Quick Take: CPAP = one pressure. BiPAP = two pressures (IPAP/EPAP). Use NIPPV early to improve oxygenation and ventilation and reduce intubation.
What It Is
- NIPPV = Non-Invasive Positive Pressure Ventilation (mask interface).
- CPAP: single continuous pressure (like PEEP) to recruit alveoli and improve oxygenation.
- BiPAP: two pressures — IPAP assists ventilation (CO₂ offload); EPAP keeps alveoli open (oxygenation).
When to Use / Not Use
Indications (typical)
- Awake, protecting airway, usually ≥12 yrs.
- Resp distress with ≥2: RR > 22, SpO₂ < 94% on O₂, accessory muscle use, speaking in short phrases.
- Hypoxemia (e.g., cardiogenic pulmonary edema/CHF).
- Hypercapnia (e.g., COPD exacerbation; consider BiPAP).
Contraindications
- Respiratory or cardiac arrest; severe AMS; cannot protect airway.
- Active vomiting, upper GI bleed, facial trauma preventing seal.
- Severe hypotension; untreated pneumothorax (barotrauma risk).
Initial Settings (Know These)
| Mode | Start | Goal |
|---|
| CPAP | 5 cmH₂O | Recruit alveoli, improve SpO₂, reduce work of breathing. |
| BiPAP | IPAP 10 / EPAP 5 cmH₂O | IPAP = ventilation (↓CO₂); EPAP = oxygenation (↑SpO₂). |
Titrate by Problem
Hypoxemia (e.g., Pulmonary Edema)
- Increase IPAP and EPAP together to maintain gradient.
- Physiology: ↑EPAP recruits alveoli, decreases shunt, reduces preload/afterload.
Hypercapnia (e.g., COPD)
- Widen the gradient: keep EPAP low (e.g., 5), raise IPAP gradually (e.g., 12–15).
- Physiology: larger IPAP–EPAP difference = better CO₂ offload.
Common Pitfalls & Risks
- Poor mask seal: facial hair/trauma; reposition, use different mask size, two-hand technique.
- Intolerance/anxiety: coach breathing; if protocol allows consider agent that preserves airway reflexes.
- Complications: aspiration (stop NIPPV if vomiting), hypotension, barotrauma/untreated pneumothorax, skin breakdown.
NREMT Study Hits
- Know contraindications cold (vomiting, arrest, no airway protection).
- Recall starting settings (CPAP 5; BiPAP 10/5) and how to titrate for O₂ vs CO₂ problems.
- Understand why: CPAP improves oxygenation; BiPAP adds ventilatory support for hypercapnia.
- Pair NIPPV with protocol adjuncts: pulmonary edema → consider nitro per protocol; obstructive disease → bronchodilators/steroids.
CPAP = one pressure BiPAP = IPAP/EPAP Hypoxemia → raise EPAP Hypercapnia → raise IPAP Stop if vomiting