Intercostal Nerve Block in Supine Position for Urgent Tube Thoracostomy in Trauma Patients: A Randomized-Controlled Study

Introduction: Tube thoracostomy is one of the most painful procedures for trauma patients. Therefore, we aimed to evaluate the effectiveness of a variation of intercostal nerve block in the posterior axillary line in the supine position for trauma patients who are candidates for urgent chest tube insertion. Methods: For this randomized controlled study, normotensive and conscious trauma patients needing urgent chest tube insertion, admitted to Shahid Beheshti Hospital of Kashan from May 2023 until September 2024, were enrolled. Based on the sample size of 20 per group, 40 patients were included and allocated using 4-block randomization to the control group (n = 20), receiving only local anesthesia, and the intervention group (n = 20), receiving local anesthesia with the addition of a modified intercostal block with lidocaine in the posterior axillary line in the supine position. Pain intensity was assessed using the Visual Analogue Scale during and 1 hour after the procedure. One-way analysis of variance was used for normally distributed continuous variables, while the Mann-Whitney U test was used for non-normally distributed continuous variables. Comparisons of categorical variables were performed using the χ2 test or the Fisher test, as appropriate. P < 0.05 was considered statistically significant. Clinical significance was defined as a decrease of ≥ 1 point on the VAS for pain. Results: Forty patients with a mean age of 41.1 ± 1 6.06 years , including 30 males (75%), completed the study. The Visual Analogue Scale Score for pain during the procedure was 8.26 in the intervention group, compared with 9.05 in the control group, indicating a non-significant reduction of 0.79 in pain intensity (P-value = 0.17). The Visual Analogue Scale Score for pain one hour after the procedure was 5.57 in the intervention group, compared with 6.63 in the control group, indicating a small but clinically relevant reduction of 1.06 (P-value = 0.07). Conclusion: A modified intercostal block in the posterior axillary line is feasible in the emergency room, technically simple, and can provide a modest decrease in pain after chest tube insertion. Higher efficacy might be achievable through ultrasound guidance or by simultaneously blocking the collateral branch of the intercostal nerve at the superior border of the ribs.