Prevalence and prognostic relevance of abnormal liver function tests in critically ill patients with cardiac arrest

Patients with out-of-hospital cardiac arrest and in-hospital cardiac arrest have a poor prognosis. Laboratory biomarkers that are frequently altered in critically ill patients with cardiac arrest are liver function tests. However, the predictive value of abnormal liver function tests in the cardiac arrest setting remains unclear.

Four hundred seven patients who were treated after cardiac arrest in an intensive care unit at a tertiary-care hospital were included in the analysis. To classify LFT abnormalities, we used established upper limit of normal values and multiples thereof according to the NIH Common Terminology Criteria for Adverse Events (CTCAE). Kaplan-Meier estimates and cox proportional hazard models combined with the CardShock risk score were performed to investigate the association between liver function abnormalities and patient outcomes.

Thirty-nine different combinations of elevated liver function tests have been observed in the study cohort. The most common abnormalities included an increase in aspartate aminotransferase (AST) levels, followed by an increase in alanine aminotransferase (ALT) and gamma-glutamyl transferase (GGT) levels. Kaplan-Meier estimates showed significant differences in 90-day survival rates depending on severity of AST, ALT, bilirubin, and INR elevations. A cox proportional hazard model analysis demonstrated that a combined increase in bilirubin and INR together with the CardShock risk score allowed the highest mortality prediction.

Abnormal liver function tests can be frequently observed after cardiac arrest, with different patterns of damage having different prognostic relevance. The combination of elevated bilirubin and INR offers important prognostic information regarding 90-day mortality, particularly when added to validated risk tools, and can be used to identify patients at risk.