Very Hot Intravenous Fluid in the Treatment of Hypothermia

Warmflo® warming system overheats fluids in simulated clinical conditions

“…Yet in another article by this group, the authors state that "At present, 40°C is believed to be the highest temperature that can be safely administered. There is concern that temperatures greater than 40°C may harm blood cells" [20]. Furthermore, at low-flow rates, blood remains inside the heat exchanger for longer periods, during which significant hemolysis occurs [16].…”

“…Indeed, RBCs exhibit tolerance to a rapid admixing with crystalloid solution heated to 70°C [21]. Infusion of very hot (65°C) and large volumes (80% of blood vol/hr) of IV fluid to beagles was safe with regard to mechanical or thermal injury [20]. Therefore, it cannot be definitely concluded that overheating blood above 42°C is always unsafe.…”

Hyperthermic Resuscitation Is Safe and Effective after Hemorrhagic Shock in Dogs

“…7 In vivo, normotensive euvolemic dogs tolerate 65°C intravenous fluid resuscitation because the blood flow in central veins permits rapid admixture. 8,9 In hemorrhagic shock, the circulating blood volume, and therefore the rate of thermodilution of heated intravenous fluid, is reduced. In a previous study, it was shown that dogs that were bled to a MAP of 65 mm Hg for 1 hour tolerated resuscitation with 51.7°C crystalloid, without significant differences in hemodynamic parameters or serum glutamic-oxaloacetic transaminase and creatinine phosphokinase when compared with 37.8°C resuscitation.…”

“…As described in a previous article, this infusion catheter was designed to minimize the contact time of the infusate with blood. 8 Its unique features include a balloon tip to center the catheter within the vessel to prevent contact with the vessel wall, and a distal tip thermistor for postinfusion temperature monitoring. Ten 25-gauge infusion pots are radially distributed 4 cm proximal to the balloon to promote rapid admixture and dilution of the infusate.…”

“…7 In vivo, a normotensive canine model tolerates 65°C intravenous fluids safely. 8,9 The purpose of our study was to determine whether 65°C fluid can be safely given after hemorrhagic shock, when decreased blood volume lowers the mixing ratio in central vessels.…”