Sedative and cardiopulmonary effects of intranasal butorphanol with midazolam or dexmedetomidine in New Zealand white rabbits.

BACKGROUND: This study aimed to compare the sedative and cardiopulmonary effects of intranasal (IN) administration of dexmedetomidine-butorphanol (DB) and midazolam-butorphanol (MB) combinations in New Zealand white rabbits. METHODS: Eight New Zealand white rabbits were sedated by IN administration of a combination of 0.1 mg/kg dexmedetomidine and 0.4 mg/kg butorphanol (DB treatment) and 2 mg/kg midazolam and 0.4 mg/kg butorphanol (MB treatment). The electrocardiogram, pulse rate (PR), respiratory frequency (fR ), arterial haemoglobin oxygen saturation (SpO2 ), fraction of expired carbon dioxide (EtCO2 ), rectal temperature (RT), noninvasive mean arterial pressure (MAP), noninvasive systolic arterial pressure (SAP) and diastolic arterial pressure (DAP) were recorded. The onset of sedation, duration of sedation and sedation score (SS) were also noted. RESULTS: There were no significant differences in the EtCO2 , RT, MAP, SAP and DAP measurements between treatments. The PR significantly decreased in DB compared with MB over time (p = 0.001). Compared with baseline, SpO2 decreased over time in both treatments. The SS was significantly elevated over time in DB compared with MB (p = 0.002). LIMITATIONS: No pharmacokinetic information was available for either treatment, so the findings should be interpreted cautiously. CONCLUSIONS: IN DB provides more effective sedation than MB, but cardiopulmonary impairment was observed in both treatments.

Comparison of intratesticular and intramuscular administration of zolazepam-tiletamine combination on sedation, induction, and recovery qualities and vital variables in cats undergoing castration: a prospective, randomized, clinical study.

This study was aimed to compare the effects of intratesticular (IT) and intramuscular (IM) administration of the zolazepam-tiletamine (ZT) combination on sedation, induction, and recovery qualities and vital variables in cats undergoing castration. Fourteen clinically client-owned healthy cats were randomly assigned to receive 10 mg/kg ZT by either IT or IM routes. Temperament score, injection reaction score, induction time, intubation time, surgical length, anesthesia time, recovery time, and full recovery time were evaluated. Sedation score, heart rate (HR), respiratory frequency (fR), peripheral hemoglobin oxygen saturation (SpO2), mean arterial pressure (MAP), and rectal temperature (RT) variables were assessed at baseline (T0), T5, T10, T15, and T30. Median temperament score and injection reaction score were not different between groups. Induction time was significantly (p = 0.0244) shorter for the IT group (142.6 ± 29.9) than IM (290 ± 48.7 seconds). Length of anesthesia was longer in the IM group (median 290; ranged 120-540 minutes) than the IT group (median 140; ranged 98-180 minutes) (p = 0.0279). Time to standing and time to full recovery were significantly shorter in IT than IM. A recovery quality score did not significantly differ between groups (p = 0.2268). No statistically significant differences were detected between IT and IM administration regarding sedation score, HR, SpO2, MAP, and RT. The IT administration of 10 mg/kg ZT induces shorter onset of sedation and recovery time than IM administration, thereby it can be suggested for cats undergoing castration. Both administration routes produce effective sedation with limited physiological changes in anesthesia variables.

Effects of intramuscular and intranasal administration of midazolam-dexmedetomidine on sedation and some cardiopulmonary variables in New Zealand White rabbits.

OBJECTIVE: To compare the sedative and cardiopulmonary effects of intranasal (IN) and intramuscular (IM) administration of dexmedetomidine and midazolam combination in New Zealand White rabbits. STUDY DESIGN: A randomized, crossover experimental study. ANIMALS: A total of eight healthy New Zealand White rabbits, aged 6-12 months, weighing 3.1 ± 0.3 kg (mean ± standard deviation). METHODS: The animals were randomly assigned to administration of dexmedetomidine (0.1 mg kg-1) with midazolam (2 mg kg-1) by either IN or IM route separated by 2 weeks. The electrocardiogram, pulse rate (PR), peripheral haemoglobin oxygen saturation (SpO2), mean noninvasive arterial pressure (MAP), respiratory frequency (fR) and rectal temperature were measured before drug administration (baseline), T0 (onset of sedation) and at 5 minute intervals until recovery. The onset of sedation, duration of sedation and sedation score (SS) were also recorded. RESULTS: The PR was significantly lower in treatment IM than in treatment IN over time (p = 0.027). MAP < 60 mmHg developed in two and four rabbits in treatments IN and IM, respectively. SpO2 progressively decreased over time in both treatments. fR was lower than baseline at several time points in both treatments. Onset of sedation was shorter in treatment IN (90 ± 21 seconds) than in treatment IM (300 ± 68 seconds) (p = 0.036). Duration of sedation was longer in treatment IM (55.2 ± 8.7 minutes) than in treatment IN (39.6 ± 2.1 minutes) (p = 0.047). No significant difference in SS was observed between treatments (p > 0.05). CONCLUSIONS AND CLINICAL RELEVANCE: Combination of dexmedetomidine (0.1 mg kg-1) and midazolam (2 mg kg-1) decreased fR, PR and SpO2 regardless of the administration route in New Zealand White rabbits. A more rapid action and shorter duration of sedation were observed after treatment IN than after treatment IM administration.