Banca de DEFESA: ROMULO NUNES ROCHA

Electroretinographic and electrocardiographic recordings in dogs submitted to the combination of dexmedetomidine 

and opioids.

Electrorretinography, Conscious sedation, Pets

Vision assessment is essential for diagnosing various ophthalmic pathologies that affect dogs. Electroretinography (ERG) is na assessment of retinal function to light responses and is recommended to be performed with the patient under sedation or general anesthesia to minimize the presence of ruids, however anesthetic agents can impact the results of electroretinographic waves. This study aimed to determine changes in the total field electroretinogram (ERG-ct) in dogs subjected to combination of dexmedetomidine and opioids, as well as to evaluate electrocardiographic changes and degrees of sedation. The animals were distributed into three groups. GDBUT received dexmedetomidine associated with butorphanol, GDMET received dexmedetomidine associated with methadone and GDBUP received dexmedetomidine associated with buprenorphine. GDBUT showed changes in the implicit times of waves “a” and “b” and in the response to Flicker, GDMET did not show changes to photopic stimulus, but differed in terms of Flicker. GDBUP did not present any changes. Regarding the electrocardiogram, the three groups varied in terms of heart rate and showed differences in the amplitude or duration of P wave. The GDBUT showed differences in the duration of the PR and QT intervals, amplitude of the R and T waves. In GDMET, differences were observed in PR and QT intervals and the amplitude of the T wave. The GDBUP was different in amplitudes of the P and T waves and significant differences in the PR and QT intervals. Regarding the degree of sedation, GDBUT scored higher than other groups and GDBUP was the group that scored least. It can be concluded that the animals that received the association with buprenorphine did not show changes in the values of the ERG-ct waves and suffered fewer impacts on the Ecg waves, however they were ones that presented lower rates in terms of the degree of sedation.