Incidence and risk factors for deep venous thrombosis after moderate and severe brain injury.

BACKGROUND

Patients with traumatic injuries possess a high risk of developing deep venous thrombosis (DVT), thus the need for appropriate prophylaxis. Patients with head injuries pose a unique challenge due to contraindication to the use of anticoagulation. We sought to determine the incidence of DVT and identify specific risk factors for its development in patients with head injuries.

METHODS

All head injury admissions between January 1, 2000, and July 31, 2006, with a length of stay >or=7 days were identified. Patient data including age, sex, injuries, Glasgow Coma Scale, Injury Severity Score (ISS), and venous duplex scan results were collected. Mechanical methods were routinely used for prophylaxis; heparin was not used in this population. Weekly duplex screening was commenced at 7 days to 10 days after admission.

RESULTS

There were 939 patients who met criteria for review, however, duplex scans were performed in only 677, which was the population studied. Overall, DVT was present in 31.6%. There were fewer DVTs in patients with isolated head injuries (25.8%) compared with patients with those with head and extracranial injuries (34.3%)--p = 0.026. Independent predictors for DVT identified included male gender (p = 0.04), age >or=55 (p < 0.001), ISS >or=15 (p = 0.014), subarachnoid hemorrhage (p = 0.006), and lower extremity injury (p = 0.001).

CONCLUSIONS

DVT occurs in one third of moderately to severely brain injured patients. Isolated head injuries have a lower incidence. Older age, male gender, higher ISS, and the presence of a lower extremity injury are strong predictors for developing DVT. Regular screening and the use of prophylactic inferior vena cava filters in patients with risk factors should be strongly considered.