DOI
https://doi.org/10.18849/ve.v10i3.715Abstract
PICO Question
In adult dogs undergoing upper gastrointestinal (GI) endoscopy, does premedication with butorphanol compared to premedication with methadone make duodenal intubation easier?
Clinical bottom line
Category of research
Treatment.
Number and type of study designs reviewed
Two prospective, randomised, blinded, clinical trials.
Strength of evidence
Weak.
Outcomes reported
The evidence from the two studies is contradictory. One reports that premedication with butorphanol is associated with significantly quicker and easier duodenal intubation compared to methadone. The other reports that methadone is non-inferior to butorphanol for ease of duodenal intubation and did not identify a significant difference in speed or ease of duodenal intubation between premedications. Direct comparison of the studies is limited by differing anaesthetic protocols and variation between the scoring systems for ease of intubation.
Conclusion
There is insufficient evidence to support the use of butorphanol over methadone as a premedication in dogs undergoing upper GI endoscopy requiring duodenal intubation. The process of duodenal intubation may be quicker and easier with butorphanol versus methadone, but duodenal intubation can be successful with both opioids, and there is no difference in the requirement for rescue analgesia between the two drugs.
References
Donaldson, L.L., Leib, M.S., Boyd, C., Burkholder, W. & Sheridan, M. (1993). Effect of preanesthetic medication on ease of endoscopic intubation of the duodenum in anesthetized dogs. American Journal of Veterinary Research. 54(9), 1489–1495. DOI: https://doi.org/10.2460/ajvr.1993.54.09.1489
Matz, M.E., Leib, M.S., Monroe, W.E., Davenport, D.J., Nelson, L.P. & Kenny, J.E. (1991). Evaluation of atropine, glucagon, and metoclopramide for facilitation of endoscopic intubation of the duodenum in dogs. American Journal of Veterinary Research. 52(12), 1948–1950. DOI: https://doi.org/10.2460/ajvr.1991.52.12.1948
McFadzean, W.J., Hall, E.J. & van Oostrom, H. (2017). Effect of premedication with butorphanol or methadone on ease of endoscopic duodenal intubation in dogs. Veterinary Anaesthesia and Analgesia. 44(6), 1296–1302. DOI: https://doi.org/10.1016/j.vaa.2017.05.004
Salla, K.M., Lepajoe, J., Candido, M.V., Spillmann, T. & Casoni, D. (2020). Comparison of the effects of methadone and butorphanol combined with acepromazine for canine gastroduodenoscopy. Veterinary Anaesthesia and Analgesia. 47(6), 748–756. DOI: https://doi.org/10.1016/j.vaa.2020.03.008
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