# Perioperative Validation of Two Handheld Glucometers in Dogs Under General Anesthesia: Analytical Robustness and Clinical Risk Assessment

## TL;DR

This study compared two handheld glucose meters in anesthetized dogs and found that a human-calibrated device was more accurate than a veterinary-specific one during surgery.

## Contribution

The study provides the first direct comparison of human and veterinary glucometers under real surgical conditions in anesthetized dogs.

## Key findings

- The human-calibrated device showed smaller differences and more consistent performance compared to a lab method.
- The veterinary-specific device overestimated glucose levels and had greater variability.
- Both devices reliably detected high blood sugar, but accuracy was reduced during anesthesia.

## Abstract

Maintaining normal blood sugar levels during anesthesia is important for the safety of dogs undergoing surgery. Both low and high blood sugar can occur during anesthesia and may affect the heart, brain, and recovery. Handheld blood glucose meters are commonly used in veterinary practice because they provide fast results using a small drop of blood. However, most previous studies evaluating these devices were performed in stable dogs, not during anesthesia, when blood flow and body temperature may change. This study compared two handheld glucose meters—one designed for humans and one designed for animals—with a laboratory method in dogs undergoing general anesthesia. The human-calibrated device showed smaller differences from the laboratory results and more consistent performance. The veterinary-specific device tended to overestimate glucose levels and showed greater variability. Although both devices were able to identify high blood sugar reliably, overall measurement accuracy was reduced during anesthesia. These findings suggest that handheld glucose meters should be carefully validated under real surgical conditions before being used for clinical decision-making in anesthetized dogs.

Accurate perioperative glucose monitoring is essential in dogs undergoing general anesthesia, yet most validation studies of handheld glucometers have been performed under stable outpatient conditions. This prospective clinical validation study evaluated the analytical agreement, diagnostic performance, and ISO 15197 compliance of a human-calibrated (Accu-Chek) and a veterinary-specific (Centrivet GK) handheld glucometer compared with a laboratory spectrophotometric reference method in 34 anesthetized dogs (99 paired measurements per device). Linear mixed-effects modeling demonstrated significant method effects (p < 0.001), with the veterinary-specific device overestimating glucose concentrations relative to the reference method (β = 20.79 mg/dL; 95% CI: 8.08–33.50; p = 0.001), whereas the human-calibrated device did not differ significantly (β = 7.18 mg/dL; 95% CI: −5.53–19.89; p = 0.267). Bland–Altman analysis showed mean bias of 4.44 mg/dL (95% CI: 0.73–8.16) for the human-calibrated device and 22.72 mg/dL (95% CI: 18.22–27.21) for the veterinary-specific device. Passing–Bablok regression identified proportional bias only for the veterinary-specific device (slope 1.19; 95% CI: 1.01–1.34). ISO compliance was 69.7% and 39.4%, respectively. For hyperglycemia detection, AUC values were 0.9566 (95% CI: 0.8955–1.0000) and 0.9757 (95% CI: 0.9479–1.0000); for hypoglycemia, 0.8567 (95% CI: 0.7557–0.9578) and 0.7376 (95% CI: 0.6056–0.8697). In anesthetized dogs, the human-calibrated device demonstrated superior analytical robustness, whereas the veterinary-specific device showed greater bias and variability.