Intra-abdominal hypertension in critically ill patients after emergency abdominal surgery: incidence, risk factors, and patient outcome

Background and Objectives: Intra-abdominal hypertension (IAH) is frequently encountered in patients undergoing major emergency abdominal surgery and is associated with adverse outcomes in the intensive care unit (ICU). This study aims to evaluate the prevalence, risk factors, and outcomes of IAH in a surgical ICU setting. Methodology: This prospective observational study was conducted at the Center for Anesthesia & Surgical Intensive Care, Bach Mai Hospital, from April 2023 to September 2023. We included adult patients who underwent emergency major abdominal surgery and were in the surgical ICU for more than 48 h. Intra-abdominal pressure (IAP) was measured via a urinary bladder catheter upon ICU admission, and subsequently at 24 and 48 h. IAH was classified according to the World Society of the Abdominal Compartment Syndrome guidelines from 2013. The incidence of IAH and treatment outcomes, including the number of days on mechanical ventilation and the 28-day mortality rate, were recorded. Odds ratios (OR) and 95% CI were calculated to assess the effect size of perioperative risk factors. Results: Among 92 patients, 38 were diagnosed with IAH. The majority of these patients had IAH grade I, (31.5%), with no cases of grade IV observed. multivariable Logistic-regression analysis revealed several risk factors for IAH included septic shock (odds ratio [OR]; 95% confidence interval [CI]: 3.31; 1.34-8.01), peritoneal fluid (5.28; 1.33-21.05), massive fluid resuscitation (6.93; 1.38-34.80), intra-abdominal infection (7.19; 2.58-20.04), and coagulopathy (3.73; 1.55-8.94). Patients with IAH had a significantly longer duration of mechanical ventilation and ICU length of stay (P = 0.009 and P = 0.049, respectively). The 28-day mortality rate was markedly higher in the IAH group compared to the non-IAH group (34% vs. 5.6%, P = 0.000). A strong correlation was observed between IAH and 28-day mortality, with each 1 mmHg increase in IAP associated with a 5.3-fold increase in mortality rate. Conclusion: IAH is common among patients undergoing major emergency abdominal surgery and is linked to prolonged ICU stay, extended mechanical ventilation, and increased 28-day mortality. Key risk factors for IAH include septic shock, intra-peritoneal fluid collections, massive fluid resuscitation, intra-abdominal infection, and coagulopathy.