Serial Studies of Protein C in Trauma Patients

To investigate the serial changes of protein C after trauma, protein C activity and protein C antigen concentration were measured on the day of the injury and on the 1st, 3rd, and 5th days after admission. Seventy-six trauma patients after mild, moderate, and severe injury (Injury Severity Score of≤10, 11 to 24, and≥25, respectively) were the participants. The incidence of disseminated intravascular coagulation (DIC), multiple organ dysfunction syndrome (MODS) and the mortality rate were differed between the groups. On the day of the injury the moderate- and severe-injured patients had shown markedly low levels of protein C activity and protein C antigen concentration, but the levels had gradually increased to the normal range on the 5th day after the admission. When the patients were complicated with DIC, the protein C activity and the protein C antigen concentration showed significantly lower values than those for non-DIC patients. Further, the DIC patients were classified into subgroups of survivors and nonsurvivors. The protein C activity and the protein C antigen concentration decreased significantly in the nonsur-vivors compared with those in the survivors and the levels remained low throughout the studying period. In conclusion, protein C activity and protein C antigen concentration decrease after trauma, and the DIC enhances those decrease. Low levels of protein C in severely injured patients with DIC may have some role posttrauma MODS.