Incidence of deep vein thrombosis after spinal cord injury: a prospective study in 37 consecutive patients with traumatic or nontraumatic spinal cord injury treated by mechanical prophylaxis.

BACKGROUND: Patients with spinal cord injury (SCI) are at particular risk for deep vein thrombosis (DVT) during their hospital course. In most researches on the prevention of thromboembolic events after SCI, the cause of SCI was usually limited to traumatic origin, and pharmaco-prophylaxis was usually started immediately after SCI irrespective of the presence of DVT. For this reason, it is difficult to determine the exact incidence of DVT after SCI from all possible causes in the absence of anticoagulation treatment. We sought to determine the incidence of DVT and the effect of mechanical treatments without chemical prophylaxis.
METHODS: From November 2009 to October 2010, 37 consecutive patients were admitted to our institute for SCI regardless of causes. Patient data including age, sex, types of injury in motor completeness, causes of SCI, and results of color Doppler ultrasonography (DUS) were collected. Routine mechanical prophylaxis for DVT was performed in all patients; pharmacologic prophylaxis was not used to avoid the potential consequences that may have confounded their benefits. All patients were routinely checked for DVT of lower limbs. Examinations were usually performed within 1 week of injury and repeated fortnightly until any medications for DVT were started in cases of a positive DUS result.
RESULTS: In total, 16 of the 37 (43%) patients with acute SCI routinely given mechanical prophylaxis without anticoagulation were found to have DVT in the lower extremities by color DUS. Ten patients showed new thrombosis by DUS within 7 days after injury, three patients after 2 weeks to 3 weeks, and three patients at more than 1 month after injury. The majority of DVT occurred in the distal leg vein (81.2%, soleal vein). The incidence of DVT in patients with traumatic SCI was not different from that of patients with nontraumatic SCI in this study (p>0.05). Age, sex, type of motor impairment, and cause of SCI were not found to be significantly related to the occurrence of DVT.
CONCLUSIONS: The incidence of DVT in patients with SCI routinely given mechanical prophylaxis without anticoagulation was higher when compared with those reported in the setting of routine pharmaco-prophylaxis. Anticoagulation should not be excluded from initial DVT prophylaxis measures in the SCI patients unless there is any ongoing bleeding or severe coagulopathy. Further studies will be necessary to get a more precise data and to understand the clinical relevance of these results.