Archives of Disease in Childhood | 2019
P265\u2005The reliability of point of care ketone measurement in the paediatric hypoglycaemia setting
Abstract
Introduction Point of care capillary ketone (beta-hydroxybutyrate) measurement is often used in the management of paediatric dysglycaemia. The accuracy of point of care ketone (POCK) measurement has not been evaluated in the setting of paediatric hypoglycaemia. This study aimed to assess the accuracy of POCK measurement compared to gold-standard laboratory plasma ketone (PK) measurement in a population of infants and children presenting to a paediatric emergency department. Methods This retrospective study was conducted between January-December 2017 in the Emergency Department (ED) at Children’s University Hospital (CUH), Temple Street, Dublin, Ireland. The ED recorded 54,222 attendances during the study period and all hypoglycaemia screens performed in the study period were reviewed. PK values were extracted from laboratory records. POCK results were retrieved from patient’s electronic emergency department medical records. Where data was incomplete (either POCK or PK measurement were not recorded), results were excluded from the analysis. Results were also excluded where greater than thirty minutes had elapsed between POCK and PK measurement. The agreement between the two methods of ketone measurement was analysed using a Bland-Altman plot. The difference between mean POCK and PK were analysed using a paired t-test. Results A total of 34 hypoglycaemia screens were performed in ED during the study period. Of these, 15 screens were excluded (two because of incomplete data and 13 because of a time interval of greater than thirty minutes between POCK and PK measurement). 19 screens were included in the analysis. No significant difference was seen between mean PK (3.39± 1.66 mmol/L) and mean POCK (4.28 ± 1.62), with a mean difference of -0.30 ± 0.54 mmol/L (95% CI, -0.364 to -0.243; p=0.032) No significant proportional bias was seen between POCK and PK levels on Band-Altman plot. Discussion This study provides evidence for the use of POCK as a reliable surrogate for PK in the setting of hypoglycaemia in paediatric patients. Accurate POCK measurement is very useful in the diagnosis and management of paediatric hypoglycaemia. In the paediatric ED, children presenting with hypoglycaemia often do so during episodes of intercurrent illness where dehydration is common, and phlebotomy is challenging. Furthermore, when faced with a small child with hypoglycaemia, timely correction of hypoglycaemia is an urgent priority. While not a substitute for formal diagnostic tests, POCK measurements are quick and easy to obtain, can direct appropriate investigation and allow sample prioritisation where sample volume is limited.