Peripheral nerve blocks result in superior recovery profile compared with general anesthesia in outpatient knee arthroscopy

Abstract

It has been suggested that use of peripheral nerve blocks (PNBs) may have some potential benefits in the outpatient setting. There have been no studies specifically comparing PNBs performed with short-acting local anesthetics with general anesthesia (GA) in patients undergoing outpatient knee surgery. We hypothesized that a combination of lumbar plexus and sciatic blocks using a short-acting local anesthetic will result in shorter time-to-discharge-home as compared with GA. Patients scheduled to undergo knee arthroscopy were randomized to receive a GA (midazolam, fentanyl, propofol, N(2)O/O(2)/desflurane via laryngeal mask airway) or lumbar plexus/sciatic block (PNBs; 2-chloroprocaine). Patients given GA also received an intraarticular injection of 20 mL 0.25% bupivacaine for postoperative pain control. Patients in the PNB group were given midazolam (up to 4 mg) and alfentanil (500-750 microg) before block placement and propofol 30-50 microg . kg(-1) . min(-1) for intraoperative sedation. Relevant perioperative times, postanesthesia care unit bypass rate, severity of pain, and incidence of complications were compared between the two groups. Fifty patients were enrolled in the study; 25 patients each received GA or PNBs. Total operating room time did not differ significantly between the 2 groups (97 +/- 37 versus 91 +/- 42 min). Seventy-two percent of patients receiving PNB met criteria enabling them to bypass Phase I postanesthesia care unit compared with only 24% of those receiving GA (P < 0.002). Time to meet criteria for discharge home (home readiness) and time to actual discharge were significantly shorter for patients given PNBs than for patients given GA (131 +/- 62 versus 205 +/- 94 and 162 +/- 71 versus 226 +/- 96, respectively). Under the conditions of our study, the combination of lumbar plexus and sciatic blocks with 2-chloroprocaine 3% was associated with a superior recovery profile compared with GA in patients having outpatient knee arthroscopy.