Incidence of reexpansion pulmonary edema in minimally invasive cardiac surgery

Minimally invasive cardiac surgery requires fewer blood transfusions and mediastinitis is less frequently observed compared to conventional median sternotomy surgical intervention, and it leads to earlier recovery and discharge. However, once reexpansion pulmonary edema occurs, the patient requires long-term management in the intensive care unit. This retrospective study was performed to investigate the incidence of reexpansion pulmonary edema in minimally invasive cardiac surgery. Patients who underwent minimally invasive cardiac valve surgery using cardiopulmonary bypass and port-access by a minimal right lateral thoracic incision between January 2010 and January 2018 were enrolled in this single-center retrospective study, which was approved by the institutional review board of Japanese Red Cross Nagoya Daiichi Hospital (Nagoya, Japan), and the requirement for written informed consent was waived. All data were collected from electronic charts. The primary outcome was the incidence rate of reexpansion pulmonary edema in patients undergoing minimally invasive cardiac surgery. A total of 662 patients underwent minimally invasive cardiac surgery, and we analyzed 651 of these cases. No case of reexpansion pulmonary edema was observed in this study. The statistically-calculated incidence rate of reexpansion pulmonary edema was less than 0.6% (95% confidence interval: 0.0-0.6). The incidence of cerebral infarction was 0.92% (n = 6). Intensive care unit stay days, hospital stay days after surgery, and the death rate after 30 days were 1.5 +/- 2.0 days, 9.6 +/- 3.9 days, and 0.15%, respectively. Although there was no incidence of clinical reexpansion pulmonary edema in this study, the predicted incidence of reexpansion pulmonary edema by statistical analysis was less than 0.6%.