RESP MX PART II Flashcards
three primary functions of the nasal cavities?
warm inhaled air
humidify air to prevent dehydration
filter air
what produces our ability to make sounds?
vocal ligaments and vocal processes vibrating
how are bronchioles maintained in an open state?
by the same negative intrapleural pressure which keeps alveoli inflated
the walls of the trachea, bronchi, and bronchioles are made of what type of muscle? except for
smooth muscle
bronchiole going to the alveoli which has none
what happens to the respiratory system like the air passages in patients with obstructive lung diseases?
excessive smooth muscle contraction in the smaller bronchi and bronchioles
what is the pressure difference between the atmosphere and alveoli?
1 cm H2O
where is the greatest resistance to flow?
larger bronchi because there isn’t many of them
in disease conditions, which lung passages become key resistance points?
smaller bronchioles because
1) small diameters make them easier to occlude
2) high smooth muscle content makes for constriction
sympathetic innervation causes?
bronchodilation mediated by adrenergic B2 receptors
epinephrine and norepinephrine from the medulla
parasympathetic innervation causes? what drug is used to reverse this?
bronchoconstriction occurs from acetylcholine
atropine
*usually sparse but have vagal efferents
what are the potent mediators of bronchoconstriction?
histamine and reactive substance from mast cells amplified even more by local irritants
sneezing is triggered by what nerve? how does this work?
cranial nerve V to the medulla
uvula is depressed forcing airflow through nasal cavity to clear the triggering stimulus
what is blood pressure in the systemic circulation?
120/80, arterial pressure
what is blood pressure in the pulmonary circulation?
25/8, venous pressure
mean arterial blood pressure in the pulmonary circulation is _____? Pulse pressure here is _____?
15 mmHg
17 mmHg