Modern surfactant therapy emphasizes less-invasive delivery methods to avoid positive pressure barotrauma and mechanical ventilation.
Key Physiological Equations & Formulas
- Comparison of Delivery Modes: $$\text{LISA / MIST (Thin Catheter)} \quad \text{vs} \quad \text{INSURE (Intubate-Surfactant-Extubate)}$$ LISA preserves spontaneous diaphragmatic breathing throughout administration, reducing BPD and death.
Practical Clinical Pearls & Bedside Rules
- LISA Technique: Pass a small flexible 16-18G vascular catheter or feeding tube through the vocal cords under direct/video laryngoscopy while maintaining CPAP and spontaneous breathing.
- MIST Technique: Uses a semi-rigid vascular catheter (e.g., Angiocath) for easier glottic entry without Magill forceps.
Initial Settings & Clinical Titration Protocol
| Parameter | Recommended Initial Setting | Titration Goal / Safety Threshold |
|---|---|---|
| Sedation during LISA | Careful light analgesia (e.g., low-dose fentanyl or ketamine) | Maintain spontaneous respiratory drive during catheter placement. |
| CPAP Maintenance | Maintain CPAP 6-8 cmH2O throughout procedure | Prevents alveolar collapse during surfactant spreading. |
Bedside Troubleshooting & Red Flags
Warning
Catheter Dislodgement into Esophagus: Watch for surfactant reflux into pharynx and lack of oxygenation improvement. Reposition catheter with laryngoscopy.
Key Takeaways & Summary
- Always evaluate patient synchrony and physiological response before changing ventilator parameters.
- Maintain lung-protective strategies to minimize driving pressure ($\Delta P$) and mechanical power.
- Continuously reassess liberation and extubation readiness on daily morning rounds.