Normal ABG Values and Ranges

• • co2 is an acid
  • o2 is neutral - does not influence pH
  • HCO3 is an alkaline
  • Base Excess (BE) is a calculated measure of change in HCO3 levels
• Normal ABG Values and Ranges - pH

  • pH 7.35 - 7.45 (Mean 7.4)
  • A value below 7.35 is acid
  • A value above 7.45 is alkali
  • EVEN WHEN IN NORMAL RANGE
• Normal ABG Values and Ranges - PaCO2

  • PaCO2 4.5 - 6 kPa
  • CO2 is an acid therefore:
  • A value above 6 kPa is acid
  • A value below 4.5 kPa is alkali
• Normal ABG Values and Ranges - PaO2

  • PaO2 11 - 14 kPa (neutral so no effect on acid-base balance)
• Normal ABG Values and Ranges - HCO3

  • HCO3 - 22 - 26 mmol/l
  • HCO3 - is an alkali therefore:
  • A value above 26 mmol/l is alkali
  • A value below 22 mmol/l is acid
• Normal ABG Values and Ranges - Base Excess

  • BE - 2 to + 2 (calculated value so no effect on acid-base balance)