Thoracic needle decompression for tension pneumothorax: Clinical correlation with catheter length

Background: Tension pneumothorax requires emergent decompression. Unfortunately, some needle thoracostomies (NTs) are unsuccessful because of insufficient catheter length. All previous studies have used thickness of the chest wall (based on cadaver studies, ultrasonography or computed tomography [CT]) to extrapolate probable catheter effectiveness. The objective of this clinical study was to identify the frequency of NT failure with various catheter lengths. Methods: We evaluated the records of all patients with severe blunt injury who had a prehospital NT before arrival at a level-1 trauma centre over a 48-month period. Patients were divided into 2 groups: Helicopter (4.5-cm catheter sheath) and ground ambulance (3.2 cm) transport. Success of the NT was confirmed by the absence of a large pneumothorax on subsequent thoracic ultrasonography and CT. Results: Needle thoracostomy decompression was attempted in 1.5% (142/9689) of patients. Among patients with blunt injuries, the incidence was 1.4% (101/7073). Patients transported by helicopter (74%) received a 4. 5-cm sheath. The remainder (26% ground transport) received a 3. 2-cm catheter. A minority in each group (helicopter 15%, ground 28%) underwent immediate chest tube insertion (before thoracic ultrasound) because of ongoing hemodynamic instability. Failure to decompress the pleural space by NT was observed via ultrasound and/or CT in 65% (17/26) of attempts with a 3.2-cm catheter, compared with only 4% (3/75) of attempts with a 4. 5-cm catheter (p < 0.001). Conclusion: Tension pneumothorax decompression using a 3. 2-cm catheter was unsuccessful in up to 65% of cases. When a larger 4.5-cm catheter was used, fewer procedures (4%) failed. Thoracic ultrasonography can be used to confirm NT placement.