Why ABG interpretation feels like decoding secret language — and how to simplify it.

02:30 – Foundations of Acid-Base Balance

CO₂ = acid (lungs control it)

Bicarb = base (kidneys control it)

The body maintains balance (homeostasis) through both systems.

06:00 – Respiratory Acidosis

Cause: CO₂ retention (slow, shallow breathing)

Examples: Opioid overdose, pneumonia

ABG Pattern: ↓ pH, ↑ CO₂, normal bicarb (acute)

Symptoms: Confusion, hypoventilation, drowsiness

Chronic case: COPD → compensated by high bicarb

11:30 – Respiratory Alkalosis

Cause: Blowing off too much CO₂ (hyperventilation)

Examples: Panic attack, pulmonary embolism, pregnancy

ABG Pattern: ↑ pH, ↓ CO₂, normal bicarb

Symptoms: Dizziness, tingling fingers/lips, lightheadedness

16:45 – Metabolic Acidosis

Cause: Too much acid or loss of base

Examples: DKA, renal failure

ABG Pattern: ↓ pH, ↓ bicarb, ↓ CO₂ (compensation)

Signs: Deep, rapid (Kussmaul) respirations, fruity breath, fatigue

22:15 – Metabolic Alkalosis

Cause: Loss of acid or gain of base

Examples: Prolonged vomiting, NG suctioning

ABG Pattern: ↑ pH, ↑ bicarb, ↑ CO₂ (compensation)

Symptoms: Shallow breathing, muscle cramps, EKG changes

27:00 – The Big Nursing Pearl

“You treat the patient, not the paper.”
ABG numbers mean nothing in isolation — always match them to your patient’s story and symptoms.

29:00 – Critical Thinking Challenge
How do shifts in pH affect electrolytes like potassium and calcium?
Recognize how alkalosis causes low potassium and low calcium, showing up as cramps or EKG changes.

30:00 – Wrap-Up & CTA
Visit ThinkLikeANurse.org for more NCLEX practice and weekly episodes that help you think like a nurse — not just study like one.

Have a FAQ to ask Brooke? Send an email to [email protected].