Protein C levels can be forecasted by global haemostatic tests in critically ill patients and predict long-term survival.
BACKGROUND
We have shown the usefulness of global haemostatic tests International Normalized Ratio (INR) and Activated Partial Thromboplastin Time (APTT) for predicting survival in critically ill patients. Ability to analyse inhibitors protein C and antithrombin is limited to a small number of laboratories and often only during office hours. We therefore studied the usefulness of global haemostatic tests to predict levels of protein C and antithrombin and investigated value of these latter tests in predicting outcome.


METHODS
Blood samples were collected within 6 h of admission to intensive care unit (ICU) and tested regarding platelet count, INR, and APTT. If platelet count was <100x10(9) L(-1), INR >1.36 and/or APTT >45 s, a second sampling was done within 6 h after the first one for analysis of protein C and antithrombin. Ninety-two patients were included; length of stay at ICU and hospital, survival when leaving ICU and hospital and up to 5 years were recorded.


RESULTS
Using univariate analysis of variance, INR and APTT separately predicted levels of protein C and to some extent antithrombin. Neither platelet count nor any combinations of global haemostatic tests were predictive. Utilising Cox regression, decreased protein C, but not antithrombin, predicted lower survival rate.


CONCLUSIONS
Global haemostatic tests INR and APTT can predict levels of protein C and, though less so, antithrombin. A low protein C level indicated a sinister prognosis in the ICU setting, at the hospital, and after up to 5 years.
Nilsson
Gunnar
G
Department of Anaesthesiology, Lund University, Malmö University Hospital, SE-205 02 Malmö, Sweden. gunnar.a.nilsson@skane.se
Astermark
Jan
J
Lethagen
Stefan
S
Vernersson
Einar
E
Berntorp
Erik
E
D000368:Aged; D000990:Antithrombin III / Q000032:analysis; D002423:Cause of Death; D016638:Critical Illness; D005260:Female; D006801:Humans; D007362:Intensive Care Units; D019934:International Normalized Ratio / Q000401:mortality*; D007902:Length of Stay; D008297:Male; D008875:Middle Aged; D010314:Partial Thromboplastin Time / Q000401:mortality*; D010976:Platelet Count; D011237:Predictive Value of Tests; D011446:Prospective Studies; D011486:Protein C / Q000032:analysis*; D015996:Survival Rate
D011486:Protein C; D000990:Antithrombin III