Needle Thoracostomy in the Treatment of a Tension Pneumothorax in Trauma Patients: What Size Needle?

BACKGROUND:A tension pneumothorax requires immediate decompression using a needle thoracostomy. According to advanced trauma life support guidelines this procedure is performed in the second intercostal space (ICS) in the midclavicular line (MCL), using a 4.5-cm (2-inch) catheter (5-cm needle). Previous studies have shown a failure rate of up to 40% using this technique. Case reports have suggested that this high failure rate could be because of insufficient length of the needle. OBJECTIVES:To analyze the average chest wall thickness (CWT) at the second ICS in the MCL in a trauma population and to evaluate the length of the needle used in needle thoracostomy for emergency decompression of tension pneumothoraces. METHODS:Retrospective review of major trauma admissions (Injury Severity Score >12) at the Foothills Medical Centre in Calgary, Canada, who underwent a computed tomography chest scan admitted in the period from October 2001 until March 2004. Subgroup analysis on men and women, 4.5 cm and 24.1% to 35.4% of the women studied. CONCLUSIONS:A catheter length of 4.5 cm may not penetrate the chest wall of a substantial amount (9.9%–35.4%) of the population, depending on age and gender. This study demonstrates the need for a variable needle length for relief of a tension pneumothorax in certain population groups to improve effectiveness of needle thoracostomy.