External oblique intercostal block provides greatest opioid-sparing effect for laparoscopic sleeve gastrectomy patientsSpecific nerve blocks may reduce opioid use after weight loss surgery

This network meta-analysis evaluated the efficacy of various fascial plane blocks for pain management in adults undergoing laparoscopic sleeve gastrectomy (LSG). The study included a total population of 2,005 patients to compare multiple regional techniques against systemic analgesia (SA), placebo, or port-site infiltration (PSI). The specific interventions analyzed included transversus abdominis plane (TAP) block, erector spinae plane block (ESPB), quadratus lumborum (QL) block, external oblique intercostal (EOI) block, modified thoracoabdominal nerve block via perichondrial approach (M-TAPA), paravertebral block (PVB), and rectus sheath (RS) blocks.

The primary outcome measured was 24-hour opioid consumption in morphine milligram equivalents (MME). The analysis determined that the EOI block achieved the greatest opioid-sparing effect compared to systemic analgesia, with a mean difference of -19.66 MME. This finding was supported by a SUCRA ranking of 83%. However, it is important to note that confidence intervals overlapped with other blocks for the EOI block, and the SUCRA rankings are probabilistic hierarchies rather than definitive proof of superiority.

Secondary outcomes included pain scores at 2 to 24 hours and postoperative nausea and vomiting (PONV). Regarding pain intensity, the ESPB significantly reduced pain intensity at 24 hours with a mean difference of -0.44. In terms of PONV incidence, the QL block was found to significantly decrease PONV compared to placebo, showing an odds ratio of 0.31. These results suggest that different fascial plane blocks may offer specific benefits depending on whether the clinical goal is opioid reduction or the mitigation of side effects like nausea.

Safety and tolerability data indicated that no major block-related adverse events were reported during the study period. Specific rates for serious adverse events or discontinuations were not reported, and general tolerability was not specifically quantified. The lack of major complications suggests these regional techniques are generally well-tolerated in the surgical population.

When compared to previous literature on abdominal surgery, these findings provide specific data for LSG patients rather than general abdominal procedures. While other studies have shown that peripheral nerve blocks can reduce morphine consumption in surgeries like kidney transplants or cesarean sections, this meta-analysis specifically highlights the EOI block as a potent opioid-sparing intervention for gastrectomy. Several methodological limitations were identified. The certainty of evidence ranged from moderate to low across the study. Specifically, several interventions were supported by limited data derived from only one or two trials. Furthermore, the overlapping confidence intervals for the EOI block mean that while it ranked highest in the SUCRA analysis, its superiority over other blocks is not statistically definitive. Additionally, the reduction in pain intensity for ESPB was noted as small (-0.44).

Clinically, these results suggest that technique selection should be guided by specific analgesic goals, local expertise, and individual patient factors. For example, if a clinician's primary goal is to minimize opioid consumption, the EOI block may be preferred. If reducing PONV is a priority, the QL block may be more appropriate. However, because evidence for many of these blocks is limited to only one or two trials, clinicians should exercise caution when implementing these techniques based solely on this meta-analysis.

Several questions remain unanswered regarding the long-term durability of these blocks and their comparative efficacy against other regional techniques not included in this specific network. Further large-scale randomized controlled trials are needed to confirm the superiority of EOI over other fascial plane blocks for LSG patients.