Pulmonary Embolism Following Major Spinal Deformity Corrective Surgery in Adults

OBJECTIVE: To determine the incidence of pulmonary embolism and contributing factors following major spinal deformity corrective surgery in adults.

INTRODUCTION: Although pulmonary emboli are known to occur following spinal surgery, there are limited published data on the incidence of PE and its contributing factors following major spinal deformity corrective surgery. Incidence of PE in this patient population has been reported to be as high as 3-17%. We report our experience in 417 patients.

MATERIAL AND METHODS: From 1992-99, 417 patients (F 347, M 70) aged 20-87 (avg. 51) underwent spinal deformity corrective surgery (146 primary, 271 revision). Surgical approaches include 23 anterior, 155 posterior, 167 same-day combined, and 72 staged combined. All surgeries were performed by the senior author (JPK). Average intra-operative blood loss was 3100. Comorbiditiy risk was assessed by ASA score (1 – 28, 2 – 233, 3 – 143, 4 – 3; avg. 2.3). Fusion levels varied as follows: <5 – 108; 5-10 – 192; >10 – 107. Prophylaxis included TEDS/SCDS, coumadin, heparin, and low molecular weight heparin. We retrospectively reviewed the patients who suffered pulmonary emboli on our service and identified possible contributory factors.

RESULTS: The incidence of PE was 2.6% (11/417; M 2, F 9; aged 26-64, avg. 50). Diagnosis by spiral CT or V/Q scan occurred on average on post-op day 4.4 (range 1-13). Two had prior histories of PE/DVT. Eighty percent were diagnosed on or before post-op day 4. Average INR (2.8) and PTT (3) were elevated at time of diagnosis. Average intra-operative blood loss was 2700cc (1000-5000). Average number of levels was 8.6 (4-14). Of the 11, 5 were anterior approaches, 5 were posterior alone, and 4 were combined; 7 were revisions. ASA scores averaged 2.6 (range 2 – 3). Of the 11, 3 died (27%).

CONCLUSION: The incidence of PE following major spinal corrective surgery in adults is significant. Sex, age, blood loss, and revision status were not factors affecting mortality. The majority of PEs was diagnosed early and occurred despite therapeutic lab values. The high incidence of mortality in this patient population makes it imperative to further investigate PE in this patient population.