The Impact of Intra-Abdominal Pressure on Mortality and Morbidity in Patients Undergoing Open-Heart Surgery

Overview

This prospective observational study evaluated whether increased intra-abdominal pressure, meaning increased pressure inside the abdomen, is associated with postoperative complications and mortality in adults undergoing elective open-heart surgery with cardiopulmonary bypass. Intra-abdominal pressure was measured through the urinary bladder at three time points: after anesthesia induction, after closure of the sternum, and two hours after admission to the intensive care unit. Participants with an intra-abdominal pressure of 12 mmHg or higher at any measurement were compared with those whose pressure remained below 12 mmHg. The study examined postoperative recovery outcomes, including time to extubation, length of stay in the intensive care unit and hospital, postoperative complications, and mortality. It also aimed to identify perioperative factors associated with increased intra-abdominal pressure. No study-specific treatment or intervention was assigned, and all patients received standard perioperative care.

This prospective observational cohort study investigated perioperative changes in intra-abdominal pressure in patients undergoing elective open-heart surgery with cardiopulmonary bypass and examined whether increased intra-abdominal pressure was associated with postoperative recovery and adverse clinical outcomes. Intra-abdominal pressure was assessed indirectly through urinary bladder pressure using a standardized measurement technique. Patients were placed in the supine position, 25 mL of sterile saline was instilled into the bladder, and pressure was recorded at end-expiration after zeroing the pressure transducer at the mid-axillary line. Measurements were obtained after induction of anesthesia, after sternal closure, and two hours after admission to the intensive care unit. Intra-abdominal hypertension was defined as an intra-abdominal pressure of 12 mmHg or higher at any measurement time point. Patients meeting this definition were compared with patients whose intra-abdominal pressure remained below 12 mmHg at all measurements. Demographic, clinical, hemodynamic, laboratory, surgical, and postoperative data were collected prospectively. No study-specific treatment or intervention was assigned. Anesthetic management, cardiopulmonary bypass management, fluid therapy, hemodynamic support, and postoperative care were provided according to routine institutional practice. The analyses were designed to evaluate associations between intra-abdominal hypertension and postoperative outcomes and to explore perioperative factors associated with increased intra-abdominal pressure. Because the study was observational, the findings were interpreted as associations rather than evidence of causality