Meta-analysis of the optimal needle length and decompression site for tension pneumothorax and consensus recommendations on current ATLS and ETC guidelines.

Background
Tension pneumothorax (TP) is a life-threatening condition. The immediate recommended management is needle decompression (ND), followed by the insertion of an intercostal chest drain. The European Trauma Course (ETC) and the Advanced Trauma Life Support (ATLS) guidelines differ on needle size and decompression site, creating clinical uncertainty. This meta-analysis aims to explore the optimal approach for emergency needle decompression in TP.Methods
This meta-analysis followed the PRISMA 2020 guidelines. It included English-language RCTs, cohort, case-control, cross-sectional studies, and case series with more than six patients. Studies on adults undergoing needle decompression therapy for TP or with chest wall thickness measurements were included. Ovid MEDLINE, Embase, and Web of Science databases were searched until May 31, 2024. Data were extracted, assessed for quality using OCEBM and GRADE, and analyzed using SPSS and OpenMeta with random-effects models.Primary Outcome
needle decompression failure rate.Secondary Outcomes
patient demographics, cannula size, and chest wall thickness comparisons.Results
This review analyzed 51 studies on needle decompression for TP, with a weighted mean patient age of 36.67 years. Radiological data from 24 studies (n = 8046) indicated a 32.84% failure rate for needle penetration into the pleural cavity (I2: 99.72%). Increased needle length reduced failure rates by 7.76% per cm. No significant differences in chest wall thickness between genders were observed (T-test, p = 0.77), but thickness at the 5th anterior axillary line (5AAL) and 5th midaxillary line (5MAL) was less than at the 2nd midclavicular line (2MCL). Injury rates were higher at 5AAL than 5MAL, with strong positive correlations between needle length and injury at these sites (0.88, 0.91).Conclusion
Based on our meta-analysis, a 7 cm needle may be appropriate for decompression of right-sided tension pneumothorax at either the 5th intercostal space along the midaxillary line or the 2nd intercostal space along the midclavicular line. For left-sided cases, given the potential risk of cardiac injury, the 2nd midclavicular line is a safer option. However, these recommendations should be interpreted with caution due to considerable heterogeneity among the included studies, potential risk of bias, and variability in measurement techniques. Clinical decisions should always be individualized, taking into account patient-specific factors.