Monitoring heart-rate variability in horses with colic could well prove helpful in assessing the possible outcome, the findings of fresh research suggest.
Colic, a cause of acute abdominal pain in horses, is a major cause for emergency treatment. It is associated with high stress levels in affected horses, leading to an increased serum cortisol concentration.
Stress can also be assessed by analyzing heart rate variability.
Researchers, in a study conducted at the Free University of Berlin, set out to investigate whether the stress level was different between horses with different causes of colic pain and, therefore, demanding a different treatment strategy.
The work by Professor Heidrun Gehlen and her colleagues centered on 43 horses admitted to two equine referral hospitals.
The horses were categorized into three groups according to the treatment — surgical, conservative and euthanized. Heart-rate variability and laboratory variables in blood, including cortisol concentrations, were measured at admission, the day after admission, and at discharge.
Heart rate, its variability over time, and cortisol levels indicated a decrease in the stress level the day after admission and on the day of discharge for the conservatively and surgically treated horses. This indicates a decreased sympathetic stimulation over time in these two groups.
However, such changes over time were not seen in horses ultimately euthanized during their hospitalization. Indeed, the differences in the parameters between horses that were eventually euthanized and those that survived were most obviously visible on the day after admission, the study team reported in the open-access journal Animals.
“We concluded that heart-rate variability can give further important information on the stress level in horses with colic and might be helpful in assessing possible outcome,” they said. “However, further studies are required to assess the validity of heart-rate analyses in horses with colic.”
Turning to the wider blood work, the authors noted that plasma lactate was the only variable that constantly differed in group that was euthanised from the two groups that survived.
This, they said, underscored the importance of evaluating plasma lactate in the assessment of the severity of diseases in horses with colic.
The study team comprised Gehlen, Maria-Dorothee Faust and Dagmar Trachsel, all with the Free University of Berlin; and Remigiusz Grzeskowiak, with the University of Tennessee.
Gehlen, H.; Faust, M.-D.; Grzeskowiak, R.M.; Trachsel, D.S. Association Between Disease Severity, Heart Rate Variability (HRV) and Serum Cortisol Concentrations in Horses with Acute Abdominal Pain. Animals 2020, 10, 1563.