Computed tomography evaluation of different chest tube sites for residual pleural volumes after coronary artery bypass surgery

BACKGROUND AND OBJECTIVES: We investigated the efficacy of pleural drainage with the use of different chest tube methods in patients after coronary artery bypass graft (CABG) surgery. DESIGN AND SETTING: Prospective randomized study of 60 patients undergoing elective on-pump single CABG surgery. PATIENTS AND METHODS: The left internal mammary arterial grafts were harvested from all patients. The patients were separated into three groups: In one group (IC6, n=20), pleural tubes were inserted through the sixth intercostal space at the midaxillary line; in the second group (SX-r, n=20), rigid straight pleural tubes were inserted from the mediastinum through the subxiphoid area; and in the third group (SX-s, n=20), soft curved drainage tubes were inserted from the mediastinum through the subxiphoid area. The residual pleural effusion was examined by multislice CT scans within 8 hours of removal of the drainage tubes. Pain was evaluated according to standard methods. RESULTS: The groups did not differ with respect to volume of residual pleural effusion (P>.05). The IC6 group had a higher mean pain score than the other two groups (P<.05), whose mean pain scores did not differ significantly from each other (P>.05). IC6 group patients had a higher requirement for analgesics. The rate of atelectasis was higher in group IC6 (P<.05). CONCLUSION: CT scans revealed that different chest tube insertion sites have the same efficiency for draining of pleural effusion, although drainage tubes inserted through the thoracic cage may result in more severe pain.