Patient-controlled versus nurse-controlled pain treatment after coronary artery bypass surgery

Background: Pain after coronary artery bypass surgery persists for several days. A continuous intravenous infusion of an opioid adequately accomplishe s good pain control in the intensive care unit, but it is often not suitabl e on the ordinary ward. Patient-controlled analgesia (PCA) with intermitten t injections delivered by one of the new devices now available could be an alternative to conventional nurse-controlled analgesia (NCA) based on inter mittent injections. The aim was to compare these two techniques with respec t to efficacy and the amount of opioid used. Methods: Forty-eight patients randomly received PCA or NCA with ketobemidon e following extubation after coronary artery bypass grafting. Drug consumpt ion, pain assessment with the visual analogue score (VAS) and possible side effects were evaluated from extubation to the end bf the second postoperat ive day. Results: On the day of surgery the VAS scores did not differ between the gr oups. From the afternoon of the first postoperative day the VAS scores were higher in the NCA group with mean values at 3-4 out of 10 as compared with mean values around 2 in the PCA group (P<0.01). During the study period th e patients in the PCA group received more ketobemidone as compared with the NCA group, 61.9+/-24.0 mg and 36.3+/-20.2 mg, respectively (P<0.01). Addit ional oral analgesics were used in 12 of the patients in the NCA group comp ared with none in the PCA group. The few side effects reported were equally distributed between the two groups. Conclusion: PCA treatment after coronary artery bypass surgery resulted in better pain treatment and the use of more opioid without an increase in sid e effects compared with traditional NCA treatment.