| Popis: |
Horses airlifted by helicopter must be cooperative, able to support their own weight plus the weight of the rescue sling, nonreactive to helicopter approach, hovering, lift-off, and transport; and able to support their own weight without significant ataxia during delivery to safe ground. The flooding that occurs in Louisiana has given us the opportunity to be involved in airlift rescue of eight horses stranded by high water. In our experience, the effective titration of sedatives is best accomplished through an IV catheter placed in one of the jugular veins rather than by repeated IV injections. Prior to the catheter placement, we sedate the horses with either xylazine (0.4–0.5 mg kg−1 IV) or detomidine (8–10 µg kg−1 IV). The process of airlifting can be divided into four phases: (1) attachment of lift sling; (2) helicopter approach and hover during attachment of the sling to the aircraft; (3) lift and transport; and (4) delivery to safe zone. The IV administration of an additional 0.4–0.5 mg kg−1 of xylazine immediately prior to placing the horse in the lift sling produces an appropriate level of sedation without excessive ataxia. With the sling in place and the horse blindfolded, the helicopter is called. As the helicopter approaches, another 0.4–0.5 mg kg−1 xylazine administered. The IV is generally sufficient to prevent reaction to the noise and wind associated with the hovering of the helicopter. After the lift sling is connected to the helicopter, a final dose of xylazine (0.25 mg kg−1 IV) has proven effective in reducing reaction to lift and transport. This sedation protocol has proven effective for airlifts of approximately 5–10-minutes duration. Thus sedated, horses are able to support their weight without excessive ataxia when delivered to their destination. Xylazine appears to be more effective than detomidine because of its shorter latency of onset and duration of action. |
