Subacromial analgesia via continuous infusion catheter vs. placebo following arthroscopic shoulder surgery: a systematic review and meta-analysis of randomized trials

Abstract

Background: Subacromial analgesia (SAA) is hypothesized to reduce pain after arthroscopic shoulder surgery by delivering a continuous infusion of local anesthetic directly to the surgical site. The purpose of this systematic review and meta-analysis was to evaluate the efficacy of SAA vs. placebo for pain relief after arthroscopic subacromial shoulder procedures.

Methods: MEDLINE, Embase, PubMed, and the Cochrane Central Register of Controlled Trials were searched for randomized controlled trials comparing SAA with placebo after arthroscopic shoulder surgery. Outcomes collected included pain scores (converted to equivalent ordinal visual analog scores; minimal clinically important difference 1.4 cm), oral morphine equivalents used postoperatively, and catheter-related complications. Meta-analysis was performed via a random-effects model. Included trials underwent a risk of bias and quality of evidence assessment.

Results: Nine studies involving 459 participants were included. There were no clinically significant changes for pain scores in SAA at 6-, 12-, 24-, and 48-hour postoperative timepoints. Patients receiving SAA used less morphine equivalents of pain medication at 12 hours only (-0.37 mg, 95% confidence interval: -0.63 to -0.11), but there was no significant difference at 24 and 48 hours. There were no major complications (infection or reoperation). Included trials demonstrated a moderate risk-of-bias, and low to very low quality of evidence for primary outcomes.

Conclusion: Subacromial continuous infusion of local anesthetic does not provide a clinically significant benefit compared with placebo as part of a multimodal analgesia regime after arthroscopic subacromial surgical procedures. Future, high-quality trials are required to further assess the efficacy of SAA against placebo.

Keywords: Arthroscopy; anesthesia; local anesthesia; regional; rotator cuff injuries; shoulder; shoulder impingement syndrome; shoulder pain.