The effects of cardiopulmonary bypass on pulmonary function during robotic cardiac surgery

Factors causing prolonged mechanical ventilation and peri-operative morbidity after robot-assisted coronary artery bypass graft surgery

Robot-assisted coronary artery bypass graft [robot-assisted (coronary artery bypass grafting (CABG)] surgery is the latest treatment for coronary artery disease. However, the surgery extensively affects cardiac and pulmonary function, and the risk factors associated with peri-operative morbidity, including prolong mechanical ventilation (PMV), have not been fully examined. In this retrospective cohort study, a total of 382 patients who underwent robot-assisted internal mammary artery harvesting with mini-thoracotomy direct-vision bypass grafting surgery (MIDCABG) from 2005 to 2012 at our tertiary care hospital were included. The definition of PMV was failure to wean from mechanical ventilation more than 48 h after the surgery. Risk factors for PMV, and peri-operative morbidity and mortality were analyzed with a multivariate logistic regression model. Forty-three patients (11.3%) developed PMV after the surgery, and the peri-operative morbidity and mortality rates were 38 and 2.6%, respectively. The risk factors for PMV were age, left ventricular ejection fraction (LVEF), the duration of one-lung ventilation for MIDCABG (beating time), and peak airway pressure at the end of the surgery. Furthermore, age and anesthesia time were found to be independent risk factors for peri-operative morbidity, whereas age, LVEF, and anesthesia time were the risk factors for peri-operative mortality. These findings may help physicians to properly choose patients for this procedure, and provide more attention to patients with higher risk after surgery to achieve better clinical outcomes.

The effects of hyperoxia liquid regulate cardiopulmonary bypass‑induced myocardial damage through the Nrf2‑ARE signaling pathway

The aim of the present study was to investigate the protective role of hyperoxia liquid in regulating cardiopulmonary bypass (CPB)‑induced myocardial damage and its possible underlying mechanism. In the CPB‑induced rat model, hyperoxia liquid enhanced left ventricular ejection fraction (LVEF), reduced the left ventricular internal dimension systole (LVIDs) level, inhibited malondialdehyde levels, increased superoxide dismutase, glutathione (GSH) and GSH peroxidase levels, suppressed heart cell apoptosis, and induced the nuclear factor erythroid 2‑related factor 2 (Nrf2) and heme oxygenase‑1 (HO‑1) signaling pathway. Then, ML385, a Nrf2 inhibitor, was used to attenuate the effect of hyperoxia liquid on LVEF and LVIDs levels, oxidative stress and heart cell apoptosis in the CPB‑induced rat model. Collectively, the results of the present study demonstrated that the protective role of hyperoxia liquid may regulate oxidative stress in a CPB‑induced rat model through the Nrf2‑antioxidant response element signaling pathway.