After achieving euvolemia on an anesthetized cannulated adult pig, infuse warm Plasma-Lyte crystalloid solution at a rate of 100 milliliters per minute. Confirm the recording of hemodynamic endpoints, such as heart rate, fraction of oxygen saturated hemoglobin, respiratory rate, end-tidal carbon dioxide, CVP, SBP, DBP, MAP, pulse pressure variability or PPV, SPAP, DPAP, and MPAP. Next, measure cardiac output or CO and PCWP after every 500 milliliters of Plasma-Lyte administration until a 15%CO decrease from the previous measurement exists.
After total volume administration, perform an arterial blood gas analysis to obtain the partial arterial oxygen pressure, pH, lactate, and base excess of the pig. In the adult pig model, heart rate and MAP displayed a linear relationship during forced hypervolemia, but did not demonstrate statistical significance. In comparison, the CVP, CO, and PCWP showed both linearity and statistical significance.
Moreover, the PPV demonstrated a moderate inverse correlation and statistical significance. MAP showed statistical significance, but with an inverse relationship to volume, suggesting volume administration decreased MAP in piglets. No other hemodynamic variable, such as heart rate or PPV demonstrated a linear regression to volume administration or any statistically significant relationship.
