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

Status

Completed

Phases

Unknown

Study type

Observational

Source

ClinicalTrials.gov

Registry ID

NCT07752082

Enrollment

100

Registered

2026-08-07

Start date

2023-03-02

Completion date

2024-03-10

Last updated

2026-08-07

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Intra-Abdominal Hypertension, Postoperative Complications

Keywords

Intra-abdominal pressure, intra-abdominal hypertension, morbidity and mortality, cardiopulmonary bypass

Brief summary

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.

Detailed description

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

Interventions

None listed

Study design

Observational model

COHORT

Time perspective

PROSPECTIVE

Eligibility

Sex/Gender

ALL

Age

18 Years to No maximum

Healthy volunteers

Inclusion criteria

* Age 18 years or older * Scheduled for elective open-heart surgery using cardiopulmonary bypass * Left ventricular ejection fraction of 40% or higher * Provision of written informed consent

Exclusion criteria

* Age under 18 years * Requirement for emergency cardiac surgery * Open-heart surgery performed without cardiopulmonary bypass * Body mass index of 35 kg/m² or higher * Uncontrolled diabetes mellitus * History of urinary bladder or urinary tract surgery * Active urinary tract infection * Acute or chronic renal failure * Neurogenic bladder * History or presence of cerebrovascular disease

Design outcomes

Primary

Measure	Time frame	Description
Number of Participants With Postoperative Complications	1 year	The number and percentage of participants who experienced each prespecified postoperative complication were assessed separately. Complications included arrhythmia, surgical-site infection, pneumonia, acute kidney injury, neurological complications, respiratory distress requiring continuous positive airway pressure, postoperative bleeding, reintubation, and prolonged mechanical ventilation. Outcomes were compared between participants with and without intra-abdominal hypertension.
In-Hospital All-Cause Mortality	1 year	The number and percentage of participants who died from any cause during the postoperative hospital stay were assessed and compared between participants with and without intra-abdominal hypertension.

Secondary

Measure	Time frame	Description
Time to Extubation	From completion of surgery to extubation	Postoperative time from completion of surgery to removal of the endotracheal tube, recorded in hours and compared between participants with and without intra-abdominal hypertension.
Intensive Care Unit Length of Stay	4 weeks	Duration of postoperative intensive care unit stay, recorded in hours and compared between participants with and without intra-abdominal hypertension.

Countries

Turkey (Türkiye)

Outcome results