title: Effects of temperature and time delay on arterial blood gas and electrolyte measurements.
abstract: OBJECTIVE
  To determine the changes in pH, PaO2, PaCO2 and Na, K, Cl in arterial blood samples stored at room temperature or on ice, at 0, 15, 30, 45 and 60 minutes.
  
  
  METHODS
  Arterial blood samples were collected in heparinized capillary tubes and stored at room temperature (24-26 degrees C) and on ice (0-4 degrees C). ABG and electrolytes were measured at 0, 15, 30, 45 and 60 minute intervals.
  
  
  RESULTS
  There were significant decreases in the pH, PaO2, Na, Cl and significant increases in PaCO2 and K over time in both groups. The changes were greater and faster at room temperature. The significant decrease in pH over time was not found until 30 minutes at room temperature and 45 minutes on ice. There were significant decreases in PaO2, concurrent with significant increases in PaCO2 from 15 minutes onwards in both groups. Both Na and K exhibited a significant change at 60 minutes in the room temperature group. Significant decreases of Cl over time were not found until 15 minutes at room temperature, and 30 minutes on ice.
  
  
  CONCLUSIONS
  For ABG and electrolytes analysis, the blood sample should be analyzed within 15 minutes and be stored at either room temperature or on ice.
authors: Department of Pediatrics, Queen Sirikit National Institute of Child Health, College of Medicine, Rangsit University, Bangkok, Thailand. psrisan@yahoo.com
authors: Panida
authors: P
authors: Srisan
authors: Teerasak
authors: T
authors: Udomsri
authors: Pravit
authors: P
authors: Jetanachai
authors: Sorasak
authors: S
authors: Lochindarat
authors: Wiboon
authors: W
authors: Kanjanapattanakul
mesh_terms: D001784:Blood Gas Analysis / Q000379:methods*; D001793:Blood Preservation; D001800:Blood Specimen Collection / Q000295:instrumentation / Q000379:methods*; D002245:Carbon Dioxide / Q000097:blood*; D002675:Child, Preschool; D004573:Electrolytes; D005260:Female; D006495:Heparin, Low-Molecular-Weight; D006801:Humans; D006863:Hydrogen-Ion Concentration; D007053:Ice; D008297:Male; D010100:Oxygen / Q000097:blood*; D010313:Partial Pressure; D013696:Temperature; D013997:Time Factors
chemical_list: D004573:Electrolytes; D006495:Heparin, Low-Molecular-Weight; D007053:Ice; D002245:Carbon Dioxide; D010100:Oxygen