Point-of-care blood ketone testing: screening for diabetic ketoacidosis at the emergency department.

INTRODUCTION: We piloted the use of a blood beta-hydroxybutyrate meter as a point-of-care testing in an emergency department (ED) to establish its role in distinguishing ketosis/ketoacidosis from simple hyperglycaemia, and develop guidelines for its use in the ED.
METHODS: 111 consecutive patients presenting with capillary glucose levels exceeding 14 mmol/L had a simultaneous blood ketone measurement at triage. This was correlated with clinical diagnosis, venous bicarbonate levels and urine ketone testing.
RESULTS: The median beta-hydroxybutyrate levels was 5.7 (range 4.3-6.0) mmol/L for patients with diabetic ketoacidosis (DKA) and 0.1 (0.0-3.2) mmol/L for the remaining patients. Only 47.7 percent could provide urine samples in the ED. A blood ketone result of 3.5 mmol/L yielded 100 percent specificity and sensitivity for the diagnosis of DKA.
CONCLUSION: This is a useful tool that allows clinicians to immediately distinguish between simple hyperglycaemia and potentially life-threatening ketotic states. We formulated simple guidelines for its utilisation in an ED setting.