TREATMENT OF HYPERTHERMIA AND DEHYDRATION WITH HYPERTONIC SALINE IN DEXTRAN

Hyperthermia may be accompanied by dehydration with or without electro lyte loss. To determine the efficacy of hypertonic saline in dextran s olution (HSD, 7.5% NaCl in 6% dextran 70) for the treatment of heat st roke, rats were deprived of water for 24 h (DE) or not (ND), and then they were heat-stressed, and 4 mL/kg of saline (SAL) or HSD was admini stered via jugular cannula at the end of heat stress (a core temperatu re of 42.3 degrees C). The following four groups of 10 rats (Wistar-Fu rth) were used: NDSAL, DESAL, NDHSD, and DEHSD. Four control groups no t subjected to heat stress were also studied. Percent change in plasma volume (PV) from baseline was significantly decreased by DE vs. ND (- 6.8 +/- 1.2 vs. +4.6 +/- 1.6%) and increased by HSD vs. SAL (+10.1 +/- 4.1 vs. -3.5 +/- 1.6%) administration. Rats that were DE had signific antly higher heating rates and less water loss during heat than ND rat s, but hydration status was not correlated to 24 h survival. HSD group s had significantly higher PV and survival rates than their correspond ing SAL groups regardless of hydrational status.