Non Invasive Ventilation

This episode offers a structured, bedside-focused exploration of Non-Invasive Ventilation (NIV) for acute hypercapnic respiratory failure in COPD, aligned with NICE NG115 and BTS/ICS 2016 guidance. Aimed at early-career critical care nurses, it breaks the topic down into physiology, practical setup, monitoring, and escalation. Key Topics Covered Mechanisms behind acute-on-chronic hypercapnic respiratory failure in COPD. How NIV improves ventilation, reduces CO₂, and decreases work of breathing. Evidence-based indications for NIV initiation. Practical bedside steps for the first hour of therapy. How to titrate settings, troubleshoot problems, and recognise failure. Common complications and when to escalate to invasive ventilation. Case-Based Learning The episode follows Mr. Harris, a 68-year-old man with severe COPD presenting with type 2 respiratory failure. His clinical deterioration, ABG results (pH 7.25, pCO₂ 9.8 kPa), and work of breathing set the scene for understanding when and why NIV is beneficial. Physiology Essentials Listeners are guided through the impact of airway obstruction, air trapping, hyperinflation, respiratory muscle fatigue, and CO₂ narcosis. NIV's core actions—improving tidal volume with IPAP and splinting airways with EPAP—are linked directly to these mechanisms. Practical Bedside Framework Start with IPAP 12 cmH₂O / EPAP 4 cmH₂O and FiO₂ around 28%, aiming for SpO₂ 88–92%. Reassure the patient, optimise positioning, secure a comfortable mask seal, and monitor synchrony. Repeat ABG at 1 hour; look for rising pH and falling CO₂. Adjust pressures in small increments if needed while monitoring for leaks, agitation, hypotension, or gastric distension. Monitoring and Escalation Success indicators include reduced respiratory rate, improved alertness, and trending normalisation of pH. Red flags include worsening acidosis, declining consciousness, mask intolerance, or inability to maintain the airway—prompting urgent senior review. Common Complications Facial pressure sores, gastric distension, aspiration risk, anxiety, and haemodynamic compromise are highlighted with practical prevention strategies. Five Golden Rules Recognise early and initiate NIV promptly. Start simple with standard pressures and controlled oxygen. Reassess rapidly with a 1-hour ABG. Escalate quickly if failure criteria develop. Protect the patient with meticulous care and communication. Outcome After an hour of NIV, Mr. Harris' pH rises to 7.32 and pCO₂ falls to 8.2 kPa, with clear clinical improvement—illustrating the value of timely, well-managed NIV in COPD. Closing The episode reinforces the importance of physiological understanding in delivering confident, effective NIV care at the bedside.