Warmed IV Fluids to Neonates

Abstract

Objective Neonatal hypothermia is one of the major contributors to both neonatal morbidity and mortality. Being prone to rapid heat loss, low-birth-weight neonates are at highest risk. Providing intravenous (IV) fluids that are not above hypothermic temperatures may lead to inadvertent cooling of neonates, resulting in an increased chance of hypothermia. While there are many interventions that have been studied to provide improved thermal care to low birth weight neonates, none have looked at warming IV fluids or have been done in the setting of critical care transport. This study looks at the most effective means to provide warmed IV fluids to low-birth-weight neonates during critical care out-of-hospital transport. Methods Three methods of providing warmed IV fluids were studied: no warming method (control) (n=14), applying the enFlowTM IV fluid and blood warmer to the IV tubing (n=14), and applying the Belmont® buddy liteTM IV fluid and blood warmer to the IV tubing (n=14). The end of the IV tubing was elevated five inches to simulate typical venous back pressure. The fluid was released at a rate of 10 mL/hr, a common rate used for low-birth-weight neonates. The temperature of the IV fluid as it exited the tubing was measured using a temperature data logger every 10 seconds for 42 minutes. This timeframe was chosen to simulate the average out-of-hospital transport time. We compared the average temperature of the IV fluid, the temperature of the IV fluid at the end of each trial, and the percentage of time that the temperature was above 36.3°C, which is considered the baseline temperature for neonatal hypothermia, across the three methods to measure warming effectiveness. Results Both the enFlow and the Belmont buddy lite IV fluid and blood warmers yielded a greater average temperature of IV fluid (p<0.0001 for both), greater temperature of IV fluid at the end of each trial (p<0.0001 for both), and greater percentage of time above 36.3°C (p<0.0001 for both) than no warming method. The enFlow warmer yielded a greater percentage of time above 36.3°C (p=0.0136) than the Belmont buddy lite warmer. The 95% confidence intervals of the enFlow for the average temperature of the IV fluid and the temperature at the end of each trial were 37.51°C to 38.80°C and 37.69°C to 39.07°C, respectively, with both intervals being above 36.3°C. The 95% confidence intervals of the Belmont buddy lite for the average temperature of the IV fluid and the temperature at the end of each trial were 37.77°C to 39.07°C and 38.07°C to 39.65°C, respectively, with both intervals also being above 36.3°C. Conclusions Both the enFlow and Belmont buddy lite IV fluid and blood warmers were effective in providing warmed IV fluids throughout out-of-hospital transport. The enFlow warmer was more consistent at providing warmed IV fluid than the Belmont buddy lite warmer. These findings may be influential towards modifying protocols to include using a warmer, particularly an enFlow warmer, to prevent neonatal hypothermia. Neonatal hypothermia is one of the major contributors to both neonatal morbidity and mortality. Being prone to rapid heat loss, low-birth-weight neonates are at highest risk. Providing intravenous (IV) fluids that are not above hypothermic temperatures may lead to inadvertent cooling of neonates, resulting in an increased chance of hypothermia. While there are many interventions that have been studied to provide improved thermal care to low birth weight neonates, none have looked at warming IV fluids or have been done in the setting of critical care transport. This study looks at the most effective means to provide warmed IV fluids to low-birth-weight neonates during critical care out-of-hospital transport. Three methods of providing warmed IV fluids were studied: no warming method (control) (n=14), applying the enFlowTM IV fluid and blood warmer to the IV tubing (n=14), and applying the Belmont® buddy liteTM IV fluid and blood warmer to the IV tubing (n=14). The end of the IV tubing was elevated five inches to simulate typical venous back pressure. The fluid was released at a rate of 10 mL/hr, a common rate used for low-birth-weight neonates. The temperature of the IV fluid as it exited the tubing was measured using a temperature data logger every 10 seconds for 42 minutes. This timeframe was chosen to simulate the average out-of-hospital transport time. We compared the average temperature of the IV fluid, the temperature of the IV fluid at the end of each trial, and the percentage of time that the temperature was above 36.3°C, which is considered the baseline temperature for neonatal hypothermia, across the three methods to measure warming effectiveness. Both the enFlow and the Belmont buddy lite IV fluid and blood warmers yielded a greater average temperature of IV fluid (p<0.0001 for both), greater temperature of IV fluid at the end of each trial (p<0.0001 for both), and greater percentage of time above 36.3°C (p<0.0001 for both) than no warming method. The enFlow warmer yielded a greater percentage of time above 36.3°C (p=0.0136) than the Belmont buddy lite warmer. The 95% confidence intervals of the enFlow for the average temperature of the IV fluid and the temperature at the end of each trial were 37.51°C to 38.80°C and 37.69°C to 39.07°C, respectively, with both intervals being above 36.3°C. The 95% confidence intervals of the Belmont buddy lite for the average temperature of the IV fluid and the temperature at the end of each trial were 37.77°C to 39.07°C and 38.07°C to 39.65°C, respectively, with both intervals also being above 36.3°C. Both the enFlow and Belmont buddy lite IV fluid and blood warmers were effective in providing warmed IV fluids throughout out-of-hospital transport. The enFlow warmer was more consistent at providing warmed IV fluid than the Belmont buddy lite warmer. These findings may be influential towards modifying protocols to include using a warmer, particularly an enFlow warmer, to prevent neonatal hypothermia.