Solving Arterial Blood Gas (ABG) Problems with Tic-Tac-Toe and Row Method

Jun 30, 2024

Review flashcards

Solving Arterial Blood Gas (ABG) Problems with Tic-Tac-Toe and Row Method

Key Concepts

  • ABG Problems: Looking for acid/base imbalance
  • Three Values Given: Blood pH, CO2 (carbon dioxide - respiratory), HCO3 (bicarb - metabolic)
  • **Normal Ranges: **
    • pH: 7.35-7.45 (Acidotic < 7.35, Alkalotic > 7.45)
    • CO2: 35-45 (Acidotic > 45, Alkalotic < 35)
    • HCO3: 22-26 (Acidotic < 22, Alkalotic > 26)

Steps to Solve ABG Problems

  1. Determine if the Problem is Respiratory or Metabolic
  2. Identify Acidosis or Alkalosis
  3. Check Compensation (Uncompensated, Partial, Full)

Rome Method

  • Rome Acronym:
    • R: Respiratory
    • O: Opposite
    • M: Metabolic
    • E: Equal
  • Interpretation:
    • Respiratory (CO2) Opposite pH
      • High CO2 and Low pH: Respiratory Acidosis
      • Low CO2 and High pH: Respiratory Alkalosis
    • Metabolic (HCO3) Equal pH
      • Low HCO3 and Low pH: Metabolic Acidosis
      • High HCO3 and High pH: Metabolic Alkalosis
  • Example Problems:
    • Case 1: pH = 7.28, CO2 = 50, HCO3 = 24
      • pH Low (Acidotic), CO2 High (Acidotic), HCO3 Normal
      • Opposites: Respiratory Acidosis (Uncompensated)
    • Case 2: pH = 7.30, CO2 = 40, HCO3 = 18
      • pH Low (Acidotic), CO2 Normal, HCO3 Low (Acidotic)
      • Equals: Metabolic Acidosis (Uncompensated)
    • Case 3: pH = 7.42, CO2 = 26, HCO3 = 18
      • pH Normal (Alkalotic side), CO2 Low (Alkalotic), HCO3 Low (Acidotic)
      • Opposites: Respiratory Alkalosis (Fully Compensated)
    • Case 4: pH = 7.37, CO2 = 32, HCO3 = 17
      • pH Normal (Acidotic side), CO2 Low (Alkalotic), HCO3 Low (Acidotic)
      • Equals: Metabolic Acidosis (Fully Compensated)
    • Case 5: pH = 7.51, CO2 = 47, HCO3 = 32
      • pH High (Alkalotic), CO2 High (Acidotic), HCO3 High (Alkalotic)
      • Equals: Metabolic Alkalosis (Partially Compensated)

Tic-Tac-Toe Method

  • Setup: Acid, Normal, Alkalotic columns
  • Process: Place pH, CO2, HCO3 in corresponding columns
  • Interpretation: Find tic-tac-toe for primary condition
  • Examples:
    • Case 1: pH = 7.22, CO2 = 49, HCO3 = 24
      • pH and CO2 in Acid column, HCO3 in Normal
      • Tic-Tac-Toe: Respiratory Acidosis (Uncompensated)
    • Case 2: pH = 7.22, CO2 = 49, HCO3 = 28
      • pH and CO2 in Acid, HCO3 in Alk
      • Partial compensation: Respiratory Acidosis (Partially Compensated)
    • Case 3: pH = 7.42, CO2 = 32, HCO3 = 18
      • pH Normal (Alkalotic side), CO2 in Alk, HCO3 in Acid
      • Full compensation: Respiratory Alkalosis (Fully Compensated)
    • Case 4: pH = 7.37, CO2 = 33, HCO3 = 17
      • pH Normal (Acidotic side), CO2 in Alk, HCO3 in Acid
      • Full compensation: Metabolic Acidosis (Fully Compensated)
    • Case 5: pH = 7.27, CO2 = 33, HCO3 = 17
      • pH, CO2, HCO3 in Acid
      • Partial compensation: Metabolic Acidosis (Partially Compensated)

Conclusion

  • Practice: Important to practice both methods
  • Resources: Quiz available via YouTube description for further practice.