Rectus sheath and transversus abdominis plane blocks in children: a systematic review and meta-analysis of randomized trials.

INTRODUCTION The role of rectus sheath blocks (RSB) and transversus abdominis plane (TAP) blocks in pediatric surgery has not been well established. OBJECTIVE We aimed to determine if RSB and TAP blocks decrease postoperative pain and improve recovery in children. DATA SOURCES Duplicate searching of MEDLINE, EMBASE, Cochrane, Web of Science, and trial registries databases by two reviewers. STUDY SELECTION Included were randomized trials in children on RSB or TAP block in abdominal operations, excluding inguinal procedures. DATA EXTRACTION Independent duplicate data extraction and quality assessment using a standardized form. RESULTS Ten trials met inclusion criteria (n = 599), RSB in five and TAP block in five. A linear mixed effects model on patient level data from three trials showed nerve blocks lowered morphine requirements 6-8 h after surgery, -0.03 mg · kg(-1) (95% CI -0.05, -0.002). Pooled analysis of summary data showed nerve blocks lowered 0-10 scale pain scores immediately after the operation, -0.7 (95% CI -1.3, -0.1); lowered 4-16 scale pain scores, -2.0 (95% CI -2.3, -1.7); and delayed the time to first rescue analgesia, 17 min (95% CI 1.3, 33). Quality assessment showed some studies at moderate to high risk of bias. CONCLUSION Abdominal wall blocks reduce pain and opiate use in children. We advise cautious interpretation of the results given the heterogeneity of studies.