Sedative-hypnotic effects of midazolam in goats after intravenous and intramuscular administration

Goats are rarely anaesthetised; consequently, scant information is available on the efficacy of anaesthetic drugs in this species. Alfaxalone is a relatively new anaesthetic agent, of which the efficacy in goats has not yet been studied. In this study, the sedative and alfaxalone sparing effects of midazolam and butorphanol, administered alone or concomitantly, in goats were assessed. Eight clinically healthy goats, four does and four wethers, were enlisted in a randomised crossover manner to receive intramuscular sedative treatments consisting of saline 0.05 mL/kg, or midazolam 0.30 mg/kg, or butorphanol 0.10 mg/kg, or a combination of midazolam 0.30 mg/kg with butorphanol 0.10 mg/kg before intravenous induction of general anaesthesia with alfaxalone. Following induction, the goats were immediately intubated and the quality of anaesthesia and basic physiological cardiorespiratory and blood-gas parameters were assessed until the goats had recovered from anaesthesia. The degree of sedation, quality of induction and recovery were scored. When compared with saline (3.00 mg/kg), midazolam,administered alone or with butorphanol, caused a statistically significant increased level of sedation and a reduction in the amount of alfaxalone required for induction (2.00 mg/kg and 1.70 mg/kg, respectively). Butorphanol alone (2.30 mg/kg) did not cause significant changes in level of sedation or alfaxalone-induction dose. During induction and recovery, the goats were calm following all treatments, including the control group. Cardiorespiratory and blood-gas parameters were maintained within clinically acceptable limits. The present study showed that midazolam, administered alone or combined with butorphanol, produces a degree of sedation that significantly reduces the dose of alfaxalone required for induction of general anaesthesia in goats, without causing any major adverse cardiorespiratory effects.

Section: Discussionsupporting

confidence: 88%

The effects of midazolam and butorphanol, administered alone or combined, on the dose and quality of anaesthetic induction with alfaxalone in goats

Dzikiti¹,

Zeiler²,

Dzikiti³

et al. 2014

J S Afr Vet Assoc

“…In a previous study, the maximal sedative effects of midazolam were observed at 5 minutes following intravenous administration (Stegmann & Bester, 2001). Although midazolam induced heavy sedation in the present study, it was likely that the maximal effect of midazolam was not achieved by the time propofol was administered.…”

Section: Discussioncontrasting

confidence: 44%

“…Midazolam has been reported to produce sedation in goats (Stegmann & Bester, 2001;Dzikiti et al 2009) and decrease the induction dose of propofol in goats (Dzikiti et al 2009). In a previous study, the maximal sedative effects of midazolam were observed at 5 minutes following intravenous administration (Stegmann & Bester, 2001).…”

Section: Discussionmentioning

confidence: 99%

Total intravenous anaesthesia (TIVA) with propofol-fentanyl and propofol-midazolam combinations in spontaneously-breathing goats

Stegmann

Veterinary Anaesthesia and Analgesia

et al. 2010

Objective To compare the efficacy and cardiopulmonary effects of propofol and fentanyl, with propofol and midazolam for total intravenous anaesthesia.Study Design Prospective, randomized, crossover experimental study.Animals Six healthy goats; 3 does and 3 wethers. ). MethodsCardiopulmonary function was well maintained with both treatments. Recovery times in minutes from the end of anaesthetic infusion for treatments FP and MP respectively were; to extubation 3.0 (3.0-3.0) and 4.5 (3.3-5.0); to sternal position, 4.5 (3.3-5.0) and 5.0 (5.0-6.5) and to standing 13.0 (10.3-15.0) and 15.0 (11.3-17.3). Quality of recovery was acceptable in both groups, but abnormal behavioural signs were observed after treatment FP. Conclusions and clinical relevanceTotal intravenous anaesthesia with propofol and fentanyl or propofol and midazolam, at the doses studied, in spontaneously-breathing, oxygen-supplemented goats is practicable. Recovery from the fentanyl-propofol combination is not always smooth.

“…This comparison shows that midazolam produces marked reductions in inhalation anaesthetic requirements for general anaesthesia in both humans and goats, with a more pronounced reduction in humans. Stegmann and Bester (2001) concluded that the sedative and hypnotic effects of intravenously administered midazolam were dose-dependent. The dosages of midazolam used in the present study are based on those of other species and are not based on pharmacokinetic data for goats since this kind of data is presently unavailable (Hall et al, 1988;Inagaki et al, 1993).…”

Section: Discussionmentioning

confidence: 99%

Effects of midazolam on isoflurane minimum alveolar concentration in goats

Stegmann

Small Ruminant Research

et al. 2011

a b s t r a c tThe effects of midazolam on the minimum alveolar concentration (MAC) of isoflurane in mechanically ventilated goats were evaluated. Six healthy goats (3 does and 3 wethers) were used in a randomized crossover design. General anaesthesia was induced with isoflurane. Endotracheal intubation was performed after which anaesthesia was maintained with isoflurane. Baseline isoflurane MAC was determined. The goats then received, on separate occasions, one of three midazolam treatments intravenously: bolus dose of 0.1 mg/kg followed by a maintenance dose of 0.1 mg/kg/h (Treatment LMID), bolus dose of 0.3 mg/kg followed by a maintenance dose of 0.3 mg/kg/h (Treatment MMID), bolus dose of 0.9 mg/kg followed by a maintenance dose of 0.9 mg/kg/h (Treatment HMID) intravenously. Isoflurane MAC was then re-determined for each midazolam treatment. The baseline [median (inter-quartile range)] isoflurane MAC in goats was 1.40 (1.38-1.41)%. Baseline isoflurane MAC was statistically significantly reduced (P < 0.05) following Treatment LMID, Treatment MMID and Treatment HMID by 16.8%, 35.1% and 54.7%, respectively. Quality of recovery from anaesthesia was good following all midazolam treatments. Midazolam, administered by constant rate infusion, significantly reduces isoflurane MAC in goats.