Venous Thromboembolism After Spine Surgery.

STUDY DESIGN

Retrospective cohort study.

OBJECTIVE

To measure the rate of postoperative venous thromboembolic events (VTE) after spine decompression and fusion procedures.

SUMMARY OF BACKGROUND DATA

VTE after spine surgery is a serious complication, but chemoprophylaxis is not without significant risk due to the concern of epidural hematoma. Current literature report widely variable rates of VTE, and have weaknesses in sample size, specificity of diagnosis, and methodological problems with adequate patient follow-up.

METHODS

State-level inpatient, ambulatory surgery, and emergency department administrative databases were used to track patients for clinically significant VTE within 90 days of discharge after a spine procedure.

RESULTS

Of 357,926 patients enrolled, one-third underwent spine decompression alone, whereas two-thirds received a spine fusion. The overall rate of VTE was 1.37% (95% CI: 1.33-1.41), but varied widely depending on diagnosis, 1.03% for structural degenerative diagnoses to 10.7% for spine infection. Posterior cervical fusion had a higher rate of VTE than anterior cervical fusion, whereas anterior thoracolumbar and lumbosacral fusions had higher rates than the respective posterior approaches. Additional risk factors included patients receiving long spine fusions and having multiple procedures during the hospitalization. Forty percent of VTEs discovered after discharge were diagnosed at a different hospital.

CONCLUSION

The rate of spine VTE varies widely depending on diagnosis and procedure. It is important to risk-stratify patients who present for spine surgery to identify patients at increased risk who should be monitored for the development of VTE. It is important to know that nearly half of VTEs that occur after discharge are diagnosed at different hospitals, and thus the primary surgeon may be initially unaware of the complication. These results from a large selection of historical patients may provide a tool for estimating patient risk depending on diagnosis and type of procedure.

LEVEL OF EVIDENCE