title: Bedside monitoring of blood beta-hydroxybutyrate levels in the management of diabetic ketoacidosis in children.
abstract: BACKGROUND
  Diabetic ketoacidosis (DKA) affects many children with type 1 diabetes. Insulin treatment of DKA is traditionally guided by changes in the blood glucose levels and blood gases, whereas beta-hydroxybutyrate (beta-OHB)--the main ketoacid causing acidosis--is rarely measured. The purpose of this study was to evaluate if bedside monitoring of blood beta-OHB levels can simplify management of DKA through elimination of superfluous laboratory monitoring.
  
  
  METHODS
  Our emergency department treated 68 children with DKA using a standard protocol with monitoring of venous pH, partial pressure of CO(2) (pCO(2)), bicarbonate, glucose, blood urea nitrogen, and electrolytes (two to 10 time points per patient). Venous beta-OHB levels were measured using the Precision Xtra meter (MediSense/Abbott Diabetes Care, Abbott Park, IL) and, on duplicate batched serum samples, using a reference laboratory method (Cobas Mira Plus; Roche Diagnostics, Indianapolis, IN). Correlations between bedside meter beta-OHB and other parameters were evaluated in a series of general linear models with a time series covariance structure fit using spatial power law.
  
  
  RESULTS
  The bedside meter beta-OHB levels were significantly correlated with pH (r = -0.63; P <0.0001), bicarbonate (r = -0.74; P <0.0001), and pCO(2) (r = -0.55; P <0.0001) at all points of measurement during the treatment (unadjusted Pearson correlations). The pH, bicarbonate, and pCO(2) were entered into separate time series analysis models with treatment duration as a measure of time. The results confirmed that bedside levels of beta-OHB correlated very closely with time-dependent levels of venous pH, bicarbonate, and pCO(2). Good agreement between the two methods of beta-OHB measurement (r = 0.92; P <0.0001) was confirmed using the Bland-Altman plot analysis.
  
  
  CONCLUSIONS
  The Precision Xtra accurately measures blood beta-OHB levels, particularly at lower levels. While the initial measurement of pH and/or bicarbonates is warranted, real-time beta-OHB levels may replace repeat laboratory measurement of these parameters in the management of DKA. Future studies should evaluate safety and cost-effectiveness of such simplified DKA treatment protocol.
authors.affiliation: Pediatric Emergency Medicine, Department of Pediatrics, University of Colorado at Denver and Health Sciences Center, Denver, Colorado 80218, USA. rewers.arleta@tchden.org
authors.forename: Arleta
authors.initials: A
authors.lastname: Rewers
authors.forename: Kim
authors.initials: K
authors.lastname: McFann
authors.forename: H Peter
authors.initials: HP
authors.lastname: Chase
mesh_terms: D020155:3-Hydroxybutyric Acid / Q000097:blood*; D000293:Adolescent; D002648:Child; D016883:Diabetic Ketoacidosis / Q000097:blood*; D004563:Electrochemistry / Q000295:instrumentation; D005260:Female; D006801:Humans; D008297:Male; D019095:Point-of-Care Systems / Q000592:standards*
chemical_list: D020155:3-Hydroxybutyric Acid