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Home / Equine Research Bank / Vet Rec / Comparing isoflurane and desflurane: A prospective randomise...
The Veterinary record2025; doi: 10.1002/vetr.70225

Comparing isoflurane and desflurane: A prospective randomised blinded clinical trial in horses undergoing elective surgery.

Abstract: The recovery period is associated with the greatest risk of injury for horses undergoing anaesthesia. Recovery quality and duration can be influenced by the volatile agent. Methods: This prospective, randomised blinded clinical investigation recruited 101 healthy client-owned horses undergoing elective surgery at one UK equine hospital. Anaesthesia was standardised, and horses were randomly assigned to receive desflurane or isoflurane for maintenance. Horses were ventilated to normocapnia and received dobutamine to maintain mean arterial blood pressure above 60 mmHg. All the patients received romifidine intravenously prior to recovery, which was timed and video recorded to allow offline blinded evaluation by two experienced clinicians. Results: There was no significant difference between groups in haemodynamic support during anaesthesia or recovery quality. Desflurane horses recovered faster and made fewer attempts to stand. Conclusions: Nonlinearity and lack of validation of the recovery scale limit reliability; however, in the absence of a validated instrument, this scoring system is widely used. Conclusions: Haemodynamic support required during anaesthesia and recovery quality were similar between agents. Desflurane horses recovered faster and required fewer attempts to stand, suggesting that this anaesthetic may lead to fewer recovery injuries and optimise workflow in the equine theatre.
© 2025 The Author(s). Veterinary Record published by John Wiley & Sons Ltd on behalf of British Veterinary Association.
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Publication Date: 2025-12-30 PubMed ID: 41472470DOI: 10.1002/vetr.70225Google Scholar: Lookup
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  • Journal Article

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 compared the effects of two anesthetic gases, isoflurane and desflurane, on recovery quality and duration in horses undergoing elective surgery.
  • The goal was to determine which agent provides safer and more efficient recovery, potentially reducing injury risk during the vulnerable post-anesthesia period.

Study Background and Importance

  • Horses are particularly vulnerable to injury during the recovery period following anesthesia.
  • Recovery quality and duration are critical factors influencing the risk of injury and overall surgical success.
  • Different volatile anesthetic agents may affect recovery characteristics, but comparative data in horses are limited.

Study Design

  • Type: Prospective, randomized, blinded clinical trial.
  • Subjects: 101 healthy client-owned horses undergoing elective surgery at a single equine hospital in the UK.
  • Groups: Horses randomly assigned to receive either desflurane or isoflurane during maintenance of anesthesia.
  • Standardization:
    • Anaesthesia protocols were strictly standardized across horses.
    • Ventilation was controlled to maintain normal carbon dioxide levels (normocapnia).
    • Dobutamine was used to maintain stable arterial blood pressure (mean > 60 mmHg).
    • All horses received intravenous romifidine prior to recovery to aid quality of waking.
  • Assessment:
    • The recovery period was timed and video recorded for objective evaluation.
    • Two experienced clinicians, blinded to treatment group, scored recovery quality offline using a commonly used but unvalidated recovery scoring scale.

Key Findings

  • No significant difference was found between the two groups for:
    • Hemodynamic support requirements during anesthesia.
    • Recovery quality scores as assessed by the clinicians.
  • Desflurane group advantages:
    • Faster recovery times compared to the isoflurane group.
    • Fewer attempts required to stand, potentially reducing physical stress and injury risk.

Interpretation and Limitations

  • The scoring system used to evaluate recovery quality lacks formal validation and exhibits nonlinearity, which limits the precision of the findings.
  • Despite these limitations, this recovery scale is widely used in equine anesthesia studies, providing contextual comparability.
  • The similarity in hemodynamic stability means both agents are equally safe regarding vital signs during surgery.
  • The faster and smoother recovery observed with desflurane may translate into fewer injuries and more efficient surgical throughput in practice.

Conclusions and Clinical Implications

  • Desflurane appears to offer faster recovery with fewer standing attempts without compromising hemodynamic stability.
  • This suggests desflurane may reduce the incidence of recovery-associated injuries in horses, a critical consideration in equine anesthesia.
  • Improved recovery times could enhance workflow efficiency within equine surgical theaters.
  • Further research is needed with validated recovery assessment tools to confirm these findings and fully establish clinical recommendations.

Cite This Article

APA
White K, Hird J, Taylor P. (2025). Comparing isoflurane and desflurane: A prospective randomised blinded clinical trial in horses undergoing elective surgery. Vet Rec. https://doi.org/10.1002/vetr.70225

Publication

The Veterinary record
ISSN: 2042-7670
NlmUniqueID: 0031164
Country: England
Language: English

Researcher Affiliations

White, Kate
  • School of Veterinary Medicine and Science, University of Nottingham, Nottingham, UK.
Hird, John
  • Hird and Partners, Shelf Equine Hospital, Halifax, UK.
Taylor, Polly
  • Taylor Monroe, Ely, UK.

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