Objective: To determine the incidence, diagnostic features, and perioperative predictors of acute cholecystitis after cardiovascular surgery.
Design: Inception cohort study.
Setting: A tertiary care 54-bed cardiothoracic ICU.
Patients: All patients admitted to an ICU after cardiovascular surgery during a 42-month period.
Intervention: Collection of relevant preoperative, operative, and ICU data from a database and medical charts.
Primary outcome: Postoperative acute cholecystitis (AC).
Results: Out of 11,330 admissions, 876 patients stayed in the ICU more than 7 days and 30 of them (3%) developed postoperative AC. AC was diagnosed a median of 26 days after cardiovascular surgery (interquartile range, 11 to 41 days). All patients with AC developed at least two criteria of the systemic inflammatory response syndrome (SIRS), and 16 of them (53%) were vasopressor-dependent on the day of diagnosis. Trends in biochemical testing of liver function were not diagnostic for AC. Death occurred in seven of 17 patients (41%) who underwent cholecystectomy, three of nine patients (33%) treated with percutaneous cholecystostomy, and one of four patients (25%) treated conservatively (p=not significant). Specific earlier predictors of AC were arterial vascular disease, preoperative oxygen delivery less than 430 mL/min · m2, longer times on cardiopulmonary bypass, surgical re-exploration, ICU course complicated by cardiac arrhythmia, mechanical ventilation ≥3 days, bacteremia, and nosocomial infections.
Conclusion: The incidence of AC is low after cardiovascular surgery. Although SIRS and hemodynamic instability were common at the time of diagnosis, the delayed occurrence and lack of specificity of these features for AC limited their utility for early diagnosis. Specific predictors of AC should be sought in the ICU setting to identify patients who are at risk for AC after cardiovascular surgery. When identified, such predictors can prompt earlier diagnosis and treatment. Further evaluation of the selection criteria for different treatment options is needed in order to decrease the morbidity and mortality associated with AC.