title: Hydroxybutyrate near-patient testing to evaluate a new end-point for intravenous insulin therapy in the treatment of diabetic ketoacidosis in children.
abstract: BACKGROUND
  The aim of this study was to assess the clinical application of a near-patient testing (NPT) device for capillary blood hydroxybutyrate (HOB) measurement in evaluating a new end-point for intravenous insulin therapy in the treatment of diabetic ketoacidosis (DKA) in children.
  
  
  METHODS
  Children fulfilling the criteria for DKA were treated according to an integrated care pathway (ICP) with fluid replacement and insulin infusion. We measured capillary HOB hourly by NPT (Abbott Optium meter, analytical range 0-6.0 mmol/L), venous blood gases 4 hourly, and venous HOB 4 hourly by laboratory enzymatic method and tested all urine passed for ketones. Two possible ICP end-points were compared: A, pH > 7.3 followed by two successive NPT HOB measurements <1 mmol/L, and B, pH > 7.3 and urine ketone free (our current end-point).
  
  
  RESULTS
  In 35 patient episodes, the ICP was completed (28 to negative ketonuria) without significant variation. Before treatment, median (range) laboratory HOB was 9.5 mmol/L (4.6-15.70 mmol/L), pH 7.18 (6.98-7.38), and standard bicarbonate 11.5 mmol/L (4.3-18.6 mmol/L). ICP end-point A was reached after 17 h (4-39 h), whereas end-point B was not reached until 28 h (14-64 h) after starting treatment. The median lag was 11 h (1-36 h). For 59 paired venous samples (excluding samples with laboratory HOB >6 mmol/L), the relation between NPT (y) and laboratory (x) HOB was y = 0.92x - 0.05, r(2)= 0.94, mean bias -0.25 mmol/L.
  
  
  CONCLUSIONS
  (i) Serial measurement of NPT HOB allows evaluation of a new, simple, earlier end-point for intravenous insulin therapy. (ii) Agreement between NPT and laboratory HOB was clinically acceptable for HOB levels within the meter's analytical range.
authors.affiliation: Department of Diabetes, Royal Hospital for Sick Children, Edinburgh, UK. kathryn.noyes@luht.scot.nhs.uk
authors.forename: Kathryn J
authors.initials: KJ
authors.lastname: Noyes
authors.forename: Patricia
authors.initials: P
authors.lastname: Crofton
authors.forename: Louise E
authors.initials: LE
authors.lastname: Bath
authors.forename: Angela
authors.initials: A
authors.lastname: Holmes
authors.forename: Lesley
authors.initials: L
authors.lastname: Stark
authors.forename: Craig D
authors.initials: CD
authors.lastname: Oxley
authors.forename: Christopher J H
authors.initials: CJ
authors.lastname: Kelnar
mesh_terms: D020155:3-Hydroxybutyric Acid / Q000097:blood*; D000293:Adolescent; D015415:Biomarkers / Q000097:blood; D002648:Child; D002675:Child, Preschool; D016883:Diabetic Ketoacidosis / Q000097:blood* / Q000188:drug therapy*; D004784:Environmental Monitoring / Q000379:methods; D005260:Female; D006801:Humans; D006863:Hydrogen-Ion Concentration; D007004:Hypoglycemic Agents / Q000008:administration & dosage / Q000627:therapeutic use; D007223:Infant; D007262:Infusions, Intravenous; D007328:Insulin / Q000008:administration & dosage / Q000627:therapeutic use*; D007657:Ketone Bodies / Q000097:blood; D008297:Male
chemical_list: D015415:Biomarkers; D007004:Hypoglycemic Agents; D007328:Insulin; D007657:Ketone Bodies; D020155:3-Hydroxybutyric Acid