Association of Intraoperative Haemodynamic and Postoperative Complications in Type A Aortic Dissection Surgery

"After the induction of anaesthesia, a central venous or pulmonary artery catheter was positioned. Based on prior studies, thresholds for central venous pressure were set at 10, 12, 16, and 20 mm Hg. Venous congestion was quantified by time exceeding each CVP threshold and the area under the curve (AUC) surpassing each CVP threshold in mmHg × min. Assessments were limited to pre- and post-CPB periods, as the venous drainage cannulate generated negative CVP during CPB.~An arterial catheter was installed upon room admission. Continuous arterial blood pressure monitoring commenced after exposure to atmospheric pressure and calibration to zero. The MAP was determined using the formula: 2/3 × diastolic blood pressure + 1/3 × systolic blood pressure. Data were logged by automated software every minute. Established thresholds for MAP were 55, 65, and 75 mm Hg. Hypotension was quantified as (1) time under each MAP threshold in minutes and (2) the AUC below each MAP threshold in mmHg × min."