Determination of the appropriate catheter length for needle thoracostomy by using computed tomography scans of trauma patients in Japan.

Background: Previous studies reported a high failure rate in relieving tension pneumothorax by needle thoracostomy, because the catheter was not sufficiently long to access the pleural space. The Advanced Trauma Life Support guideline recommends needle thoracostomy at the second intercostal space in the middle clavicular line using a 5.0-cm catheter, whereas the corresponding guideline in Japan does not mention a catheter length. It is necessary to measure the chest wall thickness (CWT) and determine the appropriate catheter length taking the differences of habitus in race and region into consideration. This study was designed to analyse CWT in Japanese trauma patients by computed tomography and to determine the percentage of patients whose pleural space would be accessible using a 5.0-cm catheter.

Patients And Methods: We performed a retrospective review of chest computed tomography of 256 adult Japanese trauma patients who were admitted to the level 1 trauma centre of Tokai University Hospital in Kanagawa, Japan between January and July 2008. In 256 patients, the CWT at 512 sites (left and right sides) was measured by chest computed tomography at the second intercostal space in the middle clavicular line. The frequency of measurement sites <5.0 cm was calculated simultaneously. The samples were divided according to gender, side (left and right), abbreviated injury scale (<3, ≧3), arm position during examination (up/down), and the existence or non-existence of associated injuries (pneumothorax, subcutaneous emphysema, and fracture of the sternum and ribs); the CWT of each group was compared.

Results: The mean CWT measured in 192 males and 64 females was 3.06±1.02 cm. The CWT values at 483 sites (94.3%) were less than 5.0 cm. The CWT of females was significantly greater than that of males (3.66 cm vs. 2.85 cm, p<0.0001), and patients with subcutaneous emphysema had greater CWTs than those without it (4.16 cm vs. 3.01 cm, p<0.0001).

Conclusion: The mean CWT at the second intercostal space in the middle clavicular line was 3.06 cm. It is likely that over 94% of Japanese trauma patients could be treated with a 5.0-cm catheter.