Introduction: Venous thromboembolism is a common preventable cause of morbidity after surgery with an incidence ranging from 0.3-31% in elective spinal surgery. Therefore, patients undergoing surgery receive routine prophylaxis for DVT. Recently, the added utility of chemical DVT prophylaxis in addition to mechanical DVT prophylaxis has been questioned. We set out to determine comparative effectiveness and cost-benefit of mechanical versus chemical DVT prophylaxis in patients undergoing elective lumbar spinal fusion.
Methods: All patients undergoing lumbar spinal fusion(1-3 levels) for degenerative spine disease over a 2-year period were enrolled into our prospective registry. During the first year, all patients received mechanical and chemical prophylaxis (subcutaneous heparin twice a day) for DVT [chemical prophylaxis group]. During the second year, patients only received mechanical prophylaxis for DVT [mechanical prophylaxis group]. At the end of this 2-year period, we evaluated whether this categorical switch influenced the incidence of DVT and the cost-benefit associated with it.
Results: A total of 355 patients (208 in chemical group and 147 in mechanical group) were included in the study. There were no significant differences in the baseline characteristics and treatment variables of the two groups (p>0.05). The categorical switch from chemical to mechanical DVT prophylaxis did not change the incidence of DVT after lumbar fusion surgery in chemical vs. mechanical prophylaxis group [1 (0.48%) vs. 1 (0.68%); p=0.80] in mechanical prophylaxis group). Incidence of bleeding complications like epidural hematoma was 0.96% in chemical group vs. 0.68% in mechanical group. Converting from chemical to mechanical prophylaxis resulted in $20,937 savings without a rise in peri-operative thromboembolism.
Conclusions: In our experience, mechanical and chemical DVT prophylaxis had equivalent effectiveness in preventing peri-operative DVT after elective lumbar spinal fusion. Use of mechanical versus chemical DVT prophylaxis can lead to cost savings of up to $20,937 per 150 patients treated per year.
Patient Care: Our research shows that mechanical vs. chemical DVT prophylaxis in elective spine surgery have equal effectiveness and use of mechanical DVT prophylaxis can lead to significant cost savings.
Learning Objectives: At the end of the session, participants should be able to: 1) Understand that mechanical vs chemical prophylaxis for DVT has equal effectiveness; 2) Determine that use of mechanical vs. chemical DVT can result in significant cost-savings.