CMD - HypO2xia Flashcards
During hypoxia, systemic arterioles dilate by opening your _____ channels due to hypoxia induced reduction in ATP concentration
K-ATP channels
True of effects of hypoxia on CNS EXCEPT
a. affects the higher center
b. hypoxia causes impaired judgment, motor incoordinaton, resembling acute alcoholic intoxication
c. Cause of death from high altitude cerebral edema is primarily cardiac
d. Pulmonary arterial
and venous constriction causes capillary leakage and high altitude pulmonary edema
(HAPE), intensifies hypoxia furthering the promotion of vasoconstriction
C; primarily respiratory
True of effects of hypoxia to cardiovascular system
a. increase in myocardial contractility
b. depressed myocardial contractility
c. both
d. neither
C; transiently increase myocardial contracility, later on depressed
When hypoxia occurs during respiratory faliure, the following statements are true EXCEPT
a. PaO2 declines and hemoglobin dissociation curve is displaced to the left
b. greater O2 is released in tissue
c. arterial hypoxemia present with cyanosis
d. NOTA
A; shift to the right
most common cause of hypoxia
V/Q mismatch resulting from poorly ventilated alveoli
direction of intrapulmonary shunting resulting to perfusion of nonventilated portions of the lung
intrapulmonary right to left shunting
Itrapulmonary right to left shunting can be observed in these 2 conditions
pulmonary atelectasis
pulmonary arteriovenous connections
Hypoxia secondary to high altitude ascends rapidly to ______m
3,000
High altitude illness develop at an elevation of _____
3,000 ft; asscends rapidly
reduction of oxygen content of inspired air in high altitude illness leads to
decrease alveolar PO2
level of PO2 in high altitude illness
60mmHg below
at this altitude, normal function of arterial saturation ceases due to changes of CNS function
5,000m
this condition resembles intrapulmonary right to left shunting but is caused by congenital cardiac malformations such as TOF TGA and EIsenmenger’s syndrome
Hypoxia secondary to R to L extrapulmonary shunting
reduction in hgb concentration of the blood is accompanied by a corresponding decline the oxygen carrying capacity of the blood
anemic hypoxia
COHb shifts the HB-O2 dissociation curve to the
a. left
b. right
A; oxygen is unloaded only at lower tensions, contributing to tissue hypoxia