An Automated Hardware-in-Loop Testbed for Evaluating Hemorrhagic Shock Resuscitation Controllers

Area of Science:

• Biomedical Engineering
• Critical Care Medicine
• Physiological Modeling

Background:

• Hemorrhage is a major cause of mortality, necessitating effective fluid resuscitation strategies.
• Closed-loop resuscitation systems offer potential but require resource-intensive development and evaluation.
• Comparing infusion controllers across diverse physiological conditions remains a significant challenge.

Purpose of the Study:

• To introduce a novel hardware-in-loop automated testbed for resuscitation controllers (HATRC).
• To provide a robust and accessible methodology for evaluating closed-loop resuscitation systems.
• To facilitate the comparison of infusion controllers under various physiologically relevant hemorrhage scenarios.

Main Methods:

• Development of HATRC, a flow-loop benchtop system utilizing PhysioVessels to simulate pressure-volume dynamics.
• Integration of subject variability, infusate switching, and adjustable fluidic resistance to mimic vasopressor effects.
• Computer-controlled outflow rates simulating hemorrhage, clotting, and urine production.
• Evaluation of a decision-table controller using HATRC across different sampling rates and hemorrhage scenarios.

Main Results:

• HATRC enables quantification of twelve performance metrics for controller evaluation.
• Testing revealed heterogeneous controller performance across different hemorrhage scenarios, underscoring the need for comprehensive evaluation.
• The system demonstrated its capability to modulate physiological parameters like arterial resistance.

Conclusions:

• HATRC provides a user-friendly platform for evaluating closed-loop resuscitation controllers.
• The testbed facilitates the assessment of controller performance under user-defined hemorrhage conditions.
• Utilizing HATRC for extensive controller troubleshooting can expedite product development and clinical translation.