The hospital and home use of a 30-second hand-held blood ketone meter: guidelines for clinical practice

Aims To establish the role of the measurement of beta -hydroxybutyrate (bet a -OHB) in distinguishing simple hyperglycaemia from ketosis, and as an ind icator of adequate resolution of ketoacidosis, using an electrochemical blo od ketone meter. The aim of the study is to assess the accuracy and precisi on of the meter and to develop clinical guidelines for the use of the keton e meter at home and in hospital. Patients and methods Twenty patients with poor glycaemic control (mean HbA( 1c) 10.2%) were recruited from the diabetes clinic and 14 patients admitted with diabetic ketoacidosis (DKA) were recruited from two Accident and Emer gency Departments. The blood obtained at each routine fingerprick test for glucose measurement was tested for beta -OHB using the ketone meter. Plasma beta -OHB concentrations were also measured on admission using a laborator y enzymatic method. Results Paired glucose and beta -OHB meter readings (n = 1099) in clinic pa tients demonstrated that, in the absence of intercurrent illness, beta -OHB levels did not exceed 1 mmol/l, irrespective of glucose readings. In the 1 4 ketoacidotic patients, the mean plasma beta -OHB concentration, measured in the laboratory, on admission was 7.4 mmol/l (range 3.9-12.3 mmol/l). The median half-life of beta -OHB was 1.64 h (1st IQR 2.27 h, 3rd IQR 1.34 h). The median time taken, from the initiation of treatment, for beta -OHB con centrations to fall to below 1 mmol/l was 8.46 h (range 5-58.33 h). Conclusion Near patient blood ketone testing is a useful adjunct to blood g lucose monitoring in distinguishing between ketosis and simple hyperglycaem ia. The data suggest that beta -OHB levels greater than or equal to 1 mmol/ l require further action and levels > 3 mmol/l necessitate medical review. In addition, the rate of fall of beta -OHB in DKA can be used as an indicat or of the adequacy of treatment.