I.v. regional diamorphine for analgesia after foot surgery

Opioids administered to peripheral tissues can have significant analgesic effects in doses which would not be effective centrally. We have assessed the effects of regional diamorphine 2.5 mg i.v. in 14 patients undergoing surgical correction of bilateral arthritic foot deformities in a prospective, randomized, double-blind study. Patients acted as their own controls as only one foot received the active drug. Visual analogue scale (VAS) pain scores and wound tenderness were measured over 72 h. Diamorphine did not improve median VAS area under the curve pain scores during the first 6 h after surgery (33 (95% confidence intervals (CI) 25-46) vs 24 (17-35)). It also did not effect wound hypersensitivity when tested at 72 h after surgery (95 (47-125) vs 90 (50-125) g). There were no significant adverse effects.