EFFECTS OF DEXMEDETOMIDINE ON HEMATOLOGICAL, PHYSIOLOGICAL PARAMETERS AND SEDATION IN HEALTHY DOGS

Abstract

 The present study aimed to evaluate the effects of dexmedetomidine on hematological, physiological, and sedation parameters in healthy dogs. For this purpose, seven healthy mixed-breed dogs with a median body weight of 16 (1.5–26.0) kg and a median age of 1.8 (1.0–5.0) years were included in the study. Sedation score (0–14), heart rate, respiratory rate, rectal temperature, and complete blood count were assessed before (T0) and 15 minutes after (T15) intramuscular administration of dexmedetomidine (90 µg/m²). The drug induced significant sedation (p = 0.01), accompanied by bradycardia (T0 = 119 ± 27 bpm; T15 = 70 ± 19 bpm; p < 0.01) and a reduction in respiratory rate (T0 = 40 ± 17 breaths/min; T15 = 22 ± 7 breaths/min; p = 0.03), without affecting body temperature. Hematological analysis revealed decreases in packed cell volume (T0 = 50.3 ± 4%; T15 = 47.1 ± 3%; p = 0.01), total plasma protein concentration (T0 = 7.7 ± 0.9 g/dL; T15 = 7.1 ± 0.7 g/dL; p < 0.01), and monocyte count (T0 = 0.4 ± 0.2 × 10³/µL; T15 = 0.29 ± 0.1 × 10³/µL; p < 0.01). Conversely, total leukocyte count (T0 = 11.6 ± 3 × 10³/µL; T15 = 12.5 ± 3 × 10³/µL; p < 0.01) and segmented neutrophil count (T0 = 7.0 ± 1.5 × 10³/µL; T15 = 7.9 ± 2.1 × 10³/µL; p = 0.03) increased. Dexmedetomidine produces sedation accompanied by bradycardia and reduced respiratory rate. In blood cells, it decreases the packed cell volume, total plasma protein concentration, and monocyte count, while increasing total leukocyte count through an elevation in circulating neutrophils.