Jonathan N. Grauer, Jeremy L. Fogelson.
Response/Recommendation: Venous Thromboembolism (VTE) chemoprophylaxis can probably be started within 24 – 48 hours following elective lumbar fusions, and within 48 hours following patients considered to be higher risk with bleeding. Chemoprophylaxis benefits should be carefully weighed against the risks of bleeding and hematoma formation.
Strength of Recommendation: Limited.
Rationale: VTE is a significant adverse event after spine surgery that might be minimized with the use of appropriate prophylaxis regimen. However, the use of prophylaxis needs to be balanced by the risks associated with any intervention, such as bleeding, wound issues, etc. In spine surgery, there is particular concern about the possibility of hematoma which could cause compression of the spinal cord/nerves, and the potential of neurologic sequelae.
The risk/benefit considerations of using VTE prophylaxis are dependent on understanding the incidence of this adverse outcome, as well as the associated risks; unfortunately, both of these factors are reported with variable numbers in the literature. Other subgroups are evaluating which specific agents for VTE chemoprophylaxis that should be considered following spine surgery, what screening is recommended, and if there are surgical/procedural/presentation variables that should influence the decision. This sub-group is asked to evaluate the literature regarding when VTE chemoprophylaxis can be started following spine procedures if it is to be used.
Evaluation of the literature: If pursued, VTE chemoprophylaxis is most relevant during the time of greatest risk. An evaluation of the National Surgical Quality Improvement Program (NSQIP) database revealed that deep venous thrombosis (DVT) was diagnosed a median of 10.5 days after anterior cervical surgery and 8 days after posterior lumbar surgery1. The first days were not high incidence, but there could be a delay from onset to detection, so it is difficult to know what to conclude from this information.
A recent survey study of 370 neurosurgeons highlighted the variation in thoughts on the posed question regarding safe timing of chemoprophylaxis following spine surgery2. For uncomplicated elective spine surgery, most respondents are comfortable starting chemical prophylaxis on postoperative day 1 (59.1%), followed by day 2 (23.5%) and day 3 (9.4%), with a range of 0 – 14 days (mean 1.6 days). Those who were more senior in their careers recommended later start of chemoprophylaxis.
Another survey study of 193 orthopaedic and neurosurgical spine surgeons asked similar questions for timing of starting chemoprophylaxis after high-risk spinal surgery3. The most common response was 48 hours after surgery (21 of 94, 22%). However, individual responses varied widely: 12% chose less than 24 hours, 15% chose 24 hours, 13% chose 72 hours, and 10% chose 96 hours. Some indicated they would start chemoprophylaxis before surgery, whereas others responded they would never use it. The most common basis for this decision was noted to be personal experience.
In terms of retrospective reviews, one group evaluated patients who underwent elective one- or two-stage lumbar spinal fusions at a high-volume single institution4. This group found the odds of developing a VTE within 30 days was reduced in those who received chemoprophylaxis within 24 hours of surgery (odds ratio = 0.189, p = 0.025) with no difference in bleeding rates. In a trauma population, one study suggested starting chemoprophylaxis within 48 hours of surgery5.
Another retrospective, single-institution study found higher prevalence of 30-day VTE in those who received chemoprophylaxis 1 day before to 3 days after surgery to be higher than the non-chemoprophylaxis group (presumably related to differential in populations who were not randomized) but no difference in the rates of epidural hematoma6. Other studies have also found no increase in epidural hematoma with chemoprophylaxis6,7, but at least one found the rate of epidural hematoma to be increased8. Unfortunately, these studies did not specifically assess the variable of when the chemoprophylaxis was started.
Conclusions: There are probably different risk/benefit considerations for chemoprophylaxis based on the risk inherent to patient sub-populations of patients undergoing spine surgery. This becomes a balance of minimizing VTE and avoiding epidural hematoma. No prospective study is identified to help answer this question. Retrospective studies seem to suggest that VTE chemoprophylaxis can be started within 24 or 48 hours. Survey studies were mixed by many respondents suggested postop day one, based on experience.
In the absence of more defined data, the current evidence/opinions are interpreted to suggest stating VTE chemoprophylaxis postoperative day one after spine surgery. However, this needs to be assessed based on individual situations and balanced by mixed suggestions of at least some evidence of increased risk of epidural hematoma.
1. Bohl DD, Webb ML, Lukasiewicz AM, et al. Timing of Complications After Spinal Fusion Surgery. Spine (Phila Pa 1976). 2015;40(19):1527-1535. doi:10.1097/BRS.0000000000001073
2. Adeeb N, Hattab T, Savardekar A, et al. Venous Thromboembolism Prophylaxis in Elective Neurosurgery: A Survey of Board-Certified Neurosurgeons in the United States and Updated Literature Review. World Neurosurg. 2021;150:e631-e638. doi:10.1016/j.wneu.2021.03.072
3. Glotzbecker MP, Bono CM, Harris MB, Brick G, Heary RF, Wood KB. Surgeon practices regarding postoperative thromboembolic prophylaxis after high-risk spinal surgery. Spine (Phila Pa 1976). 2008;33(26):2915-2921. doi:10.1097/BRS.0b013e318190702a
4. Kiguchi MM, Schobel H, TenEyck E, et al. The risks and benefits of early venous thromboembolism prophylaxis after elective spinal surgery: A single-centre experience. J Perioper Pract. Published online July 23, 2021:17504589211002070. doi:10.1177/17504589211002070
5. Zeeshan M, Khan M, O’Keeffe T, et al. Optimal timing of initiation of thromboprophylaxis in spine trauma managed operatively: A nationwide propensity-matched analysis of trauma quality improvement program. J Trauma Acute Care Surg. 2018;85(2):387-392. doi:10.1097/TA.0000000000001916
6. Dhillon ES, Khanna R, Cloney M, et al. Timing and risks of chemoprophylaxis after spinal surgery: a single-center experience with 6869 consecutive patients. J Neurosurg Spine. 2017;27(6):681-693. doi:10.3171/2017.3.SPINE161076
7. Cox JB, Weaver KJ, Neal DW, Jacob RP, Hoh DJ. Decreased incidence of venous thromboembolism after spine surgery with early multimodal prophylaxis: Clinical article. J Neurosurg Spine. 2014;21(4):677-684. doi:10.3171/2014.6.SPINE13447
8. McLynn RP, Diaz-Collado PJ, Ottesen TD, et al. Risk factors and pharmacologic prophylaxis for venous thromboembolism in elective spine surgery. Spine J. 2018;18(6):970-978. doi:10.1016/j.spinee.2017.10.013