Sub-xyphoid pleural drain as a determinant of functional capacity and clinical results after off-pump coronary artery bypass surgery: a randomized clinical trial

OBJECTIVES: the aim of this trial was to compare functional capacity, pulmonary shunt fraction and clinical outcomes between patients undergoing pleurotomy with a pleural drain inserted in the sub-xyphoid position and patients with a pleural drain placed in the intercostal position after off-pump coronary artery bypass surgery.METHODS: Patients were randomized into two groups according to the pleural drain site: Group II (n = 33 intercostal pleural drain); and Group SI (n = 35 sub-xyphoid pleural drain). Functional capacity was assessed by the distance covered on the 6-min walking test performed preoperatively and on postoperative day (POD) 5; in addition, pulmonary function test was determined preoperatively and on POD 1 and 5. Pulmonary shunt fraction was evaluated preoperatively and on POD 1, and clinical outcomes were recorded throughout the study.RESULTS: Group SI had better preservation of lung volumes and capacities in POD compared with Group II (P < 0.05). Pulmonary shunt fraction increased in both groups postoperatively; however, Group SI showed a smaller pulmonary shunt fraction (0.26 +/- 0.04 vs 0.21 +/- 0.04%; P = 0.0014). Functional capacity was significantly reduced in both groups on POD 5; however, Group SI showed better preservation of functional capacity (P = 0.0001). Group SI had better postoperative clinical results, with lower incidence of atelectasis and pleural effusion (P < 0.05), lower pain scores (P < 0.0001), and shorter orotracheal intubation and hospitalization lengths (P < 0.001).CONCLUSIONS: Sub-xyphoid pleural drain determined better functional capacity and exercise tolerance with a smaller pulmonary shunt fraction and improved clinical outcomes compared with intercostal pleural drainage after off-pump coronary artery bypass surgery.Universidade Federal de São Paulo, Cardiol & Cardiovasc Surg Discipline, BR-04023900 São Paulo, BrazilUniversidade Federal de São Paulo, Phys Therapy Sch, Dept Human Mot Sci, BR-04023900 São Paulo, BrazilUniversidade Federal de São Paulo, Cardiopulm Physiotherapy Lab, BR-04023900 São Paulo, BrazilUniversidade Federal de São Paulo, Cardiol & Cardiovasc Surg Discipline, BR-04023900 São Paulo, BrazilUniversidade Federal de São Paulo, Phys Therapy Sch, Dept Human Mot Sci, BR-04023900 São Paulo, BrazilUniversidade Federal de São Paulo, Cardiopulm Physiotherapy Lab, BR-04023900 São Paulo, BrazilWeb of Scienc