Improving patients' postoperative sleep: a randomized control study comparing subcutaneous with intravenous patient-controlled analgesia.

One hundred female patients undergoing major reconstructive plastic or gynaecological surgery were randomized to either receive subcutaneous patient-controlled analgesia (PCA) (bolus dose 2.5 mg diamorphine in 1 ml with a 20-minute lockout) or intravenous PCA (bolus dose 0.5 mg diamorphine in 1 ml with a 5-minute lockout). Data were collected by questionnaire and interview to evaluate the intervention on pain scores, quality of sleep on the first postoperative night, postoperative nausea and vomiting (PONV) and overall patient acceptability. The subcutaneous PCA group experienced less 'worse pain' (P < 0.01) and less sleep disturbance due to pain (P < 0.001). Subcutaneous PCA would appear to offer patients a safe and effective means of analgesia and may offer significant advantages over the intravenous route of administration.