Effects of MIAVS on Early Postoperative ELWI and Respiratory Mechanics

BACKGROUND: The effects of minimally invasive aortic valve surgery (MIAVS) on the early postoperative extravascular lung water index (ELWI) and respiratory mechanics have rarely been studied. MATERIAL/METHODS: A total of 90 patients were divided into 3 groups: a conventional full sternotomy (CS) group (n=30), an upper ministernotomy (US) group (n=30), and a right anterior thoracotomy (RT) group (n=30). Hemodynamic and respiratory mechanics parameters were recorded at perioperative time points, including before skin incision (T(−1)); at sternum closing (T0); and 4 h (T4), 8 h (T8), 12 h (T12), and 24 h (T24) after the operation. The ventilator support time, ICU length of stay, and postoperative hospitalization time, as well as the thoracic drainage volume and blood transfusion volume, were recorded. RESULTS: The ELWI and pulmonary vascular permeability index (PVPI) increased at T4, and the values were significantly lower in the US group than in the RT group and CS group (P<0.05). At T8, the ELWI and PVPI in the US group and RT group were significantly lower than in the CS group. At T12, there were no significant differences among the 3 groups. In addition, at T4 static lung compliance decreased, plateau airway pressure increased, and airway resistance changed non-significantly. There were no significant differences between the US group and the RT group, but both groups showed better results than the CS group did. CONCLUSIONS: The ELWI and PVPI may transiently increase after aortic valve surgery with cardiopulmonary bypass. Compared with the 12 h required to recover from a conventional sternotomy operation, it may only take 8 h to recover from MIAVS.