Introduction: The preferred chest tube (CT) removal algorithm has not yet been established. The purpose of this study was to determine which technique, water seal or suction, allowed for shorter CT duration. In addition, the recurrent pneumothorax (PTX) rate, the need for CT reinsertion, and the total number of chest x-ray films (CXR) were determined.
Methods: Prospective randomized trial of 205 trauma patients, older than 15 years of age, requiring tube thoracostomy for blunt and penetrating trauma. Patients requiring mechanical ventilation more than 24 hours were excluded from the study. Informed consent was obtained from all patients. Chest tubes were randomized for removal when output was less than 150 mL/24 hours, CXR revealed no significant PTX, and no air leak was present. Patients in the water seal group were disconnected from low wall suction and a CXR was obtained 6 to 8 hours later. Chest tubes in the no water seal group were disconnected from wall suction and pulled immediately. All tubes were removed by using standard protocol with patients at maximal inspiratory effort. A follow-up CXR was obtained after removal.
Results: Of the 205 patients, 93 patients (45 %) were randomized to the water seal group and 112 patients (54%) to the no water seal group. Four patients in the water seal group developed a PTX before CT removal and were considered treatment failures. After CT removal, repeat PTX was seen in 13 patients in the water seal group and in 9 patients in the no water seal group. However, seven patients in the no water seal group required CT reinsertion compared with one in the water seal group (p<0.05). Average number of CXR in the water seal group was 6.5 compared with 5.5 radiographs in the no water seal group. There was no difference in chest tube duration or hospital length of stay between groups for either all patients or only those patients with isolated chest injuries. Patients who required another CT had a hospital length of stay twice that of patients who did not.
Conclusions: It is possible that patients in the no water seal group did not have sufficient time for a possible PTX to evolve, which resulted in a larger and more significant PTX requiring another CT. Although there was no difference in chest tube duration between the no water seal and water seal groups, a short trial of water seal appears to allow occult air leaks to become clinically apparent and reduces the need for another CT.