Special Circlulations Flashcards
Where does the bronchial circulation go to
To the lungs (allows the perfusion)
Would start at the aorta
Where would the pulmonary circulation go to
The lungs and the heart
What vessels would have the anastomoses
Cerebral
Bronchial
Cutaneous
What would be special about the pulmonary circulation
Low pressure
Low resistance
What is the pressure in the bronchial system equal to
The systemic circulation
What is chronic hypoxia
When would have the hypoxic vasoconstriction but would be wide spread
Increased pressure and pulmonary hypertension
What are the adaptions of the pulmonary circulation
High branching
Short diffusion distance
High capillary density
Hypoxic vasoconstriction (allowing perfusion to some areas)
How does gravity effect the vessels in the lungs
When standing (orthostasis) would have the greater hydrostatic pressure on the basal vessels
What happens to the apical capillary’s in diastole
Would be collapsed
What happens to the apical capillary’s of the lung in excersise
Would open
What are the adaptations of the coronary circulation
High capillary density
Continuous production of NO - allows vasodilation
Reactive hyperaemia (local vasodilation)
What type of artery’s would the coronary circulation have
End artery’s and so would not have any anastomoses
What is reactive hyperaemia
When would have the productions of the local metabolites
This would then allow the local vasodilation
What is special about NO
Would be a vasodilatior
What are the adaptions of the cerebral circulation
High basal rate
High capillary density
High oxygen extraction
Short diffusion distance
What is the circle of wilis
Anastomoses of the artery’s between the BASAL and INTERNAL CAROTID artery’s
What is the cushings reflex of the brains
When have the increase inter-cranial pressure (fluid or a tumour)
Brain would respond
Increased sympathetic stimulation - increased blood flow and pressure
If not would then have cushings triad
What is the cushings train
Bradycardia
Systolic hypertension
Irregular respiration
What is myogenic auto regulation
Increased blood flow and pressure - vasoconstriction
Decreased blood flow and pressure - vasodilation
Would then maintain the constant blood flow
How is the skeletal circulation adapted to deal with the increased work load
Pre-capillary sphincters would close at rest
This would lead to the high vascular tone and the vasoconstriction
So would then deal with the increased work load of the muscles
Where else would metabolic hyperaemia happen
The skeletal muscles
(As well as the coronary)
What is the metabolic activity of the cutaneous circulation
Low - mainly temp regulation
What does the skin have instead of capillary’s
Arteriovenous anastomoses
How would the temp regulation of the skin work
Hypothalamus detects
Change in the sympathetic response
Would then allow the vasoconstriction or dilation
Heat contained or released
What nervous system do most circulations use
The sympathetic system
What is metabolic hyperaemia
When have the high co2
Would the increase the flow and pressure
More oxygen to the tissues
What are the factors that would mean that the pulmonary system would be a low resistance system
Wider and shorter capillary’s
Less smooth muscle cells on the arterioles
Capillary’s would run in parallel
