Do-it-yourself doctoring

Press, 19 May 1981, Page 22

Do-it-yourself doctoring

From “The Economist,” London

What' is the best way to determine the amount of painkiller a patient needs? Give him too little and he will remain in pain. Give him too much and he. may suffer nasty side-effects such as a drop in normal breathing or even addiction.

Because pain is subjective, it is all too easy for doctors to get the dose wrong. So some have come round to the view that it is best to let the patient do the dosing himself. To help the patient treat himself, Dr Chris Hull of the medical school at the University of Newcastle upon Tyne in Britain, has designed a sophisticated device called the On Demand Analgesia Computer (Odac for short). At present, it is intended for the control of pain in postoperative patients (who are nofmallly given narcotic drugs). The patient is attachec to an Odac via an intravenous tube for 24 hours after his operation. About the size of two books and controlled by a microprocessor, the Odac has a tape pre-recorded to ask the-patient at regular intervals (in a suitably sympathetic voice) whether he is in : pain and to instruct him, if so, to push a button for relief.

Not that the patient is left in complete control. The Odac continually administers a certain background dose of the analgesic being used (at Newcastle, the paih-killler fentanyl).'But if the patient presses the button, he is given a predetermined booster dose. The tape in the Odac confirms the dose has been given. The aim is to provide half of the treatment automatically and half on request. The device has numerous built-in checks to make sure it will not continue to operate if malfunctioning. A self-manage-ment system already on the market in Britain — the Cardiff Palliator of Pye Dynamics — is much less elaborate. It simply delivers a drug on the press of a button and its only built-in safeguards are maximum and minimum doses. Odacs are already being used on several hundred patients in clincial trials in Europe, and trials are also planned in,the United States. Results so far have been impressive. Post-operative patients who have used the device seem to have managed pain relief better than physicians, and - there has been little evidence of overdosing. Plans are going ahead to try

the svstem on patients who experience acute episodic pain: e.g., certain heart patients and those suffering from diseases of the pancreas, kidney and intestine.

A trial will also begin soon on patients in chronic pain who have had little relief from their present lt is hoped that their pain will prove more amenable to their own control.