Editorials

Opiate detoxification under anaesthesia

BMJ 1997; 315 doi: http://dx.doi.org/10.1136/bmj.315.7118.1249 (Published 15 November 1997) Cite this as: BMJ 1997;315:1249

Enthusiasm must be tempered with caution and scientific scrutiny

  1. John Strang, Directora,
  2. Jenny Bearn, Consultant psychiatrista,
  3. Michael Gossop, Head of researcha
  1. a National Addiction Centre, The Maudsley Institute of Psychiatry, London SE5 8AF

    At least 10 000 opiate misusers have recently undergone a new detoxification treatment in which acute provocation of withdrawal by opiate antagonists is administered under the cover of a general anaesthetic.1 2 3This technique has been variously hailed as a revolutionary breakthrough or condemned as exploitation of the addicts and their families. While neither the antagonist provocation nor the use of a general anaesthetic is new the combination has apparently captured the imagination of some clinicians, misusers and their families, and commercial interests—the treatment is available only in the private sector and is expensive.

    Much of the controversy has been generated by competing claims of effectiveness and competence from rival providers. Anyone trying to make an objective assessment has been hampered by the lack of information about techniques and of any independent evaluation.3 Indeed, the starting position should be that this technique needs to be shown to produce clear cut benefits sufficient to offset its inherent dangers.4 These include both the hazards of prolonged general anaesthesia and those that must result from the sudden pharmacological bombardment with an opiate antagonist—as well as adrenergic agonists, antiemetics, and antidiarrhoeal agents.

    The “new” detoxification procedure has a history dating back a century to attempts to achieve painless detoxification under general anaesthesia. This was followed in the 1960s and 1970s by the use of deep narcosis. In practice, the anaesthetic is unlikely to provide anything more than a means of bypassing the distress of withdrawal, though that will contribute to the acceptability of the procedure.

    The development of antagonist-precipitated rapid detoxification has a separate ancestry. Since the early 1970s attempts have been made to use naloxone (without an anaesthetic but sometimes with deep sedation) to achieve more rapid detoxification.5 6 7 8Injections of naloxone provoke an immediate severe withdrawal response, but this severity seems to decrease steadily as the doses of naloxone are repeated. Within 48 hours further injections of naloxone no longer provoke substantial withdrawal symptoms. Protocols for a combination of clonidine and naltrexone were developed during the 1980s.9 10These paved the way for studies by Loimer in Vienna in the late 1980s using general anaesthesia to cover the carefully monitored use of naloxone to precipitate detoxification11 12 13—techniques which form the basis for the methods used today by others.

    This new technique seems to have two potential advantages which warrant careful consideration. Firstly, misusers fear detoxification14 and may be more willing to undergo detoxification if they can avoid the acute withdrawal discomfort traditionally associated with it and perhaps also the longer term symptoms of fatigue, dysthymia, and poor sleep.15 Assessment of these outcomes must, however, be rigorous enough to identify which benefits are truly associated with the technique and which are a Hawthorne effect associated with the novelty and mystery of the new procedure. Secondly, the new procedure is said to lead to better completion rates. Plainly, a procedure which anaesthetises the patient will have high completion rates, but the crucial question is whether this benefit carries through to stable abstinence. Greatly improved long term abstinence rates may be due to selection bias, with patients with a good prognosis being the ones willing to seek and pay for the treatment. Another factor might be the supervised treatment with naltrexone after detoxification.

    Any assessment of the claims made for the procedure will need to include the possible disadvantages—which seem likely to be substantially greater than with existing standard detoxification methods. As well as the hazards of prolonged general anaesthesia, high doses of naloxone or naltrexone may occasionally lead to life threatening adverse reactions.16 These hazards might be expected to be even greater if anaesthetic detoxification were attempted in existing drug treatment programmes, whose staff lack the training and experience to care for patients during anaesthetic and recovery periods. Life threatening atypical reactions4 and several deaths have now been reported during, or immediately after, such procedures. Mortality and morbidity will presumably be likely to be even greater among patients with concurrent dependence on alcohol or benzodiazepines or liver disease. More generally, the apparent simplicity of this new detoxification method may lead to misusers, their families, and their carers failing to appreciate the longer term nature of the problem. Finally, the reported ease of detoxification could even lead to unexpected adverse effects such as possible increased initiation into heroin use.

    New detoxification methods which have important and unavoidable hazards should not be made widely available until reliable data are available from controlled studies. Addiction causes such major distress to patients, family, and carers that they will understandably search for new treatments which promise great benefit without risk. The medical and scientific communities have a responsibility to ensure that any new procedures are described accurately and that rigorous studies are made of the benefits and hazards. The lack of such information about anaesthetic detoxification remains disappointing, prevents rational decision making about the justifiability of this new approach, and is a damning indictment of the medical and scientific communities so far. Until there is adequate evidence of effectiveness and safety for this technique it should be used only in clinical trials.

    References

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