|There was an old fellow named Green, Who grew so abnormally lean, And flat, and compressed, That his back touched his chest, And sideways he couldn't be seen. There was a young lady of Lynn, Who was so excessively th... Read more of THIN PEOPLE at Free Jokes.ca|| Informational|
Medical ArticlesIs Physical Culture Good For Girls?
A NUMBER of women were watching a game of basket-ball...
Pain is often felt in parts of the back or sides which will yi...
5. Cardiac Emergency Drugs.--Besides some of the drugs alread...
Remedy Finding A
It will sometimes occur, in the case of those endeavouring to ...
Affection Of The Cerebellum And Spine
In affections of the _cerebellum_ and _spinal marrow_, the pa...
Punctures Case Ii
Mrs. Middleton, aged 40, wounded her wrist, on the ulnar side...
Giddiness And Trembling
This comes very often as the result of loss of nerve power in ...
The points to be gained are, to reduce the action of the amat...
The Triviality Of Trivialities
LIFE is clearer, happier, and easier for us as things assume ...
acts favorably on cancers, and is a specific when applied to ...
Treatment Of Cicatricial Stenosis
A careful direct endoscopic examination is essential before ...
Part of a raw turnip is grated down to a pulp. As much of this...
Length Of Pack Perspiration
To make quite sure of the reaction, the single sheet may be t...
Site Of Lodgement
Almost all foreign bodies are arrested in the cervical esoph...
Why We Cook our Food. While some of all classes of food may...
See Band, Flannel. ...
For an ordinary convulsive attack in the case of a child, hold...
Rules For Direct Laryngoscopy
1. The laryngoscope must always be held in the left hand, nev...
The Popularity of Beverages. For some curious reason, the h...
Often inflammation occurs in the centre of, or beneath, a mass...
Dimensions Of The Trachea And Bronchi
Category: ANATOMY OF LARYNX, TRACHEA, BRONCHI AND ESOPHAGUS, ENDOSCOPICALLY CONSIDERED
Source: A Manual Of Peroral Endoscopy And Laryngeal Surgery
It will be noted that the
bronchi divide monopodially, not dichotomously. While the lumina of
the individual bronchi diminish as the bronchi divide, the sum of the
areas shows a progressive increase in total tubular area of
cross-section. Thus, the sum of the areas of cross-section of the two
main bronchi, right and left, is greater than the area of cross
section of the trachea. This follows the well known dynamic law. The
relative increase in surface as the tubes branch and diminish in size
increases the friction of the passing air, so that an actual increase
in area of cross section is necessary, to avoid increasing resistance
to the passage of air.
The cadaveric dimensions of the tracheobronchial tree may be
epitomized approximately as follows:
Male Female Child Infant
Diameter trachea, 14 X 20 12 X 16 8 X 10 6 X 7
Length trachea, cm. 12.0 10.0 6.0 4.0
Length right bronchus 2.5 2.5 2.0 1.5
Length left bronchus 5.0 5.0 3.0 2.5
Length upper teeth to trachea 15.0 23.0 10.0 9.0
Length total to secondary bronchus 32.0 28.0 19.0 15.0
In considering the foregoing table it is to be remembered that in life
muscle tonus varies the lumen and on the whole renders it smaller. In
the selection of tubes it must be remembered that the full diameter of
the trachea is not available on account of the glottic aperture which
in the adult is a triangle measuring approximately 12 X 22 X 22 mm.
and permitting the passage of a tube not over 10 mm. in diameter
without risk of injury. Furthermore a tube which filled the trachea
would be too large to enter either main bronchus.
The normal movements of the trachea and bronchi are respiratory,
pulsatory, bechic, and deglutitory. The two former are rhythmic while
the two latter are intermittently noted during bronchoscopy. It is
readily observed that the bronchi elongate and expand during
inspiration while during expiration they shorten and contract. The
bronchoscopist must learn to work in spite of the fact that the
bronchi dilate, contract, elongate, shorten, kink, and are dinged and
pushed this way and that. It is this resiliency and movability that
make bronchoscopy possible. The inspiratory enlargement of lumen opens
up the forceps spaces, and the facile bronchoscopist avails himself of
the opportunity to seize the foreign body.
Next: The Esophagus
Previous: Anatomy Of Larynx Trachea Bronchi And Esophagus Endoscopically Considered