Intravenous ketamine anaesthesia for major abdominal surgery--an assessment of a technique and the influence of ataractic drugs on the psychomimetic effects of ketamine.

Eighty-two patients presenting for major abdominal surgery were divided into five groups, and received intravenous ketamine, muscle relaxation and controlled ventilation with oxygen-enriched air. For maintenance of anaesthesia patients were given a single intravenous dose of either droperidol 5 mg, diazepam 5 mg, promethazine 25 mg, flunitrazepam 0.5 mg or lorazepam 2 mg, followed by incremental doses of ketamine. Flunitrazepam and lorazepam were the adjuvants associated with the lowest incidence of dreaming and emergence phenomena; postanaesthetic sequelae occurred most frequently with both ketamine/diazepam and ketamine/droperidol anaesthesia. However, the differences between the five groups failed to reach statistical significance.