What is the minimum effective anesthetic volume (MEAV90) of 0.2% ropivacaine required for ultrasound-guided popliteal-sciatic nerve block?

Evaluating the impact of ultrasound-guided subsheath versus extrasheath sciatic nerve block on postoperative wound pain in tibial and foot surgeries: A systematic review and meta-analysis

This systematic review and meta-analysis evaluate the impact of ultrasound-guided subsheath versus extrasheath sciatic nerve blocks on postoperative wound pain in tibial and foot surgeries, crucial for effective pain management and patient recovery. Adhering to PRISMA guidelines, this study used a PICO framework, focusing on patients undergoing tibial and foot surgeries and comparing the efficacy and safety of subsheath and extrasheath sciatic nerve blocks. The literature search spanned four databases without time restrictions, assessing various outcomes like success rate, onset time, duration of analgesia and complication rates. Quality assessment employed the Cochrane Collaboration's risk of bias tool, and statistical analyses included heterogeneity assessment, fixed-effect and random-effects models, sensitivity analysis and publication bias evaluation using funnel plots and Egger's linear regression test. From an initial pool of 1213 articles, six met the inclusion criteria. The subsheath group showed a significantly higher success rate of complete sensory blockade within 30 min compared with the extrasheath group (OR = 5.39; 95% CI: 2.82-10.28; p < 0.01). No significant differences were found in procedure duration or incidence of nerve-related complications between the two techniques. The subsheath approach also demonstrated a quicker onset time of sensory blockade (MD = -8.57; 95% CI: -11.27 to -5.88; p < 0.01). Sensitivity analysis confirmed the stability of the results, and no significant publication bias was detected. Ultrasound-guided subsheath sciatic nerve blocks are more effective than extrasheath blocks in achieving rapid and complete sensory blockade for tibial and foot surgeries, with a quicker onset time and comparable safety profile. Subsheath injections are thus recommended as a preferred method for anaesthesia and postoperative pain management in these surgical procedures, enhancing overall patient outcomes.