FREE SHIPPING over $40
OVER 10000 FIVE-STAR REVIEWS
5% OFF ALL SUBSCRIPTIONS
100% HAPPINESS GUARANTEE
Analyze Diet
0
Journal of zoo and wildlife medicine : official publication of the American Association of Zoo Veterinarians2026; 57(2); 406-411; doi: 10.1638/2025-0122

USE OF GUAIFENESIN-KETAMINE-XYLAZINE INFUSION FOR MAINTENANCE OF ANESTHESIA IN CAPTIVE PREZEWALSKI HORSES (EQUUS FERUS PRZEWALSKI ): A CASE SERIES.

Abstract: This case series documents the use of triple drip, a combination of IV guaifenesin, ketamine, and xylazine (GKX) to extend the length of anesthesia in zoo-owned Przewalski horses (). In three separate procedures involving two different animals, GKX was used to prolong and deepen the plane of anesthesia for 90 to 120 min beyond an initial induction dart containing ketamine, butorphanol, azaperone, and medetomidine. The depth of anesthesia was sufficient to permit surgical excision of SC abscesses and other procedures. Throughout the anesthetic events, the horses breathed spontaneously and maintained normal cardiorespiratory parameters, demonstrated no response to noxious stimuli, and had excellent muscle relaxation. Recoveries were smooth in all cases. Development of anesthetic protocols without ultrapotent opioids has become a priority in zoological medicine due to decreased drug availability as well as safety considerations. This is the first report of an entirely ultrapotent narcotic-free anesthetic protocol for intermediate to extended length procedures in Przewalski horses.
Get Full Text
Publication Date: 2026-07-06 PubMed ID: 42405720DOI: 10.1638/2025-0122Google Scholar: Lookup
The Equine Research Bank provides access to a large database of publicly available scientific literature. Inclusion in the Research Bank does not imply endorsement of study methods or findings by Mad Barn.
LinkedInCopy
  • Journal Article
  • Case Reports

Summary

This research summary has been generated with artificial intelligence and may contain errors and omissions. Refer to the original study to confirm details provided. Submit correction.

Overview

  • This study reports on the successful use of a combination intravenous infusion (triple drip) containing guaifenesin, ketamine, and xylazine to maintain extended general anesthesia in captive Przewalski horses during surgical procedures.
  • The protocol avoided the use of ultrapotent opioids, providing a safe and effective anesthetic approach with stable vital signs and smooth recoveries in zoo settings.

Background

  • Przewalski horses (Equus ferus przewalskii): Wild horses often managed in captivity for conservation.
  • Anesthesia challenges: Captive wild equids require safe, effective anesthesia for surgical and diagnostic procedures.
  • Traditional anesthetics: Usually involve opioids, but these drugs are becoming harder to obtain and have safety concerns in zoo environments.
  • Need for alternative protocols: Development of opioid-free methods is important for zoological medicine.

Objectives

  • To evaluate the effectiveness of an intravenous triple drip infusion of guaifenesin, ketamine, and xylazine (GKX) to maintain anesthesia for intermediate to extended durations in Przewalski horses.
  • To document clinical outcomes including anesthetic depth, physiological stability, and recovery quality.

Methods

  • Setting: Zoo environment involving captive Przewalski horses.
  • Animals: Two different Przewalski horses undergoing three procedures in total.
  • Induction: Initial dart containing ketamine, butorphanol, azaperone, and medetomidine was used.
  • Maintenance: Following induction, an intravenous infusion of guaifenesin, ketamine, and xylazine (GKX) administered to maintain anesthesia.
  • Duration: Anesthesia prolonged 90 to 120 minutes beyond initial induction.
  • Monitoring: Cardiorespiratory parameters and depth of anesthesia observed throughout.
  • Procedures performed: Surgical excision of subcutaneous abscesses and other procedures requiring deep anesthesia.

Results

  • Depth of anesthesia: Sufficient to prevent response to painful stimuli and to allow surgical intervention.
  • Muscle relaxation: Excellent, facilitating surgical manipulations.
  • Spontaneous breathing: Maintained consistently, indicating stable respiratory function.
  • Cardiorespiratory stability: Normal parameters observed during anesthesia, suggesting good physiological tolerance.
  • Recoveries: All animals recovered smoothly without complications.

Significance

  • This report presents the first documented use of an ultrapotent narcotic-free anesthesia protocol for medium to extended length procedures in Przewalski horses.
  • The protocol addresses drug availability and safety challenges associated with opioids in zoo medicine.
  • It offers a practical alternative for veterinarians managing anesthesia in wildlife species requiring intermediate duration surgical anesthesia.

Conclusion

  • The guaifenesin-ketamine-xylazine infusion (GKX) triple drip is an effective, safe, and opioid-free method for maintaining anesthesia in captive Przewalski horses for up to two hours.
  • The technique ensures stable vital signs, adequate anesthetic depth, optimal muscle relaxation, and smooth recoveries.
  • This approach can help improve anesthetic protocols in zoological medicine where opioids may be restricted or undesirable.

Cite This Article

APA
Hausmann J, Wiedner E, Hinkle S, Johnson JG. (2026). USE OF GUAIFENESIN-KETAMINE-XYLAZINE INFUSION FOR MAINTENANCE OF ANESTHESIA IN CAPTIVE PREZEWALSKI HORSES (EQUUS FERUS PRZEWALSKI ): A CASE SERIES. J Zoo Wildl Med, 57(2), 406-411. https://doi.org/10.1638/2025-0122

Publication

Journal of zoo and wildlife medicine : official publication of the American Association of Zoo Veterinarians
ISSN: 1042-7260
NlmUniqueID: 8915208
Country: United States
Language: English
Volume: 57
Issue: 2
Pages: 406-411

Researcher Affiliations

Hausmann, Jennifer
  • The Denver Zoo Conservation Alliance, Denver, CO 80205 USA.
Wiedner, Ellen
  • Hyrax Veterinary Consulting, Durango 82301 USA, ebwvmd@yahoo.com.
Hinkle, Stephanie
  • The Denver Zoo Conservation Alliance, Denver, CO 80205 USA.
Johnson, James G
  • The Denver Zoo Conservation Alliance, Denver, CO 80205 USA.

MeSH Terms

  • Animals
  • Female
  • Male
  • Anesthetics, Combined / administration & dosage
  • Anesthetics, Dissociative / administration & dosage
  • Anesthetics, Intravenous / administration & dosage
  • Animals, Zoo
  • Guaifenesin / administration & dosage
  • Horses
  • Hypnotics and Sedatives / administration & dosage
  • Ketamine / administration & dosage
  • Xylazine / administration & dosage

References

This article includes 26 references
  1. Aarnes TK, Lerche P, Bednarski RM, Hubbell JA. Total intravenous anesthesia using a midazolamketamine-xylazine infusion in horses: 46 cases (2011–2014). Canadian Vet J 2018;59(5):500–504.
  2. Abrahamsen EJ. Chemical restraint, anesthesia, and analgesia for camelids. Vet Clinics: Food Anim Pract 2009;25(2):455–494.
  3. Bertelsen MF. Giraffidae. In: Fowler's zoo and wild animal medicine, Volume 8, St. Louis (MO): Elsevier; 2014. p. 602–610.
  4. Black PA, Keller DL, Burton MS, Martel C. Evaluation of two anesthetic combinations in lowland nyala (). J Zoo Wildl Med 2020;51(2): 290–296.
  5. Bohner J, Painer J, Bakker D, Haw AJ, Rauch H, Greunz EM, Egner B, Goeritz F. Immobilization of captive Kulans () without using ultrapotent opioids. Frontiers Vet Sci 2022. Article 885317.
  6. Budde JA, McCluskey DM. Guaifenesin, Intravenous. In: Plumb's Veterinary Drug Handbook, 10th edition. John Wiley & Sons; 2023. pp. 598–600.
  7. Fontenot D, Mylniczenko N, Fleming G. Utilization of continuous rate infusion, manually controlled infusion, and total intravenous infusion for anesthesia and analgesia in zoological collections. In: Proc Am Assoc Zoo Vet. 2012. p. 9–17.
  8. Hansen CM, Beckmen KB. Butorphanol-azaperone-medetomidine for the immobilization of captive caribou () in Alaska, USA. J Wildl. Dis. 2018;54(3):650–652.
  9. Hubbell JA. How to get 15 minutes more out of your field anesthesia technique. In: Proc Am Assoc Equine Pract. 2018;64:273–275.
  10. Janssen D, Oosterhuis J. Guaifenesin for muscle relaxation in immobilized hoofstock. Proc Am Assoc Zoo Vet, 1984.
  11. Kummrow MS. Ratites or Struthioniformes: Struthiones, Rheae, Cassuarii, Apteryges (ostriches, rheas, emus, cassowaries, and kiwis), and Tinamiformes (tinamous). Fowler's Zoo and Wild Animal Medicine, Volume 8. St Louis (MO)2015. p. 75–82.
  12. Lamglait B, Lair S, Brodeur V, Côté SD, Taillon J. Physiological parameters in free-ranging muskoxen () anesthetized with butorphanol-azaperone-medetomidine and etorphine-xylazine +/– butorphanol. Zoo and Wildlife Health Conf 2020.
  13. Milnes EL, Skelding AM, Larouche CB, Ferro A, Dutton C, Anderson N. Ketamine-butorphanol-azaperone-medetomidine as an alternative to ultrapotent opioid anesthesia in zoo takhi (). In: Proc Am Assoc of Zoo Vet, 2023.
  14. Pergolizzi J, Magnusson P, LeQuang JAK, Breve F. Illicitly manufactured fentanyl entering the United States. Cureus 2021;13(8), e17496.
    doi: 10.7759/cureus.17496google scholar: lookup
  15. Queiroz-Telles F, Bonifaz A, Rossow J, Chindamporn A. Sporothrix and sporotrichosis. In: Encyclopedia of Infection and Immunity. Vol. 2, Elsevier Oxford, 2022. pp. 376–396.
  16. Seddighi R, Doherty TJ. Field sedation and anesthesia of ruminants. Vet Clinics: Food Anim Pract 2016;32(3):553–570.
  17. Semjonov A, Raath JP. Newer anesthetic combinations including local anesthesia. In: Fowler's Zoo and Wild Animal Medicine Current Therapy, Volume 10. Elsevier; St Louis (MO) 2023. pp. 347–354.
  18. Shury T, Lance W, Hunter D. Butorphanol, azaperone and medetomidine (BAM) for field immobilization of plains bison. Proc Wildl Dis Assoc Annual General Mtg 2016.
  19. Siegal-Willott JL, Bauer KL, Hayek L-AC, Luensman NM, Cross TN, Sajecki JL, McRuer DL. Comparison of isoflurane gas versus a guaifenesin, ketamine, and medetomidine constant-rate infusion for maintenance anesthesia in American black bears (). J Zoo Wildl Med 2019;50(3):570–578.
  20. Sinclair M. Equine field anesthesia with triple drip mixtures. In: 65th Convention of the Canadian Vet Med Assoc, 2013.
  21. Staffieri F, Driessen B. Field anesthesia in the equine. Clin Tech Equine Pract 2007;6(2):111–119.
  22. Stemmet GP, Meyer LC, Bruns A, Buss P, Zimmerman D, Koeppel K, Zeiler GE. Compared to etorphine–azaperone, the ketamine–butorphanol–medetomidine combination is also effective at immobilizing zebra (). Vet Anaesth & Analg 2019;46(4): 466–475.
  23. Stuchin M, Mama KR, Zuba JR, Oosterhuis JE, Lamberski N, Olea-Popelka F. A comparison of opioid-based protocols for immobilization of captive Grevy's zebra (). J Zoo Wildl Med 2019;50(1):258–261.
  24. Vonfeld I, Leclerc A, Zilberstein L, Pérot M, Avril S, Lamglait B, Ordonneau D, Thorel M, Ménagerie L, Hennet P. Total intravenous anaesthesia maintenance with an infusion of butorphanol, ketamine and guaifenesin in two greater one-horned rhinoceros (). Vet Rec Case Rpt 2024, e920.
  25. Walzer C, Stadler G, Petit T, Sos E, Molnar V, Brabender K, Fluch G. Surgical field anesthesia in Przewalski's horse () in Hortobagy National Park, Hungary. Proc Am Assoc Zoo Vet 2009; 98–99.
  26. Yamashita K, Muir WW. Intravenous anesthetic and analgesic adjuncts to inhalation anesthesia. In: Equine Anesthesia. Monitoring and Emergency Therapy, 2nd Ed., Saunders Elsevier, St Louis (MO) 2009;260–276.

Citations

This article has been cited 0 times.
Subscribe to our newsletter
Join 106,387 horse owners like you who receive our email updates on horse health and nutrition.