Hemodynamic effects of chest closure in adult patients undergoing cardiac surgery

Objective: To evaluate hemodynamic effects of sternal retractor removal and sternal closure after cardiopulmonary bypass and to correlate these change s with preoperative and intraoperative variables. Design: Prospective. Setting: University hospital. Participants: Fifty adults undergoing cardiac surgery. Measurements and Main Results: Arterial, pulmonary artery, and transesophag eal echocardiography measurements were obtained immediately before and 1 mi nute after removal of the sternal retractor and immediately before and 1 mi nute after sternal closure. Retractor removal caused a significant decrease in cardiac index by 5.6% (p < 0.01), stroke volume index by 4.0% (p < 0.05 ), and mean pulmonary artery pressure by 4.8% (p < 0.001). Sternal closure caused a significant decrease in cardiac index by 7.7%, stroke volume index by 10.2%, and left ventricular end-diastolic area by 9.2% (p < 0.001) Ther e were significant increases in pulmonary capillary wedge pressure and syst emic vascular resistance by 9.1% and 10.8% (p < 0.01). There was no signifi cant change in the ejection fraction area. The magnitude of decrease in str oke volume index with sternal closure correlated positively with end-diasto lic area immediately before the closure. Conclusion: Chest closure is associated with significant hemodynamic change s and a change in the ventricular transmural pressure-volume relationship. Patients with lower preload immediately before closure are more vulnerable to a decrease in cardiac index. Based on the results of this study, volume appears to be the appropriate preventive and treatment option to limit the impact of chest closure. Copyright (C) 2001 by W.B. Saunders Company.