Fluid resuscitation is an integral part of critical care for burn injury patients where the necessary infusion rate is determined based on patient’s urinary output (UO). Motivated by an increasing interest in model-based development and in silico testing of automated burn resuscitation algorithms, we are investigating mathematical modeling of hemodynamic responses to burn injury and resuscitation. The model consists of 3 main components: (1) multi-compartmental volume kinetics including vascular and interstitial fluids and the associated flow interactions, (2) burn-induced hemodynamic perturbation including alterations in tissue permeability and compliance as well as denaturation with protein release, and (3) renal regulatory function including glomerular filtration rate as a function of intravascular volume state and reabsorption function representing the UO dependence on vasopressin. Preliminary evaluation of the initial model with data collected from animals show that the model can reproduce general trend of hemodynamic responses anticipated from burn injury and resuscitation.
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Design and In Silico Evaluation of a Closed-Loop Hemorrhage Resuscitation Algorithm With Blood Pressure as Controlled Variable
Abstract This paper concerns the design and rigorous in silico evaluation of a closed-loop hemorrhage resuscitation algorithm with blood pressure (BP) as controlled variable. A lumped-parameter control design model relating volume resuscitation input to blood volume (BV) and BP responses was developed and experimentally validated. Then, three alternative adaptive control algorithms were developed using the control design model: (i) model reference adaptive control (MRAC) with BP feedback, (ii) composite adaptive control (CAC) with BP feedback, and (iii) CAC with BV and BP feedback. To the best of our knowledge, this is the first work to demonstrate model-based control design for hemorrhage resuscitation with readily available BP as feedback. The efficacy of these closed-loop control algorithms was comparatively evaluated as well as compared with an empiric expert knowledge-based algorithm based on 100 realistic virtual patients created using a well-established physiological model of cardiovascular (CV) hemodynamics. The in silico evaluation results suggested that the adaptive control algorithms outperformed the knowledge-based algorithm in terms of both accuracy and robustness in BP set point tracking: the average median performance error (MDPE) and median absolute performance error (MDAPE) were significantly smaller by >99% and >91%, and as well, their interindividual variability was significantly smaller by >88% and >94%. Pending in vivo evaluation, model-based control design may advance the medical autonomy in closed-loop hemorrhage resuscitation.
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- Award ID(s):
- 1760817
- NSF-PAR ID:
- 10353781
- Date Published:
- Journal Name:
- Journal of Dynamic Systems, Measurement, and Control
- Volume:
- 144
- Issue:
- 2
- ISSN:
- 0022-0434
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1115/1.4052312
