NR 224 FUNDAMENTALS QUESTIONS AND ANSWERS/ A+ GRADE
Oxygen
necessary to sustain life
cardiac and respiratory systems supply O2 demands of the body
blood is oxygenated through ventilation, perfusion, and transport
neural and chemical regulators control rate and depth of respiration
Structure and function
respiratory muscles, pleural space, lungs, and alveoli essential for breathing
intrapleural pressure is negative, less than atmospheric pressure
Ventilation
process of moving gases into and out of lungs
requires coordination of muscular and elastic properties of lung and thorax
Diaphragm
major inspiratory muscle of respiration
innervated by phrenic nerve (exits spinal cord at fourth cervical vertebra)
Perfusion
relates to ability of cardiovascular system to pump oxygenated blood to tissues and
return deoxygenated blood to lungs
Diffusion
responsible for moving respiratory gases from one area to another by concentration
gradients
Work of breathing (WOB)
effort required to expand and contract the lungs
healthy individual - quiet and accomplished with minimal effort
amount of energy expended on breathing depends on rate and depth of breathing,
compliance, and airway resistance
Compliance
ease in which the lungs can be expanded
Inspiration
an active process, stimulated by chemical receptors in the aorta
Expiration
passive process that depends on the elastic recoil properties of the lungs, requiring little
or no muscle work
Surfactant
chemical produced in lungs to maintain surface tension of the alveoli and keep them
from collapsing
COPD patients - lose elastic recoil of lungs and thorax
Atelectasis
collapse of alveoli that prevents normal exchange of oxygen and carbon dioxide
Airway resistance
the increase in pressure that occurs as the diameter of the airways decreased from
mouth/nose to alveoli
any further decrease in airway diameter by bronchoconstriction can increase airway
,resistance
(asthma, tracheal edema)
Lung volumes
determined by age, gender, height
Tidal volume
amount of air exhaled after normal inspiration
Residual volume
amount of air left in the alveoli after a full expiration
Forced vital capacity
max amount of air that can be removed from lungs during forced expiration
Pulmonary circulation
primary function is to move blood to and from the alveolar capillary membrane for gas
exchange
begins at pulmonary artery
Oxygen-transport system
consists of lungs and cardiovascular system
delivery depends on amount of oxygen entering lungs, blood flow to lungs and tissues,
rate of diffusion, and oxygen-carrying capacity
Influence the capacity of blood to carry oxygen
amount of dissolved oxygen in plasma, amount of hemoglobin, and tendency of
hemoglobin to bind with oxygen
Hemoglobin
carrier for oxygen and carbon dioxide, transports most oxygen (97%)
Carbon dioxide
product of cellular metabolism
diffuses into red blood cells
rapidly hydrated into carbonic acid (H2CO3)
Regulation of respiration
necessary to ensure sufficient oxygen intake and carbon dioxide elimination to meet the
demands of the body
(exercise, infection, pregnancy)
Neural regulation
includes CNS control of respiratory rate, depth, and rhythm
voluntary control regulated by cerebral cortex
Chemical regulation
maintains appropriate rate and depth based on changes in CO2, O2, and H+ (pH conc.)
Cardiopulmonary physiology
involves delivery of deoxygenated blood to right side of heart and then to lungs to be
oxygenated
Myocardial pump
pumping action of the heart
essential to deliver oxygen
Stroke volume
volume of blood ejected from ventricles during systole
hemorrhage and dehydration cause decrease in circulating blood volume and decrease
in stroke volume
, Frank-Starling law of the heart
as myocardium stretches, the strength of the subsequent contraction increases
Myocardial blood flow
must supply sufficient oxygen and nutrients to myocardium to maintain adequate blood
flow to pulmonary and systemic circulation
Coronary circulation
branch of the systemic circulation that supplies myocardium with oxygen and nutrients
and removes waste
Systemic circulation
these arteries deliver nutrients and oxygen to tissues and veins remove waste from
tissues
Cardiac output
amount of blood ejected from the left ventricle each minute
normal is 4 to 6 L/min
Stroke volume (SV) x Heart rate (HR)
Preload
amount of blood in the left ventricle at the end of diastole
Afterload
resistance to left ventricular ejection
Myocardial contractility
affects stroke volume and cardiac output
Cardiac conduction system
generates and transmits the electrical impulses
needed to initiate the electrical chain of events for a normal heartbeat
Autonomic nervous system
influences the rate of impulse generation and speed of transmission through the
conductive pathway and strength of atrial and ventricular contractions
SA node
pacemaker of the heart
conduction system originates here
AV node
mediates impulses between atria and ventricles
assists atrial emptying by delaying impulse before transmitting through bundle of His
and ventricular Purkinje network
Electrocardiogram (ECG)
reflects electrical activity activity of conduction system
monitors regularity and path of electrical impulse through conduction system
does not reflect muscular work of heart
normal sinus rhythm (NSR)
normal sequence on the ECG
implies that the impulse originates at SA node, follows the normal sequence through
conduction system
QRS complex
indicates that the electrical impulse traveled through the ventricles
normal QRS duration is .06 to .1 second
Oxygen
necessary to sustain life
cardiac and respiratory systems supply O2 demands of the body
blood is oxygenated through ventilation, perfusion, and transport
neural and chemical regulators control rate and depth of respiration
Structure and function
respiratory muscles, pleural space, lungs, and alveoli essential for breathing
intrapleural pressure is negative, less than atmospheric pressure
Ventilation
process of moving gases into and out of lungs
requires coordination of muscular and elastic properties of lung and thorax
Diaphragm
major inspiratory muscle of respiration
innervated by phrenic nerve (exits spinal cord at fourth cervical vertebra)
Perfusion
relates to ability of cardiovascular system to pump oxygenated blood to tissues and
return deoxygenated blood to lungs
Diffusion
responsible for moving respiratory gases from one area to another by concentration
gradients
Work of breathing (WOB)
effort required to expand and contract the lungs
healthy individual - quiet and accomplished with minimal effort
amount of energy expended on breathing depends on rate and depth of breathing,
compliance, and airway resistance
Compliance
ease in which the lungs can be expanded
Inspiration
an active process, stimulated by chemical receptors in the aorta
Expiration
passive process that depends on the elastic recoil properties of the lungs, requiring little
or no muscle work
Surfactant
chemical produced in lungs to maintain surface tension of the alveoli and keep them
from collapsing
COPD patients - lose elastic recoil of lungs and thorax
Atelectasis
collapse of alveoli that prevents normal exchange of oxygen and carbon dioxide
Airway resistance
the increase in pressure that occurs as the diameter of the airways decreased from
mouth/nose to alveoli
any further decrease in airway diameter by bronchoconstriction can increase airway
,resistance
(asthma, tracheal edema)
Lung volumes
determined by age, gender, height
Tidal volume
amount of air exhaled after normal inspiration
Residual volume
amount of air left in the alveoli after a full expiration
Forced vital capacity
max amount of air that can be removed from lungs during forced expiration
Pulmonary circulation
primary function is to move blood to and from the alveolar capillary membrane for gas
exchange
begins at pulmonary artery
Oxygen-transport system
consists of lungs and cardiovascular system
delivery depends on amount of oxygen entering lungs, blood flow to lungs and tissues,
rate of diffusion, and oxygen-carrying capacity
Influence the capacity of blood to carry oxygen
amount of dissolved oxygen in plasma, amount of hemoglobin, and tendency of
hemoglobin to bind with oxygen
Hemoglobin
carrier for oxygen and carbon dioxide, transports most oxygen (97%)
Carbon dioxide
product of cellular metabolism
diffuses into red blood cells
rapidly hydrated into carbonic acid (H2CO3)
Regulation of respiration
necessary to ensure sufficient oxygen intake and carbon dioxide elimination to meet the
demands of the body
(exercise, infection, pregnancy)
Neural regulation
includes CNS control of respiratory rate, depth, and rhythm
voluntary control regulated by cerebral cortex
Chemical regulation
maintains appropriate rate and depth based on changes in CO2, O2, and H+ (pH conc.)
Cardiopulmonary physiology
involves delivery of deoxygenated blood to right side of heart and then to lungs to be
oxygenated
Myocardial pump
pumping action of the heart
essential to deliver oxygen
Stroke volume
volume of blood ejected from ventricles during systole
hemorrhage and dehydration cause decrease in circulating blood volume and decrease
in stroke volume
, Frank-Starling law of the heart
as myocardium stretches, the strength of the subsequent contraction increases
Myocardial blood flow
must supply sufficient oxygen and nutrients to myocardium to maintain adequate blood
flow to pulmonary and systemic circulation
Coronary circulation
branch of the systemic circulation that supplies myocardium with oxygen and nutrients
and removes waste
Systemic circulation
these arteries deliver nutrients and oxygen to tissues and veins remove waste from
tissues
Cardiac output
amount of blood ejected from the left ventricle each minute
normal is 4 to 6 L/min
Stroke volume (SV) x Heart rate (HR)
Preload
amount of blood in the left ventricle at the end of diastole
Afterload
resistance to left ventricular ejection
Myocardial contractility
affects stroke volume and cardiac output
Cardiac conduction system
generates and transmits the electrical impulses
needed to initiate the electrical chain of events for a normal heartbeat
Autonomic nervous system
influences the rate of impulse generation and speed of transmission through the
conductive pathway and strength of atrial and ventricular contractions
SA node
pacemaker of the heart
conduction system originates here
AV node
mediates impulses between atria and ventricles
assists atrial emptying by delaying impulse before transmitting through bundle of His
and ventricular Purkinje network
Electrocardiogram (ECG)
reflects electrical activity activity of conduction system
monitors regularity and path of electrical impulse through conduction system
does not reflect muscular work of heart
normal sinus rhythm (NSR)
normal sequence on the ECG
implies that the impulse originates at SA node, follows the normal sequence through
conduction system
QRS complex
indicates that the electrical impulse traveled through the ventricles
normal QRS duration is .06 to .1 second
