EPHE 160 - Cardiovascular System: Blood Pressure+hemmorhage

Which circulation system Pulmonary or Systemic has a higher blood pressure?

Systemic Circulation

Is blood pressure higher during systole or diastole?

Systole(contraction)

Equation for MAP

MAP = (SP + (2 X DP)) / 3

Normal Systemic Pressure

120/70

Whats a normal MAP?

85 mm Hg

What fraction of time is spent diastole v systole

diastole 2/3

systole 1/3

What are the risks with high blood pressure?

cardiovascular disease, poor circulation, kidney disease, stroke, decline in brain functions

What are the causes of hypertension

aging, atheroscleroriss, obesity, elevated insulin, inactivity

What are pre hypertension classifications

120-129 / <80

What are stage 1 hypertension classification

130-149 / 80-89

what are stage 2 hypertension classifications

≥140 / ≥90

What does it mean if you fall into higher BP classifications

double the risk of cardiovascular complications

What is considered low BP values?

<100 / <60

What is the Cardiovascular control centre

CV control centre is in Medulla Oblongata

• sends out info about response to effector organs

• cardiac output and overal peripheral resistance

Arterial Baroreceptors

Aortic Arch Baroreceptor and Carotid Sinus Baroreceptors

what is the parasympathetic response in the cardiovascular system

vasodilation in veins and arteries

decrease in hr in sa node

sympathetic response in cardiovascular system

vasoconstriction in veins +arteries, increase hr via sa node

Systolic and Diastolic Responses to Exercise

Diastolic Pressure should not increase with exercise → BV should dilate during exercise to maintain steady BP

Systolic pressure

• Trained up to 180 mmg Hg

• Untrained 150< you should stop

Mean Arterial Pressure EQ (CO+TPR)

MAP = CO x TPR

Why is blood doping during sporting events so dangerous?

blood doping increases the amount of Erythrocytes in your blood significantly increasing blood viscosity(TPR)

dehydration during exercise can increase blood viscosity as well (TPR)

blood clot risks increase hella leading to MI, embolisms, strokes etc.

these often lead to death in athletes during sporting events

Intrinsic Blood Flow Regulation

Local Controls that can inc/dec BP

myogenic responses → vasoconstriction

metabolic responses → increase blood flow to meet metabolic needs

Extrinsic Blood Flow Regulation

neural/hormone controls that can regulate BP

nervous system → sympathetic/parasympathetic stim

endocrine system → hormonal control

What are the two times when Cardiovascular controls are challenged?

Exercise and Hemorrhage

Hemorrhage effect on arterial blood pressure

dec blood volume = dec venous BP → dec venous blood return = dec atrial pressure → dec ventricular end-diastolic volume → dec cardiac muscle stroke volume → dec cardiac output → dec arterial BP

what are the four compensatory responses by arterial baroreceptors

1. dec parasympathetic stim to heart → incr HR

2. incr sympathetic stim to heart → incr HR + SV

3. incr sympathetic stim to veins → incr vasoconstriction in pveins

4. incr sympathetic stim to arterioles → incr vasoconstriction in arterioles

How does hemorrhage effect SV, HR, CO, TPR, MAP?

SV → dec

HR→ inc

CO → dec

TPR → inc

MAP → dec