The Effects of Two Dosages of Midazolam on Short-Duration Anesthesia in the Harp Seal (Phoca Groenlandica)

Abstract

The purpose of this study was to provide safe anesthesia for bronchoalveolar lavage and assess the utility of premedication with i.m. midazolam for short-duration anesthesia with isoflurane in harp seals (Phoca groenlandica). Fourteen yearling harp seal pups were anesthetized three times each as part of a prospective, cross-over, blinded study. Each animal received i.m. premedication with saline, low-dose, or high-dose midazolam (respectively 0.1 and 0.2 mg/ kg). Following premedication, anesthesia was induced with 4% isoflurane in oxygen delivered through a mask and connected to a Bain non-rebreathing system. A significantly longer time was taken from the end of general anesthesia to head movement in the high-dose group compared with the saline group (P = 0.002). A significantly longer time was taken from the end of general anesthesia to ambulation in the high-dose group compared with the saline group (P = 0.006). There were no significant differences between groups in the subjective assessment of anesthetic quality or ease of intubation. Premedication with i.m. midazolam at the dosages used did prolong recovery from anesthesia, although to a degree unlikely to be significant clinically.

Wearable Near-Infrared Spectroscopy as a Physiological Monitoring Tool for Seals under Anaesthesia

“…Despite chemical immobilisation being a routine procedure in many animals, the physiological responses to anaesthetic and sedative agents in pinnipeds remains poorly understood [43]. To the best of our knowledge, this is the first study to use NIRS technology to monitor brain haemodynamics and oxygenation of pinnipeds during anaesthesia.…”

Using a combination of midazolam and butorphanol is a safe and effective reversible field sedation protocol for Weddell seal (Leptonychotes weddellii) pups

“…Depth and duration of sedation can be increased as needed by repeated administration of one or both agents. Each drug has a wide margin of safety demonstrated across taxa with minimal cardiovascular and respiratory impacts at low doses, and each has been safely and effectively used alone or in combination in a number of phocid species 1,9,12,18,24–27 . In addition, the effects of both midazolam and butorphanol can be counteracted with reversal agents.…”

Chemical immobilization protocols in free‐ranging South American fur seal (Arctocephalus australis) and adult female South American sea lion (Otaria byronia)

“…, Pang et al . , Hoskins and Arnould ) and/or combined with other anesthetics (Mellish et al . , G. Lacave).…”

“…Although several protocols of pharmacological immobilization have been described on South American otarids (Haulena 2007, F. Cirillo 2 ), we designed and tested a new protocol suitable for using in field conditions, to provide chemical immobilization with less risk of complications. For drug selection, several factors were considered including wide therapeutic margins, minimal cardiovascular and respiratory effects, good myorelaxation, and reversibility, allowing safe return to the environment where it was captured (Bowen et al 1999, Lynch et al 1999, Haulena and Heath 2001, Pang et al 2006.…”

“…Midazolam is usually used as a preanesthetic followed by inhalation anesthesia in different species of pinnipeds (McKenzie et al 2005, Pang et al 2006, Hoskins and Arnould 2013 and/or combined with other anesthetics (Mellish et al 2010, G. Lacave 6 ). Although the use of ketamine is described for Aa, 7,8 some veterinarians stopped using it because it can cause severe respiratory depression.…”