Abstract: The prevalence and nature of arrhythmias in horses following general anaesthesia and surgery is poorly documented. It has been proposed that horses undergoing emergency surgery for gastrointestinal disorders may be at particular risk of developing arrhythmias. Our primary objective was to determine the prevalence and nature of arrhythmias in horses following anaesthesia in a clinical setting and to establish if there was a difference in the prevalence of arrhythmias between horses with and without gastrointestinal disease undergoing surgery. Our secondary objective was to assess selected available risk factors for association with the development of arrhythmias following anaesthesia and surgery. Methods: Horses with evidence of gastrointestinal disease undergoing an exploratory laparotomy and horses with no evidence of gastrointestinal disease undergoing orthopaedic surgery between September 2009 and January 2011 were recruited prospectively. A telemetric electrocardiogram (ECG) was fitted to each horse following recovery from anaesthesia and left in place for 24 hours. Selected electrolytes were measured before, during and after surgery and data was extracted from clinical records for analysis. Recorded ECGs were analysed and the arrhythmias characterised. Multivariable logistic regression was used to identify risk factors associated with the development of arrhythmias. Results: Sixty-seven horses with gastrointestinal disease and 37 without gastrointestinal disease were recruited. Arrhythmias were very common during the post-operative period in both groups of horses. Supra-ventricular and bradyarrhythmias predominated in both groups. There were no significant differences in prevalence of any type of arrhythmias between the horses with or without gastrointestinal disease. Post-operative tachycardia and sodium derangements were associated with the development of any type of arrhythmia. Conclusions: This is the first study to report the prevalence of arrhythmias in horses during the post-operative period in a clinical setting. This study shows that arrhythmias are very common in horses following surgery. It showed no differences between those horses with or without gastrointestinal disease. Arrhythmias occurring in horses during the post-anaesthetic period require further investigation.
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This study examines the occurrence and characteristics of heart rhythm problems (arrhythmias) in horses following anaesthesia and surgery. It finds that such issues are common, regardless of whether the horses were treated for gastrointestinal disease, and identifies rapid heart rate and sodium imbalances as related risk factors.
Objectives and Methods of the Research
The main aim of this research was to determine the occurrence and nature of arrhythmias in horses after they had received anaesthesia in a clinical setting. The scientists were especially interested to see if there was a difference in the extent of arrhythmias between horses with and without gastrointestinal disease who underwent surgery.
The secondary objective was to evaluate available risk factors associated with the emergence of arrhythmias following anaesthesia and surgery.
The study was conducted on horses showing signs of gastrointestinal disease that were undergoing an investigative abdominal surgery (exploratory laparotomy) and horses with no gastrointestinal issues undergoing orthopaedic surgery.
Using a telemetric electrocardiogram (ECG), the horses’ hearts were monitored for 24 hours after they woke up from anaesthesia. At the same time, selected electrolytes were measured before, during and after surgery for possible correlation with the development of arrhythmias.
The ECG recordings were then analysed and the arrhythmias characterised. A statistical technique (multivariable logistic regression) was used to identify risk factors connected to the development of arrhythmias.
Results of the Study
Arrhythmias were found to be common during the post-operative period in both groups of horses, those with gastrointestinal disease and those without.
The main types of arrhythmia observed were supra-ventricular (originating above the heart’s main pumping chambers) and bradyarrhythmias (slow heart rate).
There were no significant differences in the occurrence of any type of arrhythmia between the horses with or without gastrointestinal disease.
Rapid post-operative heart rate (tachycardia) and imbalances in the sodium level were associated with the development of any type of arrhythmia.
Conclusions
This research is the first to report the occurrence of arrhythmias in horses in a clinical setting during the post-operative period.
The results showed that arrhythmias are very common in horses following surgery, with no significant differences between those with or without gastrointestinal disease.
The study suggests that more investigation is needed into arrhythmias occurring in horses during the post-anaesthetic period.
Cite This Article
APA
Morgan RA, Raftery AG, Cripps P, Senior JM, McGowan CM.
(2011).
The prevalence and nature of cardiac arrhythmias in horses following general anaesthesia and surgery.
Acta Vet Scand, 53(1), 62.
https://doi.org/10.1186/1751-0147-53-62
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