Deep venous thrombosis (DVT) and pulmonary embolus (PE) remain common surgical complications, often affecting patients without any prior warning. Postoperative spinal epidural hematomas (SEH) may have a devastating impact on a patient's recovery from a routine procedure. The effect of preoperative DVT prophylaxis administration on elective spinal patients has not previously been studied.
Retrospective cohort analysis.
To correlate the incidence of preoperative DVT prophylaxis administration and the rate of postoperative DVT, PE, and SEH after elective spinal surgery.
Earlier studies have shown a postoperative DVT rate in elective spinal patients of between 0.3% and 31%, a PE rate of 0.2% to 0.9%, and a SEH rate of approximately 0.1%.
About 3870 patient notes, from 2004 to 2008 elective spinal procedures, were reviewed. DVT, PE, and SEH rates were compared between those patients receiving and not receiving preoperative DVT prophylaxis.
The 36.9% of patients received preoperative DVT prophylaxis, and 19 patients suffered and DVT and/or PE. Nine of these had received preoperative prophylaxis, giving an odds ratio of 0.91. Sixteen patients suffered a SEH, and this gave an odds ratio of 1.33. The SEH's presented with a median postoperative time of 4 days.
Preoperative DVT prophylaxis does not influence the rate of postoperative DVT or PE among elective spinal patients. It probably does not influence SEH rate, and it is noted that SEH may present quite late, in contrast to currently accepted time courses.
University of Calgary Spine Program, Foothills Medical Centre, Canada
The authors have not received financial support that requires acknowledgement.
Reprints: Ken C. Thomas, MD, MHSc, FRCSC, University of Calgary Spine Program, Rm AC 144B Special Service Building, Foothills Medical Centre, 1403 29th St NW, Calgary AB T2N 2T9 (e-mail: firstname.lastname@example.org).
Received April 15, 2010
Accepted August 5, 2010