GNUR 293 Exam 4 Questions And Answers With
Latest Updates
Ventilation ANS movement of air in and CO2 out of the lungs
ex: decrease ventilation = asthma or obstruction (air in)
Functional residual capacity ANS reserve of air that is left over in lungs after expiration
-decrease will occur in COPD, pregnant women, obese patients
-become hypoxic much quicker
Pulmonary function test (PFT) ANS evaluation of airflow in lungs
-used spirometer
-obstructive = can't get air out
-restrictive= can't get air in
Ventilation dead space: anatomic dead space ANS volume of gas not used in gas exchange (no
perfusion or diffusion-only in lungs)
-apex of lung "dead space"
Mechanics of breathing: airway resistance ANS -influenced by airway radius and pattern of gas flow
-stimulation of cholinergic fibers (PNS) = bronchoconstriction
-Stimulation of B2 adrenergic fibers (SNS) = bronchodilation
-turbulent flow increases resistance
-laminar flow decreases resistance
Mechanics of breathing: lung compliance ANS -influences the work of breathing
-represents lung expandability and ease of lung inflation
ex: skinny jeans/smaller balloon = low/decreased compliance; wide jeans/bigger balloon = high/increased
compliance
,Low compliance ANS -low volume inflation
-high pressure or effort
ex: fibrosis, stiff lung
High compliance ANS -high volume of inflation
-low pressure or effort
ex: COPD, loss of elastic
Are alveoli larger at base or apex of lung? ANS apex
Perfusion ANS -movement of blood in and out of capillary beds of lungs to body organs/tissues
ex: decrease perfusion = pulmonary emboli
Where is perfusion the highest in the lung? ANS The bottom or base or zone 3
aka lowest ventilation
-work of breathing is done here
Where is perfusion the lowest in the lung? ANS The top or apex or zone 1
aka highest ventilation
What is the ventilation to perfusion ratio? ANS 0.8
4 L/min of alveolar ventilation to 5 L/min capillary blood flow
Hypoventilation ANS -insufficient delivery of air to alveoli to meet need to provide O2 and remove
CO2
-increase PaCO2 (hypercapnia) due to decrease respiration
causes for hypoventilation ANS -morphine
-sleep apnea
,-damage to chest wall
-rib contusion
-paralysis of respiratory muscles
hyperventialtion ANS -increased air entering alveoli
-decreased PaCO2 < 35 mm Hg (hypocapnia) due to increase respirations
cause of hyperventilation ANS -pain
-fever
-anxiety
-obstructive and restrictive lung disease
-sepsis
-brain stem injury
Hypoxemia ANS deficient levels of blood O2
Hypoxia ANS decreased in tissue oxygen
High V/Q imbalance ANS ventilation with no perfusion
-physiologic dead space
Low V/Q mismatch ANS -Lower PaO2
-airways obstructed
-hypoxemia results
shunt effect ANS -results from blood flowing from the right side to the left side of heart without
passing through ventilated areas of the lung (localized pneumonia- alveoli are perfused but not ventilated)
Diffusion ANS passive movement of gas between air spaces in lungs and bloodstream (high
concentration to low concentration area)
, ex: change in diffusion = pulmonary edema, HF
What is the pathophysiology of pulmonary hypertension? ANS -walls of pulmonary vessels thicken
from an increase in the muscle
-becomes fibrotic
-sustained pulmonary HTN results in formation of a network of blood vessels (plexiform) that impede
blood flow
Treatment for pulmonary HTN ANS -supplemental O2
-vasodilators
-diuretics
-heart/lung transplant
-surgery if left to right shunt causing increased work for R ventricle
How doe HTN progress to Cor Pulmonale? ANS -Consequence of HF but more so from pulmonary
HTN
-*Eventually Cor Pulmonale and right ventricular failure will develop if severe pulmonary HTN
continues b/c of persistent back pressure to the right sided HF*
What causes pulmonary vasoconstriction? ANS hypercapnia, hypoxia, acidemia, increased H+
concentration
-not enough O2 getting into lungs so heart work load increases
-vasoconstriction causes increase in resistance/afterload which causes Cor Pulmonale (right sided HF)
What is Cor Pulmonale aka right sided HF? ANS an enlargement of the right ventricle due to high
blood pressure in the lungs caused by chronic lung disease
Clinical manifestations of Cor Pulmonale ANS -dyspnea
-syncope
-chest pain
-jugular venous distention
Latest Updates
Ventilation ANS movement of air in and CO2 out of the lungs
ex: decrease ventilation = asthma or obstruction (air in)
Functional residual capacity ANS reserve of air that is left over in lungs after expiration
-decrease will occur in COPD, pregnant women, obese patients
-become hypoxic much quicker
Pulmonary function test (PFT) ANS evaluation of airflow in lungs
-used spirometer
-obstructive = can't get air out
-restrictive= can't get air in
Ventilation dead space: anatomic dead space ANS volume of gas not used in gas exchange (no
perfusion or diffusion-only in lungs)
-apex of lung "dead space"
Mechanics of breathing: airway resistance ANS -influenced by airway radius and pattern of gas flow
-stimulation of cholinergic fibers (PNS) = bronchoconstriction
-Stimulation of B2 adrenergic fibers (SNS) = bronchodilation
-turbulent flow increases resistance
-laminar flow decreases resistance
Mechanics of breathing: lung compliance ANS -influences the work of breathing
-represents lung expandability and ease of lung inflation
ex: skinny jeans/smaller balloon = low/decreased compliance; wide jeans/bigger balloon = high/increased
compliance
,Low compliance ANS -low volume inflation
-high pressure or effort
ex: fibrosis, stiff lung
High compliance ANS -high volume of inflation
-low pressure or effort
ex: COPD, loss of elastic
Are alveoli larger at base or apex of lung? ANS apex
Perfusion ANS -movement of blood in and out of capillary beds of lungs to body organs/tissues
ex: decrease perfusion = pulmonary emboli
Where is perfusion the highest in the lung? ANS The bottom or base or zone 3
aka lowest ventilation
-work of breathing is done here
Where is perfusion the lowest in the lung? ANS The top or apex or zone 1
aka highest ventilation
What is the ventilation to perfusion ratio? ANS 0.8
4 L/min of alveolar ventilation to 5 L/min capillary blood flow
Hypoventilation ANS -insufficient delivery of air to alveoli to meet need to provide O2 and remove
CO2
-increase PaCO2 (hypercapnia) due to decrease respiration
causes for hypoventilation ANS -morphine
-sleep apnea
,-damage to chest wall
-rib contusion
-paralysis of respiratory muscles
hyperventialtion ANS -increased air entering alveoli
-decreased PaCO2 < 35 mm Hg (hypocapnia) due to increase respirations
cause of hyperventilation ANS -pain
-fever
-anxiety
-obstructive and restrictive lung disease
-sepsis
-brain stem injury
Hypoxemia ANS deficient levels of blood O2
Hypoxia ANS decreased in tissue oxygen
High V/Q imbalance ANS ventilation with no perfusion
-physiologic dead space
Low V/Q mismatch ANS -Lower PaO2
-airways obstructed
-hypoxemia results
shunt effect ANS -results from blood flowing from the right side to the left side of heart without
passing through ventilated areas of the lung (localized pneumonia- alveoli are perfused but not ventilated)
Diffusion ANS passive movement of gas between air spaces in lungs and bloodstream (high
concentration to low concentration area)
, ex: change in diffusion = pulmonary edema, HF
What is the pathophysiology of pulmonary hypertension? ANS -walls of pulmonary vessels thicken
from an increase in the muscle
-becomes fibrotic
-sustained pulmonary HTN results in formation of a network of blood vessels (plexiform) that impede
blood flow
Treatment for pulmonary HTN ANS -supplemental O2
-vasodilators
-diuretics
-heart/lung transplant
-surgery if left to right shunt causing increased work for R ventricle
How doe HTN progress to Cor Pulmonale? ANS -Consequence of HF but more so from pulmonary
HTN
-*Eventually Cor Pulmonale and right ventricular failure will develop if severe pulmonary HTN
continues b/c of persistent back pressure to the right sided HF*
What causes pulmonary vasoconstriction? ANS hypercapnia, hypoxia, acidemia, increased H+
concentration
-not enough O2 getting into lungs so heart work load increases
-vasoconstriction causes increase in resistance/afterload which causes Cor Pulmonale (right sided HF)
What is Cor Pulmonale aka right sided HF? ANS an enlargement of the right ventricle due to high
blood pressure in the lungs caused by chronic lung disease
Clinical manifestations of Cor Pulmonale ANS -dyspnea
-syncope
-chest pain
-jugular venous distention
