Risk factors for spinal epidural hematoma after spinal surgery.

STUDY DESIGN: A case-control retrospective analysis comparing patients who developed a postoperative spinal epidural hematoma with patients who did not develop this complication.

OBJECTIVES: To identify risk factors for the development of an epidural hematoma following spinal surgery.

SUMMARY OF BACKGROUND DATA: Neurologic deterioration following spinal surgery is a rare but devastating complication. Epidural hematomas should be suspected in the patient who demonstrates a new postoperative neurologic deficit. The risk factors that predispose a patient to a postoperative spinal epidural hematoma have not been identified.

METHODS: Patients who underwent spinal surgery at a single institution over a 10-year period were retrospectively reviewed. Twelve patients who demonstrated neurologic deterioration after surgery and required surgical decompression because of an epidural hematoma were identified. All cases involved lumber laminectomies. A total of 404 consecutive patients that underwent lumbar decompression and did not develop an epidural hematoma formed the control group. Factors postulated to increase the risk of postoperative spinal epidural hematoma were compared between the two groups using logistic regression.

RESULTS: Multilevel procedures (P = 0.037) and the presence of a preoperative coagulopathy (P < 0.001) were significant risk factors. Age, body mass index, perioperative durotomies, and postoperative drains were not statistically significant risk factors.

CONCLUSIONS: Patients who require multilevel lumbar procedures and/or have a preoperative coagulopathy are at a significantly higher risk for developing a postoperative epidural hematoma.