Effect of prewarmed crystalloid fluids and an in-line fluid warming device on fluid outflow temperatures at ambient temperatures of 21-22°C and 3.5°C.

Equine veterinarians frequently treat patients in non-climate-controlled (i.e., hospitalized) settings. In colder environments, intravenous (IV) fluid administration can contribute to patient hypothermia. The objective of this study was to evaluate three IV fluid warming mechanisms to determine their effect on fluid outflow temperatures at ambient temperatures of 21-22°C and 3.5°C. In this study, fluid outflow temperatures were measured using three warming mechanisms: (1) pre-warmed fluids at 42°C, (2) an in-line warming device placed 163 cm away from the Luer-lock fluid line adaptor (location 1) on the fluid line, and (3) an in-line warming device placed 88 cm away from the Luer-lock fluid line adaptor (location 2) on the fluid line. These warming mechanisms were compared to outflow temperatures measured using no warming mechanism at ambient temperatures of 21-22°C and 3.5°C with flow rates of ∼12 L/hour (gravity flow bolus) and 999 mL/hour. All outflow temperatures were measured with a thermistor. At ∼12L/hour, the use of pre-warmed fluids increased outflow temperatures at both ambient temperatures of 21-22°C and 3.5°C ambient temperatures and an in-line warming device placed at location 1 significantly increased outflow temperatures in 3.5°C ambient temperatures. At 999 mL/hour, use of pre-warmed fluids or an in-line warming device, placed at either location, increased outflow temperatures at ambient temperatures of 21°C or 3.5°C.