The Importance of Being the Morning Case in Adult Cardiac Surgery: A Propensity-Matched Analysis

Objectives: The quality of the outcome after cardiac surgery with cardiopulmonary bypass depends on the patient demographics, co-morbidities, complexity of the surgical procedure, and expertise of surgeons and the whole staff. The purpose of the present study is to analyze the timing of surgery (morning vs afternoon) with respect to morbidity and mortality in adult cardiac surgery. Methods: The primary end-point was the incidence of major morbidity defined according to a modified Society of Thoracic Surgeon criterion. We consecutively included all the adult (> 18 years) patients receiving a cardiac surgery operation at our Institution. Results: From 2017 through 2019 a total of 4,003 cardiac surgery patients were operated. With a propensity-matching technique a final patient population of 1600 patients was selected, with 800 patients in the first-case surgery group and 800 in the second-case surgery group. Patients in the second-case group had a major morbidity rate of 13% vs 8.8% in the first-case group (P = 0.006), and a higher rate of 30-days mortality (4.1% vs 2.3%, P = 0.033). After correction for EuroSCORE and operating surgeon, the second-case group confirmed a higher rate of major morbidity (odds ratio 1.610, 95% confidence interval 1.16-2.23, P = 0.004). Conclusion: Our study suggests that patients operated as second cases are exposed to an increased morbidity and mortality probably due to fatigue, loss of attention and hurriedness in the operating room, and decreased human resources in the intensive care unit.