A comparison of spinal, epidural, and general anesthesia for outpatient knee arthroscopy.

Abstract

We compared general, epidural, and spinal anesthesia for outpatient knee arthroscopy (excluding anterior cruciate ligament repairs). Forty-eight patients (ASA physical status I-III) were randomized to receive either propofol-nitrous oxide general anesthesia with a laryngeal mask airway with anesthetic depth titrated to a bispectral index level of 40-60, 15-20 mL of 3% 2-chloroprocaine epidural, or 75 mg of subarachnoid procaine with 20 microg fentanyl. All patients were premedicated with <0.035 mg/kg midazolam and <1 microg/kg fentanyl and received intraarticular bupivacaine and 15-30 mg of IV ketorolac during the procedure. Recovery times, operating room turnover times, and patient satisfaction were recorded by an observer using an objective scale for recovery assessment and a verbal rating scale for satisfaction. Statistical analysis was performed with analysis of variance and chi(2). Postanesthesia care unit discharge times for the general and epidural groups were similar (general = 104+/-31 min, epidural = 92+/-18 min), whereas the spinal group had a longer recovery time (146+/-52 min) (P = 0.0003). Patient satisfaction was equally good in all three groups (P = 0.34). Room turnover times did not differ among groups (P = 0.16). There were no anesthetic failures or serious adverse events in any group. Pruritus was more frequent in the spinal group (7 of 16 required treatment) than in the general or epidural groups (no pruritus) (P<0.001). We conclude that epidural anesthesia with 2-chloroprocaine provides comparable recovery and discharge times to general anesthesia provided with propofol and nitrous oxide. Spinal anesthesia with procaine and fentanyl is an effective alternative and is associated with a longer discharge time and increased side effects. For outpatient knee arthroscopy, anesthesia can be provided adequately with regional or general anesthesia. Epidural and general anesthesia provide equal recovery times and patient satisfaction, whereas spinal anesthesia may prolong recovery and have increased side effects. The choice of anesthesia may depend primarily on the patient's interest in being alert or asleep during the procedure.