A Mathematical Model for the Study of Hemorrhagic Shock and Fluid Resuscitation: Exchange of Fluid and Solutes between Vascular, Interstitial, and Tissue Cell Compartments
Abstract
The transfer of fluid from extravascular compartments into the vasculature is an important recovery mechanism for hemorrhage. This paper describes a three-compartment model (i.e., vascular. interstitial, and tissue cell) that predicts intra-extravascular fluid exchange following hemorrhage and fluid resuscitation. This three-compartment model assumes that capillary pressure is a linear function of blood volume, that interstitial pressure is a nonlinear function of extravascular volume. and that lymph flow is a function of interstitial pressure. Starting with this simple three-compartment model, the effects of model assumptions on plasma volume predictions were assessed. By varying model assumptions and comparing plasma volume predictions, we determined that separate tissue cell and interstitial compartments were required for predicting the plasma volume response to infusions of resuscitative solutions containing small, permeable solutes (e.g., NaCl). We also determined that the interstitial space could be described by a constant hydrostatic pressure, that considerations of interstitial exclusion volumes were not required, and that lymph flow could be considered constant. Plasma volume predictions generated by the three-compartment model were also compared to observed plasma volumes for validation. Model, Hemorrhage, Fluid resuscitation, Transcapillary exchange, Body fluid shifts.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jun 01, 1993
- Accession Number
- ADA266426
Entities
People
- Tammy J. Doherty
Organizations
- Letterman Army Hospital