the point of the knife does not perforate
the posterior tracheal wall. Stab incisions are always to be avoided.
If the incision in the trachea is found to be of insufficient length,
the original incision must be found and elongated. A second incision
must not be made, for the portion of cartilage between the two
incisions will die and will almost certainly make a site of future
tracheal stenosis. The cricoid should never be cut, for stenosis is
almost sure to follow the wearing of a cannula in this position. A
Trousseau dilator should now be inserted in the tracheal incision, its
blades gently separated. With the tracheal lumen thus opened, a
cannula of proper size is introduced with absolute certainty of its
having entered the trachea. A quadruple-folded square of gauze in the
form of a pad about four inches square is moistened with mercuric
chloride solution (1:10,000) and is slit from the lower border to its
midpoint. This pad is slipped from above downward under the tape
holder of the cannula, the slit permitting the tubal part of the
cannula to reach the central part of the pad (Fig. 108), and
completely covers the wound. No attempt should be made to suture the
skin wound, for this tends to form a pocket in which lodge the
bronchial secretions that escape alongside the tube, resulting in
infection of the wound. Furthermore it renders the daily changing of
the tube much more difficult. In fact it prevents the attendant from
being certain that the tube is actually placed in the trachea.
Suturing of the skin to the trachea should never be done, for the
sutures soon tear out and often set up a perichondritis of the
tracheal cartilages, with resulting difficult decannulation.

[FIG. 105.--Schema of practical gross anatomy to be memorized for
emergency tracheotomy. The middle line is the safety line, the higher
the wider. Below, the safety line narrows to the vanishing point VP.
The upper limit of the safety line is the thyroid notch until the
trachea is bared, when the limit falls below the first tracheal ring.
In practice the two-dark danger lines are pushed back with the left
thumb and middle finger as shown in Fig. 106, thus throwing the safety
line into prominence. This is generally known as Jackson's
tracheotomic triangle.]

[FIG. 106.--Schema showing the author's method of rapid tracheotomy.
First stage. The hands are drawn ungloved for the sake of clearness.
The upper hand is the left, of which the middle fing