs-edrs-key-findings-drug-trends-conference-handout/">who are likely to use other drugs</a>.</p>
<h2>Effects and risks</h2>
<p><a href="http://www.who.int/medicines/areas/quality_safety/4.3KetamineCritReview.pdf">Studies conducted in the 1990s</a> found ketamine caused the same symptoms as schizophrenia – unusual thoughts, hallucinations, trouble explaining things (disorganised speech), emotional withdrawal and difficulty moving. </p>
<p>The effects of ketamine are <a href="http://steinhardt.nyu.edu/appsych/chibps/ketamine">related to the amount taken</a>. A dose of 1-2mg per kilogram of body weight produces an intense experience lasting about one hour. Effects start in less than five minutes if injected, or 30 minutes if swallowed. The effects last about one hour, with all effects wearing off after two to three hours.</p>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/180490/original/file-20170801-12621-1g0a4w8.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/180490/original/file-20170801-12621-1g0a4w8.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/180490/original/file-20170801-12621-1g0a4w8.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=966&fit=crop&dpr=1 600w, https://images.theconversation.com/files/180490/original/file-20170801-12621-1g0a4w8.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=966&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/180490/original/file-20170801-12621-1g0a4w8.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=966&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/180490/original/file-20170801-12621-1g0a4w8.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1214&fit=crop&dpr=1 754w, https://images.theconversation.com/files/180490/original/file-20170801-12621-1g0a4w8.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1214&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/180490/original/file-20170801-12621-1g0a4w8.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1214&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
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<span class="caption">Ketamine has reportedly been used as a date rape drug.</span>
<span class="attribution"><span class="source">from www.shutterstock.com</span></span>
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<p>Larger doses of ketamine cause an anaesthetic effect, or what recreational users refer to as a “K-hole”. A K-hole is generally reached when the user is nearly fully sedated and is described as similar to an out-of-body or near-death experience.</p>
<p><a href="http://www.cesar.umd.edu/cesar/drugs/ketamine.asp">High doses of ketamine</a> can cause breathing problems, muscle twitches, dizziness, slurred speech, nausea and vomiting. People may be injured because of problems with balance, numbness, muscle weakness and poor vision. Probably due to its anaesthetic properties, ketamine has been reported as a “date rape” drug.</p>
<p>There are few reports of overdose or death from ketamine. Dosage is controlled in medical settings according to body weight, and recreationally people tend to use less. The greatest risk is when ketamine is combined with alcohol or other central nervous system depressants, such as opioids or benzodiazepines, which can affect breathing and <a href="http://www.telegraph.co.uk/news/uknews/law-and-order/10633700/Ketamine-death-of-public-schoolgirl-an-act-of-stupidity-which-destroyed-family.html">cause death</a>.</p>
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<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/weekly-dose-valium-the-safer-choice-that-led-to-dependence-and-addiction-59824">Weekly Dose: Valium, the 'safer choice' that led to dependence and addiction</a>
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<p>Ketamine-related deaths can be because of accidents while affected. An example would be <a href="https://www.maps.org/images/pdf/books/K-DreamsKJansenMAPS.pdf">drowning in a bath</a> after taking ketamine and losing consciousness.</p>
<h2>Possible future uses</h2>
<p>Even though it’s a nervous system depressant, ketamine stimulates circulation. This means it doesn’t cause low blood pressure like most anaesthetics, making it useful for <a href="https://www.ncbi.nlm.nih.gov/pubmed/1139377">treating people with head injuries</a>. </p>
<p>Ketamine has been <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4243034/">used as an antidepressant</a> for people with treatment-resistant depression. A low dose of ketamine is given intravenously, with patients reporting effects in two hours that lasted one or two weeks. Although the quality of the evidence supporting positive effects is generally low, initial studies have resulted in interest because ketamine works quickly and appears to <a href="https://www.ncbi.nlm.nih.gov/pubmed/28249076">work on different receptors</a> to traditional antidepressants.</p>
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<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/special-k-ketamines-road-from-tranquilliser-to-possible-antidepressant-8766">Special K: ketamine's road from tranquilliser to possible antidepressant </a>
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</em>
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<p>Ketamine is not approved for the treatment of depression, so this is an off-label use. From June this year a nasal-spray form of ketamine (<a href="http://adisinsight.springer.com/drugs/800037644">esketamine</a>) started clinical trials for treatment of depression.</p>
<p>Australia is conducting the world’s largest study of ketamine as a treatment for depression. A trial of regular ketamine injections <a href="https://www.blackdoginstitute.org.au/news/news-detail/2017/07/24/world-first-ketamine-trial-shows-promise-for-geriatric-depression">helped older people</a> with depression feel less depressed, with about half reporting no depression six months later. But the researchers are cautious about the results because only 16 people participated in the trial.</p>
<p>Another <a href="https://www.blackdoginstitute.org.au/news/news-detail/2016/08/16/world-s-largest-trial-of-ketamine-to-treat-depression-begins">trial is under way</a> with different age groups of people who have tried other treatments that have not reduced their depression.</p>
<p><a href="https://www.ncbi.nlm.nih.gov/pubmed/28249076">Evidence is still limited</a> on ketamine’s effect on depression, the side effects, length of time it is safe to use and if tolerance to the drug will become a problem for people who use it.</p><img src="https://counter.theconversation.com/content/81468/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Julaine Allan has received funding from NHMRC, ARC, RIRDC and NSW Health to undertake research related to drug and alcohol use and treatment.</span></em></p>At higher doses ketamine is used to induce a trance-like state, sedate people with burns or other traumatic injuries, or as an anaesthetic to perform short operations.Julaine Allan, Senior Research Fellow, Charles Sturt UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/749892017-05-18T01:58:35Z2017-05-18T01:58:35ZHealth Check: why can you feel groggy days after an operation?<figure><img src="https://images.theconversation.com/files/164025/original/image-20170405-5739-1u2blpf.png?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Feeling tired or being unable to concentrate is common even days after surgery. But there are simple ways to help speed up your recovery. </span> <span class="attribution"><a class="source" href="https://www.flickr.com/photos/jjay69/5913824188/">Jason Jones/Flickr</a>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span></figcaption></figure><p>You have a small operation under general anaesthesia and go home the same day. Two days later you’re back at work, but you can’t concentrate and have a desperate desire to take a nap. Why does this happen and how can you prevent it?</p>
<p><a href="http://www.anzca.edu.au/patients/what-is-anaesthesia">General anaesthesia</a> is a reversible drug-induced coma, during which you are unconscious, don’t feel pain and don’t remember anything. This is precisely what you want when you’re having an invasive or painful procedure. </p>
<p>However, some people suffer <a href="http://onlinelibrary.wiley.com/doi/10.1111/aas.12381/full">lingering effects</a> in the days after anaesthesia. These include drowsiness, slowed reaction times, and difficulty concentrating, remembering new information and finishing complex tasks.</p>
<p>Thankfully, these unwanted effects usually wear off by the next day, but sometimes they last for a <a href="http://www.sciencedirect.com/science/article/pii/S0022399903006159">few more days or even weeks</a>. Then they can really disrupt your ability to work or get anything done at home.</p>
<h2>It’s easy to blame the anaesthetics</h2>
<p>The effects of general anaesthesia may appear to linger for days after surgery for many reasons. Tiredness after a procedure is commonly attributed to anaesthetics. But modern anaesthetics wear off completely in a <a href="https://www.ncbi.nlm.nih.gov/pubmed/10624999">couple of hours</a>, so the real picture is usually more complicated. </p>
<p>The surgical condition for which you had the procedure may have stopped you leading a full and active life for some time, resulting in lack of fitness and less reserve for recovery.</p>
<p>The surgery itself causes tissue injury. After surgery, your body undergoes repair and recovery, which drives a higher baseline metabolic rate and draws on your nutrient stores. So it isn’t surprising such intense activity at a cellular level results in feeling tired after surgery. </p>
<p>If you ignored your doctor’s advice to take it easy before or after surgery, that could also explain why you’re feeling tired.</p>
<p>Then there’s pain treatment <a href="http://fpm.anzca.edu.au/documents/apmse4_2015_final">before and after the procedure</a>, which can also contribute to grogginess.</p>
<figure class="align-right ">
<img alt="" src="https://images.theconversation.com/files/165413/original/image-20170415-25865-1h0f7fo.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/165413/original/image-20170415-25865-1h0f7fo.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=539&fit=crop&dpr=1 600w, https://images.theconversation.com/files/165413/original/image-20170415-25865-1h0f7fo.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=539&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/165413/original/image-20170415-25865-1h0f7fo.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=539&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/165413/original/image-20170415-25865-1h0f7fo.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=677&fit=crop&dpr=1 754w, https://images.theconversation.com/files/165413/original/image-20170415-25865-1h0f7fo.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=677&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/165413/original/image-20170415-25865-1h0f7fo.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=677&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
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<span class="caption">Strong painkillers you take before or after surgery, like oxycodone, can also make you feel drowsy. But side effects cease once you stop taking them.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/download/confirm/554771338?src=LN8q-gZZ5jerIDiN9S-odQ-1-4&size=medium_jpg">from www.shutterstock.com</a></span>
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<p>For instance, opioids (such as oxycodone) and gabapentinoids (such as pregabalin) are strong pain medicines often prescribed after surgery. They are important in ensuring a comfortable recovery and rapid return to normal life, but may result in grogginess and confusion, especially in higher doses. </p>
<p>Opioids are usually needed <a href="https://www2.health.vic.gov.au/hospitals-and-health-services/quality-safety-service/quality-use-of-medicines/opioid-risk-reduction">for only a few days after surgery</a> and these side effects stop when you stop taking them.</p>
<p>Finally, general anaesthetics <a href="https://academic.oup.com/bja/article/109/5/769/305281/Sleep-disturbances-after-fast-track-hip-and-knee">interfere with your body clock</a>. This <a href="http://www.tandfonline.com/doi/abs/10.1080/07420528.2016.1208664">could be</a> because
anaesthetics <a href="https://www.ncbi.nlm.nih.gov/pubmed/24498074">interfere</a>
with brain hormones, such as melatonin, and messenger chemicals called neurotransmitters.</p>
<p>While <a href="https://nutritionj.biomedcentral.com/articles/10.1186/1475-2891-13-106">melatonin tablets can treat jet lag</a>, which is also a disruption of the body clock, there is no good evidence to use melatonin for anaesthesia-induced body-clock disruption in humans.</p>
<h2>Can you prevent grogginess?</h2>
<p>An operation is a major life event. Make sure you get adequate rest and have enough support at work and home before your surgery.</p>
<p>A bit of anxiety is normal before surgery and can also be exhausting. You can reduce your anxiety by asking for clear explanations of what to expect, and by maintaining a warm, comfortable and calm waiting environment.</p>
<p>If you are very anxious, your <a href="http://www.anzca.edu.au/documents/what-is-an-anaesthetist.pdf">anaesthetist</a> can give you a sedative “pre-med” before you go to theatre. But the use of sedatives is a balancing act, as the calming effect before the procedure is desirable but not the “hangover” drowsiness afterwards, which may last for several hours.</p>
<p>Your anaesthetist is the medically trained specialist who can not only give you a “pre-med” but will look after you during your operation and plan your recovery. He or she will develop an individualised anaesthetic plan based on short-acting anaesthetics and a combination of pain-killings drugs.</p>
<p>Your anaesthetist will also advise you how to best control your pain after surgery and when you return home. This will often involve using simple pain medicines, such as paracetamol and anti-inflammatory drugs, as well as opioids, which you will need to treat strong pain. Using simple pain medicines will help to reduce the doses of opioids that you need, and help you to avoid the nausea, constipation and grogginess that goes with them.</p>
<h2>Get back into good sleep habits</h2>
<p>After a procedure, you can combat the disruption to your body clock by practising good <a href="https://sleepfoundation.org/sleep-topics/sleep-hygiene">“sleep hygiene”</a>. This involves <a href="https://theconversation.com/health-check-five-ways-to-get-a-better-nights-sleep-43700">maximising cues</a> to the body that it is time to sleep in the evening. These could include avoiding stimulants like caffeine and alcohol, going to bed at a similar time each night, being in a <a href="https://theconversation.com/a-dark-night-is-good-for-your-health-39161">dimly lit room</a> and engaging in calming or restful activities before sleep, like reading.</p>
<p>Making sure you are exposed to bright sunshine during the day and <a href="https://theconversation.com/booting-up-or-powering-down-how-e-readers-affect-your-sleep-36145">avoiding back-lit screens</a> on technology devices in the evening can also help.</p>
<p>Lingering grogginess after general anaesthesia is hardly ever sinister. But if it is persistent, getting worse rather than better, or is associated with confusion, weakness or numbness, then you must see your doctor.</p><img src="https://counter.theconversation.com/content/74989/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>The authors do not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and have disclosed no relevant affiliations beyond their academic appointment.</span></em></p>Some people can feel drowsy or can’t concentrate days after an operation. While it’s easy to blame the anaesthetics, the real picture is usually more complicated.Kate Leslie, Honorary professorial fellow, Department of Pharmacology, The University of MelbourneMegan Allen, Honorary Fellow, Anaesthesia, Perioperative and Pain Medicine Unit, Melbourne Medical School, The University of MelbourneLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/747482017-05-01T20:05:08Z2017-05-01T20:05:08ZA short history of anaesthesia: from unspeakable agony to unlocking consciousness<figure><img src="https://images.theconversation.com/files/166194/original/file-20170421-20054-iqgbuw.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">General anaesthesia has come a long way since its first public demonstration in the 19th century, depicted here.</span> <span class="attribution"><a class="source" href="https://commons.wikimedia.org/wiki/File:History_of_surgical_anaesthesia,_Morton,_Diorama_Wellcome_L0003392.jpg">Wellcome Library, London/Wikimedia</a>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span></figcaption></figure><p>We expect to feel no pain during surgery or at least to have no memory of the procedure. But it wasn’t always so.</p>
<p>Until the discovery of general anaesthesia in the <a href="https://www.woodlibrarymuseum.org/history-of-anesthesia/">middle of the 19th century</a>, surgery was performed only as a last and desperate resort. Conscious and without pain relief, it was beset with unimaginable terror, unspeakable agony and considerable risk. </p>
<p>Not surprisingly, few chose to write about their experience in case it reawakened suppressed memories of a necessary torture.</p>
<p>One of the most well-known and <a href="http://burneycentre.mcgill.ca/other_lettersjournalshemlow.html">vivid records</a> of this “terror that surpasses all description” was by <a href="http://burneycentre.mcgill.ca/bio_frances.html">Fanny Burney</a>, a popular English novelist, who on the morning of September 30, 1811 eventually submitted to having a mastectomy:</p>
<blockquote>
<p>When the dreadful steel was plunged into the breast … I needed no injunctions not to restrain my cries. I began a scream that lasted unintermittently during the whole time of the incision … so excruciating was the agony … I then felt the Knife [rack]ling against the breast bone – scraping it. </p>
</blockquote>
<p>But it wasn’t only the patient who suffered. Surgeons too had to endure considerable anxiety and distress.</p>
<p><a href="http://www.magonlinelibrary.com/doi/abs/10.12968/hmed.2014.75.3.174">John Abernethy</a>, a surgeon at London’s St Bartholomew’s Hospital at the turn of the 19th century, <a href="http://catalogue.nla.gov.au/Record/1046414">described</a> walking to the operating room as like “going to a hanging” and was sometimes known to shed tears and vomit after a particularly gruesome operation.</p>
<h2>Discovery of anaesthesia</h2>
<p>It was against this background that general anaesthesia was discovered.</p>
<p>A young US dentist named <a href="http://www.sciencemuseum.org.uk/broughttolife/people/williammorton">William Morton</a>, spurred on by the business opportunities afforded by technical advances in artificial teeth, doggedly searched for a surefire way to relieve pain and boost dental profits. </p>
<p>His efforts were soon rewarded. He discovered when he or small animals inhaled sulfuric ether (now known as <a href="https://pubchem.ncbi.nlm.nih.gov/compound/diethyl_ether">ethyl ether</a> or simply ether) they passed out and became unresponsive.</p>
<p>A few months after this discovery, on October 16, 1846 and with much showmanship, Morton anaesthetised a young male patient in a public demonstration at <a href="http://www.massgeneral.org/anesthesia/about/history.aspx">Massachusetts General Hospital</a>. </p>
<p>The hospital’s chief surgeon then removed a tumour on the left side of the jaw. This occurred without the patient apparently moving or complaining, much to the surgeon’s and audience’s great surprise.</p>
<p>So began the story of general anaesthesia, which for good reason is now widely regarded as one of the <a href="https://www.theatlantic.com/magazine/archive/2013/11/innovations-list/309536/">greatest discoveries</a> of all time.</p>
<h2>Anaesthesia used routinely</h2>
<p>News of ether’s remarkable properties spread rapidly across the Atlantic to Britain, ultimately stimulating the discovery of <a href="https://pubchem.ncbi.nlm.nih.gov/compound/chloroform">chloroform</a>, a volatile general anaesthetic. </p>
<p>According to its discoverer, <a href="https://www.britannica.com/biography/Sir-James-Young-Simpson-1st-Baronet">James Simpson</a>, it had none of ether’s “<a href="https://soap.org/chloroform.php">inconveniences and objections”</a> – a pungent odour, irritation of throat and nasal passages and a perplexing initial phase of physical agitation instead of the more desirable suppression of all behaviour.</p>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/166196/original/file-20170421-20068-bb7yqi.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/166196/original/file-20170421-20068-bb7yqi.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/166196/original/file-20170421-20068-bb7yqi.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=902&fit=crop&dpr=1 600w, https://images.theconversation.com/files/166196/original/file-20170421-20068-bb7yqi.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=902&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/166196/original/file-20170421-20068-bb7yqi.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=902&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/166196/original/file-20170421-20068-bb7yqi.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1133&fit=crop&dpr=1 754w, https://images.theconversation.com/files/166196/original/file-20170421-20068-bb7yqi.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1133&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/166196/original/file-20170421-20068-bb7yqi.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1133&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">This chloroform inhaler was the type John Snow used on Queen Victoria to ease the pain of childbirth. Chloroform vapours were delivered down a tube via the brass and velvet face mask.</span>
<span class="attribution"><a class="source" href="https://commons.wikimedia.org/wiki/File:Snow-type_chloroform_inhaler,_London,_England,_1848-1870_Wellcome_L0058154.jpg">Science Museum, London/Wellcome Images/Wikimedia</a>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span>
</figcaption>
</figure>
<p>Chloroform subsequently became the most commonly used general anaesthetic in British surgical and dental anaesthetic practice, mainly due to the founding father of scientific anaesthesia <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1325279/">John Snow</a>, but remained non-essential to the practice of most doctors.</p>
<p>This changed after Snow gave Queen Victoria chloroform during the birth of her eighth child, Prince Leopold. The publicity that followed made anaesthesia more acceptable and demand increased, whether during childbirth or for other reasons. </p>
<p>By the end of the 19th century, anaesthesia was commonplace, arguably becoming the first example in which medical practice was backed by emerging scientific developments.</p>
<h2>Anaesthesia is safe</h2>
<p>Today, sulfuric ether and chloroform have been replaced by much safer and more effective agents such as <a href="https://www.medicines.org.uk/emc/medicine/49">sevoflurane</a> and <a href="https://www.medicines.org.uk/emc/medicine/41">isoflurane</a>. </p>
<p>Ether was highly flammable so could not be used with <a href="http://emedicine.medscape.com/article/2111163-overview">electrocautery</a> (which involves an electrical current being passed through a probe to stem blood flow or cut tissue) or when monitoring patients electronically. And chloroform was associated with an unacceptably high rate of deaths, mainly due to cardiac arrest (when the heart stops beating).</p>
<p>The practice of general anaesthesia has now evolved to the point that it is among the safest of all major routine medical procedures. For around <a href="https://www.nap.edu/read/9728/chapter/1">300,000</a> fit and healthy people having elective medical procedures, one person dies due to anaesthesia.</p>
<p>Despite the increasing clinical effectiveness with which anaesthesia has been administered for over the past 170 years, and its scientific and technical foundations, we still have only the vaguest idea about how anaesthetics produce a state of <a href="https://theconversation.com/what-makes-us-conscious-50011">unconsciousness</a>.</p>
<h2>Anaesthesia remains a mystery</h2>
<p>General anaesthesia needs patients to be immobile, pain free and unconscious. Of these, <a href="https://theconversation.com/is-anyone-there-about-consciousness-and-its-disorders-54035">unconsciousness is the most difficult</a> to define and measure.</p>
<p>For example, not responding to, or then not remembering, some event (such as the voice of the anaesthetist or the moment of surgical incision), while clinically useful, is <a href="https://theconversation.com/scientists-find-way-to-predict-who-is-likely-to-wake-up-during-surgery-53217">not enough to decisively determine</a> whether someone is or was unconscious.</p>
<p>We need some other way to define consciousness and to understand its disruption by the biological actions of general anaesthetics. </p>
<p>Early in the 20th century, we thought anaesthetics worked by dissolving into the fatty parts of the outside of brain cells (the cell membrane) and interfering with the way they worked.</p>
<p>But <a href="http://www.nature.com/nrn/journal/v5/n9/full/nrn1496.html">we now know anaesthetics directly affect the behaviour of a wide variety of proteins</a> necessary to support the activity of neurones (nerve cells) and their coordinated behaviour.</p>
<p>For this reason the only way to develop an integrated understanding of the effects of these multiple, and individually insufficient, neuronal protein targets is by developing testable, <a href="http://www.nature.com/neuro/journal/v20/n3/full/nn.4497.html">mathematically formulated</a> theories.</p>
<p>These theories need to not only describe how consciousness emerges from brain activity but to also explain how this brain activity is affected by the multiple targets of anaesthetic action.</p>
<p>Despite the tremendous advances in the science of anaesthesia, after almost 200 years we are still waiting for such a theory.</p>
<p>Until then we are still looking for the missing link between the physical substance of our brain and the subjective content of our minds.</p><img src="https://counter.theconversation.com/content/74748/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>David Liley receives funding from the James S. McDonnell Foundation. He owns shares in Cortical Dynamics Ltd. </span></em></p>Terrifying accounts of surgery 200 years ago remind us how far general anaesthesia has come. Yet we still know little about how anaesthetics alter consciousness.David Liley, Professor, Centre for Human Psychopharmacology, Swinburne University of TechnologyLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/648702016-10-31T23:46:42Z2016-10-31T23:46:42ZExplainer: what is an epidural for labour?<figure><img src="https://images.theconversation.com/files/142443/original/image-20161020-5004-8ez06v.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">An epidural takes up to 45 minutes to work, so if the baby's coming it could be too late. </span> <span class="attribution"><a class="source" href="http://www.shutterstock.com/downloading_tips.mhtml?code=&id=162604985&size=medium&image_format=jpg&method=download&super_url=http%3A%2F%2Fdownload.shutterstock.com%2Fgatekeeper%2FW3siZSI6MTQ3Njk1ODc4OCwiYyI6Il9waG90b19zZXNzaW9uX2lkIiwiZGMiOiJpZGxfMTYyNjA0OTg1IiwiayI6InBob3RvLzE2MjYwNDk4NS9tZWRpdW0uanBnIiwibSI6IjEiLCJkIjoic2h1dHRlcnN0b2NrLW1lZGlhIn0sInZKUHJ6ZER4L1dyc2tjYngybmRja2JjeVA3USJd%2Fshutterstock_162604985.jpg&racksite_id=ny&chosen_subscription=134&license=multi_share&src=Bs5k9y1aTXv8sZMsGzOLTQ-1-19">from www.shutterstock.com.au</a></span></figcaption></figure><p><a href="http://onlinelibrary.wiley.com/doi/10.1002/14651858.CD009234.pub2/abstract">Epidurals were developed</a> for pregnant women to address the severe pain of labour. In Australia about <a href="http://www.aihw.gov.au/publication-detail/?id=60129553770">one in three</a> pregnant women in labour has an epidural for this reason.</p>
<p>A specialised medical doctor who has training and experience in this technique performs it in a hospital with an epidural service. This doctor is <a href="http://www.anzca.edu.au/documents/ps03-2014-guidelines-for-the-management-of-major-r.pdf">usually an anaesthetic consultant</a> (anaesthetist) or a trainee under their supervision, or a GP anaesthetist.</p>
<p>An epidural is sometimes called a “major regional block” because a large region of the body has pain blocked in it, or a “neuraxial block” because it blocks the pain nerves around the middle axis of the body.</p>
<h2>Why is it sometimes ‘too late’?</h2>
<p>A woman must request an epidural and give her consent before the procedure. The doctor then inserts an intravenous line (an “IV”). The procedure is performed between contractions, with the woman sitting up or lying on her side. It is safe to have an epidural early in labour or even before labour is induced as long as the woman <a href="http://www.cochrane.org/CD007238/PREG_early-versus-late-initiation-of-epidural-analgesia-for-labour">has no medical reason</a> to avoid one. </p>
<p>Medical reasons include conditions that increase the risk of bleeding and infection around the spinal nerves, which can lead to spinal nerve damage.</p>
<p>Another reason is if a woman is fully dilated or just about to give birth as there may not be time for an epidural. This is because the procedure itself takes time to perform, may be challenging to perform at this stage of labour due to pushing and the need for the woman to keep very still, and it then takes time for the medications to work.</p>
<p>In general, the aim is for women to have adequate pain relief <a href="https://www.ncbi.nlm.nih.gov/pubmed/15477051">45 minutes after the epidural procedure</a> has started. If birth is expected within this time, the risks of an epidural, outlined below, are generally thought to outweigh the benefits of possible pain relief.</p>
<h2>How is it administered?</h2>
<p>An epidural involves placing a very small soft plastic tube into the epidural space in the lower part of the back. The epidural space is near the spine in the central part of the back, where the pain nerves of childbirth are located. </p>
<p>The doctor usually delivers two different types of medications down the epidural tube into the epidural space. These are local anaesthetics (drugs like lignocaine, commonly used to numb tooth pain for dental work) and morphine-like medications (opioids). </p>
<p>The two different drugs work together to improve pain relief. This means less of each drug can be used so there is less likelihood of side effects. These medications then surround the nerves and block signals from the nerves to relieve pain.</p>
<p>The medications block mainly the small pain nerves, and not the large muscle nerves. This means a woman can still move her legs and push effectively, while getting pain relief. This is often known as a “light epidural”.</p>
<p>One recent technique is known as patient controlled epidural analgesia. This is when a woman can press a button to control the delivery of medication into the epidural space, and so the amount of pain relief she receives.</p>
<p>A woman usually has to stay in bed during an epidural for labour or birth. This is because the epidural can also block some other small nerves (those that control balance), so increasing the risk of a fall.</p>
<h2>What are the advantages?</h2>
<p>While the major advantage of an epidural is to provide complete or near complete pain relief for labour, other advantages include reducing blood pressure spikes during the pain of contractions in women with high blood pressure (preeclampsia) and <a href="https://www.thewomens.org.au/patients-visitors/cbe/cbepark/twins-triplets-and-more/">allowing twins to be safely delivered vaginally</a>.</p>
<p>Another advantage is if the woman needs a caesarean section then the epidural can often be simply “topped up”. This means the doctor delivers a different medication or an increased amount of the same medication via the epidural tube.</p>
<p>This leads to a <a href="http://www.cochrane.org/CD004350/PREG_regional-versus-general-anaesthesia-for-caesarean-section">much stronger epidural block</a> causing the woman’s legs to become very heavy and pain relief to extend higher up her body to her breasts. This is needed so the woman does not feel pain during surgery yet she is awake to experience the birth. In the past this type of epidural was commonly used during labour and was known as a “heavy epidural”. </p>
<h2>What are the risks?</h2>
<p>It is important to monitor the woman and the unborn baby when a woman has an epidural because there can be changes in her blood pressure or the unborn baby’s heart rate. </p>
<p>There is no increased risk of caesarean section with an epidural, however women who have an epidural have on average a 14 minute longer second stage of labour - when the woman is fully dilated until she gives birth. There’s also an increased risk of needing instruments such as forceps during a vaginal birth (<a href="http://www.cochrane.org/CD000331/PREG_epidurals-for-pain-relief-in-labour">one woman in eight without</a> an epidural compared with one in six women with an epidural). </p>
<p>Sometimes an epidural can fail. <a href="https://www.ncbi.nlm.nih.gov/pubmed/15321183">There may have been a failure</a> to locate the epidural position (sometimes due to the anatomy of the woman), pain may continue 45 minutes after the initiation of the epidural, replacement of an epidural is needed if it is not working, there is patchy or one-side anaesthesia, or there is an accidental puncture in the layer of tissue around the spinal canal known as the dura.</p>
<p>The <a href="https://www.ncbi.nlm.nih.gov/pubmed/15477051">criteria and standards</a> for <a href="https://www.ncbi.nlm.nih.gov/pubmed/15321183">best practice</a> when a hospital department offers an epidural pain relief service for pregnant women include at least 88% of women having adequate pain relief 45 minutes from the start of the epidural procedure, fewer than 15% of women having their epidural replaced at any point during labour, fewer than 1% of women having an accidental dural puncture, at least 85% of women having an excellent epidural experience overall, and at least 98% of women being satisfied with their pain relief in labour.</p>
<p>In Australia we are fortunate to have skilled, specialised medical doctors who work as part of a team to provide pregnant women with choice, and safe and effective anaesthesia so their experience of childbirth can be pain free and enjoyable.</p><img src="https://counter.theconversation.com/content/64870/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Alicia Dennis receives funding from NHMRC ECF Health Practitioner Fellowship, is a Fellow of the Australian and New Zealand College of Anaesthetists, is Chair of the Public Practice Advisory Committee of the Australian Society of Anaesthetists, and is a staff specialist anaesthetist and Director of Anaesthesia Research at the Royal Women's Hospital, Parkville, Australia </span></em></p>Epidurals were developed for pregnant women to address the severe pain of labour. In Australia approximately one in three pregnant women in labour has an epidural for pain relief.Alicia Dennis, Associate Professor of Obstetric Anaesthesia, MBBS, PhD, PGDipEcho, FANZCA, The University of MelbourneLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/532172016-01-22T03:33:12Z2016-01-22T03:33:12ZScientists find way to predict who is likely to wake up during surgery<figure><img src="https://images.theconversation.com/files/108531/original/image-20160119-29750-qak84k.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Doctors currently have no perfectly reliable way of ensuring patients are adequately unconscious before an operation begins.</span> <span class="attribution"><span class="source">from shutterstock.com</span></span></figcaption></figure><p>Measuring certain kinds of brain activity may help doctors track and predict how patients will react to anaesthesia before going under for surgery, <a href="http://journals.plos.org/ploscompbiol/article?id=info:doi/10.1371/journal.pcbi.1004669">our research has found</a>.</p>
<p>Doctors currently have no perfectly reliable way of ensuring patients are adequately unconscious before an operation begins. Although rare, the uncertainty sometimes results in traumatic experiences of patients “waking up” during surgery.</p>
<p>Using a technique that measures electrical impulses in the brain of those in various states of sedation, we discovered network “signatures” that can indicate when loss of consciousness will occur.</p>
<p>Doctors can use similar techniques to accurately identify the concentration of drug needed for a patient to lose consciousness and maintain that loss throughout an operation.</p>
<h2>Everyone is different</h2>
<p>Every day in Australia, <a href="http://www.anzca.edu.au/resources/college-publications/pdfs/ANZCA%20Mortality%20Report%20FINAL.pdf">more than 6,000 people</a> are anaesthetised for surgery. Doctors need to figure out exactly how much sedative to give them, and keep them unconscious throughout the operation.</p>
<p>Anaesthetists estimate the concentration of sedative required using calculations mainly <a href="http://www.frca.co.uk/article.aspx?articleid=101001">based on a patient’s</a> weight. As the patient “goes under”, their level of awareness is monitored by observing indirect – and somewhat crude – measures, such as blood pressure, heart rate or physical movement. </p>
<p>This method works well in most cases, but people’s susceptibility to anaesthesia varies. One to two in every 1,000 people <a href="http://www.ncbi.nlm.nih.gov/pubmed/15172773">report having some awareness</a> or recall during surgery. This equates to 2,000 to 4,000 such cases each year in Australia.</p>
<p>Recollections include hearing people speaking during surgery, sensations of not being able to breathe, and experiencing pain. </p>
<p>Naturally, experiences such as these are emotionally traumatic. What’s more, many suffer mental distress long after the surgery, resulting in negative memories of their hospital experience. Some have even <a href="http://www.jointcommission.org/assets/1/18/SEA_32.pdf">reported a reduction</a> in their quality of life.</p>
<h2>Losing consciousness</h2>
<p>Figuring out the best way to sedate someone essentially comes down to understanding how the brain gains and loses consciousness; that is, the inner world of awareness, feelings and sensations. Although a challenging theme in neuroscience, rapid advances have been made in this area.</p>
<p>Some theories <a href="http://bmcneurosci.biomedcentral.com/articles/10.1186/1471-2202-5-42">suggest that key networks</a> of <a href="https://www.researchgate.net/publication/44642456_Two_Distinct_Neuronal_Networks_Mediate_the_Awareness_of_Environment_and_of_Self">brain areas communicate</a> with each other to integrate information processing and generate consciousness. This communication network gives off signals that indicate how conscious an individual is.</p>
<p>The networks come about <a href="http://www.ncbi.nlm.nih.gov/pubmed/23487781">from brain neurons</a> firing simultaneously at a certain frequency. We can observe them by using a non-invasive technique called electroencephalogram (EEG), where sensors placed on the scalp record the neurons’ electrical impulses. These recordings provide us with a brain “signature” indicative of awareness levels.</p>
<p>Brain monitoring such as this is not commonly used in the operating theatre today. One reason is that current devices are unable to deal with the considerable variability in how people respond to sedatives. But our study shows that devices calibrated for accurate monitoring based on the latest neuroscientific advances could help reduce the incidence of awareness during surgery. </p>
<h2>Our study</h2>
<p>We have <a href="http://www.cam.ac.uk/research/news/scientists-find-hidden-brain-signatures-of-consciousness-in-vegetative-state-patients">previously shown</a> that network signals of consciousness can also be seen in some people in a vegetative state. </p>
<p>This gave us an indication of the types of signals that could be seen in those who experience some awareness during surgery, but are unable to communicate. But we also needed to show that a similar brain-based measure worked well in cases where we could manipulate the level of consciousness.</p>
<p>Our <a href="http://journals.plos.org/ploscompbiol/article?id=info:doi/10.1371/journal.pcbi.1004669">latest study</a>, published in the journal PLOS Computational Biology, helped us better understand the transition to unconsciousness during sedation, and how this transition varies from person to person. </p>
<p>We gave a steadily increasing dose of a commonly used anaesthetic called propofol to 20 people. At the same time, we measured the brain networks known to be associated with consciousness using EEG. The drug was administered at different dosages, causing varying degrees of mild to moderate sedation across our participant group, rather than complete unconsciousness in all of them.</p>
<p>We also measured the behavioural responsiveness of the participants with a simple task. They were asked to press one button if they heard a “ping” and a different button if they heard a “pong”. </p>
<p>Alongside this, we recorded the concentration of the drug in their blood at different times. Altogether, we got the information needed to connect the activity of their brain networks to their individual drug responses.</p>
<h2>The right measure</h2>
<p>We found that the strength of a participant’s brain network was clearly linked to their behavioural responsiveness. In other words, as the brain network indicating consciousness weakened, behavioural evidence of awareness also diminished.</p>
<p>Interestingly, while some participants showed behavioural evidence of consciousness at moderate levels of the anaesthetic, others remained responsive. </p>
<p>We found that it was actually the strength of their brain networks before sedation that predicted why some eventually lost consciousness while others did not. In other words, people with weaker baseline networks of consciousness were able to lose it more quickly than those with stronger baselines.</p>
<p>Our current findings indicate the change in consciousness due to the sedative was clearly correlated with specific patterns of brain network activity. This gives us confidence in making the “reverse inference” that tracking this network activity can be used to infer the true level of consciousness in the absence of behaviour. </p>
<p>Further engineering and testing could help advance and adapt current brain monitoring technology for use in the operating theatre. It is clear that networks measured by an appropriate EEG can capture and explain why people respond differently to anaesthesia. </p>
<p>This monitoring can help doctors optimise the amount of drug needed for someone to become unconscious without increasing risk of complications or awareness during surgery.</p><img src="https://counter.theconversation.com/content/53217/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Srivas Chennu receives funding from the James S. McDonnell Foundation, National Institute for Health Research (UK), and the Evelyn Trust. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. </span></em></p>Measuring certain kinds of brain activity may help doctors track and predict how patients will react to anaesthesia before going under for surgery, our research has found.Srivas Chennu, Senior Research Associate, University of CambridgeLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/220622014-01-16T00:16:57Z2014-01-16T00:16:57ZOhio execution: lethal injections are based on guesswork<figure><img src="https://images.theconversation.com/files/39146/original/hgjr3jnr-1389804173.jpg?ixlib=rb-1.1.0&rect=0%2C3%2C1280%2C860&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Designed for other uses.</span> <span class="attribution"><span class="source">Phil and Pam</span></span></figcaption></figure><p>Ever since the time of the guillotine, doctors have been at the centre of the death penalty. Joseph Guillotin, the physician who suggested the device be used in 18th-century France, was actually against the death penalty – he hoped that a more humane method of decapitation would be a prelude to ending capital punishment. </p>
<p>It was nearly 200 years later, in 1977, that the end came for the guillotine. That same year, anaesthetist Stanley Deutsch proposed the so-called triple cocktail for lethal injection, consisting of a fast-acting anaesthetic (sodium thiopental), a muscle-paralysing agent (pancuronium) and a cardiotoxin (potassium chloride) to stop the heart for an execution in Oklahoma. There was a perception that this might be somehow more humane, despite reports of botched executions – deaths that took longer than they should, signs of skin burns and convulsions – and more than 1100 prisoners have been executed in this way. </p>
<p>But pressure by drug manufacturers and European export controls mean the supply of these drugs (and subsequent substitutions such as pentobarbital, a barbituate used for severe forms of epilepsy) is now limited, leading to executing states using different concoctions and combinations. The reported last words of Michael Lee Wilson in Oklahoma earlier this month, that he felt his “whole body burning” around 20 seconds into his execution, prompted <a href="http://www.theguardian.com/world/2014/jan/13/ohio-man-execution-lethal-injection-method">some to suggest</a> this may have played a part. </p>
<h2>Untested drugs?</h2>
<figure class="align-left ">
<img alt="" src="https://images.theconversation.com/files/39144/original/6kqrdyqb-1389803608.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/39144/original/6kqrdyqb-1389803608.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=600&fit=crop&dpr=1 600w, https://images.theconversation.com/files/39144/original/6kqrdyqb-1389803608.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=600&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/39144/original/6kqrdyqb-1389803608.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=600&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/39144/original/6kqrdyqb-1389803608.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=754&fit=crop&dpr=1 754w, https://images.theconversation.com/files/39144/original/6kqrdyqb-1389803608.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=754&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/39144/original/6kqrdyqb-1389803608.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=754&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Dennis McGuire.</span>
<span class="attribution"><span class="source">Ohio Dept of Rehabilitation and Correction</span></span>
</figcaption>
</figure>
<p>Much has been made about untested drugs being used in Ohio’s <a href="http://www.usatoday.com/story/news/nation/2014/01/13/judge-wont-stop-ohio-execution-by-untried-drugs/4454099/">execution</a> of Dennis McGuire, because the state opted to use a sedative called midazolam and a painkiller, hydromorphone, due to a shortage of pentobarbital. </p>
<p>In one sense being untested is true of all drugs used in executions, as no pharmaceutical company has ever developed a drug to be used to kill someone – this would be in complete breach of medical ethics. As a consequence, the executioners had to make a guess (and not necessarily an educated one) about what the lethal toxic dose is of the drug concerned.</p>
<h2>Exporting death</h2>
<p>The biggest change to how lethal injections are used came in 2011, when the European Union (which is fundamentally opposed to the death penalty) <a href="http://content.time.com/time/world/article/0,8599,2102266,00.html">introduced export controls</a> to prevent drugs being used for executions. </p>
<figure class="align-right ">
<img alt="" src="https://images.theconversation.com/files/39142/original/42j6q4hk-1389799139.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/39142/original/42j6q4hk-1389799139.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=720&fit=crop&dpr=1 600w, https://images.theconversation.com/files/39142/original/42j6q4hk-1389799139.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=720&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/39142/original/42j6q4hk-1389799139.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=720&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/39142/original/42j6q4hk-1389799139.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=905&fit=crop&dpr=1 754w, https://images.theconversation.com/files/39142/original/42j6q4hk-1389799139.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=905&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/39142/original/42j6q4hk-1389799139.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=905&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Off labelling.</span>
<span class="attribution"><span class="source">James Heilman </span></span>
</figcaption>
</figure>
<p>The ban on exports of sodium thiopental for executions led the US to switch to pentobarbital. Then following pressure from the medical profession and others, Lundbeck, the Danish manufacturer of pentobarbital (sold as Nembutal), introduced a controlled <a href="http://nation.time.com/2013/08/07/the-hidden-hand-squeezing-texas-supply-of-execution-drugs/">distribution mechanism</a> to tighten up its supply chain, preventing use by US prisons.</p>
<p>Despite <a href="http://www.texasmonthly.com/story/texas-began-stockpiling-execution-drugs-shortage">attempts at stockpiling</a> by executioners, the shelf life of their pentobarbital was limited to 2013.</p>
<p>The next switch was (to a very limited degree) propofol, the world’s most widely used anaesthetic and the drug infamously involved <a href="http://www.telegraph.co.uk/culture/music/michael-jackson/10272782/Michael-Jackson-sought-propofol-long-before-death-says-doctor.html">in the botched</a> (and fatal) treatment of Michael Jackson.</p>
<p>When German firm Fresenius Kabi, which supplies the majority of the drug to the US, curbed shipments after it learned that Missouri’s Department of Corrections had bought <a href="http://www.economist.com/news/united-states/21588916-technical-hitch-stays-executioners-needle-cruel-and-unusable">an unsanctioned batch</a>, Missouri governor Jay Nixon was so worried about the risk to supplies of propofol for patient care last October that he blocked the execution of Allen Nicklasson. He said his interest was “in making sure justice is served and public health is protected.”</p>
<p>All these drugs are important for use in critical care units or operating theatres in hospitals. They weren’t developed to be used in an execution chamber with <a href="http://bit.ly/19u2rTb">poorly trained</a> non-medical staff.</p>
<p>The pressure from manufacturers and countries that don’t want their drugs involved in executions has had a massive impact. The numbers of executions in the US last year fell to <a href="http://www.npr.org/2013/12/19/255397766/executions-in-u-s-drop-close-to-20-year-low-in-2013">the lowest level</a> since 1994 with 39 prisoners executed in 2013 in the US.</p>
<h2>Homemade solutions</h2>
<p>Executioners in the US have been forced to look at alternatives, for example the use of <a href="http://health.howstuffworks.com/medicine/healthcare/what-is-a-compounding-pharmacist.htm">compounding pharmacies</a> who are allowed to make small batches of a prescribed medication. But such <a href="http://online.wsj.com/news/articles/SB10001424052702303754404579312680341438784">unregulated</a> pharmacies are also controversial in the US; as recently as 2012, botched manufacturing processes led to sizeable fungal meningitis outbreaks. </p>
<p>Other death penalty countries also use lethal injections, <a href="http://www.telegraph.co.uk/news/worldnews/1574560/Lethal-injection-replaces-firing-squad-in-China.html">increasingly</a> and most notably China, where the process is even more secretive. </p>
<p>And the effect of the EU restrictions has been global, not just limited to the US – even Vietnam has struggled to execute prisoners on death row and is considering <a href="http://www.theguardian.com/world/2013/nov/08/vietnam-firing-squad-executions">resuming executions</a> by firing squad.</p>
<p>It’s clear the problems with supply plus the desperation of executioners to find replacement drugs have highlighted that the lethal injection method is anything but a humane process.</p><img src="https://counter.theconversation.com/content/22062/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>David Nicholl does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>Ever since the time of the guillotine, doctors have been at the centre of the death penalty. Joseph Guillotin, the physician who suggested the device be used in 18th-century France, was actually against…David Nicholl, Consultant Neurologist & Honorary Senior Lecturer, University of BirminghamLicensed as Creative Commons – attribution, no derivatives.