Session: ASME Undergraduate Student Design Expo

Paper Number: 176034

Fluid Flow Analysis of Fresh Whole Blood Transfusion Kit Components 

Tactical Combat Casualty Care (TCCC) Guidelines changed in 2014 to recommend the use of fresh whole blood (FWB) in trauma treatment instead of the previous practice of using component therapy, where blood products are separated and combined before infusion. To facilitate FWB transfusions on the battlefield, military units employ field combat transfusion kits that enable the collection of FWB from a pre-registered donor with a matching blood type and include a means to infuse the collected FWB into the patient. This research explores fluid flow through intravenous (IV) tubing and filter components of FWB transfusion kits used by the military in cold regions, aiming to expand the operating range where servicemembers currently remain untreated.

Fluid delivery for fresh whole blood transfusions is often driven by gravity, achieved by raising the blood bag above the infusion site. The recommended flow rate range is 90-200 mL/min. The two main factors limiting this range are: heat loss through the IV tubing, which causes fluid temperatures to drop below safe transfusion levels, and pressure head loss in the tubing, which can result in insufficient flow rates for emergency fluid delivery. These factors are interconnected; colder fluid temperatures increase viscosity, reducing flow rates and causing the fluid to stay longer in the tubing. Additionally, prolonged cold exposure further lowers fluid temperatures. Previous research quantified heat loss in the transfusion kit and suggested mitigation measures using mathematical models that simulate how insulation material, thickness, and IV tubing length affect fluid delivery temperatures. This current study focuses on quantifying pressure head loss through the transfusion kit with fluid flow analysis and then proposing mitigation strategies for pressure loss. For the filter component in the IV tubing system, a minor loss coefficient is determined experimentally, and the data are used to develop a flow simulation model. Initial pressure head loss analysis shows that, under gravity-driven flow, major head loss accounts for 81.0-96.9% of the total pressure loss, depending on fluid temperature. Initial calculations use water as the working fluid. The goal is to predict fluid flow behavior when blood or blood products are used, through computational modeling and simulation. Mathematical models will also estimate pressure head loss for different IV tubing lengths and diameters, providing information on the minimum required height for the blood bag. The overall aim is to recommend IV tubing length, diameter, and insulation measures based on mathematical models and flow simulations to guide the redesign of field transfusion kits.

Presenting Author: Drew Homan U.S. Military Academy

Presenting Author Biography: Drew Homan is a cadet at the United States Military Academy at West Point and a Mechanical Engineering major from Appleton, Wisconsin. Homan is fascinated by the lifesaving capabilities of medicine and is committed to solving medical problems through the application of mechanics. His undergraduate research focuses on determining why fresh whole blood transfusion kits used by the military fail in cold regions, defining their safe operational limits, and improving the functionality of the kits to expand their usability to save servicemembers’ lives in austere environments. After West Point, Homan plans to develop his technical and leadership abilities by pursuing a graduate degree in Mechanical Engineering and commissioning into the Army Military Intelligence branch before beginning a career in intelligence research and development.

Authors:

Emine Foust U.S. Military Academy
Drew Homan U.S. Military Academy