The use of a continuous glucose monitoring system is feasible in ill horses, according to researchers.
It may provide clinically relevant information on glucose levels, they said, but there are several challenges that need to be resolved for the system to gain more widespread usability.
Researchers with the University of Sydney and the University of Copenhagen carried out a pilot study to investigate the feasibility, management and cost of the use of a continuous glucose monitoring (CGM) system in critically ill adult horses and foals.
They compared the glucose measurements obtained by the CGM device with blood glucose concentrations.
Problems with blood glucose concentration are relatively common in critically ill horses, with hyperglycemia (high blood sugar levels) in those with acute abdominal pain linked to non-survival.
In newborn foals, high and low blood sugar levels occur with approximately equal frequency and are associated with decreased survival.
Valentina Vitale and her colleagues, writing in the journal PLOS ONE, said close monitoring of blood glucose concentrations may be useful in critically ill horses in order to optimize management and outcome.
Their study used foals aged up to two weeks and adult horses more than a year old admitted for care with clinical and laboratory parameters compatible with systemic inflammatory response syndrome (SIRS).
Glucose concentrations were monitored every four hours through blood samples with a point-of-care glucometer and with a blood gas analyzer.
A commercially made portable CGM system was also placed on six adults and four foals.
The study team reported that recordings were successfully obtained only in four adults and one foal.
Glucose concentrations corresponded fairly well between those obtained through the blood tests and the CGM, the researchers reported.
However, there appeared to be a lag time for interstitial glucose levels. Interstitial fluid is the fluid that surrounds the cells of tissue below the skin.
The authors said fluctuations of glucose in the interstitial fluid did not always follow the same trend as blood glucose.
“CGM identified peaks and drops that would have been missed with conventional glucose monitoring,” they said.
“In conclusion, the use of CGM systems is feasible in critically ill adult horses.
“Although we find some technical difficulties with the sensors in neonatal foals, other authors reported that the system was feasible also in this category of patients.
“Still, there are several challenges related to this device due to the frequent need of changing sensor, the movements of the patient that can cause the sensor to be pulled out, and the cost of the equipment.”
They said the system may provide clinically relevant information on glucose levels, but the challenges need to be resolved.
“Additional studies are needed to clarify whether there is an actual clinical benefit in terms of reducing morbidities and mortalities of performing CGM in the critically ill patient.”
Vitale V, Berg LC, Larsen BB, Hannesdottir A, Dybdahl Thomsen P, Laursen SH, et al. (2021) Blood glucose and subcutaneous continuous glucose monitoring in critically ill horses: A pilot study. PLoS ONE 16(2): e0247561. https://doi.org/10.1371/journal.pone.0247561