PEEP Therapy for Patients With Pleurotomy During Coronary Artery Bypass Grafting

Abstract

Severe pulmonary oxygenation impairment resulting from peripheral lung atelectasis occurred in some patients with pleurotomy during the harvest of the internal mammary artery graft followed by coronary artery bypass grafting (CABG). We studied the efficacy of intraoperative positive end-expiratory airway pressure (PEEP) therapy for the prevention of postoperative pulmonary oxygenation impairment. A total of 66 patients with solitary CABG procedure were included in this study. The pleural cavity was intraoperatively opened in 44 patients and not opened in 22. PEEP therapy was not used in any patient before May 1996 (referred to herein as the former period) and was used more recently in eight patients with pleurotopmy (referred to herein as the latter period). PEEP was initiated immediately after pleurotomy during the harvest of the internal mammary artery graft. Without PEEP therapy, values of PaO2, A-aDO2, and respiratory index (RI) were worse in patients with pleurotomy than in those without pleurotomy. Meanwhile, there were no major differences in these values between patients with or without pleurotomy after the induction of PEEP therapy. Respiratory insufficiency (A-aDO2 > 400 mmHg and RI > 1.5) was detected in six patients with pleurotomy in the former period. Three of these six patients required over 1 week of long-term mechanical respiratory support. No respiratory insufficiency occurred in patients of the latter period. In conclusion, PEEP therapy, which is initiated just after pleurotomy, may prevent oxygen impairment and pulmonary atelectasis after extracorporeal circulation (ECC) and is recommended for patients with pleurotomy, especially for patients with preoperative low respiratory function.

Continuous positive airway pressure does not improve lung function after cardiac surgery

“…5 Ishikawa also reported that positive endexpiratory pressure (PEEP) with a pressure of 5 cm H 2 O initiated immediately after pleurotomy, prevents oxygen impairment and atelectasis after extracorporeal circulation. 12 However, the duration of the positive effects of PEEP was not documented in that study.…”

“…The technique was reported as an effective treatment in some studies, 5,12,13 however others reported either no difference, or a short-lived difference between patients who received CPAP and those who did not. 4,14,15 In addition, there is no consensus regarding the optimal level of CPAP.…”

Early open-lung ventilation improves clinical outcomes in patients with left cardiac dysfunction undergoing off-pump coronary artery bypass: A randomized controlled trial

“…This mechanism may explain other findings, in particular, the group of patients with better pulmonary function preservation also presented with better oxygenation and lower pulmonary shunt fractions. Previous evidence suggests that PEEP could improve oxygenation during the early postoperative phase of cardiac surgery [14-18] . We hypothesize that this improvement in gas exchange could be associated with the reexpansion maneuvers (for pulmonary opening) associated with PEEP, which maintained the alveoli open.…”

CPAP at 10 cm H2O during cardiopulmonary bypass does not improve postoperative gas exchange

“…Ishikawa et al [15] have reported that CPAP at 5 cmH 2 O applied just after pleurotomy prevents the deterioration of pulmonary gas exchange indexes and decreases atelectasis formation after CPB in patients submitted to cardiac surgery. However, the authors have also observed that these effects could no longer be sustained during post-operative recovery.…”