UMEM Educational Pearls

  • When considering starting a patient on non-invasive ventilation (NIV), ask yourself whether the patient is having a problem of oxygenation (Type I respiratory failure) or a problem of CO2 removal or ventilation (i.e., Type II respiratory failure); don’t forget both types can be present, simultaneously
  • Examples of Type I problems are pneumonia and pulmonary edema; examples of Type II problems are COPD, drug overdose, and neuromuscular disease (e.g., myasthenia gravis). Once the underlying problem is identified, selecting the type of NIV is straight-forward. 
  • There are only two interventions for type I disorders: 1) increase fio2 and/or 2) increase mean airway pressure (positive end-expiratory pressure; a.k.a. PEEP). There are only two interventions for type II disorders: 1) increase tidal volume and/or 2) increase respiratory rate 
  • Continuous positive airway pressure (CPAP) only provides support for type I problems (i.e., can titrate FiO2 and PEEP); CPAP does not provide a tidal volume or a respiratory rate (needed for type II support)
  • Bi-level positive airway pressure (BPAP) provides support for type II problems; tidal volume can be titrated by increasing the pressure support and a respiratory rate can be dialed in.

Editors note: The new Back 2 Basic series will review essential critical care concepts on the first Tuesday of each month. Want a specific topic reviewed? Contact us by email or Twitter.


Follow me on Twitter (@criticalcarenow) or Google+ (+criticalcarenow)