Use of Nuclear Magnetic Resonance Spectroscopy to Assess Renal Dysfunction After Hypertonic-Hyperoncotic Resuscitation in Rats

Abstract

The aim of this study was to evaluate the renal tolerance of a hypertonic-hyperoncotic solution (HHS) administration during uncontrolled hemorrhagic shock (UHS). UHS was produced in rats by a preliminary bleed followed by tail amputation. Hydroxyethylstarch (HHS) 200/0.5 6% in NaCl 7.2% was administered to the HHS groups (n = 20) and normal saline (NS) to the NS group (n = 20). Infusion rates were adjusted to prevent mean arterial pressure (MAP) from falling either below 40 mm Hg in the HHS40 (n = 10) and NS40 groups (n = 10), or below 80 mm Hg in the HHS80 (n = 10) and NS80 groups (n = 10). Data obtained were compared with a sham group and a no resuscitation (NR) group. Nephrotoxicity was evaluated by nuclear magnetic resonance analysis in urine samples. Survival was 60% in the NS40 group and 40% in the NS80 group, 70% in the HHS40 group, and 60% in the HHS80 group (p = not significant). Within and between target groups of 40 mm Hg MAP and 80 mm Hg MAP, there was no significant difference in survival. The mean values of renal metabolites to creatinine (ct) ratios were not significantly different among the six groups. Principal component analysis showed that the HHS80 group was characterized by an increase in allantoin/ct and urea/ct ratios demonstrating acute renal dysfunction and failure of nitrogen metabolism. In prolonged UHS, an infusion of HHS may not increase the rate of survival. HHS infusion in normotensive resuscitation appears to be associated with renal toxicity.