Inaccurate point-of-care blood glucose measurement in a dog with secondary erythrocytosis.

Background: Point-of-care (POC) portable blood glucose meters (PBGMs) are convenient and inexpensive tools for assessing patient blood glucose concentrations. They are often used to quickly diagnose hypoglycemia or collect serial glucose readings in diabetic patients. However, POC meters have been previously identified in human and veterinary literature to be inaccurate when utilized in patients with abnormal HCT. This problem may not be reflected in manufacturer guidelines referenced by practitioners in the POC setting.

Key Findings: A 1.5-year-old dog, previously diagnosed with multiple congenital cardiac malformations, right-to-left cardiac shunting and secondary erythrocytosis, presented to a veterinary emergency center minimally responsive and without detectable pulses. PBGM measurement identified hypoglycemia. Following stabilization of the dog, serial glucose assessments showed discordant results between PBGMs and the reference laboratory biochemistry analyzer. A pathological cause for hypoglycemia was not identified and PBGM readings were determined to be erroneously low due to the dog's abnormally high HCT.

Significance: This case demonstrates the limitations of using PBGMs to assess blood glucose in a dog with secondary erythrocytosis. The report emphasizes the need for judicious use of PBGMs in critically ill patients and that these glucometers may not be reliable in patients with abnormal HCT values.