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Evaluation of the Effects of Detomidine on Equine Myoelectrical Activity Using Electrointestinography.

Abstract: To evaluate the effects of detomidine on equine intestinal slow-wave activity and frequency distribution measured by electrointestinography (EIG). Methods: Prospective, experimental study. Methods: University teaching hospital. Methods: A convenience sample of twelve 7- to 21-year-old clinically normal horses. Methods: Horses were randomly assigned to saline control (four horses) or detomidine treatment (eight). After obtaining a 30-min baseline EIG, a saline or detomidine bolus was administered, followed by a constant rate infusion, and another EIG was recorded. Ultrasonographic examinations monitored cecal and left ventral colon contractions. Spectral analysis was performed to evaluate changes in dominant frequency, dominant power, total power, percent frequency distribution, and changes in slow-wave rhythmic activity. Results: Median (interquartile range [IQR]) dominant frequency in cycles per minute (cpm) was similar for the cecum (2.4 cpm; IQR: 0.51 cpm) and left ventral colon (2.13 cpm; IQR: 0.16 cpm) and unchanged by either treatment (P > 0.074). Compared with saline, which was unchanged, detomidine reduced dominant power ratios for both cecum (0.45; IQR: 0.18) and left ventral colon (0.63; IQR: 0.35; P = 0.002). Detomidine decreased total power for the cecum in the 2-4 cpm frequency range from 55.0% (IQR: 4.4%) to 43.1% (IQR: 6.7%) and for the left ventral colon from 54.4% (IQR: 5.5%) to 27.3% (IQR: 9.3%; P  0.08). Dominant power correlated with the rate of contractions measured ultrasonographically (P < 0.001). Conclusions: Detomidine decreased dominant power ratios for both the cecum and left ventral colon and produced tachyarrhythmias in cecal slow-wave activity. The correlation of dominant power with intestinal contractions supports the clinical development of EIG to diagnose equine motility disorders.
Publication Date: 2025-04-20 PubMed ID: 40254911PubMed Central: PMC12065429DOI: 10.1111/vec.13464Google Scholar: Lookup
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  • Journal Article
  • Randomized Controlled Trial
  • Veterinary

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.

The research examines the effects of detomidine, a medication often used in equine medicine, on the activity of horse intestines, using a technique called electrointestinography (EIG). The study found that detomidine decreased power ratios of the cecum and left ventral colon and caused increased heart rate in cecal (a portion of the large intestine) slow-wave activity.

Study Methods and Participants

  • The research was a prospective, experimental study conducted at a university teaching hospital.
  • It involved twelve clinically normal horses aged between 7 and 21 years.
  • The horses were randomly assigned to either a control group (which received a saline solution) or a treatment group (which received detomidine).
  • Before and after the administration of either the saline or detomidine, an EIG was performed to measure the electrical activity in the intestines. Ultrasonographic examinations were also used to monitor contractions in the cecum and left ventral colon.

Data Analysis

  • A spectral analysis was conducted to evaluate changes in dominant frequency, dominant power, total power, percent frequency distribution, and changes in slow-wave rhythmic activity.
  • The results from the saline group were then compared to those from the detomidine group to determine the effects of the drug.

Results and Conclusion

  • The study’s results showed that the dominant frequency in the cecum and left ventral colon was similar and was not changed by either treatment.
  • Detomidine, however, reduced the dominant power ratios in both the cecum and left ventral colon compared to the saline solution, which showed no change.
  • The total power for the cecum was decreased in the 2-4 cpm frequency range and for the left ventral colon with detomidine. However, there was an increase for the cecum in the 8-12 cpm frequency range.
  • There were no changes in frequency distribution noted for the controls.
  • The dominant power was found to be correlated with the rate of contractions measured with ultrasonography.
  • From these results, the researchers concluded that detomidine decreased the dominant power ratios for both the cecum and left ventral colon, and it caused a form of tachycardia (increased heart rate) in cecal slow-wave activity.
  • The correlation between dominant power and intestinal contractions could be useful in developing EIG techniques to diagnose equine motility disorders in clinical settings.

Cite This Article

APA
Munsterman AS, Dias Moreira AS, Kottwitz J. (2025). Evaluation of the Effects of Detomidine on Equine Myoelectrical Activity Using Electrointestinography. J Vet Emerg Crit Care (San Antonio), 35(2), 120-130. https://doi.org/10.1111/vec.13464

Publication

ISSN: 1476-4431
NlmUniqueID: 101152804
Country: United States
Language: English
Volume: 35
Issue: 2
Pages: 120-130

Researcher Affiliations

Munsterman, Amelia S
  • Department of Large Animal Clinical Sciences, College of Veterinary Medicine, Michigan State University, East Lansing, Michigan, USA.
Dias Moreira, Ana S
  • Department of Large Animal Clinical Sciences, College of Veterinary Medicine, Michigan State University, East Lansing, Michigan, USA.
Kottwitz, Jack
  • Department of Large Animal Clinical Sciences, College of Veterinary Medicine, Michigan State University, East Lansing, Michigan, USA.
  • Department of Pharmacology and Toxicology, Michigan State University, East Lansing, Michigan, USA.

MeSH Terms

  • Animals
  • Horses / physiology
  • Imidazoles / pharmacology
  • Female
  • Male
  • Electromyography / veterinary
  • Prospective Studies
  • Cecum / drug effects
  • Cecum / physiology
  • Colon / drug effects
  • Colon / physiology
  • Gastrointestinal Motility / drug effects

Grant Funding

  • Veterinary Emergency and Critical Care Society Research Grant
  • University of Wisconsin Companion Animal Fund

Conflict of Interest Statement

The authors declare no conflicts of interest.

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