Question: Does HFNC reduce the need for reintubation in patients at low risk of post-extubation respiratory failure?
Study Type: Multicenter, randomized clinical trial in 7 ICUs in Spain
Study Population: Patients who passed an SBT after at least 12 hrs of mechanical ventilation were eligible if they meet the following inclusion criteria: Age <65, not initially intubated for CHF, absence of mod-severe COPD, APACHE II <12, BMI <30, no known airway problems and low risk of developing laryngeal edema, adequate cough and requiring suctioning <2xs Q8hrs, not difficult to wean, mechanical ventilation <7 days, <2 co-morbidities. Patients were excluded if they had a tracheostomy or had evidence of hypercapnia during an SBT.
Study Groups: Patients in the intervention arm were placed on HFNC with flow set at 10L/min which was titrated up at 5L/min intervals until pts experienced discomfort. FIO2 was titrated to keep SpO2 > 92%. Patients in the control arm had conventional oxygen applied through a facemask or nasal cannula titrated to keep SpO2>92% for 24 hrs.
Primary Outcome: Need for reintubation at 72 hrs.
Results: 527 patients randomized. Notable patient characteristics: primary neurologic diagnosis (29%), scheduled or urgent surgery at admission (47%), primary respiratory failure (17%). HFNC significantly reduced the need for reintubation at 72 hours (4.9% vs 12.2%, p=0.004) with a number needed to treat to prevent one reintubation of 14. Patients treated with HFNC also had lower rates of reintubation secondary to respiratory causes (8.3% vs 14.4%, p=0.03). There was no difference in ICU length of stay or mortality.
Caveats: Primarily neurology or surgery patients (not a typical MICU population), most common cause for reintubation in the control arm was inability to clear secretions which is perhaps a function of having so many pts with neurologic injuries.
Take-home Point: In a cohort of mostly surgical and neurologic patients at low risk for reintubation, HFNC reduced the need for reintubation compared to conventional oxygen therapy. It is unclear if these results are generalizable to a more typical MICU population.