Does the cricothyroid membrane location really change with the extension of the head and neck from neutral position? Ultrasound opens our eyes.

Abstract

The emergency surgical approach of the airway to a situation "can’t intubate, can’t oxygenate’ is a scenario implies an adequate training on the part of the anesthesiologist that enables a successful resolution in the shortest posible time. In view of the low frequency of this practice, many anesthesiologists choose to locate the cricothyroid membrane before performing the anesthetic induction with the head and neck in a neutral position. Considering this and that the ideal position for a cricothyroidotomy is placing the head and neck in extension, the authors of this article try to determine if there is a change in the location of the membrane with the variation of the head and neck position from neutral to extended as well as if the height of the membrane is modified. To do this, hey performed an observational study with 22 healthy volunteers to whom a radiologist with more than fifteen years of experience measures with ultrasound the distance between the upper and lower membrane edges and makes a mark at the midpoint of the same in the two positions mentioned above. The results obtained from the study lead us to an important reflection that leads us to a change in the classical paradigm of approach of the cricothyroidotomy.