The Benefit of Ultrasound in Deciding Between Tube Thoracostomy and Observative Management in Hemothorax Resulting from Blunt Chest Trauma.

BACKGROUND: Hemothorax is most commonly resulted from a closed chest trauma, while a tube thoracostomy (TT) is usually the first procedure attempted to treat it. However, TT may lead to unexpected results and complications in some cases. The advantage of thoracic ultrasound (TUS) over a physical examination combined with chest radiograph (CXR) for diagnosing hemothorax1 has been proposed previously. However, its benefits in terms of avoiding non-therapeutic TT have not yet been confirmed. Therefore, this study is aimed to evaluate the severity of hemothorax in blunt chest trauma patients by using TUS in order to avoid non-therapeutic TT in stable cases.

METHODS: The data from 46,036 consecutive patient visits to our trauma center over a four-year period were collected, and those with blunt chest trauma were identified. Patients who met any of the following criteria were excluded: transferred from another facility, with an abbreviated injury scale (AIS) score ≥ 2 for any region except the chest region, with a documented finding of tension pneumothorax or pneumothorax >10%, younger than 16 years old and with indications requiring any non-thoracic major operation. The decision to perform TT for those patients in the non-TUS group was made on the basis of CXR findings and clinical symptoms. The continuous data were analyzed by using the two-tailed Student's t test, and the discrete data were analyzed by Chi-square test.

RESULTS: A total of 84 patients met the criteria for inclusion in the final analysis, with TT having been performed on 42 (50%) of those patients. The mean volume of the drainage amount was 860 ml after TT. The TT drainage was less than 500 ml in 12 patients in the non-TUS group (40%), while none was less than 500 ml in the TUS group (p = 0.036, Fisher's exact test). In terms of the positive rate of subsequent effective TT, the sensitivity of TUS was 90% and the specificity was 100%. There were 3 patients with delayed hemothorax: 2 of the 58 (3.6%) in the non-TUS group and 1 of 26 (4.5%) in the TUS group (p > 0.05, Fisher's exact test). The hospital length of stay in the non-TUS group with non-therapeutic TT was significantly longer than in the TUS group without TT (8.2 vs. 5.4 days, p = 0.018). There were no other major complications or deaths in either group during the 90-day follow-up period.

CONCLUSION: In the case of blunt trauma, TUS can rapidly and accurately evaluate hemothorax to avoid TT in patients who may not benefit much from it. As a result, the rate of non-therapeutic TT can be decreased, and the influence on shortening hospital length of stay may be further evaluated with prospective controlled study.