Lecture Notes: AGS and Acid-Base Imbalances

Introduction

• Speaker: Nurse Mike from SimpleNursing.com
• Topics Covered: Acid-Base Imbalances and AGS
• Content: Overview, pathophysiology, memory tricks, practice questions

Basics of Acid-Base Imbalances

• Definition: Balance of acid and base in the body, measured via blood pH
• Normal pH Range: 7.35 to 7.45
  • Below 7.35: Acidosis (too much acid)
  • Above 7.45: Alkalosis (too much base)
• Key Players:
  • HCO3 (Bicarbonate): Base, associated with alkalosis
  • CO2 (Carbon dioxide): Acid, associated with acidosis
  • Hydrogen Ions: Acidic, found in stomach acids and urine

Organ Systems Involved

• Lungs:
  • Control CO2 levels
  • Respiratory Rate Impact:
    • Low rate: More CO2 retained, more acidic
    • High rate: Less CO2, more alkaline
• Kidneys:
  • Control hydrogen ions and bicarbonate
  • Function:
    • Excrete acid, retain base
    • Compensate by adjusting acid/base levels

Compensation

• Definition: Body adjusts acid/base levels to maintain balance
• Mechanism:
  • Lungs and kidneys work together
  • Changes in respiratory rate or acid/base excretion

Types of Imbalances

• Metabolic Alkalosis:
  • Loss of stomach acid (e.g., vomiting, NG tube suctioning)
  • Memory Trick: Think "ulosis" like vomiting
• Metabolic Acidosis:
  • Causes: Diarrhea, renal failure, DKA
  • Memory Tricks:
    • Diarrhea: "Pooping out your base"
    • Renal Failure: "If kidneys fail, acid prevails"
• Respiratory Acidosis:
  • Low/slow breathing (e.g., sleep apnea, head trauma)
  • Memory Trick: "Snoring acidosis"
• Respiratory Alkalosis:
  • Fast breathing (e.g., hyperventilation, anxiety)
  • Memory Trick: "Panting like a dog"

Practice Questions and Tips

• Common Exam Questions:
  • Causes of respiratory acidosis: Low respiratory rate
  • Causes of respiratory alkalosis: Hyperventilation
• Diagnostic Tests:
  • Arterial Blood Gases (ABGs): For assessing oxygenation, ventilation
  • Allen's Test: Ensures artery patency before drawing blood

Analyzing ABGs

• Method: Marching Band Suit Method
• Steps:
  1. Identify pH as acid or base
  2. Match pH with CO2 or HCO3
  3. Determine compensation (uncompensated, partially compensated, fully compensated)
• Practice Questions: Use structured approach for analysis (e.g., pH matching, compensation)

Conclusion

• Recap Memory Tricks:
  • Alkalosis: "Vomiting alosis"
  • Acidosis: "Pooping acidosis"
• Key Points:
  • Importance of understanding compensation
  • Using structured methods for ABG analysis

Additional Resources

• Study Guides: Available for Simple Nursing members
• Videos and Practice Questions: Access via Simple Nursing membership
• Encouragement: Utilize memory tricks and structured methods for success in exams