Impact of intraoperative myocardial tissue acidosis on postoperative adverse outcomes and cost of care for patients undergoing prolonged aortic clamping during cardiopulmonary bypass

BackgroundThis study examined the impact of intraoperative myocardial acidosis and adverse postoperative outcomes on the cost of cardiac surgical care.MethodsMyocardial tissue pH corrected to 37°C (pH37C) was measured in 162 patients with cross-clamp (XC) duration of 119 minutes or longer. Perioperative data and outcomes were collected prospectively. The Veterans Affairs cost accounting system was used to determine the cost of care in a subset of 57 patients.ResultsLong XC duration was associated with significantly increased acidosis and adverse postoperative outcomes. The cost of care for patients with adverse outcomes was increased by 110% (P < .0001). Patients with acidosis at the end of reperfusion had significantly (P = .0470) increased costs of care. End reperfusion of myocardial tissue pH37C of less than 7.0, diabetes mellitus, and body surface area were significant determinants of postoperative adverse outcomes.ConclusionsIntraoperative myocardial acidosis is a determinant of postoperative adverse outcomes and cost in cardiac surgery. Reducing XC duration and improving intraoperative myocardial protection should improve outcomes and reduce cost.