Supplementary Material for: Abdominal hypoperfusion and acute kidney injury in the critically ill patient with liver cirrhosis– a prospective cohort study.

Background Reduced abdominal perfusion pressure (APP) is an underdiagnosed potential pathophysiological mechanism for acute kidney injury (AKI) in the patient with liver cirrhosis and ascites. This study aimed to analyze the prevalence of abdominal hypoperfusion (AhP) (APP <60 mmHg) and the impact of APP on AKI in critically ill patients with liver cirrhosis. Methods This was a post-hoc analysis from a prospective cohort study set in a general ICU at a tertiary university hospital. Patients were recruited between October 2016 and December 2021. Acute renal failure (ARF) was defined by AKI stage 3 following the International Club of Ascites. Results Fifty-eight patients where included, with a mean age of 57(±8.4) years, 79.3% were male, and 93.1% had acute-on-chronic liver failure at admission. The prevalence of AhP was 75.3% and 29.3% of cases had persisting AhP during the first week of ICU stay. Patients with baseline AhP had a higher 28-day mortality compared to those without AhP (respectively, 76.0% vs. 48.5%, p=0.03). Acute renal failure developed in 48.3% of patients. Higher serum urea (aOR 1.01, IC95% 1.001-1.02, p=0.04) and white blood cell count (WBC) (aOR 1.1, IC95% 1.01-1.2, p=0.02) at ICU admission, as well as low persisting APP (aOR 0.9, IC95% 0.86-0.98, p=0.02) were independent risk factors for ARF. Conclusion Critically ill patients with liver cirrhosis presented a high prevalence of ARF, independently associated with higher baseline serum urea and WBC, and lower persisting APP. A structured clinical approach to optimize APP may reduce renal dysfunction in high-risk patients with cirrhosis.