It is by and large a foregone conclusion that non-invasive ventilation (NIV) saves intubations (and lives) in COPD and CHF. There has not been too much #FOAM specifically for pneumonia and NIV, so let’s dive in.
Recently, there was a publication stating that NIV treatment failure was significantly higher for pneumonia vs COPD (49% vs 12%). This was a small study (under 80 patients), but does this mean we should not try NIV for pneumonia? More importantly, do pneumonia patients have worse outcomes than they otherwise would if they were intubated sooner? Is it worthwhile to give a NIV trial in pneumonia?
To start, 127 patients with respiratory failure secondary to community-acquired pneumonia (CAP) were examined prospectively. 25% of these patients failed NIV. Those that failed NIV were more likely to have confusion at presentation, were >65 years old, had worsening chest films over time, and lack of improvement at 1 hour on NIV. A second study of similar ilk (CAP placed on NIV) examined 64 patients in which 43% of patients successfully avoided intubation (ie, 57% failed NIV). Success was associated with a lower APACHE II score, higher pH at the end of NIV trial (7.34 vs 7.44), and lower respiratory rate (28 vs 23 breaths/minute).
Now that flu season is upon us, let’s examine the 685 patients with confirmed influenza A that were studied in Barcelona in a prospective observational registry. 489 patients were intubated in the ED and 177 received NIV. NIV was effective 40.6% of the time, and associated with shorter LOS. Key details in this study were that not requiring vasopressors, the absence of renal failure, and fewer than one lobe involvement on CXR were all significantly associated with successful NIV. Most importantly, the delay in intubation did not affect mortality (26.5% for ETT, 24.2% for NIV). Thus, for every 100 NIV patients in whom the decision to intubate was made, there was ~25% mortality – roughly the same rate as those that were intubated without a NIV trial – so the delay does not worsen outcomes.
For the immunocompromised, an evaluation of 120 patients came to similar conclusions: higher APACHE II scores and a need for vasopressors were associated with failure of NIV. Underlying disease did not affect NIV duration rates or outcomes. Again, the authors found that the mortality rate of failed NIV patients that required intubation was similar to those that were intubated from the start.
Conclusions? If you need to start pressors, or have new onset renal insufficiency, you may want to skip NIV and reach for the intubation kit first. Otherwise, with 40-75% success rate of NIV, and without an adverse outcome for delayed intubation in pneumonia patients, it seems reasonable for the patient to first have a trial of non-invasive ventilation.