Patients who are in pain, anxious or acutely disturbed are seen frequently in the accident and emergency department. Good personal management will do much to assist with their treatment, but many patients will require additional treatment with drugs. The word “sedation” is often used generically to encompass relief from both pain (analgesia) and anxiety, but it must be recognised that they are separate processes, even though many patients require both. The therapeutic goals of sedation are relief of anxiety, reduction in psychological stress, and amnesia for procedures or traumatic events. The therapeutic goal of analgesia is to provide relief (complete whenever possible) of pain due to injury or of a potentially painful procedure. It is usually necessary to treat with separate agents to achieve these goals, and it is important to understand the potentially synergistic effects of the drugs used.

All drugs that depress the central nervous system have the potential to produce cardiovascular or respiratory complications. Endoscopy has a reported morbidity rate of 1 in 200 and a mortality of 1 in 2000.¹ These adverse events are closely linked to high doses of sedatives and lack of monitoring. An audit of bronchoscopy practice and sedation in the UK in 1997 found deficiencies in patient monitoring and staff training.² A similar survey of sedation for transoesophageal echocardiography in November 2000 found that 29% of practitioners did not use oximetry, 4% did not even have an oxygen supply in the room and 74% had never received formal training in sedation.³

Although sedation in elective circumstances is clearly challenging, sedation in the emergency department may be further complicated because patients often present in less than ideal circumstances and with comorbidity. Such patients often require immediate interventions and therefore cannot always be thoroughly prepared. A complete medical assessment may not …