Paper Number
AB13 

Session
Active and Biological Materials

Title
Effects of sustained low-dosage aspirin consumption on the thixotropic behavior, microstructure and rheology of human blood

Presentation Date and Time
October 12, 2021 (Tuesday) 11:05

Track / Room
Track 4 / Meeting Room C-D

Authors (Click on name to view author profile)

  1. Armstrong, Matthew J. (United States Military Academy, Department of Chemistry and Life Science)
  2. Corrigan, Trevor (United States Military Academy, Chemical Engineering)
  3. Milner, Erin (United States Military Academy)
  4. Bailey, Dorian (United States Military Academy)
  5. Pincot, Andre (United States Military Academy)
  6. Brown, Thomas (United States Military Academy)

Author and Affiliation Lines (in printed abstract book)
Matthew J. Armstrong1, Trevor Corrigan2, Erin Milner3, Dorian Bailey3, Andre Pincot3 and Thomas Brown3
1Department of Chemistry and Life Science, United States Military Academy, West Point, NY 10996; 2Chemical Engineering, United States Military Academy, West Point, NY 10996-1008; 3United States Military Academy, West Point, NY 10996-1008

Speaker / Presenter 
Armstrong, Matthew J.

Keywords
experimental methods; computational methods; applied rheology; biological materials

Text of Abstract
The leading cause of death globally is cardiovascular disease. The cost of this disease as measured by both financial loss and loss of lives has increased dramatically over the last two decades. The scale of this problem necessitates development of as many solutions as practicable. One of the most common preventative measures over the last several decades has been the prophylactic use of sustained, low dosage, acetylsalicylic acid (Aspirin). Even though this approach has been heavily utilized, few if any rheological studies validating the change in physical, mechanical properties of human blood such as viscosity and yield stress at varied shear rates exist in the literature. This is a rheological study of human blood from multiple donors before and after taking a daily 81mg dose of Aspirin for 14 days. The viscosity and yield stress both demonstrate a statistically relevant aggregated decrease across the entire study population. The advancement and evolution of blood modeling to incorporate more thixo-elasto-visco-plastic (TEVP) features to accurately capture transient flow now allows for the use of these models to characterize blood. With recently collected steady state and oscillatory shear flow rheological data from a DHR3 using human we show ‘best-fit’ modeling efforts with the contemporary enhanced thixo-elasto-visco-plastic (TEVP) model. Best fit rheological model parameters are then used to determine values for normal, healthy blood, determine the 95% confidence interval and corroborate correlations with physiological parameters (HDL, LDL, hematocrit, etc.) from literature. Series of physical processes (SPP) analysis is incorporated to illustrate how mechanical properties are tied to the transient, evolving microstructure of human blood and physiological parameters under large amplitude and uni-directional oscillatory shear flow both before and after the 14 day aspirin protocol. LAOS with human blood is then used to build an aggregated mechanical contour map of ‘solid-like’ and 'liquid like' properties.