Higher complication rate found with postoperative therapeutic anticoagulation in spine trauma

ORLANDO, Fla. — Results presented here at the American Academy of Orthopaedic Surgeons Annual Meeting showed a 17.5% complication rate among 63 patients with spine trauma when therapeutic anticoagulation was started postoperatively compared to a 6.3% complication rate among a control group of 63 similar patients who did not have anticoagulation therapy started at that time.

“These complications were diagnosed on average on postop day 10,” Brian Shiu, MD, said during his presentation. “The anticoagulation became therapeutic on postop day 12, and the vast majority of patients returned to the OR with 3.5 weeks.”

The patients in the study experienced deep venous thrombosis (29 patients), pulmonary embolism (33 patients) and myocardial infarction (one patient), all of which led to the need for anticoagulation. The initial anticoagulation agent was heparin drips in 50% of patients, weight-based low-molecular-weight heparin (LMWH) in 46% of patients and warfarin in 3.2%, Shiu said.

“After we administered therapeutic anticoagulation, epidural hematoma requiring reoperation for neurological decline occurred in 3% of patients. Both of these patients were initially anticoagulated with heparin drip. Our global reoperation rate was approximately 18% vs. a control group of just 8%. The vast majority of these patients were also anticoagulated initially with heparin drip,” he said.

The most common reasons for reoperation among these patients were bleeding complications and a wound infection.

“Using multivariate analysis we found, interesting enough, that heparin drips compared to LMWH had a significantly higher odds ratio of reoperation and return to the OR,” Shiu said.

“This is the first study to quantify complications secondary to therapeutic doses of anticoagulation,” he said, but noted the study was limited by its definition of anticoagulation.

Patients who were started on heparin drip, but were later switched to Coumadin (Bristol-Myers-Squibb), were only reported as having started on heparin drip.

“We found a trend toward increased complications requiring return to the OR. A higher rate of epidural hematoma was found when fully anticoagulated. A heparin drip may increase the rate of reoperation; however, multicenter studies are needed,” he said. – by Susan M. Rapp

Reference:

Shiu B, et al. Paper #218. Presented at: American Academy of Orthopaedic Surgeons Annual Meeting; March 1-5, 2016; Orlando, Fla.

Disclosure: Shiu reports no relevant financial disclosures.