Cricothyrotomy: the anatomical basis.

Cricothyrotomy is an important surgical technique. We studied the anatomy of the cricothyroid membrane in 13 adult fresh cadavers preserved at 45 degrees F and examined at 70 degrees F. The working dimensions of the cricothyroid membrane were measured for emergency cricothyrotomy and placement of an airway tube. The vertical measurement ranged from 8-19 mm (mean 13.69 +/- SE 0.96 mm) and the maximal width between the cricothyroid muscles ranged between 9 and 19 mm (mean 12.38 +/- SE 0.91 mm). The distance from the upper limit of the cricothyroid membrane to the vocal cord was 9.78 +/- SE 0.52 mm. Eight subjects (62%) had an artery delineated transversely across the cricothyroid membrane. Two subjects (15%) had sclerosis of the cricothyroid joint. To promote the safe use of cricothyrotomy, the anatomy of the cricothyroid membrane is defined and clinically relevant data are presented.