The High Flow Nasal Cannula in the Emergency Department

Those of you who have adopted the strategy of Nasal Oxygen During Efforts at Securing A Tube know how powerful this technique is, and know that there is no reason not to take advantage of apneic oxygenation by applying nasal cannula oxygen during every airway management case. After observing the effect of this technique a few times, you may have shaken your head at all the unnecessary catecholamines released by you and your patients over the years as you or your trainee hunted around for cords as the saturation fell. But there’s also a small part of you that is glad to have been part of this earlier era, when intubating in the emergency department was a harrowing combination of skill, brute force, and luck. When intubating in the emergency department left providers drenched in sweat and epinephrine, hands trembling, wired and exhausted. When intubating in the emergency department felt like saving a life.


These days, with all the fancy airway tools and techniques, placing an endotracheal tube in the trachea often feels as dramatic as placing a foley in the urethra. Your hard-fought airway skills and intestinal fortitude seem wasted. You might find yourself obscuring your intern’s view by “applying cricoid pressure” just to watch him get that same panic-induced nausea you had to suffer day in day out, all those years, glidescope be damned. Intubation these days is too friggen easy. Well it’s about to get even easier.

The high flow nasal cannula is a device that has been used by neonatologists for some time, but is now making its way into adult medicine. By using special tubing, warming, and humidification, the device allows for the nasal adminstration of oxygen at upwards of sixty (60) liters per minute. This enables the delivery of 100% oxygen fraction and true positive pressure, up to around six centimeters water of PEEP. The apparatus itself has a relatively small footprint and is easier to set up than non-invasive ventilation. The oxygen hose connects to a seperate valve on the wall-mounted flowmeter, which liberates precious oxygen sources for the bag valve mask and face mask.

Being blasted with 60 liters per minute of oxygen through your nose isn’t a pleasure, but it’s much more comfortable than NIV, and of course allows the patient to talk, eat, vomit, whatever they want. Because so much water has to be added to the air, the HFNC should not be used in patients who cannot tolerate additional volume. We will see HFNC being used in the ED on many of the COPD and pneumonia patients who linger miserably on NIV, not sick enough to require ETI but not well enough to fly on simple supplemental oxygen.

But where HFNC really shines is during RSI. Put the big cannulae into your patient’s nose and let’r rip. Add a face mask or NIV or whatever your preoxygenation pleasure, then push your meds and laugh to yourself as the saturation rises during apnea. Whistle sweetly as the intern illuminates every inch of the soft palate with great determination. Hell, go see another patient and tell him to call you when he’s given up.* You remember, though, the days of the giants. When being regarded as a skilled laryngoscopist meant something. When the word airway made internists scatter like mice. When it wasn’t so easy to save a life.



*Note that hypercapnea is a consequence of apnea seperate from hypoxia. High CO2 levels are generally tolerated well, but now that we can seemingly oxygenate the apneic patient indefinitely, remember that patients with severe acidemia or intracranial insults require the expeditious establishment of ventilation as well as oxygenation.