Acute Respiratory Failure — NCLEX Cheat Sheet
PaO2 <60 or PaCO2 >50Also known as: respiratory failure · ARF · lungs failing · respiratory arrest
Use this quick-reference guide to spot, treat, and prevent Acute Respiratory Failure on the NCLEX. Keep it handy during review and on exam day!
🩺📒 The 1-minute cheat sheet
🧪 Labs
- PaO2 <60 mmHg = hypoxemic
- PaCO2 >50 + pH <7.35 = hypercapnic
- ABG = key diagnostic
🩺 Signs
- Restless, confusion = early hypoxia
- Accessory muscles, retractions
- Cyanosis, ↓ LOC = late/severe
✅ Do
- ↑ HOB, O2 to titrate SpO2
- Prep intubation/mechanical vent
- Treat underlying cause
📌 Avoid
- High O2 in COPD → ↓ resp drive
- Sedatives → worsen hypoventilation
📚 Acute Respiratory Failure — full study notes
The cheat sheet above is your quick recall card. These notes go deeper — what it is, what to do first, what must be reported, and what to teach.
Key points
Understand these first- Hypoxemic failure (type 1) shows PaO2 below 60; hypercapnic failure (type 2) shows PaCO2 above 50 with pH below 7.35.
- Early signs are restlessness, anxiety, confusion, and tachycardia from hypoxia.
- Dyspnea, tachypnea, accessory muscle use, and nasal flaring reflect increased work of breathing.
- Late signs include cyanosis, decreased level of consciousness, bradycardia, and a falling respiratory rate.
- Headache, drowsiness, and flushed skin suggest carbon dioxide retention.
- A decreasing respiratory rate with worsening hypoxia signals fatigue and impending arrest, not improvement.
Nursing priorities
What to do, in order- Apply oxygen and position the patient upright to maximize ventilation.
- Maintain a patent airway and prepare for noninvasive ventilation or intubation if needed.
- Call the rapid response team and obtain ABGs to guide management.
- Treat the underlying cause, such as a bronchodilator for bronchospasm or antibiotics for infection.
- Continuously monitor oxygenation, ventilation, level of consciousness, and cardiac rhythm.
Red flags — report now
Escalate immediately- A falling respiratory rate, rising CO2, and decreasing level of consciousness indicate impending respiratory arrest.
- Cyanosis, bradycardia, and unresponsiveness require immediate airway intervention.
- In a COPD patient, high-flow oxygen can suppress the hypoxic drive, so titrate to the lowest effective level and watch for rising CO2.
Labs & values
Numbers to know- Type 1 (hypoxemic): PaO2 <60 mmHg (normal 80-100)
- Type 2 (hypercapnic): PaCO2 >50 mmHg (normal 35-45) with pH <7.35
- Monitor SpO2 (normal 95-100%) and serial ABGs
❓ Acute Respiratory Failure: NCLEX FAQs
What are the priority nursing interventions for Acute Respiratory Failure?
Apply oxygen and position the patient upright to maximize ventilation. Maintain a patent airway and prepare for noninvasive ventilation or intubation if needed. Call the rapid response team and obtain ABGs to guide management. Treat the underlying cause, such as a bronchodilator for bronchospasm or antibiotics for infection.
What are the warning signs of Acute Respiratory Failure a nurse must report?
A falling respiratory rate, rising CO2, and decreasing level of consciousness indicate impending respiratory arrest. Cyanosis, bradycardia, and unresponsiveness require immediate airway intervention. In a COPD patient, high-flow oxygen can suppress the hypoxic drive, so titrate to the lowest effective level and watch for rising CO2.
What do I need to know about Acute Respiratory Failure for the NCLEX?
Hypoxemic failure (type 1) shows PaO2 below 60; hypercapnic failure (type 2) shows PaCO2 above 50 with pH below 7.35. Early signs are restlessness, anxiety, confusion, and tachycardia from hypoxia. Dyspnea, tachypnea, accessory muscle use, and nasal flaring reflect increased work of breathing. Late signs include cyanosis, decreased level of consciousness, bradycardia, and a falling respiratory rate.
What lab values are associated with Acute Respiratory Failure?
Type 1 (hypoxemic): PaO2 <60 mmHg (normal 80-100). Type 2 (hypercapnic): PaCO2 >50 mmHg (normal 35-45) with pH <7.35. Monitor SpO2 (normal 95-100%) and serial ABGs.
Quick Tip
Hypoxemic failure (type 1) shows PaO2 below 60; hypercapnic failure (type 2) shows PaCO2 above 50 with pH below 7.35.
📖 Related Topics
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