ABG

mainly for GNM & B.Sc nursing student ..

1. PRESENTED BY PRAGYANSHREE NANDA MEDICAL-SURGICAL NURSING PG 1 ST YR

2. PROCEDURE ON ABG INTERPRETATION

3. INTRODUCTION A blood gas test measures the amount of oxygen and carbon dioxide in the blood. It may also be used to determine the pH of the blood Analysis of arterial blood gases (ABG) is useful for patients with suspected respiratory or metabolic diseases.

4. DEFINITION Arterial blood gas (ABG): The sampling of the blood levels of oxygen and carbon dioxide within the arteries, as opposed to the levels of oxygen and carbon dioxide in venous blood. Typically the acidity, or pH, of the blood is measured simultaneously with the gas levels in  ABG

5. ARTERIAL BLOOD GAS ( ABG ) An Arterial Blood gas test measures the acidity (pH) and the level of oxygen and carbon- di -oxide in the blood from the artery . This is used to check how well the lungs are able to move oxygen into the blood and remove carbon- di -oxide from the blood.

6. COMPONENTS OF BLOOD GAS Oxygen- pao 2 , sao 2, ventilator- pco 2 acid-base- pH, HCO 3 – BE

7. COMMON TERMS PCO 2 (ventilation): partial carbon di oxide PaO 2 (Oxygenation): partial Oxygen HCO 3 (metabolism): Bicarbonate O 2 sat : Oxygen saturation pH : Acid-base balance BE : Base excess

8. Indications Respiratory failure Cardiac failure. Liver failure. Renal failure. Hyperglycaemic . Multiorgan failure. Sepsis. Burns. Poisons/toxins . Ventilated patients. Sleep studies. Severely unwell patients from any cause affects prognosis.

9. NORMAL ABG PARAMETER NORMAL VALUE pH 7.35-7.45 PaCO 2 35-45 mg/dl PO 2 70-100 mg/dl SaO 2 ≥ 93% HCO 3 22-26 mEq/l BE -2 to +2 mEq/l

10. TARGET BLOOD GAS IN NEONATE Parameters < 28 weeks gestation 28-40 weeks gestation Term with PPHN Infant with BPD pH ≥7.25 ≥7.25 7.30-7.50 7.35-7.45 Paco 2 45-55 45-55 30-40 55-65 Pao 2 45-65 50-70 80-120 50-80

11. 6 STEPS TO ABG ANALYSIS Is the pH normal? Is the co2 normal? Is the HCO3 normal? Match the co2 or HCO3 with the pH Does the co2 or HCO3 go the opposite direction? Are the pO2 and O2 sat. normal?

12. WHAT MAY GO WRONG IN ABG HYPOXIA : ↓ PaO 2 ↓ O 2 saturation Causes: RDS , pneumonia, cyanotic heart disease, CHF, abnormal hemoglobin

13. CONT... ACID-BASE DISORDERS: Primary acid base disorder Respiratory acidosis Respiratory alkalosis Metabolic acidosis Metabolic alkalosis Compensation Mixed acid base disorder

14. PRIMARY ACID BASE DISORDER ROME R: RESPIRATORY O: OPPOSITE M: METABOLIC E: EQUAL

15. CONT... Primary acid base disorder: pH PaCO 2 HCO 3 Respiratory acidosis ↓ ↑ Normal Respiratory alkalosis ↑ ↓ Normal Metabolic acidosis ↓ Normal ↓ Metabolic alkalosis ↑ Normal ↑

16. PARTIALLY COMPENSATED ACID- BASE DISORDERS pH PaCO 2 HCO 3 Respiratory acidosis ↓ ↑ ↑ Respiratory alkalosis ↑ ↓ ↓ Metabolic acidosis ↓ ↓ ↓ Metabolic alkalosis ↑ ↑ ↑

17. COMPLICATIONS Hematoma Thrombosis and embolism Infection Inaccurate blood gas result Excessive heparin may result in a false pH and paco2 Air bubbles may falsely elevate the pao2 and falsely lower the paco2

18. SUMMARY

19. Quick quiz - 1 A 17-year-old patient presents to A&E complaining of a tight feeling in their chest, shortness of breath, some tingling in their fingers and around their mouth. An ABG is performed on the patient whilst they’re breathing room air and the results are shown below … pH= 7.8, Pco2 = 34mg/dl , po2=70mg/dl , HCO3 = 29 mEq /l Interprete above blood gas a. Metabolic acidosis b. Respiratory acidosis c. Metabolic alkalosis d. Respiratory alkalosis

20. Quick quiz - 2 A 6 days term baby admitted in NICU with severe respiratory distress syndrome. ABG report: pH= 7.20, Paco2= 25mg/dl, pao2=70mg/dl, HCO3 = 20 mEq/l. Interprete above blood gas. a. Metabolic acidosis b. Respiratory acidosis c. Partially compensated metabolic acidosis d. Partially compensated respiratory acidosis

21. conclusion