Bedside Assessment of Right Ventricular Output Lying in Prone Or Supine

Registry record from ClinicalTrials.gov (NCT07632027). This is a study registration, not published results. Lead sponsor: Sahlgrenska University Hospital. Recruitment status: NOT_YET_RECRUITING. Phase: NA. Study type: INTERVENTIONAL. Enrollment: 70 participants (ESTIMATED). Conditions: Right Ventricular Function, Prone Position, Atelectasis, Atelectases, Postoperative Pulmonary, Cardiac Output, Vasoconstriction, Heart Failure, Recruitment Maneuver, Respiratory Mechanics, Pulmonary Arterial Pressure, Cardiac Surgery, Cardiac Surgery Recovery, Cardiopulmonary Bypass. Interventions: PROCEDURE: Prone position. Primary outcome measures: Cardiac Index , 1 hour after baseline. Brief summary: Right ventricular failure (RVF) is a common complication to cardiac surgery, which is associated to mortality, kidney failure, stroke, prolonged mechanical ventilation and ICU stay. The right ventricle is particularly vulnerable to an increased afterload. By increasing pulmonary vascular resistance (PVR), atelectasis might mitigate a negative effect on the right ventricle. Recruitment maneuvers have been shown to resolve atelectasis and improve hemodynamics by increasing cardiac output and lowering PVR. However these maneuvers transiently raise airway pressures, which in turn increases right ventricular afterload, a situation often poorly tolerated by patients with RVF. Prone position is used in patients with respiratory failure and has been shown to decrease mortality in patients with ARDS. Prone position decreases atelectasis and moves ventilation dorsally. In ARDS it also seems to mediate beneficial hemodynamic effects such as an increase in cardiac output and a decrease in PVR. The investigators hypothesis is that prone position early after cardiac surgery will increase cardiac output by recruitment of atelectasis and thereby decrease PVR.