Coagulopathy as a parameter to predict the outcome in head injury patients--analysis of 61 cases

The correlation of coagulopathy and pupillary light reflex, the degree of midline shift in brain computer tomography and Glasgow outcome scale (GOS) after head injury were prospectively evaluated. From September 2002 to March 2003, 61 patients (45 males and 16 females; mean age: 41.9 years) after head injury were enrolled in the study. A modified coagulopathy score (CS) defined by prothrombin time, partial thromboplastin time, platelet count, D-dimer and fibrinogen was calculated for each patient within 24 h after injury. The CS was 2.3+/-2.7 (mean+/-SD). The incidence of abnormal coagulation following head injury in non-survival cases was 100% and in survival cases 66%. The mortality rate was significantly increased to 75% in CS above 4 and 100% if CS was 6 or greater. The increase of D-dimer concentration appears to be common yet abnormal platelet counts are relatively uncommon among head trauma patients. Within 4 h after head injury, there is an initial hypercoagulable stage followed by hypocoagulable stage 6 h after head injury. Our results showed pupillary light reflex has the most significant correlation to GOS (rho = 0.727, p < 0.0001). It also reveals that coagulopathy score > or 4 (positive predictive value 90%) may have higher degree of accuracy to predict mortality comparing to both pupils being fixed or brain CT midline shift > or = 15 mm. We conclude that: (1) Coagulation state in head injury patients within 24 h after injury is of value in determining the outcome. (2) Coagulopathy score > or = 4 is a good predictor to evaluate mortality rate of head injury patients.