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Published on: September 30, 2021
The utility of thromboelastography for guiding recombinant activated factor VII therapy for refractory hemorrhage
Marcin Wasowicz1, Massimiliano Meineri, Stuart M McCluskey
1Department of Anesthesia, Toronto General Hospital, Toronto, Ontario, Canada. marcin.wasowicz@uhn.on.ca
Objective:
Recombinant activated factor VII (rFVIIa) is being increasingly used in cardiac surgical patients with refractory hemorrhage. In this study, the authors assessed the ability of thromboelastography (TEG) in guiding rFVIIa therapy in this setting.
Design:
Retrospective study.
Setting:
Tertiary care university hospital.
Participants:
Thirty-eight consecutive patients who received rFVIIa for refractory hemorrhage after cardiac surgery and had a complete coagulation profile including TEG within 30 minutes before and after rFVIIa.
Interventions:
Standard coagulation (prothrombin time, partial thromboplastin time, platelet number, and fibrinogen) and TEG measurements (r time, k time, alpha angle, and maximum amplitude) before and after rFVIIa therapy were compared between responders and nonresponders (determined retrospectively based on clinical records).
Measurements And Results:
Twenty-eight patients (74%) were classified as responders. There were no consistent changes in standard coagulation and TEG measurements before and after rFVIIa therapy. The number of abnormalities in pretreatment coagulation tests was related to response rates; odds of response were 11-fold (95% confidence interval [CI]) and 33-fold (95% CI) greater among patients with 0 or 1 abnormality in standard coagulation tests and TEG measures, respectively, than those with 2 or more abnormalities.
Conclusions:
TEG may be a useful tool for predicting response to rFVIIa in the setting of refractory hemorrhage after cardiac surgery.
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