Do we anaesthetise too many children? by Quentin Smith
[Published in Anaesthesia News no. 321 April 2014]
Paracelsus, a 16thC Swiss physician and alchemist, famously wrote: “All things are poison, and nothing is without poison; only the dose permits something not to be poisonous.”
His insight was remarkable. Consider even water, essential for sustaining life, but too much - whether oral or intravenous - is poison; oxygen is also essential for sustaining life, but too much is poison, causing significant cellular damage.
It has been a long time since we have had to endure surgery without access to anaesthesia and popular lists of those inventions that have most changed human existence for the better always include anaesthesia near the top. It has also been a long time since we have faced significant loss of confidence in the safety of anaesthesia, with the days of high anaesthetic morbidity and mortality from ether and chloroform and curare long forgotten to the modern generation.
The miracle of fully reversible anaesthesia is truly profound: a state of induced deep coma, suppression of nociceptive reflexes compatible with a diagnosis of brain death followed by rapid and complete return to normal upon discontinuation. Furthermore, competent anaesthesia has never been as safe as it is today with the likelihood of mortality in healthy subjects so low as to be beyond the comprehension of most people.
When one considers the widespread actions of general anaesthetic agents, both receptor-mediated and molecular, identified and undefined, it is perhaps not that surprising that scientists are now discovering that anaesthesia can cause irreversible changes. Gene and protein expression we now know are altered beyond safe emergence from anaesthesia. [1] Neuronal apoptosis in developing brains undergoing synaptogenesis is another very real and concerning finding. Children who have undergone anaesthesia during this vulnerable window have been found lagging behind their matched cohorts in neuro-developmental scores.[1]
It appears likely that there is a threshold for damage, both dose, time and stage of maturing brain: current evidence suggests under 3 years of age (by which time synaptogenesis is complete) and more than 3 hours of anaesthesia with multiple anaesthetics worse than a single exposure. [2] But findings, though deeply concerning, are still at times conflicting and inconclusive.
Suddenly, though, for the first time in our professional lives, we are faced with the distinct possibility that the drugs we administer to our youngest patients to enable painless surgical interventions may leave a long-lasting negative impact on their lives.
Cause for concern? YES. Cause for continued research? DEFINITELY. Cause to adjust sound clinical practice? NO. Stay tuned… [3]
But what exactly is sound clinical practice in our vulnerable young patients? There will always be clear indications for surgical intervention and in these cases the risks of anaesthesia will have to be born as the only alternative to the days of Robert Liston’s 28 second amputations under sturdy muscular restraint. But there will also be those cases where necessity and indication for intervention requiring general anaesthesia will be less clear cut. So what can we as anaesthetists do to minimise the potential of permanent neuro-developmental harm to our youngest patients whilst the concentrated efforts of international studies, GAS (a multi-site randomised controlled trial comparing regional and general anaesthesia for effects on neuro-developmental outcome and apnoea in infants) and PANDA (paediatric anaesthesia neuro-developmental assessment study) hope to shed more light on these worrying findings over the next few years?
We cannot choose safer anaesthetic agents because all volatile and intravenous anaesthetic agents are implicated. It is also unlikely that any new ‘wonder drug’ anaesthetic agent will be produced as there are no new volatile or intravenous anaesthetics even in the earliest stages of R&D - there is simply no commercial drive to develop new anaesthetic agents. We could employ regional anaesthesia a little more, but its role in very young children will always be limited.
About the only immediate action we can take to limit the damage is to anaesthetise only those at risk children who really need surgery. The immediate question is: have we become complacent in not just medicine but society in general, accepting as a ‘means to an easier end’ the welcome safety of modern general anaesthesia? Every anaesthetist will be able to identify in their own practice the numerous cases undergoing ‘safe’ anaesthesia for incredibly minor and even sometimes ‘unnecessary’ procedures. Where do we draw the line, though, if the safety aspect of anaesthesia is under question? Do we, in this era of informed consent and patient empowerment, face a return to more paternalistic decision making in denying general anaesthesia to at risk patients for procedures we professionals regard as ‘unnecessary’?
Though there are still more questions than answers, it behoves all of us to communicate these legitimate concerns to our surgical colleagues and work with them in minimising the number of young children whom we expose ‘unnecessarily’ and repeatedly to general anaesthesia.
The surgeons will also be able to focus their thresholds for intervention more tightly and identify alternative interventions: eg steri strips instead of suturing tiny lacerations; hearing aids instead of grommets until older; investment in education and prevention rather than annual extractions of rotten teeth; leaving tiny moles and skin tags until older, and many more.
Paracelsus may well have been right all along.
[1] Are anaesthetics toxic to the brain? Hudson AE, Hemmings Jr HC. Br J Anaes 2011 doi:10.1093/bja/aer122
[2] Hemmings Jr HC. Personal communication: RCoA Recent Advances in Anaesthesia, Critical Care and Pain; Nottingham 3-5 December 2013
[3] Neurotoxicity of General Anesthetics. Cause for Concern? Perouansky M, Hemmings Jr HC. Anesthesiology 2009; 111(6): 1365-1371. doi:10/ALN.0b013e3181bf1d61
[declaration of interest: Quentin Smith is the author of Huber’s Tattoo, centred around the science of eugenics and engineering human intelligence, pub. February 2014]
[Published in Anaesthesia News no. 321 April 2014]
Paracelsus, a 16thC Swiss physician and alchemist, famously wrote: “All things are poison, and nothing is without poison; only the dose permits something not to be poisonous.”
His insight was remarkable. Consider even water, essential for sustaining life, but too much - whether oral or intravenous - is poison; oxygen is also essential for sustaining life, but too much is poison, causing significant cellular damage.
It has been a long time since we have had to endure surgery without access to anaesthesia and popular lists of those inventions that have most changed human existence for the better always include anaesthesia near the top. It has also been a long time since we have faced significant loss of confidence in the safety of anaesthesia, with the days of high anaesthetic morbidity and mortality from ether and chloroform and curare long forgotten to the modern generation.
The miracle of fully reversible anaesthesia is truly profound: a state of induced deep coma, suppression of nociceptive reflexes compatible with a diagnosis of brain death followed by rapid and complete return to normal upon discontinuation. Furthermore, competent anaesthesia has never been as safe as it is today with the likelihood of mortality in healthy subjects so low as to be beyond the comprehension of most people.
When one considers the widespread actions of general anaesthetic agents, both receptor-mediated and molecular, identified and undefined, it is perhaps not that surprising that scientists are now discovering that anaesthesia can cause irreversible changes. Gene and protein expression we now know are altered beyond safe emergence from anaesthesia. [1] Neuronal apoptosis in developing brains undergoing synaptogenesis is another very real and concerning finding. Children who have undergone anaesthesia during this vulnerable window have been found lagging behind their matched cohorts in neuro-developmental scores.[1]
It appears likely that there is a threshold for damage, both dose, time and stage of maturing brain: current evidence suggests under 3 years of age (by which time synaptogenesis is complete) and more than 3 hours of anaesthesia with multiple anaesthetics worse than a single exposure. [2] But findings, though deeply concerning, are still at times conflicting and inconclusive.
Suddenly, though, for the first time in our professional lives, we are faced with the distinct possibility that the drugs we administer to our youngest patients to enable painless surgical interventions may leave a long-lasting negative impact on their lives.
Cause for concern? YES. Cause for continued research? DEFINITELY. Cause to adjust sound clinical practice? NO. Stay tuned… [3]
But what exactly is sound clinical practice in our vulnerable young patients? There will always be clear indications for surgical intervention and in these cases the risks of anaesthesia will have to be born as the only alternative to the days of Robert Liston’s 28 second amputations under sturdy muscular restraint. But there will also be those cases where necessity and indication for intervention requiring general anaesthesia will be less clear cut. So what can we as anaesthetists do to minimise the potential of permanent neuro-developmental harm to our youngest patients whilst the concentrated efforts of international studies, GAS (a multi-site randomised controlled trial comparing regional and general anaesthesia for effects on neuro-developmental outcome and apnoea in infants) and PANDA (paediatric anaesthesia neuro-developmental assessment study) hope to shed more light on these worrying findings over the next few years?
We cannot choose safer anaesthetic agents because all volatile and intravenous anaesthetic agents are implicated. It is also unlikely that any new ‘wonder drug’ anaesthetic agent will be produced as there are no new volatile or intravenous anaesthetics even in the earliest stages of R&D - there is simply no commercial drive to develop new anaesthetic agents. We could employ regional anaesthesia a little more, but its role in very young children will always be limited.
About the only immediate action we can take to limit the damage is to anaesthetise only those at risk children who really need surgery. The immediate question is: have we become complacent in not just medicine but society in general, accepting as a ‘means to an easier end’ the welcome safety of modern general anaesthesia? Every anaesthetist will be able to identify in their own practice the numerous cases undergoing ‘safe’ anaesthesia for incredibly minor and even sometimes ‘unnecessary’ procedures. Where do we draw the line, though, if the safety aspect of anaesthesia is under question? Do we, in this era of informed consent and patient empowerment, face a return to more paternalistic decision making in denying general anaesthesia to at risk patients for procedures we professionals regard as ‘unnecessary’?
Though there are still more questions than answers, it behoves all of us to communicate these legitimate concerns to our surgical colleagues and work with them in minimising the number of young children whom we expose ‘unnecessarily’ and repeatedly to general anaesthesia.
The surgeons will also be able to focus their thresholds for intervention more tightly and identify alternative interventions: eg steri strips instead of suturing tiny lacerations; hearing aids instead of grommets until older; investment in education and prevention rather than annual extractions of rotten teeth; leaving tiny moles and skin tags until older, and many more.
Paracelsus may well have been right all along.
[1] Are anaesthetics toxic to the brain? Hudson AE, Hemmings Jr HC. Br J Anaes 2011 doi:10.1093/bja/aer122
[2] Hemmings Jr HC. Personal communication: RCoA Recent Advances in Anaesthesia, Critical Care and Pain; Nottingham 3-5 December 2013
[3] Neurotoxicity of General Anesthetics. Cause for Concern? Perouansky M, Hemmings Jr HC. Anesthesiology 2009; 111(6): 1365-1371. doi:10/ALN.0b013e3181bf1d61
[declaration of interest: Quentin Smith is the author of Huber’s Tattoo, centred around the science of eugenics and engineering human intelligence, pub. February 2014]
