Determination of the chest wall thicknesses and needle thoracostomy success rates at second and fifth intercostal spaces: a cadaver-based study

Abstract

IntroductionThe purposes of this study were to measure the chest wall thicknesses (CWTs) at second intercostal space (ICS) mid-clavicular line (MCL) and fifth ICS MAL directly, and compare the actual success rates of needle thoracostomies (NTs) by inserting a 5-cm-long syringe needle. Predictive values of weight, body mass index (BMI) and CWT were also analyzed. Materials and MethodsThis study included 199 measurements of 50 adult fresh cadavers from both hemithoraces. Five-centimeter-long syringe needles were inserted and secured. Penetration into the pleural cavity was assessed, and CWTs at 4 locations were measured. Achieved power of this study for the primary aim of CWT comparison from 2nd and 5th ICSs was .94. ResultsOverall mean CWTs at 2nd ICS MCL and 5th ICS MAL were measured as 2.46 ± 0.78 and 2.89 ± 1.09, respectively, and 5th ICS MAL was found to be statistically thicker (P = .002). The success rate of NT at 2nd ICS MCL was 87% (95% CI, 80-94), and that at 5th ICS MAL was 78% (95% CI, 70-86; P = .3570). Only 6 (17.1%) of 35 failed NTs had a CWT greater than 5-cm. Needle thoracostomy has failed in 29 (14.9%) of 194 locations, despite a CWT less than 5-cm. Below a weight of 72 kg, BMI of 23 kg/m2, or CWT of 2.4 cm, all NTs were successful. Discussion and ConclusionsIn this report, we present the largest cadaver-based cohort to date to the best of our knowledge, and we observed a statistically nonsignificant 9% more NT success rate at 2nd ICS at a power of 88% and statistically significant more success rate in males at 5th ICS was (47.7%). We also observed thinner CWTs and higher success rates than previous imaging-based studies. A BMI of 23 kg/m2 or less and weight of 72 kg or less seem to accurately rule-out NT failure in cadavers, and they seem to be better predictors at the bedside.