Laboratory measures of coagulation among trauma patients on NOAs: results of the AAST-MIT

Leslie M Kobayashi; Alexandra Brito; Galinos Barmparas; Patrick Bosarge; Carlos V Brown; Marko Bukur; Matthew M Carrick; Richard D Catalano; Jan Holly-Nicolas; Kenji Inaba; Stephen Kaminski; Amanda L Klein; Tammy Kopelman; Eric J Ley; Ericca M Martinez; Forrest O Moore; Jason Murry; Raminder Nirula; Douglas Paul; Jacob Quick; Omar Rivera; Martin Schreiber; Raul Coimbra

doi:10.1136/tsaco-2018-000231

Laboratory measures of coagulation among trauma patients on NOAs: results of the AAST-MIT

Trauma Surg Acute Care Open. 2018 Oct 15;3(1):e000231. doi: 10.1136/tsaco-2018-000231. eCollection 2018.

Authors

Leslie M Kobayashi¹, Alexandra Brito², Galinos Barmparas³, Patrick Bosarge⁴, Carlos V Brown⁵, Marko Bukur⁶, Matthew M Carrick⁷, Richard D Catalano⁸, Jan Holly-Nicolas⁹, Kenji Inaba¹⁰, Stephen Kaminski¹¹, Amanda L Klein¹², Tammy Kopelman¹³, Eric J Ley¹⁴, Ericca M Martinez¹⁵, Forrest O Moore¹⁶, Jason Murry¹⁷, Raminder Nirula¹⁸, Douglas Paul¹⁹, Jacob Quick²⁰, Omar Rivera²¹, Martin Schreiber²², Raul Coimbra²³

Affiliations

¹ Division of Trauma, Surgical Critical Care, Burns and Acute Care Surgery, Department of Surgery, University of California San Diego, San Diego, California, USA.
² Department of Surgery, University of California San Diego, San Diego, California, USA.
³ Department of Surgery, Cedars Sinai Medical Center, Los Angeles, California, USA.
⁴ Division of Acute Care Surgery, University of Alabama at Birmingham, Birmingham, Alabama, USA.
⁵ Dell Medical School, University of Texas at Austin, Austin, Texas, USA.
⁶ Division of Trauma, Emergency Surgery, and Surgical Critical Care, Surgical Intensive Care Unit Bellevue Hospital Center, New York, USA.
⁷ University of North Texas Health Science Center, Fort Worth, Texas, USA.
⁸ Loma Linda University Medical Center, Loma Linda, California, USA.
⁹ Department of Surgery, Loma Linda University Medical Center, Loma Linda, California, USA.
¹⁰ Division of Trauma & Critical Care, University of Southern California, Los Angeles, California, USA.
¹¹ Department of General Surgery and Surgical Critical Care, Santa Barbara Cottage Hospital, Santa Barbara, California, USA.
¹² Department of Surgery, Dell Medical School, University of Texas at Austin, Austin, Texas, USA.
¹³ Division of Burns, Trauma, and Surgical Critical Care, University of Arizona Medical School-Phoenix Campus, Phoenix, Arizona, USA.
¹⁴ Department of General Surgery, Cedars Sinai Medical Center, Los Angeles, California, USA.
¹⁵ Chandler Regional Medical Center, Grand Canyon University, Phoenix, Arizona, USA.
¹⁶ Department of General Surgery, Trauma and Surgical Critical Care, Chandler Regional Medical Center, University of Arizona College of Medicine, Chandler, Arizona, USA.
¹⁷ Department of General Surgery Trauma Services, East Texas Medical Center, Tyler, Texas, USA.
¹⁸ Department of General Surgery, University of Utah, Salt Lake City, Utah, USA.
¹⁹ Division of Trauma, Critical Care and Acute Care Surgery, Kettering Medical Center, Kettering, Ohio, USA.
²⁰ Division of Acute Care Surgery, University of Missouri, Columbia, Missouri, USA.
²¹ Division of Trauma and Critical Care, University of Southern California, Los Angeles, California, USA.
²² Division of Trauma, Critical Care & Acute Care Surgery, Oregon Health & Science University, Portland, Oregon, USA.
²³ Department of General Surgery, Riverside University Health System Medical Center, Loma Linda University School of Medicine, Moreno Valley, California, USA.

Abstract

Background: Warfarin is associated with poor outcomes after trauma, an effect correlated with elevations in the international normalized ratio (INR). In contrast, the novel oral anticoagulants (NOAs) have no validated laboratory measure to quantify coagulopathy. We sought to determine if use of NOAs was associated with elevated activated partial thromboplastin time (aPTT) or INR levels among trauma patients or increased clotting times on thromboelastography (TEG).

Methods: This was a post-hoc analysis of a prospective observational study across 16 trauma centers. Patients on dabigatran, rivaroxaban, or apixaban were included. Laboratory data were collected at admission and after reversal. Admission labs were compared between medication groups. Traditional measures of coagulopathy were compared with TEG results using Spearman's rank coefficient for correlation. Labs before and after reversal were also analyzed between medication groups.

Results: 182 patients were enrolled between June 2013 and July 2015: 50 on dabigatran, 123 on rivaroxaban, and 34 apixaban. INR values were mildly elevated among patients on dabigatran (median 1.3, IQR 1.1-1.4) and rivaroxaban (median 1.3, IQR 1.1-1.6) compared with apixaban (median 1.1, IQR 1.0-1.2). Patients on dabigatran had slightly higher than normal aPTT values (median 35, IQR 29.8-46.3), whereas those on rivaroxaban and apixaban did not. Fifty patients had TEG results. The median values for R, alpha, MA and lysis were normal for all groups. Prothrombin time (PT) and aPTT had a high correlation in all groups (dabigatran p=0.0005, rivaroxaban p<0.0001, and apixaban p<0.0001). aPTT correlated with the R value on TEG in patients on dabigatran (p=0.0094) and rivaroxaban (p=0.0028) but not apixaban (p=0.2532). Reversal occurred in 14%, 25%, and 18% of dabigatran, rivaroxaban, and apixaban patients, respectively. Both traditional measures of coagulopathy and TEG remained within normal limits after reversal.

Discussion: Neither traditional measures of coagulation nor TEG were able to detect coagulopathy in patients on NOAs.

Level of evidence: Level IV.

Keywords: anticoagulation; coagulation tests; trauma management.