Home › Cheat Sheets › Physiological Adaptation

Arterial Blood Gas Interpretation — NCLEX Cheat Sheet

pH 7.35-7.45 normal

🔖 Save

👤 By the CinnaRN Clinical Content Team 🕐 Updated 2026-07-11 🏷️ Physiological Adaptation 🔖 Free to read, print, and share

💡

Use this quick-reference guide to spot, treat, and prevent Arterial Blood Gas Interpretation on the NCLEX. Keep it handy during review and on exam day!

🩺

🧪

Values

Key numbers

pH 7.35-7.45
PaCO2 35-45 mmHg (lungs)
HCO3 22-26 mEq/L (kidneys)

📌

Rome

Key facts

Respiratory Opposite: pH↑ CO2↓
Metabolic Equal: pH↑ HCO3↑

📌

Acid

Key facts

pH <7.35 = acidosis
Resp acid: ↑CO2 (hypovent, COPD)
Metab acid: DKA, diarrhea, renal

📌

Alk

Key facts

pH >7.45 = alkalosis
Resp alk: hyperventilation/anxiety
Metab alk: vomiting, antacids

✨

Quick Tip

Normal pH is 7.35-7.45; below 7.35 is acidosis, above 7.45 is alkalosis.

📖 Related Topics

Hypokalemia Hyperkalemia Hyponatremia Heart Failure

Was this helpful? ✎ Suggest an edit

Master Arterial Blood Gas Interpretation with practice, not just reading

4,700+ NCLEX-style questions with rationales, 51 interactive NGN cases, and an AI tutor — free every day, no card needed.

Practice Physiological Adaptation questions free →

Related Physiological Adaptation cheat sheets

HypokalemiaK+ < 3.5 mEq/L HyperkalemiaK+ > 5.0 mEq/L HyponatremiaNa+ < 135 mEq/L Heart FailurePump fails → congestion Diabetic Ketoacidosis (DKA)Glucose > 250, pH < 7.35 HypoglycemiaGlucose < 70 mg/dL COPDChronic airflow obstruction Sepsis and Septic ShockInfection → organ failure