Identification of hypercoagulability with thrombelastography in patients with hip fracture receiving thromboprophylaxis

Abstract

Background: Venous thromboembolism (VTE) is the second most common complication after hip fracture surgery. We used thrombelastography (TEG), a whole-blood, point-of-care test that can provide an overview of the clotting process, to determine the duration of hypercoagulability after hip fracture surgery. Methods: In this prospective study, consecutive patients aged 51 years or more with hip fractures (trochanteric region or neck) amenable to surgical treatment who presented to the emergency department were eligible for enrolment. Thrombelastography, including calculation of the coagulation index (CI) (combination of 4 TEG parameters for an overall assessment of coagulation) was performed daily from admission until 5 days postoperatively, and at 2 and 6 weeks postoperatively. All patients received 28 days of thromboprophylaxis. We used single-sample t tests to compare mean maximal amplitude (MA) values (a measure of clot strength) to the hypercoagulable threshold of greater than 65 mm, a predictor of in-hospital VTE. Results: Of the 35 patients enrolled, 11 (31%) were hypercoagulable on admission based on an MA value greater than 65 mm, and 29 (83%) were hypercoagulable based on a CI value greater than 3.0; the corresponding values at 6 weeks were 23 (66%) and 34 (97%). All patients had an MA value greater than 65 mm at 2 weeks. Patients demonstrated normal coagulation on admission (mean MA value 62.2 mm [standard deviation (SD) 6.3 mm], p = 0.01) but became significantly hypercoagulable at 2 weeks (mean 71.6 mm [SD 2.6 mm], p < 0.001). There was a trend toward persistent hypercoagulability at 6 weeks (mean MA value 66.2 mm [SD 3.8 mm], p = 0.06). Conclusion: More than 50% of patients remained hypercoagulable 6 weeks after fracture despite thromboprophylaxis. Thrombelastography MA thresholds or a change in MA over time may help predict VTE risk; however, further study is needed.

An in vivo rabbit joint injury model to measure trauma-induced coagulopathy and the effect of timing of administration of ketotifen fumarate on posttraumatic joint contracture

“…Furthermore, decreased mobility secondary to immobilization of the leg may account for the prolonged hypercoagulable state observed. In both hip fracture and total joint replacement patients, there is a similar TEG MA and CI pattern, to what was observed in this model [26–28] . Current thrombosis research in trauma patients does not permit pre-injury TEG analysis.…”

“…In both hip fracture and total joint replacement patients, there is a similar TEG MA and CI pattern, to what was observed in this model. [26][27][28] Current thrombosis research in trauma patients does not permit pre-injury TEG analysis. As trauma induced coagulopathy is an individualized response, our in vivo model allows for a pre-injury baseline TEG measurement.…”

Post hip fracture orthogeriatric care—a Canadian position paper addressing challenges in care and strategies to meet quality indicators

“…Following a hip fracture, patients often experience significant pain, blood loss, and a period of immobilization. This inciting event leads to a hyper-coagulable, catabolic stress state that increases the risk of serious perioperative complications [ 16 – 18 ]. It is thought that timely surgical care shortens the exposure to this harmful state, reducing the risk of perioperative morbidity and mortality.…”

Advances in the Management of Coagulopathy in Trauma: The Role of Viscoelastic Hemostatic Assays across All Phases of Trauma Care

“…Orthopedic surgery patients can remain hypercoagulable for 6 weeks following surgery when assessed with viscoelastic testing despite heparin prophylaxis. 114 Routine heparin prophylaxis in orthopedic surgery demonstrated tranexamic acid (TXA) use in surgery causing hypercoagulability postinjury, although VTE rates were comparable. 115 While heparin does not correct hypercoagulability appreciated by viscoelastic testing, its clinical efficacy is clear, 116 as reducing the frequency of missed heparin doses is one of the few interventions clinicians can directly implement to reduce VTE.…”