Oral Xa Inhibitors versus low molecular weight heparin for thromboprophylaxis after nonoperative spine trauma

Background: Thromboprophylaxis with oral Xa inhibitors (Xa-Inh) are recommended after major orthopedic operation; however, its role in spine trauma is not well-defined. The aim of our study was to assess the impact of Xa-Inh in spinal trauma patients managed nonoperatively. Methods: A 4-y (2013-2016) review of the Trauma Quality Improvement Program database. We included all patients with an isolated spine trauma (Spine-abbreviated injury scale ≥3 and other-abbreviated injury scale <3) who were managed nonoperatively and received thromboprophylaxis with either low molecular weight heparin (LMWH) or Xa-Inh. Patients were divided into two groups based on the thromboprophylactic agent received: Xa-Inh and LMWH and were matched in a 1:2 ratio using propensity score matching for demographics, vitals and injury parameters, and level of spine injury. Outcomes were rates of deep venous thrombosis, pulmonary embolism, and mortality. Results: We analyzed a total of 58,936 patients, of which 1056 patients (LMWH: 704, Xa-Inh: 352) were matched. Matched groups were similar in demographics, vital and injury parameters, length of hospital stay (P = 0.31), or time to thromboprophylaxis (P = 0.79). Patients who received Xa-Inh were less likely to develop a deep venous thrombosis (2.3% versus 5.7%, P < 0.01). There were no differences in the rate of pulmonary embolism (P = 0.73), postprophylaxis packed red blood cells transfusions (P = 0.79), postprophylaxis surgical decompression of spinal column (P = 0.75), and mortality rate (P = 0.77). Conclusions: Oral Xa-Inh seems to be more effective as prophylactic pharmacologic agent for the prevention of deep venous thrombosis in patients with nonoperative spinal trauma compared to LMWH. The two drugs had similar safety profile. Further prospective trials should be performed to change current guidelines.