Outcomes and Predictors of Abdominal Compartment Syndrome in Acute Pancreatitis: Insight from the US National Inpatient Sample Database

Introduction: Abdominal compartment syndrome (ACS) is caused by intra-abdominal hypertension, which can result in multiple organ dysfunction syndrome and, potentially, death. Increasing attention has been paid to ACS in patients with acute pancreatitis (AP). This study investigates the clinical outcomes of ACS in patients with AP. Methods: Using the National Inpatient Sample 2017-2020, we employed the International Classification of Diseases, Tenth Revision, Clinical Modifications (ICD-10- CM) codes to identify adult patients (aged ≥18 years) admitted with a principal diagnosis of AP. We further classified AP hospitalizations based on the presence or absence of ACS. Using a multivariate regression model, we compared the outcomes between the 2 arms and determined the predictors of ACS. STATA 14.2 was utilized for statistical analysis. Results: We included 219,835 hospitalizations for AP, of which only 218 (0.001%) were complicated by ACS. After adjusting for confounding variables, we found significantly higher odds of mortality (adjusted odds ratio [aOR] 88.87, P< 0.01), septic shock (aOR 79.83, P< 0.01), acute kidney injury requiring dialysis (aOR 90.63, P< 0.01), acute respiratory failure (aOR 88.74, P< 0.01), mechanical ventilation (aOR 310.35, P< 0.01), disseminated intravascular coagulation (aOR 4.35, P< 0.01), portal venous thrombosis (aOR 4.35, P< 0.01), and peritonitis (aOR 14.57, P< 0.01) in AP patients with ACS (Table 1). In addition, patients in the ACS arm had higher odds of requiring invasive procedures, such as pancreatic drainage and necrosectomy (aOR 8.03 & 21.22, respectively, P< 0.01). Furthermore, using multivariate logistic regression analysis, we determined the predictors of ACS in patients with AP. Obesity (aOR 2.01, P< 0.01), blood transfusion (aOR 21.08, P< 0.01), and admission to large-sized (aOR 1.81, P= 0.01) and teaching hospitals (aOR 1.62, P= 0.04) were identified as positive predictors of ACS, whereas age (aOR 0.98, P< 0.01), female sex (aOR 0.31, P< 0.01), smoking (aOR 0.42, P< 0.01), biliary etiology of AP (aOR = 0.31, P< 0.01), and uninsured patients (aOR 0.39, P= 0.01) were negative predictors. Conclusion: Our study found significantly worse outcomes in patients with AP with ACS and identified predictors of ACS in patients with AP. These findings underscore the importance of early recognition and prompt management of ACS in patients with AP to improve outcomes and reduce the healthcare burden. Table 1. - Unadjusted and adjusted outcomes of acute pancreatitis hospitalizations complicated by abdominal compartment syndrome Acute pancreatitis +Age >=18: (n=219,835) Outcomes With abdominal compartment syndrome (n=218) Without abdominal compartment syndrome (n=219,617) *Adjusted OR (95% CI) P-value Mortality, % 30.28 0.56 88.87 (56.73 - 139.28) < 0.01 Septic shock, % 34.86 0.44 79.83 (51.83 - 122.97) < 0.01 TPN, % 14.22 0.91 11.95 (6.86 - 20.83) < 0.01 ARDS, % 16.06 0.15 88.74 (51.46 - 153.05) < 0.01 Mechanical ventilation, % 83.03 1.28 310.35 (177.89 - 541.45) < 0.01 Requiring ICU admission, % 84.40 1.36 364.86 (202.19 - 658.38) < 0.01 AKI, % 88.99 11.92 87.49 (42.99 - 178.06) < 0.01 AKI requiring dialysis, % 27.52 0.33 90.63 (56.81 - 144.58) < 0.01 DIC, % 7.34 1.04 4.35 (2.04 - 9.27) < 0.01 Portal venous thrombosis, % 7.34 1.04 4.35 (2.04 - 9.27) < 0.01 Peritonitis, % 5.96 0.21 14.57 (6.37 - 33.33) < 0.01 Paralytic ileus, % 3.67 0.22 16.16 (7.03 - 37.17) < 0.01 Requirement of pancreatic drainage, % 7.80 0.72 8.03 (4.07 - 15.84) < 0.01 Pancreatic necrosectomy, % 16.06 0.60 21.22 (11.93 - 37.76) < 0.01 Decompressive laparotomy, % 1.38 0.00 289.41 (47.44 -1765.67) < 0.01 Adjusted Mean Difference Mean Length of hospital stay, days (95% CI) 24.65 (21.09 - 28.21) 4.22 (4.19 - 4.24) 18.01 (13.58 - 22.45) < 0.01 Total Hospitalization Charges, mean, USD 467,450 (396,745 -538,154) 41,260 (40,761 -41,760) 436,938 (338,168 -535,707) < 0.01 *Adjusted for sex, age, hospital bed size, Charlson index, hospital location, hospital teaching status, insurance status, race, smoking, ESRD, alcohol abuse, diabetes mellitus, obesity, and cirrhosis. CI means confidence interval.TPN, Total parenteral nutrition; ARDS, Acute respiratory distress syndrome; ICU, intensive care unit; AKI, Acute kidney injury; DIC, Disseminated intravascular coagulation; ESRD, End-stage renal disease; GERD, Gastroesophageal reflux disease.