Cardiovascular and Respiratory Systems

1 gram of hemoglobin can carry

1.34 mL of oxygen

acidosis

blood pH < 7.35

aggregated platelets releases what secretions and what is their purpose? (hint: there are 5)

ADP = increase stickiness

serotonin = vasoconstriction

epinephrine = vasoconstriction

chemicals for blood coagulation

thromboxane A2 = amplification of platelet activation

air moves in and out of lungs by

bulk flow

alkalosis

blood pH \> 7.45

all systemic venous blood returns to the ________ and pumped out _________ into ________

right atriumright ventriclepulmonary artery

alveolar ventilation

The volume of air reaching the gas exchange areas over minute
AV = (Vt x RR) - (DSV x RR)

asthma caused by

spastic contractions of bronchiolar smooth muscle

autorhythmicity

the ability to generate own rhythm

baroreceptor reflex

negative feedback loop to maintain blood pressure at normal level (compensates for changes but does not correct them)

baroreceptors in arteries are located in

aortic arch and carotid sinuses(also called sinoaortic receptors)

capillary hydrostatic pressure

outward force, pushes fluid out of capillary (favors filtration)

Cardiac Output (CO)

volume of blood pumped by each ventricle per minute
CO = HR x stroke volume

central chemoreceptors respond mainly to changes in

pH of the CSF (do not care about O2 concentration)

Central Patern Generator (CPG)

establishes respiratory cycle

Diastole

ventricle relaxation

diastolic pressure

lowest level of aortic pressure

During muscle contraction in the heart, how do Ca2+ and troponin interact?

Ca2+ binds to troponin, which exposes myosin-binding sites and allows the cross bridge cycle to begin

Ejection Fraction (EF)

fraction of end diastolic volume ejected during a heartbeat
EF = stroke volume/end diastolic volume

End Diastolic Volume (EDV)

volume of blood in the ventricle at the end of diastole

End Systolic Volume (ESV)

volume of blood in ventricle at the end of systole

factors affecting airway resistance

passive forces (changes in transpulmonary pressure during respiration and tractive forces)contractile activity of smooth musclemucus secretion

factors affecting pulmonary ventilation

lung compliance and airway resistance

Factors determining intra-alveolar pressure

quantity of air in alveoli, volume of alveoli

FEV (forced expiratory volume)

percentage of FVC that can be exhaled within certain time frame (usually within one second)

fluid flows through capillary walls based on

pressure gradients (most plasma proteins do not flow into/out of capillaries)

forces for bulk flow consist of

hydrostatic and osmotic pressures

From largest to smallest, classify the forces affecting the movement of fluid across capillary walls

1. capillary hydrostatic pressure (16-38 mmHg)
2. capillary osmotic pressure (25 mmHg)
3. net filtration pressure (2 mmHg)
4. interstitial fluid hydrostatic pressure (1 mmHg)
5. interstitial fluid osmotic pressure (0 mmHg)

FVC (forced vital capacity)

maximum volume inhale followed by exhale as fast as possible

high mean arterial pressure results in

hypertension and extra stress on heart and blood vssels

How are action potentials and arterial pressure related?

as arterial pressure increases, the rate of action potential frequency increases

How do pacemaker cells give rhythm to the heartbeat?

spontaneously depolarizing membrane potentials to generate action potentials

How does epinephrine increase MAP during long-term regulation?

- increases TPR by acting on smooth muscle of arterioles- increases venomotor tone by acting on smooth muscle of veins- increases HR and SV by acting on the heart

How does the sympathetic nervous system effect ventricular contractility?

norepinephrine or epinephrine bind to beta-1 receptors and initiate a cAMP second-messenger system
produces a stronger and faster contraction

How does vasopressin and angiotensin II increase MAP during long-term regulation?

they are vasoconstrictors and increase TPR

How is calcium removed in the plasma membrane when cardiac muscles relax?

Ca2+ ATPase and Na+ - Ca2+ exchanger

How is calcium removed in the sarcoplasmic reticulum when cardiac muscles relax?

Ca2+ ATPase

How is cardiac output regulated?

extrinsic (neural and hormonal) and intrinsic (autoregulation)

How is platelet formation prevented from spreading past the damaged area?

prostacyclin and nitric oxide

Hydrostatic pressure gradient

force due to fluid

hyperpnea

increased ventilation due to increased demand
minimal changes in arterial P O2 and P CO2

hyperventilation

ventilation exceeds demands
arterial P O2 increase

arterial P CO2 decreases

hypoventilation

ventilation does not meet demands

arterial P O2 decreases

arterial P CO2 increase

If arterial pressure and afterload increases, what happens to the stroke volume?

stroke volume decreases

If the heart receives increased sympathetic activity, what is the influence on stroke volume?

increased sympathetic activity causes increased contractility which results in an increase in stroke volume

in the osmotic pressure gradient, what does capillary oncotic osmotic pressure and interstitial fluid oncotic osmotic pressure favor?

capillary = favors reabsorptioninterstitial = favors filtration
capillary \>> interstitial, which is why the overall osmotic pressure gradient favors reabsorption

Increases in CO2 causes what effect on ventilation

increases TPR and decreases HRusually results in increased MAP

internal respiration

also known as cellular respiration, which proceeds through oxidative phosphorylation

interstitial hydrostatic pressure

favors reabsorption

low FVOC indicates

restrictive pulmonary disease

low mean arterial pressure results in

hypotension and inadequate blood flow to tissues

lung compliance

the ease with which lungs can be expanded

main function of chemoreceptors in blood vessels

regulate blood CO2 levels (respond to higher rates of CO2)

Mean Arterial Pressure (MAP)

MAP = cardiac output (CO) x total peripheral resistance (TPR)
CO = heart rate (HR) x stroke volume (SV)

minute ventiltion

total volume of air entering and leaving respiratory system each minute
Minute ventilation = Vt x RR

osmotic pressure

osmotic force exerted on water by nonpermeating solutes (aka proteins)

osmotic pressure gradient favors

reabsorption

oxygen carrying capacity of hemoglobin in blood

200mL oxygen per L of blood

perfusion

rate of blood flow

peripheral chemoreceptors respond mainly to changes in

blood pH

platelets are also called

thrombocytes

pneumothorax

air in the pleural cavity caused by a puncture of the lung or chest wall (aka collapsed lung)

precapillary sphincters

control the blood flow into capillary beds from the arteriole end

Resistance to air flow is determined by

radius of airways and the amount of mucus

respiratory acidosis is caused by

increased CO2

respiratory alkalosis is caused by

decreased CO2

respiratory sinus arrhythmia during expiration and its effect on HR

increases parasympathetic activity and decreases HR

respiratory sinus arrhythmia during inspiration and its effect on HR

increases sympathetic activity which results in higher HR

role of coagulation factors in hemophilia

genetic disorder caused by deficiency of gene for specific coagulation factor

role of coagulation factors in vitamin K deficiencies

decreased synthesis of clotting factors

role of coagulation factors in Von Willebrand's disease

reduced levels of vWf and decreased platelet plug formation

Starling's Law

the more the heart fills during diastole (increased EDV), the more forcefully it contracts (increased SV)

Stroke Volume (SV)

volume of blood ejected from ventricle during each cycle
SV = EDV - ESV

surfactant is secreted from

type II alveolar cells

Systole

ventricle contraction

systolic pressure

highest point of pressure on arterial walls when the ventricles contract

The parasympathetic nervous system gives input to what parts of the cardiovascular system during regulation of MAP?

- SA node (decrease HR)- AV node

the respiratory control center of the pons regulates...

transitions between inspiration and expiration

The sympathetic nervous system gives input to what parts of the cardiovascular system during regulation of MAP?

- SA node (increase HR)- AV node- ventricular myocardium (increase contractility)- arterioles (increase resistance)- veins (increases venomotor tone)

transpulmonary pressure

difference between alveolar pressure and intrapleural pressure

Under what conditions do semilunar valves open?

when ventricular pressure is greater than arterial pressure

Under what conditions do the AV valves open?

when atrial pressure is greater than ventricular pressure

ventilation

rate of air flow

What affect does lower pH have on O2 saturation?

increases O2 unloading (Bohr effect)more O2 unloaded into tissues

what are obstructive pulmonary diseases associated with?

increased airway resistance

increased residual volume

increased functional residual capacity

decreased vital capacity

ex. COPD and asthma

what are restrictive pulmonary diseases associated with?

more difficult for lungs to expanddecreased total lung capacitydecreased vital capacity

what are the characteristics of an extra contraction in the heart?

premature atrial contraction (PAC) followed by an extra ventricular contraction
There is an extra systole

What are the components that effect amplitude and distance of spread in an ECG?

size of potentials and synchronicity of potentials from other cells

what are the conduction fibers of the myocardium?

internal pathways, bundle of His, and Purkinje fibers

what are the determinants of mean arterial pressure?

heart rate, stroke volume, and total peripheral resistance

What are the different waves, intervals, and segments of an ECG?

P --\> QRS --\> T (waves)PQ, QT (intervals)TQ, RR (segments)

What are the four factors the influence venous pressure and venous return?

- skeletal muscle pump (muscle contraction and relaxation)- respiratory pump (inspiration and abdominal pressure)- blood volume- venomotor tone

what are the four phases of the cardiac cycle?

1. ventricular filling
2. isovolumetric ventricular contraction
3. ventricular ejection
4. isovolumetric ventricular relaxation

what are the primary factors that affect stroke volume?

ventricular contractility

end diastolic volume

afterload (pressure in aorta during ejection)

what are the steps for forming a blood clot from fibrinogen?

thrombin activates the conversion of fibrinogen --\> fibrin (loose)then the loose fibrin stabilizes:fibrin (mesh) --\> fibrin clot = blood clot

What are the two main functions of metartierioles?

- directly connect arterioles and venules- function as shunts to bypass capillaries

What branch of the nervous system controls the SA node?

autonomic (parasympathetic at rest, sympathetic when excited) and hormones

what branch of the nervous system is responsible for extrinsic control of bronchiole radius?

Autonomic nervous system (epinephrine)sympathetic = bronchodilationparasympathetic = bronchoconstriction

What causes relaxation in capillary sphincters?

metabolites

What causes the dicrotic notch?

closure of the aortic valve causes backflow of blood which increases the pressure slightly