Section 5 Exam 2 Flashcards
In this type of lung disease, both the FEV1 and FVC are reduced so the FEV1/FVC ratio is normal or even increased
restrictive
in this type of lung disease the FEV1 /F CV ratio is reduced:
obstructive lung disease
All restrictive lung diseases result in:
decreased TLC, increased work of breathing, inadequate ventilation and/or oxygenation and decreased FVC (restrict lung expansion)
Affect of the respiratory system on prostoglandins:
turns off
Affect of respiratory system on angiotensin II:
turns it on
inflammation of the pleural sac:
pleurisy
Does pressure increase or decrease with altitude?
decrease
Intra-alveoloar pressure is aka:
intrapulmonary pressure
intrapleural pressure is aka:
intrathoracic pressure
What is the intraplural/ thoracic pressure?
756 mm Hg
What 2 pressures push against intrapleural pressure?
atmospheric and intra-alveolar
Which gradient will be destroyed with a pneumothorax?
transmural
The diaphragm is responsible for __% of enlargement of thoracic cavity during inspiration.
75%
What 2 pressures are equal before inspiration/
intra-alveolar p. = atm. p.
Contraction of external intercostals enlarges cavity in what direction(s)?
lateral and AP (elevate ribs when contracting)]
True or False? Alveolar pressure is positive during inhalation and negative during expiration.
F. vice versa
What ensures that lungs will be fully expanded?
intrapleural pressure
Range of pressure in lungs during ventilation:
759 - 761 mm Hg
During forceful expiration, ___ pressure exceeds ___ pressure
intrapleural, atmospheric pressure (intra-alveolar increases too)
driving pressure is proportional to:
square of flow (V2)
What type of infections are patients with chronic bronchitis prone to?
bacterial
True or False? Airway lining thicken with chronic bronchitis.
T
Most common chronic childhood disease:
asthma
What can cause edema in asthmatic kids?
histamine
True or False? The breakdown of alveolar walls in emphysema is reversible.
F. irreversible
What causes the breakdown of alveolar walls in emphysema?
excessive trypsin from alveolar macrophages as defense against cigarette smoke irritants (lungs normally protected by α1-antitrypsin, but can be overwhelmed) OR genetic inability to produce α1-antitrypsin
Do asthma and emphysema start in small or large airways ?
small
Frictional resistance in airways accounts for __ % total R in the way to the alveoli.
80
Frictional resistance of the ______ makes up 20% total R on the way to the alveoli.
lungs and chest wall
Amount of air that gets to alveoli depends on:
muscle strength, airway resistance, elasticity/ compliance, and inertence (energy to set the system in motion)
Normal compliance is:
200 cm/ml H2O
This is a measure of the amount of change in volume for a given transmural pressure:
compliance
Why is compliance different for expiration/inspiration?
b/c of surfactant – hysteresis
How is static compliance measured?
without airflow
How does surfactant lower surface tension at the molecular level?
because water-surfactant attraction is not as strong as water-water
True or False? Surfactant reduces lung’s tendency to recoil
T
What does the inward-directed collapsing pressure of the alveolus depend upon?
2 times the surface tension divided by the radius of the alveolus
____ airways are more likely to collapse than ____ ones
smaller, larger
Why is surfactant more effective at lowering surface tension in smaller airways?
less spread out
Which are easier to stretch, saline-filled or air-filled lungs?
saline-filled
__% of total energy expended by body goes to breathing
3-5%, can increase 50-fold in exercise
How are intrapleural and intra-alveolar pressures affected by tidal volume increase?
intrapleural and intra-alveolar pressures decrease in direct proportion
Normal FEV1/ FVC %:
greater than 70%
What factors are normal restrictive lung diseases?
flow and resistance
What factors are decreased in restrictive lung diseases?
vital capacity, FEV1, and FVC
Causes of restrictive lung diseases:
leasions, obesity, pregnancy, ascite, interstitial lung disease
Lung volumes below ___% of predicted values are considered restrictive lung diseases.
80%
Can cause lung volumes to be smaller than predicted:
fibrosis, kyphoscoliosis (both increased elastic recoil) and pleural effusion (lung compression)
How does increased surface area affect DLCO?
reduces it
measurement of dissolved tensions of CO2 and O2 as well as pH of sample of arterial blood:
Arterial blood gas determination (ABGs)
How much can the respiratory (minute) ventilation increase with exercise?
25 times (to 150 L/min)
How many ml is used for gas exchange?
350ml
Can alveolar ventilation increase or decrease if respiratory ventilation remains the same?
Yes, breath slowly and deeply: alveolar ventilation increases; breath shallowly and rapidly: alveolar ventilation decreases
What prevents fluctuation in alveolar gas tensions with each tidal breath?
reservoir of gas ‘stored’ within alveoli
easy to fill lungs, hard to empty:
obstructive lung disease
most efficient way to increase alveolar ventilation:
Increase tidal volume
True or False? Increase respiratory rate and alveolar ventilation increases.
T
How is dead space affected with an increase in respiratory rate?
dead space increases
physiologic dead space calculation:
sum of anatomical & alveolar dead space
Is pleural pressure more negative at top or bottom of the lungs?
top
True or False? The larger alveoli are at the bottom of the lungs.
F. Top
Where is there a greater distending pressure for alveoli?
at top of lungs
Which regions of lung are better perfused, upper or lower?
lower
Why is the upper lungs less perfused than lower?
gravity, hydrostatic pressure gradient of 30 cm water
Pressure gradient in which a patient has hemorrhaged (BP, intravascular volume are low):
Alveolar > arterial, not in healthy patient
Pressure gradient for flow driven by difference between arterial/alveolar pressure; primary area of distension, recruitment of vessels during exercise:
arterial > alveolar > vein
In which zone does continuous forward flow through distended vessels occur?
Zone 3
What zone is this? Flow driven by difference between arterial/alveolar pressure; primary area of distension, recruitment of vessels during exercise
Zone 2
With airways obstruction, will FRC increase or decrease?
increase (premature airway closure)
What causes pulmonary edema?
left heart failure
Which form of oxygen in the blood is responsible for partial pressure?
dissolved
This is often given given post-surgery to boost blood oxygen content:
EPO
volumes percent of oxygen in blood:
20
What affect will blood doping have on blood viscosity?
increases it (increasing resistance)
Factors that would lead to a decreased P50:
decreased temperature, decreases CO2 pressure, decreased 2,3-DPG, increased pH
Does a decreased P50 correspond with an increased or decreased affinity?
increased
What shape is the CO2 dissociation curve/
linear
True or False? Oxygen and carbon dioxide bind the same site.
F. high oxygen reduces affinity
Parasympathetic affect on the lungs:
airway constriction, blood vessels dilation, glandular secretion
Does nonadrenergic noncholinergic activation lead to realization or stimulation?
stimulation
Does nonadrenergic noncholinergic inhibitory activation lead to relaxation or stimulation?
relaxation
In which direction will the Hb curve shift with a decrease in pH?
Right
True or False? Oxygen and CO2 bind the same site of hemoglobin.
F.
