Retrospective comparison of caffeine and doxapram for the treatment of hypercapnia in foals with hypoxic-ischemic encephalopathy.

ABSTRACT

BACKGROUND: Despite a lack of data regarding their efficacy, both caffeine and doxapram have been recommended for treatment of hypercapnia in equine neonates with central nervous system damage. HYPOTHESIS: Caffeine and doxapram alleviate hypercapnia in foals with hypoxic-ischemic encephalopathy. ANIMALS Sixteen foals treated with either caffeine (n = 8) or doxapram (n = 8). METHODS: Information on age, body temperature, heart rate, respiratory rate, arterial blood gas parameters, duration of therapy, and outcome was abstracted from each medical record. RESULTS: Therapy with doxapram resulted in a significant decrease in partial pressure of carbon dioxide (PaCO2 [P= .004]), bicarbonate concentration (P= .002), and base excess (P= .005) compared with baseline values but failed to correct acidemia. In contrast, administration of caffeine did not result in significant changes from baseline values. The percentage decrease in PaCO2 and bicarbonate concentration was significantly greater in foals treated with doxapram than in foals treated with caffeine (P= .004). The proportions of foals that achieved the targeted PaCO2 (< or = 50 mmHg) were significantly higher in foals treated with doxapram than in foals treated with caffeine (P= .029). The proportion of survivors in the 2 treatment groups was not significantly different. CONCLUSIONS AND CLINICAL IMPORTANCE Doxapram is more effective than caffeine for rapid correction of hypercapnia in foals with hypoxic-ischemic encephalopathy.