Echocardiographic indices probe during dexmedetomidine/midazolam - ketamine anesthesia in dogs undergoing ovariohysterectomy

Cardiovascular and respiratory alterations during anesthesia are of major concern in canines. Thus, it is essential to understand the potential depressant effects of anesthetic drugs on cardio-vascular system; so that, anesthetic procedures are conducted in the best possible way. The objective of the study was to assess and compare the echocardiographic indices during dex-medetomidine and midazolam anesthesia in dogs undergoing elective ovariohysterectomy. Twenty-eight female dogs brought to the department for elective ovariohysterectomy were randomly divided into two groups comprising of 14 each. Sedation was achieved with dex-medetomidine and G_MID. Physiological parameters and echocardiographic indices were evaluated before drug administration (T₀), after 10 min of sedation (T₁), after induction (T₂) and at the end of surgery (T₃) in both groups. Heart rate was significantly higher at T₁, T₂ and T₃; while, rectal temperature was significantly lower at T₃ in G_MID compared to the G_DEX. There was a significant decrease in stroke volume and cardiac output values at T₁ and then, a significant increase at T₂; whereas, there was a non-significant decrease at T₃ in both groups. Ejection fraction and fractional shortening values decreased significantly at T₁, increased significantly at T₂ and then, decreased significantly at the end of surgery (T₃). Dexmedetomidine-ketamine and midazolam-ketamine combinations provide better hemodynamic and respiratory stability in the dogs undergoing elective ovariohysterectomy. Systolic functions were minimally altered with G_MID compared to G_DEX. Thus, G_MID is more cardio stable compared to G_DEX.