ABG

1. ABG

2. ABG
• Blood gas analysis, also called arterial blood gas(ABG) analysis, is a
test which measures the amount of oxygen(O2) and carbon-
dioxide(CO2), as well as the acidity of the blood.

3. • Arterial blood gas is drawn from artery, brachial, femoral(invasive
procedure).
• Caution must be taken with patients on anticoagulants.
• This analysis is and essential part of diagnosis and managing the
patients oxygenation status, ventilation failure and acid base balance.

4. OXYGENATION
• PaO2 < 80mmhg = hypoxemia
• SaO2 < 93% = hypoxia
pH
• Optimal blood pH is 7.40
• Body tolerates a narrow margin of normal pH of 7.35 – 7.45
• Acidosis = 7.35( )
• Alkalosis = 7.45( )

5. PaCO2
• < 35 indicates respiratory alkalosis
• > 45 indicates respiratory acidosis
HCO3
• < 22 indicates metabolic acidosis
• > 26 indicates metabolic alkalosis

6. Metabolic acidosis [H+] PH HCO3 pCO2
Metabolic alkalosis [H+] PH HCO3 pCO2
Respiratory acidosis [H+] PH pCO2 HCO3
Respiratory alkalosis [H+] PH pCO2 HCO3
DISORDER PRIMARY RESPONSE COMPENSATORY
RESPONSE

7. COMPENSATORY MECHANISM
• If the problem is respiratory in origin, kidney will work to correct it
• If the problem is metabolic in origin, lung will work to correct it

8. DEGREE OF COMPENSATION
• Uncompensated (if pH abnormal, and one other abnormal)
• Partially compensated (all 3 abnormal)
• Fully compensated (pH normal, but others both abnormal)

9. THANK YOU