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Early chest tube removal following cardiac surgery is associated with pleural and/or pericardial effusions requiring invasive treatment.

OBJECTIVES
Different opinions exist as to when chest tube removal should be performed following cardiac surgery. The aim of this study was to compare early chest tube removal with removal of the tubes in the morning day 1 postoperatively. Primary combined end point was the risk of postoperative accumulation of fluid in the pericardial and/or pleural cavities requiring invasive treatment.


METHODS
A retrospective observational cohort study was performed among patients undergoing coronary artery bypass grafting (CABG) and/or conventional valve surgery between July 2010 and June 2013. Patients in whom chest tube output was <150 ml around midnight during the last 4 h were included in the study. These patients were divided into two groups: Group 1 had their chest tubes removed around midnight on the day of surgery, whereas Group 2 kept their tubes until next morning. Using Poisson regression, we estimated crude and adjusted relative risks (RRs) for developing postoperative pleural and/or pericardial effusion within 14 days requiring interventional treatment.


RESULTS
A total of 1232 patients underwent CABG, conventional valve or combined surgery during the study period. Of these, 782 patients fulfilled the criteria for early chest tube removal, which was performed in 385 of the patients. A total of 76 patients in Group 1 (20%) and 51 patients in Group 2 (13%) developed postoperative pleural and/or pericardial effusions requiring invasive treatment (P = 0.011). A positive association between early chest tube removal and the development of pleural and/or pericardial effusions was seen [crude RR: 1.54 (95% CI: 1.11-2.13); adjusted RR: 1.70 (95% CI: 1.24-2.33)]. The association became stronger investigating pleural effusions alone (adjusted RR = 1.77; 95% CI: 1.27-2.46), whereas the association with pericardial effusions was less clear.


CONCLUSIONS
Removal of all chest tubes around midnight on the day of surgery is associated with an increased risk of postoperative pleural and/or pericardial effusions requiring invasive treatment even if chest tube output during the last 4 h is <150 ml compared with removal of the tubes next morning.