Comparison of continuous epidural infusion of ropivacaine and sufentanil with intravenous patient-controlled analgesia after total hip replacement

We assessed the efficacy of an epidural infusion of ropivacaine 0.1% and sufentanil 1 mug.ml(-1), comparing it with intravenous patient-controlled analgesia using piritramide in this prospective, randomised, double-blind study of 24 ASA physical status I-III patients undergoing elective total hip replacement. Lumbar epidural block using ropivacaine 0.75% was combined with either propofol sedation or general anaesthesia for surgery. Epidural infusion and patient-controlled analgesia were started after surgery. Twelve patients received an epidural infusion of ropivacaine 0.1% and sufentanil 1 mug.ml(-1) at a rate of 5-9 ml.h(-1) and an intravenous patient-controlled analgesia device loaded with saline. Eleven patients received an epidural infusion of saline at the same rate and intravenous piritramide via the patient-controlled analgesia device. Motor block was negligible in both groups. The epidural ropivacaine group had significantly lower visual analogue pain scores at rest 4 h after surgery (p < 0.01), and on movement 4 h (p < 0.01) and 8 h (p < 0.05) after surgery, than the intravenous piritramide group. The piritramide group experienced significantly more adverse events than the epidural group (p < 0.001), especially hypotension (p < 0.01) and vomiting (p < 0.05). Patients in the epidural ropivacaine group were more satisfied with the pain management (p < 0.05). We conclude that the epidural infusion of ropivacaine 0.1% and sufentanil 1 <mu>g.ml(-1) is superior to intravenous opioid by patient-controlled analgesia in preventing pain after total hip replacement, with fewer adverse effects and greater patient satisfaction.