Review of Midazolam Sedation in Reptiles at the National Aquarium, Baltimore
Benzodiazepine midazolam is commonly utilized as a sedative and muscle relaxant in veterinary medicine and has been used in a variety of species as a single-agent or part of multi-drug sedation or general anesthesia protocol. A benzodiazepine antagonist, flumazenil, is readily available in the United States. Midazolam use has been reported in reptiles, often as part of a multi-drug protocol for general anesthesia, with variable sedative effects as a single agent.1-3
This is a retrospective review of midazolam sedation, excluding general anesthesia, at the National Aquarium, Baltimore, between January 1, 2009, and February 1, 2011. There were 32 events in 23 reptiles: 12 turtles, 5 snakes, 5 lizards, and 1 crocodile. Midazolam was used primarily to facilitate handling of animals during diagnostic procedures (e.g., radiographs), wound care, or abscess debridement. Average dosage was 0.3 mg/kg IM (range 0.1–1.0 mg/kg). Concurrent use of analgesics (e.g., lidocaine) occurred in 44% of events. Overall, desired clinical sedation was achieved in 84% of events. Duration of sedation was typically 10 to 30 minutes but was not reported consistently. Flumazenil was utilized to antagonize midazolam in 50% of events.
Midazolam alone or with analgesia should be considered to facilitate restraint of reptile for procedures. Clinicians considered it effective in a variety of species. Midazolam use has been well-received by husbandry and technician staff and is perceived to reduce stress associated with handling and improve quality of diagnostic procedures.
The authors would like to thank National Aquarium Baltimore Animal Health Department veterinary technicians Christine Steinert, CVT, and Sarah McMillen, CVT, for their assistance.
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