Alveolar Recruitment Strategy During Cardiopulmonary Bypass Does Not Improve Postoperative Gas Exchange and Lung Function

Abstract

Pulmonary dysfunction with impairment of lung function and oxygenation is one of the most serious problems in the early postoperative period after cardiac surgery. In this study we investigated the effect of alveolar recruitment strategy during cardiopulmonary bypass on postoperative gas exchange and lung function. This prospective randomized study included 32 patients undergoing elective myocardial revascularization with cardiopulmonary bypass. In 16 patients 5 cm H(2)O of positive end-expiratory pressure was applied after intubation and maintained until extubation (Group I). In the other 16 patients (group II) a positive end expiratory pressure (PEEP) of 5 cm H(2)O was maintained as well but was increased to 14 cm H(2)O every 20 min for 2 min during cross clamp. Measurements were taken preoperatively, before skin incision, before and after (3, 24, 48 h) cardiopulmonary bypass and before discharge (6th postoperative day). Postoperative gas exchange, extravascular lung water and lung function showed no significant difference between the groups. Postoperative pulmonary function variables were lower in both groups compared to baseline values. In patients with normal preoperative pulmonary function, application of an alveolar recruitment strategy during cardiopulmonary bypass does not improve postoperative gas exchange and lung function after cardiac surgery.

Perioperative lung protective ventilation

“…For example, studies in multiple settings have been unable to show that temporary gains in either lung mechanics or oxygenation extend to the postoperative environment, even when the recruitment maneuver is performed shortly before extubation 7079808182. However, the benefits of recruitment maneuvers may be enhanced or prolonged by the performance of repeated maneuvers 83.…”

Preventing and managing perioperative pulmonary complications following cardiac surgery

“…A randomized clinical trial [27] found no beneficial effects of these maneuvers during coronary artery bypass grafting (CABG), although other studies in the cardiac surgery setting reported that these maneuvers improved the respiratory function in the perioperative period, reducing atelectasis and improving the gas exchange [28][29][30]. It is mainly indicated in cases of hypoxemia due to alveolar collapse, as observed in anesthetized patients.…”

Alveolar recruitment: who needs? how? when?

“…Ficou evidente que a repetição das manobras de recrutamento alveolar, além de aprimorar a troca gasosa e mecânica respiratória, mantém seus efeitos benéficos no período pós-operatório. 52,[57][58][59][60][61][62][63][64][65][66][67] Cirurgia cardíaca e torácica O desenvolvimento de atelectasias constitui a complicação mais comum no pós-operatório de cirurgia cardíaca e torácica, 8,43 sendo aproximadamente seis vezes maior do que o observado em cirurgias abdominais. 68 As alterações pulmonares associadas a esses procedimentos possuem fisiopatologia multifatorial e são resultado da combinação de diversos fatores.…”