Comparison of the efficacy of 2 sedative protocols in pediatric dogs undergoing brainstem auditory-evoked response testing.

This study compared the quality of sedation with dexmedetomidine or alfaxalone during brainstem auditory-evoked response (BAER) tests in 6- to 17-week-old dogs. This was a prospective, randomized clinical study involving 19 client-owned pediatric dogs of breeds with reported congenital deafness. Group A (GA) received alfaxalone, 2 mg/kg body weight (BW) (n = 9) and group D (GD) dexmedetomidine, 0.005 mg/kg BW, and postprocedure antagonism with atipamezole (n = 10) intramuscularly. Time from injection to sedation, duration of sedation, sedation scores, need for re-dosing, rectal temperature, pulse and respiratory rate were recorded at baseline, before and after the BAER test, and once recovered from sedation. Pulse rate was significantly lower in GD (P = 0.004) and the number of re-dosing was significantly higher in GA (P = 0.011). Both sedation protocols allowed good quality BAER test recordings in pediatric dogs. Sedation with dexmedetomidine required less re-dosing, whereas alfaxalone maintained more physiological pulse rates.

Comparaison de l'efficacité de 2 protocoles de sédation chez des chiens pédiatriques soumis à un test potentiel évoqué auditif. L'étude vise à comparer deux protocoles de sédation à base de la dexmédétomidine et de l'alfaxalone pour la réalisation de test de potentiels évoqués auditifs (PEA) chez les chiens âgés de 6 à 17 semaines. Il s'agit d'une étude clinique prospective, randomisée, incluant 19 chiens pédiatriques de propriétaire, appartenant à des races prédisposées à la surdité congénitale. Les groupe A (GA) a reçu de l'alfaxalone (2 mg/kg) (n = 9), ceux du groupe D (GD) de la dexmédétomidine (0,005 mg/kg) (n = 10), en intramusculaire. Ont été relevés : temps d'action, durée de sédation, scores de sédation, nombre de doses, température, pouls et fréquence respiratoire; au repos, avant et après le test PEA. Des différences statistiquement significatives ont été trouvées dans la fréquence du pouls, étant plus bas pour GD (P = 0,004) alors que le nombre de doses utilisées, étant supérieurs parmi GA (P = 0,011). Trois chiens avaient une surdité unilatérale. Les deux protocoles de sédation ont permis des enregistrements de bonne qualité. La sédation avec la dexmédétomidine a nécessité moins de redosage; cependant, l'alfaxalone induit un pouls cardiaque plus proche des valeurs physiologiques chez les jeunes chiens testés.(Traduit par les auteurs).

Comparison of subcutaneous sedation with alfaxalone or alfaxalone-midazolam in pet guinea pigs (Cavia porcellus) of three different age groups.

OBJECTIVE: To compare the cardiorespiratory effects, quality and duration of sedation of 2 subcutaneous sedation protocols for noninvasive procedures in guinea pigs (GPs). ANIMALS: 24 pet GPs (15 females, 9 males) of 3 different age groups: infant (n = 8), juvenile (8), and adult (8). PROCEDURES: The study design was a randomized, crossover, blinded, clinical trial with a washout period of at least 7 days between protocols. Guinea pigs were sedated SC with alfaxalone (5 mg/kg; group A) or alfaxalone (5 mg/kg) and midazolam (0.5 mg/kg; group A + M) to facilitate blood sampling, radiography, or abdominal ultrasonography. Vital parameters, hemoglobin saturation (SpO2), and sedation scores were recorded every 5 minutes. RESULTS: Mean heart rate was lower in group A than group A + M (P = 0.001), and respiratory rate was significantly (P = 0.001) decreased relative to baseline during sedation in both groups. The SpO2 remained above 95% in both sedation groups. Rectal temperature was significantly (P = 0.001) lower during recovery versus baseline. Onset of sedation was shorter and the duration longer in group A + M than in group A. The duration and depth of the sedation was different between age groups (P = 0.001), being longer and deeper in adults. Bruxism, hectic movements, twitching, and some degree of hyperreactivity were observed during 41 of the 48 sedations. CLINICAL RELEVANCE: Subcutaneous administration of alfaxalone provided reliable sedation for nonpainful procedures in GPs. When combined with midazolam, alfaxalone provided longer and deeper sedation that was more significant in adults than in younger patients.

Dural sac localization using myelography and its application to the lumbosacral epidural in dogs.

Background: The techniques described for the identification of the lumbosacral (LS) epidural space in dogs do not guarantee the needle position or an accidental subarachnoid puncture, especially in small size dogs. Aim: To determine the relationship between body weight and the location of the dural sac (DS) using myelography in dogs, and to determine the possibility of subarachnoid puncture during LS epidural based on the position of the DS. Methods: Four masked observers evaluated 70 myelographic studies of dogs, annotating the vertebrae where the DS ended, if it was localized before or after the LS space, and if accidental subarachnoid puncture during LS epidural injection was possible (yes/no). Body weight (kg) was categorized into: less than 10 kg, between 10 and 20 kg, and more than 20 kg and was also converted to body surface area (BSA) as a continuous variable. Results: The DS ended at the LS space or caudally in 50% of dogs. There was a statistically significant difference between the position of the DS and the dog's BSA (p = 0.001). The DS ended caudal to the LS space in 72.7% of dogs weighing <10 kg, in 25% of dogs between 10 and 20 kg and in 15% of dogs in the >20 kg category. The observers considered a possible subarachnoid puncture during LS epidural in 69.7% of patients <10 kg, 16.6% on those between 10 and 20 kg, and in 11.7% of the dogs >20 kg. Conclusion: The DS ended caudal to the LS space in almost 3/4 dogs in the <10 kg category, so accidental subarachnoid puncture during LS epidural is highly possible in this weight range.