Authors: Nasir Hussain, M.Sc., M.D. et al
Anesthesiology 12 2017, Vol.127, 998-1013.
Background: Interscalene block provides optimal shoulder surgery analgesia, but concerns over its associated risks have prompted the search for alternatives. Suprascapular block was recently proposed as an interscalene block alternative, but evidence of its comparative analgesic effect is conflicting. This meta-analysis compares the analgesic effect and safety of suprascapular block versusinterscalene block for shoulder surgery.
Methods: Databases were searched for randomized trials comparing interscalene block with suprascapular block for shoulder surgery. Postoperative 24-h cumulative oral morphine consumption and the difference in the area under curve for pooled rest pain scores were designated as primary outcomes. Analgesic and safety outcomes, particularly block-related and respiratory complications, were evaluated as secondary outcomes. Results were pooled using random-effects modeling.
Results: Data from 16 studies (1,152 patients) were analyzed. Interscalene block and suprascapular block were not different in 24-h morphine consumption. The difference in area under the curve of pain scores for the 24-h interval favored interscalene block by 1.1 cm/h, but this difference was not clinically important. Compared with suprascapular block, interscalene block reduced postoperative pain but not opioid consumption during recovery room stay by a weighted mean difference (95% CI) of 1.5 cm (0.6 to 2.5 cm; P < 0.0001). Pain scores were not different at any other time. In contrast, suprascapular block reduced the odds of block-related and respiratory complications.
Conclusions: This review suggests that there are no clinically meaningful analgesic differences between suprascapular block and interscalene block except for interscalene block providing better pain control during recovery room stay; however, suprascapular block has fewer side effects. These findings suggest that suprascapular block may be considered an effective and safe interscalene block alternative for shoulder surgery.
What We Already Know about This Topic
- Shoulder surgery is associated with significant postoperative pain, and interscalene block remains a primary form of perioperative analgesia
- There are conflicting data about the value of suprascapular nerve blocks for shoulder surgery
What This Article Tells Us That Is New
- A meta-analysis of 16 studies demonstrates suprascapular block results in 24-h morphine consumption and pain scores similar to interscalene block
- Pain control may be better with interscalene blocks at 1 h postoperation
- Suprascapular block is associated with fewer complications, in particular those that may limit the use of interscalene blocks in patients with obesity, sleep apnea, or pulmonary disease