INFLUENCE OF FLUID RESUSCITATION ON RENAL-FUNCTION IN BACTEREMIC AND ENDOTOXEMIC RATS

Purpose: Fluid resuscitation, which is the most important primary ther apy in sepsis, is not always able to prevent acute renal failure. In t his study, we investigated in two different rat models of distributive shock whether fluid resuscitation would increase renal plasma flow (R PF) and subsequently glomerular filtration rate (GFR). Materials and M ethods: In pentobarbital anesthetized Wistar rats Haemaccel (Behring P harma, Hoechst, the Netherlands) infusion (1.2 mL/100 g/h for 3 hours) was started immediately during either bacteremia (bolus of living Esc herichia coli bacteria, 10(9) or endotoxemia (1 hour infusion of E. co li endotoxin, 8 mg/kg), as well as in time-matched healthy controls. R esults: After 3 hours, this treatment had increased RPF (clearance of I-131-hippurate) above normal in control (+67%) and bacteremic rats (75%), whereas in endotoxemic animals, the significantly decreased RPF was normalized. On the other hand, in bacteremic animals, the lowered GFR (clearance of creatinine; x44%) was normalized, whereas in endotox emic animals GFR remained depressed (x30%). The lack of improvement in GFR during endotoxemia was also indicated by a profound fall in urine flow, which by contrast steadily increased in control and bacteremic rats owing to volume loading. In both shocked groups, the decreased re nal oxygen delivery was normalized, but the higher renal oxygen consum ption than expected on the basis of the work needed for sodium reabsor ption was not influenced by Haemaccel treatment, despite the fact that it caused this work load to rise in bacteremic but not in endotoxemic rats. In both shock models, renal cortical adenosine triphosphate con tent did not differ from healthy controls and was not influenced by vo lume loading. Conclusions: In conclusion, our study suggests that a de crease in GFR caused by live bacteria in the circulation may benefit f rom fluid resuscitation, while during endotoxemia this therapy could n ot prevent acute renal failure. Copyright (C) 1997 by W.B. Saunders Co mpany.