PB0614 - Use of a Microfluidic Model to Evaluate Platelet Function in Traumatic Brain Injury Patients Pre- and Post- Platelet Transfusion

Monday, June 26, 2023

18:30 – 19:30 ET

Room: Exhibition

Presenting Author(s)

Devin M. Dishong

Research Fellow
Trauma and Transfusion Medicine Research Center, Department of Surgery, University of Pittsburgh
Pittsburgh, Pennsylvania, United States

Co-Author(s)

Emily P. Mihalko, PhD

Research Scientist
Trauma and Transfusion Medicine Research Center, Department of Surgery, University of Pittsburgh
Pittsburgh, Pennsylvania, United States
Amudan J. Srinivasan, MD

Surgical Critical Care Fellow
Trauma and Transfusion Medicine Research Center, Department of Surgery, University of Pittsburgh
Pittsburgh, Pennsylvania, United States
LH

Lara Hoteit, MD

Postdoctoral Research Fellow
Trauma and Transfusion Medicine Research Center, Department of Surgery, University of Pittsburgh
Pittsburgh, Pennsylvania, United States
NA

Nijmeh Alsaadi

Postdoctoral Research Fellow
Trauma and Transfusion Medicine Research Center, Department of Surgery, University of Pittsburgh
Pittsburgh, Pennsylvania, United States
RK

Ronit Kar

Medical Student
University of Pittsburgh - School of Medicine
Pittsburgh, Pennsylvania, United States
DO

David O. Okonkwo

Professor of Neurological Surgery
Department of Neurosurgery, University of Pittsburgh
Pittsburgh, Pennsylvania, United States
JS

Jason L. Sperry

Professor of Surgery
Department of Surgery, University of Pittsburgh
Pittsburgh, Pennsylvania, United States
Matthew D. Neal, MD FACS (he/him/his)

Associate Professor
University of Pittsburgh
Pittsburgh, Pennsylvania, United States
Susan M. Shea, MSME, PhD (she/her/hers)

Assistant Professor
Trauma and Transfusion Medicine Research Center, Department of Surgery and Department of Bioengineering, University of Pittsburgh
Pittsburgh, Pennsylvania, United States

Background: Platelet transfusion is commonly provided to patients with traumatic brain injury (TBI) who are on antiplatelet medication. Microfluidics provide a platform to evaluate platelet function under flow, and may therefore be a valuable tool to assess platelet function in the TBI patient population.

Aims: The study aim was to characterize platelet dysfunction in TBI patients on antiplatelet medication, and measure changes in function after platelet transfusion.

Methods: Pre- and post-transfusion blood samples were obtained from patients diagnosed with TBI who had a history of pre-injury antiplatelet use, and a need for platelet transfusion. Control samples were obtained from healthy volunteers and minimally-injured patients who had neither TBI nor received transfusion. Samples were incubated with anti-CD41 to label platelets, and then perfused through a collagen-coated stenosed microfluidic chamber (initial shear 3500s-1), and real-time immunofluorescent imaging performed. Images were further processed using MATLAB to yield mean fluorescent intensity (MFI), from which fold change and area under the MFI curve (AUC) were derived. Groups were compared using an ANOVA or paired t-test where indicated.

Results: TBI patients on antiplatelet medication had significant platelet dysfunction compared to healthy and minimally-injured controls (Fig.1). Overall, there were no statistical differences between pre- and post-transfusion samples. However, a subset of TBI patients (n=4) with lower low pre-transfusion function exhibited post-transfusion improvement, while another subset that presented with higher pre-transfusion function declined post-transfusion (Fig.2). Analyzing the patients who improved post-transfusion, there was a significant increase post-transfusion function(p=0.04), while there was a modest decrease for patients whose function worsened.

Conclusion(s): Using this novel microfluidic approach to assess platelet function in platelet-transfused TBI patients, we found TBI patients consistently presented with coagulopathy, and exhibited a bimodal response to transfusion resulting in either improvement or increased dysfunction. These data may indicate the need for nuanced, patient-specific protocols for TBI patients on antiplatelet therapy.