Hemodynamic changes and fluid shifts after large-volume fluid infiltration: results from a porcine model.

While certain parameters such as blood loss and serum lidocaine levels following liposuction have been well studied, fluid shifts between the intravascular and extravascular space have not. With the advent of large volume liposuction, prudent fluid management has become obligatory. Hence, the reason for our study.To test the impact of large volume infiltration on intercompartmental fluid shifts, we measured urine output and hemodynamic changes in 10 anesthetized female Yorkshire pigs weighing between 50 and 85 kg. Eight pigs were infused with 5 to 10 L of tumescent fluid. Two pigs were anesthetized, received no wetting solution, and served as controls. Hemodynamic variables were recorded before infusion and hourly for 48 hours. Animals were extubated after 4 hours of anesthesia. Plasma volume was measured using Evan's Blue Dye, and intravascular fluid shifts were calculated using Foldager's method.Total fluid shift into the intravascular space ranged between 511 and 1036 mL per animal with a mean of 767 mL in the first 3 hours. Higher volumes of fluid infiltration did not lead to fluid overload in the experimental group. Hemodynamic changes were characterized by significant increases in central venous pressure, cardiac output, pulmonary artery pressure, and heart rate consistent with the increase in intravascular volume. Hemodynamic parameters returned to baseline 20 hours following tumescent fluid infiltration.In this porcine model, animals were able to tolerate large fluid challenges delivered by clysis with statistically significant but only modest increases in hemodynamic parameters which gradually returned to baseline within 20 hours.