Pethidine in emergency departments: promoting evidence-based prescribing

To the Editor: We congratulate Kaye and colleagues on their efforts to educate and influence prescribing practice in reducing the use of pethidine.1 The adverse effects of pethidine and its lack of efficacy over other opiates have been known and taught since the early 1990s.2 A decade on, we are still seeing significant use of this drug,3 which has multiple disadvantages when compared with other opioid analgesics.

The difficulty lies in doctors’ attitudes to quality improvement and change in health care. It has been noted that doctors’ responses to concern about the quality of health care range widely, from opposition to whole-heartedly embracing legitimate opportunities for improvement.4 While there is such variance, the implementation of evidence-based medicine into practice will lag, sometimes by decades, resulting in unnecessary adverse effects in patients.

With clinical guidelines in place, a rigorous education campaign and many hours of research time and resources, Kaye and colleagues have significantly reduced, but not eradicated, pethidine prescribing in New South Wales. In comparison, O’Connor et al report combining a similar educational program with formulary restrictions to effectively eliminate the use of meperidine (pethidine) in their single centre study.5 We can only conclude that clinical evidence, even when combined with quality improvement campaigns, remains less effective than policy changes which restrict doctors’ behaviour.

From available evidence, the liberal use of pethidine may cause adverse effects which are preventable by a simple system-oriented approach — in this case, the appropriate risk-management step is restricting pethidine use to very limited situations. We cannot continue to justify use of a drug with poor efficacy, toxicity and serious drug interactions.

Pethidine prescribing as a percentage of total narcotics in Launceston General Hospital emergency department, 1992–2004

Note: data not available for some quarters.