ften it is
buried in the wall.]

[168] [FIG. 84.-Schema illustrating the "mushroom anchor" problem of
the brass headed upholstery tack. At A the tack is shown with the head
bedded in swollen mucosa. The bronchoscopist, looking through the
bronchoscope, E, considering himself lucky to have found the point of
the tack, seizes it and starts to withdraw it, making traction as
shown by the dart in drawing B. The head of the tack catches below a
chondrial ring and rips in, tearing its way through the bronchial wall
(D) causing death by mediastinal emphysema. This accident is still
more likely to occur if, as often happens, the tack-head is lodged in
the orifice of the upper lobe bronchus, F. But if the bronchoscopist
swings the patient's head far to the opposite side and makes
axis-traction, as shown at C, the head of the tack can be drawn
through the swollen mucosa without anchoring itself in a cartilage. If
necessary, in addition, the lip of the bronchoscope can be used to
repress the angle, h, and the swollen mucosa, H. If the swollen
mucosa, H, has been replaced by fibrous tissue from many months'
sojourn of the tack, the stenosis may require dilatation with the
divulsor.]

[FIG. 85.--Problem of the upholstery tack with buried point. If pulled
upon, the imminent perforation of the mediastinum, as shown at A will
be completed, the bronchus will be torn and death will follow even if
the tack be removed, which is of doubtful possibility. The proper
method is gently to close the side curved forceps on the shank of the
tack near the head, push downward as shown by the dart, in B, until
the point emerges. Then the forceps are rotated to bring the point of
the tack away from the bronchial wall.]

[169] _Removal of Open Safety Pins from the Trachea and Bronchi_.--
Removal of a closed safety pin presents no difficulty if it is grasped
at one or the other end. A grasp in the middle produces a "toggle
and ring" action which would prevent extraction. When the
safety pin is _open with the point downward_ care must be exercised
not to override it with the bronchoscope or to push the point through
the wall. The spring or near end is to be grasped with the side-curved
or the rotation forceps (Figs. 19, 20 and 31) and pulled into the
bronchoscope, thus closing the pin. An open safety pin lodged point up
presents an entirely different and a very difficult problem. If
traction is made without closing the pin or protecting the point
sev