BACKGROUND: We evaluated the bacteriological contamination of chest drainage liquid under closed system after exchanging the bottle and the solution seal with 12 and 24 hours, in patients with or without antibiotics. METHODS: The fluid of 54 chest drainage, under closed tube thoracostomy,was investigated in 44 patients with closed chest injury or with spontaneous pneumothorax, divided into two groups, in accordance to the interval to replace the physiological serum solution in the collector bottle. In the group A (23 patients, 28 drainages) the exchange of the bottle and of the solution seal was performed every 12 hours and in the group B (21 patients, 26 drainages) every 24 hours. A normal distribution test for the analysis of parametric data and chi-square test for the analysis of no parametric data were used. Pleural empyema and thoracic trauma by firearms or stab were excluded. RESULTS: From 44 patients subjected to chest drainage, 15 (34,2%) presented hemopneumothorax, 13 (29,5%) isolated pneumothorax, six (13,6%) hemothorax, six (13,6%) post-thoracotomy, three (6,8%) by pleural effusions and 1 (2,3%) subcutaneous emphysema. There wasn't significant difference regarding to antibiotic use and the number of positive cultures (eleven in each case) in the two groups, as well as when it was analyzed the number of new positive cases per day in each group (p>0,05). CONCLUSIONS: The analysis of this study confirmed that the replacement of drainage fluid in collector bottle, by sterile physiological serum, in an interval time of 12 or 24 hours, showed no difference in the bacterium colonization index, independent of antimicrobian use.
Suction; Thorax; Antibiotics; Contamination; Bacteria; Evaluation studies
