UC San Diego

Background

This randomized, double-blinded, placebo-controlled study investigated the efficacy of patient-controlled regional analgesia using a sciatic perineural catheter in the popliteal fossa and a portable infusion pump for outpatients having moderately painful, lower extremity orthopedic surgery.

Methods

Preoperatively, patients (n = 30) received a sciatic nerve block and perineural catheter in the popliteal fossa. Postoperatively, patients were discharged with both oral opioids and a portable infusion pump delivering study solution (0.2% ropivacaine or 0.9% saline) via the catheter for 3 days. Investigators and patients were blinded to random group assignment. Daily end-points included pain scores, opioid use and side effects, sleep quality, and symptoms of catheter- or local anesthetic-related complications.

Results

Ropivacaine (n = 15) infusion significantly reduced pain compared with saline (n = 15) infusion ( < 0.001). For example, the average pain at rest (scale: 0-10) on postoperative day 1 (median, 25th -75th percentile) was 4.0 (3.5-5.5) for the saline group, versus 0.0 (0.0-0.0) for the ropivacaine group (P < 0.001). Oral opioid use and related side effects were significantly decreased in the ropivacaine group. For example, on postoperative day 1, median tablet consumption was 8.0 (5.0-10.0) and 0.0 (0.0-0.0) for the saline and ropivacaine groups, respectively (P < 0.001). Sleep disturbance scores were more than 10-fold greater for saline administration than for ropivacaine infusion (P < 0.001). Overall satisfaction was significantly greater in the ropivacaine group. Other than two inadvertent catheter dislodgements, no catheter- or local anesthetic-related complications occurred.

Conclusions

After moderately painful orthopedic surgery of the lower extremity, ropivacaine infusion using a portable mechanical pump and a popliteal sciatic perineural catheter at home decreased pain, opioid use and related side effects, sleep disturbances, and improved overall satisfaction.