Roger Ramcharan, MD, PhD
Surgical Critical Care Fellow
St. Joseph Mercy Ann Arbor, United States
Disclosure information not submitted.
Megan Shulkosky, PharmD (she/her/hers)
Pharmacy Resident
Cleveland Clinic
Cleveland, Ohio
Disclosure information not submitted.
Wendy Wahl, MD, FACS, FCCM,FCCM
Surgical ICU Director, Surgical Critical Care Fellowship Director
The Ohio State Wexner Medical Center, United States
Disclosure information not submitted.
Jason Hecht, BCCCP, BCPS, PharmD
Clinical Pharmacy Specialist - Surgical Critical Care
St. Joseph Mercy Ann Arbor
Ann Arbor, MI
Disclosure information not submitted.
Title: The Effect of Antiplatelet Agents on Thromboelastography
Introduction: Thomboelastography (TEG) is a point of care viscoelastic test that can quickly provide an assessment of clot formation and kinetics. Providers utilize this information in real time to make clinical decisions, such as resuscitating a hemorrhaging patient. Antiplatelet agents are commonly prescribed in our patient population, but there is limited literature evaluating the effect they have on clot kinetics outside of platelet inhibition. We aimed to evaluate the relationship between antiplatelet agents and other clot kinetics as defined by TEG.
Methods: We conducted a retrospective study of adult patients at St. Joseph Mercy Ann Arbor who underwent TEG from February 1, 2018 to December 31, 2020. Patients who received anticoagulants within 72 hours or a blood transfusion within 24 hours were excluded. Demographic, clinical, and laboratory data were reviewed. We evaluated the effect of antiplatelet agents on TEG clot kinetics with a subgroup analysis evaluating aspirin monotherapy versus dual antiplatelet therapy.
Results: Within our database of 1060 patients, 50 were controls and 69 were on antiplatelet agents (37 aspirin monotherapy, 27 dual antiplatelet therapy). Between the control and antiplatelet therapy groups, there was no significant difference in clot time (5 seconds versus 4.84 seconds, p=0.499), maximal clot strength (60.8 degrees versus 60.8 degrees, p=1), or fibrinogen levels (408.1 mg/dL versus 426.9 mg/dL, p=0.356). As expected, patients in the antiplatelet group had a significantly higher percent platelet inhibition compared to the control group (45.3% versus 11.1%, p< 0.001). When compared to control patients, patients on dual antiplatelets had increased maximal clot strength (60.8 degrees versus 63 degrees, p=0.0478) and fibrinogen levels (408.1 mg/dL versus 481.5 mg/dL, p=0.0015). When compared to patients on aspirin alone, patients on dual antiplatelets again had increased maximal clot strength (58.8 degrees versus 63 degrees, p=0.0102) and fibrinogen levels (384.1 mg/dL versus 481.5 mg/dL, p=0.0043).
Conclusions: Compared to control patients and those on aspirin alone, patients on dual antiplatelets have increased maximal clot strength and increased fibrinogen levels. These results can help physicians better target product resuscitation in patients who are on antiplatelet agents.