The analgesic effects of novel fascial plane blocks compared with intrathecal morphine after Caesarean delivery: a systematic review and meta-analysis.

Summary

Across 18 trials (n=1525), intrathecal morphine outperformed TAP blocks for early postoperative pain, whereas quadratus lumborum blocks showed comparable analgesia with fewer opioid-related adverse effects. Evidence for ESP was limited. These findings support QL as a viable intrathecal morphine alternative in multimodal post-Cesarean analgesia.

Key Findings

• Intrathecal morphine provided superior pain relief versus TAP at 6 and 12 hours post-Cesarean.
• Quadratus lumborum blocks achieved comparable analgesia to intrathecal morphine with fewer opioid-related side effects.
• Evidence for erector spinae plane blocks was limited and insufficient to conclude equivalence.
• Secondary outcomes included reduced opioid consumption and timings of mobilization/breastfeeding favoring intrathecal morphine over TAP.

Clinical Implications

For patients at risk of opioid-related side effects or where intrathecal morphine is contraindicated/unavailable, consider quadratus lumborum blocks as an effective alternative; TAP alone may be insufficient for early analgesia compared to intrathecal morphine.

Limitations

• Heterogeneity in block techniques, local anesthetic regimens, and multimodal adjuncts across trials.
• Limited number of ESP studies restricts confident conclusions for this technique.

Future Directions

Conduct high-quality RCTs comparing QL versus intrathecal morphine with standardized protocols, and adequately powered trials evaluating ESP versus QL/IT morphine focusing on maternal and neonatal outcomes.