Respiratory dysfunction after coronary artery bypass grafting employing bilateral internal mammary arteries: the influence of intact pleura

Objective: To evaluate the role of intact pleurae regarding the postoperati ve respiratory functional status in patients undergoing coronary revascular ization employing both internal mammary arteries (IMAs), according to the p edunculated or skeletonized technique (SKT) with opened or. intact pleurae. Materials and methods: Using both IMAs, 299 patients underwent elective co ronary revascularization. They were randomized and divided into group I (n = 82, undergoing IMA harvesting according to the SKT without opening the pl eurae); group TI (n = 186, undergoing IMA harvesting according the peduncul ated technique with open pleurae); and group III (n = 31, undergoing IMA ha rvesting according the SKT with incidentally opened pleurae). There were no differences regarding the preoperative patient characteristics and the ana esthetic and surgical management. Results: There were two deaths in group I versus seven in group II and one in group III (P = ns). The number of tota l areterial myocardial revascularization and arterial composite grafts was significantly higher in groups I and III than in group Il, (P < 0.001 and P < 0.005, respectively). The incidence of postoperative complications was s imilar between groups. Blood loss of >1000 ml was significantly higher in g roup H than group I (P < 0.028); but the incidence of re-thoracotomy and bl ood transfusion was similar between groups. The mechanical ventilation time was significantly higher in groups II and III versus group I (P < 0.018 an d P < 0.02, respectively), The incidence of prolonged ventilation (>24 h), pleural effusion, thoracocentesis and atelectasis, resulted in being signif icantly higher in group II than group I. The incidence of thoracocentesis w as significantly higher in group III than group I. The pain score and analg esic requirements at 1-12 h after awakening were significantly higher in gr oups IT and III versus group I, becoming similar after the chest tubes were removed. PaO2 was significantly higher, and PaCO2 and FiO(2) were signific antly lower in group I than groups TI and III at 1 and 4 h before extubatio n and at I and 4 h after extubation. PaO2 and PaCO2 became similar between groups at the 5th postoperative day. Conclusions: According to our results, we may conclude that pleural integrity has beneficial effects on the respi ratory functional status after coronary revascularization using both IMAs. A meticulous and more careful IMA harvesting approach significantly reduces the postoperative morbidity regarding the pulmonary functional status, and as a consequence, reduces the hospital costs. (C) 2001 Elsevier Science B. V. All rights reserved.