Introduction: Ischemia-reperfusion injury during and after resuscitation from cardiac arrest results in increased systemic cell death. Cytokeratin-18 (CK-18) is released into the blood during cell death, its caspase cleaved form (ccCK-18) is specific to apoptosis. This study evaluates their prognostic value for mortality, neurological outcome and their association with conventionally used clinical parameters after successful cardiopulmonary resuscitation (CPR).
Methods: Plasma samples of 40 resuscitated patients were collected 6, 24, and 72 hours after successful CPR to determine the CK-18, ccCK-18 concentrations by ELISA. The circumstances of the cardiac arrest and CPR, laboratory and physical parameters were recorded. Mortality within 30 days was considered end-point.
Results: Resuscitated patients had highly elevated CK-18, ccCK-18 levels and decreased ccCK-18/CK-18 ratio compared to healthy subjects, septic and postoperative patients (CK-18: 3842 vs. 242; 559; 1644 ng/L; ccCK-18/CK-18 ratio: 0.14 vs. 0.58; 0.22; 0.24) [1]. Neither the values of CK-18 and ccCK-18 nor their kinetics showed difference between survivors and non-survivors and they did not show association with the length of the resuscitation, the initial rhythm, the neurological outcome (CPC scale) or the number of the damaged organ systems either. CK-18 showed a declining kinetics in patients with good renal function in contrast to patients with renal failure. Significant negative correlation was observed between the 6-hour CK-18 and hemoglobin concentrations (r=-0.400, p<0.01).
Conclusion: This study was the first to investigate CK-18 and ccCK-18 levels among resuscitated patients. The levels of the investigated biomarkers did not have prognostic value for mortality or neurological outcome in a general resuscitated population. 
Support: „ Supported by the ÚNKP-18-3-I New National Excellence Program of the Ministry of Human Capacities”
References: 1. Stefan Hofer et at. Cell death serum biomarkers are early predictors for survival in severe septic patients with hepatic dysfunction; Critical Care 2009; 13:R93 https://doi.org/10.1186/cc7923

2 - Prognostic value of systemic cell death biomarkers after successful cardiopulmonary resuscitation