Effects of lysine-vasopressin treatment on renal function in burned pigs

The effects of lysine vasopressin (LVP) on renal excretory function and renal blood flow were studied in anesthetized and burned pigs either treated conservatively or by early excision 5 hours after burn. Renal perfusion was measured with radioactive microspheres. Diuresis and the urinary excretion of sodium and potassium were determined. Glomerular filtration rate (GFR) was measured either as the endogenous creatinine clearance rate or the clearance rate of 51Cr-EDTA. LVP-treatment in pharmacologic doses after burn caused larger diuresis, and larger sodium and potassium excretion rates than in unburned controls and animals submitted to burn only, Renal blood flow decreased significantly early after burn whether LVP was given or not. After burn, GFR was moderately higher in the LVP-treated pigs than in the animals submitted to burn only. After 24 hours S-creatinine was lower in the pigs treated by LVP and excision of the burned tissues after 5 hours, compared with the conservatively treated animals. This implies that an active surgical approach to full thickness skin burns might support renal function. LVP-induced intrarenal effects causing increased GFR and secondary medullary interstitial electrolyte concentration and osmolar changes could be the mechanisms causing the renal functional changes found in this investigation.