D 2 O Equilibration Rates in Thermally Injured Animals. ∗

Abstract

Summary

1. The average time to equilibrium following intravenous injection of D₂O in 16 normal adult mongrel dogs was 129.4 minutes. Equilibrium was established in thermally injured dog in 148.1 minutes. There were no statistically significant differences between animals before and after thermal injury. 2. Equilibrium should not be assumed to be complete at 2 hours in either normal or pathologic states. Consecutive blood samples should be taken over a longer period of time, preferably up to 5 hours. A point of equilibrium should be selected when variation is within 5% of final volume of distribution at 5 hours. 3. Because of wide variation in time to equilibrium in both normal and pathologic states, any conclusions regarding changes in “efficiency of total circulation” should be studied carefully and interpreted cautiously.