Why Do I Elevate the Head of the Bed for Fiberoptic Intubation?

A few objections I hear a lot in relation to intubating patients in the upright or semi-upright position are:

  1. I’m not comfortable elevating the head of the bed after inducing anesthesia. 
  2. I’m concerned about hypotension and cerebral perfusion in the head-up position after the induction of anesthesia.

I think that underlying this objection is the ingrained bias that all patients must be (or at least ought to be) positioned perfectly supine for induction of anesthesia and intubation.  After all, this has been the de facto standard for decades, extending as far back as World War II. 

But ask yourself these questions:  do we intubate patients while they are lying flat on their backs because, a) it is safer to do so?  Or, b) because it is easier to do so?  Or, c) because it is customary to do so?

If the answer is (a), then we must explore what it is about securing an airway in the supine position that makes the task safer than in the upright or semi-upright position.  If the answer is (b) then we must explore what it is about the completely supine position that makes the task of securing the airway easier than in other positions (upright, semi-upright).  If the answer is (c) then we must explore why the usual and customary approach to airway management must necessarily obviate other positional approaches.

Let’s deal with (a) first.

When my colleagues tell my they don’t like the idea of elevating the head of the bed to intubate, I think they are thinking of the patient’s physiology, not anatomy.  That is, there is nothing inherently dangerous anatomically about positioning most patients in a more upright position prior to intubation, if such a position is not contra-indicated.  Indeed, the use of table “ramps” to elevate the torso of obese patients has become commonplace practice.  And if we are concerned about regurgitation and aspiration of gastric contents, then elevating the head of the bed is actually safer than not doing so.  All other factors being equal, there simply is not anything anatomical about the upright position that makes the task of inserting a breathing tube into an airway an unsafe venture.

Rather, I think my colleagues are voicing concern about how the patient will respond physiologically to a change in position after the administration of intubating medications.  If the patient’s physiology won’t tolerate such a position change, then of course we shouldn’t do this  But for the vast majority of patients, elevating the head of the bed after induction of anesthesia ought to be perfectly safe.  If hypotension is a concern, then consider pretreating the patient with a fluid bolus or a vasopressor.  Also, turn the monitor so that you can see it as you approach the patient from the front.  Cycle the blood pressure cuff rapidly.  And for goodness sake, get good at endoscopic intubation.  It should only take seconds.  This is a perfectly safe approach to airway management.

Now onto (b).

It is not clear to me how an operator could assert that a supine intubating position is easier than a semi-upright one having not attempted the latter to the point of proficiency.  In the supine position, the neck is not naturally extended, the tongue is falling back against the posterior pharyngeal wall and the jaw must be moved not only anteriorly, but upwardly, towards the ceiling.  The physical truth is that as the patient is positioned more and more upright, the gravity vector is aligned against you less and less..

Further, even with the patient positioned perfectly supine, it can be very difficult to intubate from the head of the bed.  Many hospital rooms and beds make it awkward and cumbersome to clamber to the head of the bed and position the patient and oneself ideally.  I like to teach paramedics how to intubate with a rigid laryngoscope while facing the patient because in many pre-hospital situations this will be the best option available to them.

Bottom line—there is nothing about the supine position that makes the task of intubation significantly easier.  

Finally (c).

I think this is the heart of the objection.  The simple truth is that we intubate with the patient in the perfectly supine position because this is how we were taught by our professors.  And this is how our professors were taught by their professors, and so forth.  We have been taught an approach to airway management that has become much more than a paradigm.   It has become dogma.  But I challenge you to find a statement in a textbook that all patients must be positioned perfectly supine for intubation.  (And while you are perusing, please find a statement that all patients must be intubated from the head of the bed.)  These statements don’t exist because the dogma (read, bias) doesn’t hold up to scrutiny. 

In many, many areas of life, the usual and customary ways of doing things are often revealed to be inferior to new and improved ways.  The same is true in airway management.  Do yourself and your patients a favor—elevate the head of the bed for intubation.  It’s safer.  It’s easier.  And it’s not dogmatic.