A Chemical Heat Pack–Based Method For Consistent Heating of Intravenous Fluids

Abstract

The IVF heating system described here reliably delivered physiologically appropriate temperature intravenous fluids in 2 of the 3 ambient treatment conditions. With the appropriate number of FRH for the ambient conditions, this system enables the delivery of warmed IVF to provide active warming, which may be clinically beneficial in the prevention and treatment of hypothermia.

A Novel Cooling Method and Comparison of Active Rewarming of Mildly Hypothermic Subjects

“…41 Comparisons of rewarming modalities have been traditionally run with mildly hypothermic healthy volunteers, and results are accepted as generalizable to more severe forms of hypothermia. 42,43 LIMITATIONS Intravenous fluids were delivered with neoprene pouch, flow rate, and environmental conditions identical to those tested and described in a prior study, 31 although the liter bag was warmed in circulating water rather than by flameless ration heaters. Because the internal temperature was identical, it is unlikely there was any difference in delivery temperature, although this was not directly measured in our study.…”

“…Intravenous fluids were delivered with neoprene pouch, flow rate, and environmental conditions identical to those tested and described in a prior study, 31 although the liter bag was warmed in circulating water rather than by flameless ration heaters. Because the internal temperature was identical, it is unlikely there was any difference in delivery temperature, although this was not directly measured in our study.…”

“…They were then placed in a 50 × 40 × 0.12 cm (19” × 16” × 0.5”) neoprene pocket cut to enable folding into a 30 × 15 × 5 cm (12” × 6” × 2”) rectangle with overlapping sides. 31 The warmed IVF were then suspended 150 cm above the angiocatheter tip and infused through uninsulated 280 cm standard IV tubing (Primary Symbiq Set, Hospira, Inc, Lake Forest, IL). All IVF was run “wide open,” which was measured with a graduated cylinder and a stopwatch as approximately 77 mL/min (≈ 1 L/13 minutes).…”

“…Research has shown that infusion of IVF warmed to 46.3±1.7°C and administered in this manner under the same environmental conditions delivered IV fluids at a temperature of 39.7±0.7°C. 31…”

A simple improvised prehospital method to warm intravenous fluid

“…A study examining the impact of infusing warmed (32°C) versus control (23.2°C) fluid during air‐ambulance transport found that patients who received warm fluid had a higher core temperature (36.8°C vs 35.5°C) on arrival to the emergency department 6 . The unavailability of devices designed for heating intravenous fluid in the field has led some EMS personnel to improvise methods using available resources 7 …”