A randomized comparison between interscalene and combined infraclavicular-suprascapular blocks for arthroscopic shoulder surgery

摘要

Abstract Background This randomized trial aimed to evaluate combined infraclavicular-suprascapular blocks (ICB-SSBs) as a diaphragm-sparing alternative to interscalene blocks (ISBs) for arthroscopic shoulder surgery. We hypothesized that ICB-SSB would provide equivalent postoperative analgesia to ISB 30 min after surgery without the risk of hemidiaphragmatic paralysis. Methods Following research ethics board approval and written informed consent, participants in the ISB group received an ultrasound-guided ISB with 20?mL of levobupivacaine 0.25% and epinephrine 5?μg·mL ?1 . In the ICB-SSB group, ultrasound-guided ICB (20?mL) and SSB (10?mL) were carried out using the same local anesthetic. Thirty minutes after the block was performed, a blinded investigator assessed the presence of hemidiaphragmatic paralysis. Subsequently, all patients underwent general anesthesia. Postoperatively, a blinded investigator?recorded?pain scores at rest at 0.5, 1, 2, 3, 6, 12 and 24?hr.?Consumption of intra- and postoperative narcotics was?also tabulated. Results Compared to its ICB-SSB counterpart, the ISB group displayed non-equivalent (i.e., lower) postoperative pain scores at 30 min (difference of the medians, ?4; 99% confidence interval [CI], ?6 to ?3), required less cumulative morphine iv at 24 hr (difference of the means, ?6.1 mg; 95% CI, ?10.5 to ?1.6), and resulted in a higher incidence of hemidiaphragmatic paralysis (18/20 vs 0/20 patients, respectively; P ? Conclusion Compared with ICB-SSB, ISB provided non-equivalent (i.e., lower) postoperative pain scores 30 min after arthroscopic shoulder surgery. Thereafter, postoperative analgesia was comparable between the two groups. Further trials are required to compare ISB with ICB-SSB using a proximal (i.e., costoclavicular) technique for ICB. Trial registration www.clinicaltrials.gov , NCT02993939. Registered 12 December 2016.