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Background:Regional nerve blocks are commonly used to manage postoperative pain after arthroscopic shoulder procedures. The interscalene brachial plexus block (ISB) is commonly used; however, because of the reported side effects of ISB, the use of a suprascapular nerve block (SSNB) has been described as an alternative strategy with fewer reported side effects.Purpose:To examine the efficacy of SSNB for pain control after shoulder arthroscopy compared with ISB as well as anesthesia without a nerve block.Study Design:Systematic review; Level of evidence, 1.Methods:Three databases (PubMed, MEDLINE, and EMBASE) were searched on April 20, 2018, to systematically identify and screen the literature for randomized controlled trials (RCTs). A meta-analysis of standard mean differences (SMDs) was performed to pool the estimated effects of the nerve blocks.Results:The search identified 14 RCTs that included 1382 patients, with a mean age of 54 years (SD, 13 years). The mean follow-up time was 3 days (range, 24 hours to 6 weeks). Postoperative pain control was significantly more effective in the SSNB groups compared with the control groups within 1 hour (SMD, –0.76; 95% CI, –1.45 to –0.07; P = .03) and 4 to 6 hours (SMD, –0.81; 95% CI, –1.53 to –0.09; P = .03) postoperatively. However, pain control was significantly less effective in the SSNB groups compared with ISB within 1 hour (SMD, 0.87; 95% CI, 0.28 to 1.46; P = .004). No major complications were noted in the SSNB groups, and minor complications such as hoarseness and prolonged motor block were significantly less common for SSNB compared with ISB.Conclusion:Although not more efficacious than ISB in terms of pain control for patients undergoing shoulder arthroscopy, SSNB provides significantly improved pain control in comparison with analgesia without a nerve block. Moreover, few major and minor complications are associated with SSNB reported across the literature.

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To date, ischemic preconditioning is regarded as the most powerful form of endogenous myocardial protection. For the purpose of surgical myocardial protection, a few clinical studies have investigated the effects of ischemic preconditioning in conjunction with hypothermia or blood cardioplegia during open heart surgery, but the results were controversial. We now tested the hypothesis that preconditioning improves myocardial protection in patients undergoing cold crystalloid cardioplegic arrest. 36 patients needing mitral prosthetic valve replacement for rheumatic heart disease were studied. Patients were evenly divided into two groups at random. Preconditioning was elicited by two cycles of 3 minutes ischemia by occlusion of vena cava and aortic cross-clamping followed by 2 minutes reperfusion under cardiopulmonary bypass. All hearts were arrested using 4 degrees C St. Thomas' Hospital solution before the intracardiac operative program. Myocardial protective effects were mainly assessed by electrocardiac activities, leakage of myocardial enzymes, myocardial contractility, and early postoperative recovery. The results indicated that there was a significant reduction of ST-segment shifting (ST-segment elevation, 0.07 +/- 0.02 vs 0.22 +/- 0.07 mV, p < 0.05, at 4 hours post reperfusion) and smaller release of creatine kinase-MB (87 +/- 11.5 vs 143 +/- 17.2 IU/L, p < 0.05, at 12 hours post reperfusion) in the preconditioning group. Preconditioning also enhanced myocardial contractility (dp/dtmax = 1490 +/- 75 vs 1280 +/- 88 mmHg/sec, at 30 minutes post reperfusion, p < 0.05) and promoted early postoperative recovery. The present study suggests that ischemic preconditioning reduces ischemia-reperfusion injury in human hearts even when combined with cold crystalloid cardioplegia.