cardio quiz 2

capillaries

Small blood vessels that connect arterioles and venules, facilitating the exchange of oxygen, carbon dioxide, nutrients, and waste between blood and tissues.

nicotinic receptor

parasympathetic receptor principally in the Central Nervous System

exchange of nutrients and gas between blood and tissues

what happens in capillaries

no smooth muscle, no innervation, no constriction or dilation

features of capillaries

edema

swelling caused by excess fluid accumulation in tissues

capillaries

where does edema occur

capillaries

vessel with the largest total cross-sectional area

decreases velocity

how does inceasing capillary cross sectional area affect velocity

provides sufficient time for capillary exchange

why is decreased velocity in capillaries important

large area decreases resistance which increases flow

how does large area affect resistance to flow

paracellular and transcellular

major methods of exchange across capillaries

paracellular exchange

exchange through fenestration or leak between capillary endothelial cells

transcellular exchange

exchange through transcytosis with vesicles or diffusion

gas exchange in lungs

example of transcellular exchange

starling forces equation

equation that describes the MOVEMENT OF FLUID across capillary membranes based on hydrostatic and oncotic pressures.

oncotic pressure

the osmotic pressure exerted by proteins in the blood plasma, particularly ALBUMIN, that helps to retain water in the circulation

filtration coefficient, describes fluid movement across capillary wall, increases with increased permeability

what is Kf

Pc

the hydrostatic pressure in the CAPILLARIES that drives fluid out of the vascular system

concentration of proteins, esp albumin

what is most responsible for osmotic pressure gradient

Pc-Pi

hydrostatic pressure gradient

decreases

what happens to capillary blood pressure over capillary lengths

πc-πi

osmotic pressure gradient

stays constant

what happens to papillary and interstitial osmotic pressure over capillary length

filtration out of capillary

positive net filtration

absorption into capillary

negative net filtration

infection/inflammation

 what may make tissues more leaky/ change Kf

increased Kf, increased hydrostatic pressure out of capillary, decrease oncotic pressure within capillary

causes of edema

decreased venous flow back to heart

how is hydrostatic pressure out of capillary increased

decreased albumin in blood

how is oncotic pressure within capillary decreased

drain excess interstitial fluid and return it to the bloodstream, maintaining fluid balance

purpose of lymphatic system

inadequate removal of fluid

problems in lymphatic system that lead to edema

radical lymph node dissection

common cause to lymphedema

increase Pi (compression or massage and increase πc (increase protein)

treatment of lymphedema

somatic and autonomic

divisions of peripheral nervous system

parasympathetic and sympathetic

divisions of autonomic system

autonomic nervous system

A part of the peripheral nervous system that controls involuntary bodily functions, including heart rate, digestion, and respiratory rate

T1-L2

origin of SYMPATHETIC nervous system

cranial and sacral areas

origin of parasympathetic nervous system

both provide input but strength varies

how do the parasympathetic and sympathetic nervous systems work togetheer

dilate pupils, raise heart rate, dilate bronchia

examples of sympathetic reactions

constrict pupils, decrease heart rate, constrict bronchia

examples of parasympathetic reactions

norepinephrine and epinephrine

neurotransmitters associated with sympathetic tone

acetylcholine

neurotransmitter associated with parasympathetic tone

muscarinic receptors

a type of receptor that mediates parasympathetic responses in the body, influencing functions like heart rate and glandular secretion.

anti-cholinergic medication

medications that inhibit acetylcholine

xerostomia

common side effect of anti-cholinergic medication

muscarinic agonist

drugs that mimic the action of acetylcholine and stimulate salvation to treat xerostomia 

pilocarpine

example of muscarinic agonist

muscarinic antagonist

drugs that block action of acetylcholine and have anti-cholinergic side effects

COPD

what are muscarinic antagonists used to treat

 alpha1, alpha2, beta1, beta2

sympathetic receptors

Beta 1

sympathetic receptor primarily found myocardial cells, responsible for INCREASING heart rate and contractility

alpha 1

sympathetic receptor primarily found in vascular smooth muscle, responsible for VASOCONSTRICTION

alpha 2

sympathetic receptor primarily found in vascular smooth muscle, responsible for VASORELAXATION

beta 2

sympathetic receptor primarily found in bronchial smooth muscle, responsible for BRONCHODILATION.

Beta 1 and Beta1/2 Antagonists

drugs that DECREASE sympathetic tone to control heart rate

beta 2 agonists

drugs used to INCREASE sympathetic tone for COPD and asthma

baroreceptors

specialized sensory receptors that detect changes in blood pressure and help regulate cardiovascular function

decreases sympathetic increases parasympathetic

what happens if baroreceptors detect high blood pressure

tachycardia

elevated resting heart rate

autonomic neuropathy

condition in which nerves that control sympathetic or parasympathetic functions are damaged

irregular heart rate

sign of autonomic neuropathy

parasympathetic

what branch of ANS is malfunctioning in a patient with elevated resting heart rate

orthostatic hypotension

dizziness and lightheadedness when standing due to blood pressure drop 

diabetic autonomic neuropathy

complication of diabetes that affects nerves of autonomic nervous system

aortic arch and carotid sinus

location of baroreceptors

deliver oxygen and nutrients, remove metabolic wastes

main purposes of cardiovascular system

increases when demand increases

how does distribution of blood flow change with bodies needs

cardiac output

blood flow heart can create

CO= stroke volume x heart rate

cardiac output equation

pumping heart, regulated by smooth muscles

how is flow created in arterial side

increasing venous return

how is flow increased on venous side

stroke volume

the amount of blood pumped by the heart with each beat.

capillaries

what slows down flow from arterial to venous sides

increasing venous return

how is cardiac output increased

skeletal muscle pumps, inspiration (inhalation), sympathetic innervation to veins

how is venous return increased

skeletal muscle pumps

muscles contracted and venous valves above muscle opens and blood moves through

inspiration (inhalation)

decreased pressure in thorax pulls blood into vena cava

sympathetic innervation to veins

increased tone of veins due to sympathetic vasoconstriction

 Poiseuille Equation

DEESCRIBES the FLOW of fluid through a cylindrical pipe, relating pressure, radius, and viscosity, Q=∆P/R

flow

Q of Poiseuille Equation

change in blood pressure

∆P in poiseuille equation

vascular resistance

R in poiseuille equation

fluid moves from high to low pressure, higher pressure = higher flow

How does pressure affect flow?

systolic blood pressure

pressure in arteries when heart contracts

pressure in arteries when heart rests between beats

diastolic blood pressure

heart spends more time in diastole than systole

why is MAP (mean arterial pressure) closer to DBP (diastolic) than SBP (systolic)

arteries stiffen

why does blood pressure change as we age

systolic increases, diastolic decreases

what happens to blood pressure as we age

decreases

how does blood pressure change across the circulatory system

arterioles

where can blood flow be most controlled in body

large number of capillaries arranged in parallel

why is resistance low in capillaries

radius of arteriole

most important factor that regulate flow in vascular system

rapidly constrict or dilate regulating blood flow

why are artereioles most important in control of blood flow

large total cross-sectional area

why is resistance so low in capillaries even though their radius is small

contraction and relaxation of arteriolar smooth muscle

what controls flow in arterioles

epinephrine, angiotensin II, vasopressin, norepinephrine

extrinsic factors that determine vascular tone (tension of smooth muscle)

myogenic and metabolic autoregulation

intrinsic factors that determine vascular tone

myogenic autoregulation

Intrinsic property of the vessels to “bounce back” to original tension

metabolic autoregulation

Muscle cells at the vessels dilate with increased metabolism or after a flow
blockage