Control of arterial blood pressure Flashcards
What is blood pressure?
The outwards pressure exerted by the blood on blood vessel walls
What is systemic systolic arterial blood pressure?
is the pressure exerted by the blood on the walls of the aorta and systemic arteries when the heart contracts”
What is systemic diastolic arterial blood pressure?
is the pressure exerted by the blood on the walls of the aorta and systemic arteries when the heart relaxes”
what is hypertension?
Clinic blood pressure of 140/90 mmHg or higher and day time average of 135/85 mmHg or higher
What is pulse pressure?
The difference between the systolic and diastolic blood pressures
What is the normal range for pulse pressures?
between 30 and 50
What does laminar mean in terms of blood pressure?
There is fluent flow, no obstruction. You will not hear anything.
Is turbulent flow heard through a stethoscope?
Yes
How is turbulent flow created?
If the external pressure is kept between systolic and diastolic
When artery is fully occluded by sphyg what can you hear?
Nothing.
What is the first Korotkoff sound?
The first sound heard at peak systolic pressure
What are the second and third Korotkoff sounds?
Intermittent sounds are heard as blood pressure due to turbulent spurts of flow cycle cyclically exceeds cuff pressure
What is the 4th Korotkoff sound?
The last sound heard at minimum/diastolic pressure. Muffled/muted sound
What is the 5th Korotkoff sound?
No sound is heard thereafter because of uninterrupted smooth laminar flow.
What are the two important sounds for measuring BP?
1st and 5th (systolic and diastolic values)
What is a pressure gradient?
What drives the blood around the systemic circulation
What is the equation for pressure gradient?
mean arterial Pressure - central venous pressure
What is mean arterial blood pressure?
the average arterial blood pressure during a single cardiac cycle, which involves contraction and relaxation of the heart
What is the equation for mean arterial blood pressure?
-((2xdiastolic) + systolic)/3
or
-diastolic blood pressure +1/3xpulse pressure
Why dies the mean arterial blood pressure need to be regulated within narrow range limits?
- pressure needs to be high enough to perfuse internal organs including the brain, heart, and kidneys
- But not so high as to damage the blood vessels or place an extra strain on the heart