Randomized comparison between a forced air system and warm water bath for resuscitation of neonatal hypothermic calves with or without oral administration of caffeine.

Abstract

BACKGROUND: Hypothermia is a cause of neonatal calf death in cold climates. Practical and effective rewarming methods are important for bovine health within affected regions. HYPOTHESIS/OBJECTIVES: To compare the rewarming rate and blood analytes (glucose, lactate, and cortisol) of calves resuscitated with forced air with warm water bath, with or without oral administration of caffeine. ANIMALS: Twenty healthy neonatal Holstein bull calves. METHODS: In this randomized, prospective study, calves born healthy and without history of dystocia were cooled to 32&#xb0;C rectal temperature then thermally resuscitated using either forced air rewarming or warm water bath (40&#xb0;C) with or without oral administration of caffeine. Rectal temperatures were used to quantify recovery rate. Measurements of glucose, lactate, and cortisol were recorded for every 2&#xb0;C change in rectal temperature. RESULTS: Rectal temperature decline (0.03&#xb0;C per minute) and total cooling time (191.0&#x2009;&#xb1;&#x2009;33.3&#x2009;minutes) did not significantly differ among treatment groups. Calves were successfully resuscitated to 38&#xb0;C by either method. Time required to euthermia using warm water was significantly faster (0.1&#xb0;C per minute; 64.3&#x2009;&#xb1;&#x2009;17.8&#x2009;minute; P&#x2009;<&#x2009;.05) than forced air (0.05&#xb0;C per minute; 123.1 &#xb1;&#x2009;20.0&#x2009;minutes). Caffeine had no significant effect on resuscitation rate (P&#x2009;=&#x2009;.14; 95% CI, -0.002 to 0.024) in either treatment; however, caffeine was associated with reduced time to euthermia by 8.3 and 10.8&#x2009;minutes, respectively. Changes in metabolic variables (glucose, lactate, and cortisol), were inversely related to rectal temperature with no statistical significance among rewarming methods. CONCLUSIONS AND CLINICAL IMPORTANCE: Although warm water submersion is faster, forced air rewarming is an effective alternative for restoration of euthermia.