A simple system for patient-controlled analgesia

A simple system for patient-controlled analgesia made from disposable items and using hydrostatic pressure for its driving force is described. The system has been used in 200 patients undergoing intra-abdominal gynaecological surgery who were supervised in a general ward. Morphine was used as the analgesic in 150 patients and pethidine in 50. In the morphine group, analgesia was inadequate in eight and use was discontinued in a further 20 patients for various reasons. In the remaining 122, the system worked well and the majority of patients obtained satisfactory analgesia. Details of analgesic administration and requirements, pain and sedation assessments, and patient appreciation in 50 patients are given. In the group receiving pethidine, analgesia was unsatisfactory in two and use was discontinued in eight. The 24-h consumption of pethidine in 20 patients is recorded together with FVC and FEV1 changes and linear analogue scores for pain. It is suggested that the system provides a means of making the benefits of patient-controlled analgesia more widely available.