Efficacy and safety of interscalene block combined with general anesthesia for arthroscopic shoulder surgery: A meta-analysis.

STUDY OBJECTIVE: There is controversy regarding the efficacy and safety of using interscalene block (ISB) combined with general anesthesia (GA) for arthroscopic shoulder surgery. Our meta-analysis was undertaken to evaluate the utility of this approach.

MEASUREMENTS: We searched the PubMed, Cochrane Library, EMBASE, CNKI, VIP and ClinicalTrials.gov databases for randomized controlled trials. The primary endpoint was extubation time. Secondary endpoints included intraoperative heart rate, pain scores on the day of and 1 day after the operation, intraoperative systolic blood pressure and adverse events.

MAIN RESULTS: Ten RCTs involving 746 patients undergoing arthroscopic shoulder surgery met inclusion criteria. Compared with GA alone, ISB + GA was associated with a shorter extubation time(WMD = -6.13; 95% CI = -8.68 to -3.57; P < 0.00001; I2  = 94%), a lower pain score on the day of the operation (WMD = -2.46; 95% CI = -4.53 to -0.40; P = 0.02; I2  = 97%), a lower pain score 1 day after the operation (WMD = -1.49; 95% CI = -2.46 to -0.52; P = 0.003; I2  = 88%), a lower intraoperative systolic blood pressure (WMD = -12.64; 95% CI = -20.90 to -4.39; P = 0.003; I2  = 95%), a lower heart rate (WMD = -8.81; 95% CI = -15.34 to -2.28; P = 0.008; I2  = 95%) and a lower incidence of adverse events (RR = 0.31; 95% CI = 0.15-0.66; P = 0.002; I2  = 32%).

CONCLUSIONS: In patients undergoing arthroscopic shoulder surgery, ISB + GA is associated with a lower heart rate, lower pain scores on the day of and 1 day after the operation, a lower intraoperative systolic blood pressure, a shorter extubation time and a lower incidence of adverse events compared with GA alone.