Objective: 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 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 included. According to the sample size of 20 per group, 40 patients were included and allocated per 4-block randomization to the control group (n=20), receiving only local anesthesia and the intervention group (n=20), receiving local anesthesia with addition of a modified intercostal block with lidocaine in the posterior axillary line in supine position. Pain intensity was assessed via Visual Analogue Scale for pain during and one hour after the procedure. One-way analysis of variance was used for normally distributed continuous variables, while Mann-Whitney-U test was used for non-normally distributed continuous variables. Comparisons of categorical variables were performed using χ2 test or Fisher test as appropriate. P < .05 was considered statistically significant. Clinical significance was defined as a decrease of ≥ 1 point in VAS for pain.
Results: Forty patients completed the study with a mean age of 41.1±16.06 years, including 30 males (75%). Visual Analogue Scale Score for pain during the procedure was 8.26 in the intervention group in comparison to 9.05 in the control group, showing a non-significant reduction of 0.79 in pain intensity (p-value=0.17). Visual Analogue Scale Score for pain one hour after the procedure was 5.57 in the intervention group in comparison to 6.63 in the control group, showing 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 of pain after chest tube insertion. Higher efficacy might be achievable with adding ultrasound guidance or simultaneous block of the collateral branch of the intercostal nerve in the superior border of the ribs.