Test 5 Study Guide Part 2 Flashcards
Boyle’s law:
- Define:
- Relation to lungs:
- Define:
P1V1 = P2V2 - Relation to lungs:
Increasing volume of lungs decreases it’s pressure
The ability to enlarge, expand, inflate:
Compliance:
Tendency of a structure to return to its original size
Elasticity:
What reduces the the compliance of the lungs?
Elasticity Surface tension (water within alveoli)
Units for lung compliance:
ΔV/ΔP
where P is transpulmonary pressure
Why does pulmonary fibrosis decrease the lungs compliance?
Infiltrate the lungs with connective tissue proteins. Results in less expansion per a given change in pressure
Why are the lungs always in a state of elastic tension?
They are stuck the the chest wall, so they are always pulling away from it, and the ribs are always pulling away from them
lungs control fluid levels within alveoli:
- Drives fluid into alveolar walls:
- Drives fluid out of alveolar walls:
- Drives fluid into alveolar walls:
Active transport of Na+ into cells - Drives fluid out of alveolar walls:
Active transport of Cl- out of cells
What defect causes cystic fibrosis?
one in cystic fibrosis transmembrane regulator, a Cl- channel (CFTR is the only ABC family protein to act as a channel). Reduced ability to excrete water into alveoli results in viscous (low water content) mucous which is difficult to clear.
Surfactant:
- Define:
- Helps the lung’s get around which law?
A film of lipoprotein lining the alveoli, which lowers surface tension
Laplace law
Laplace law:
- Define:
- What does it imply?
- Why is this not the case?
- Define: Pressure created by surface tension P = (2 * T) / r - What does it imply? Smaller alveoli should be under more surface tension - Why is this not the case? surfactant
Surfactant two predominant phospholipids:
posphatidylcholine
phosphatidylglycerol
When does surfactant begin to be produced?
Late in fetal life
An normal infants first breath must overcome a transpulmonary pressure 15 to 20x that of subsequent breaths.
Why?
Many of its alveoli are collapsed, after the first breath, surfactant will stop them from collapsing again.
What difficulty must an infant born before surfactant production deal with?
Every breath must overcome collapsed alveoli. Must a transpulmonary pressure 15-20x a normal infants for each breath
What contributes to the elastic component of exhalation:
Elasticity of the lungs
Elasticity of intercostal muscles
Elasticity of the bone (sternum, ribs) as they move back into place
Intercostals involved in intense forceful breathing
internal intercostal muscles
INTense INTernal
Intercostals involved in restful breathing
External intercostals
Which other thoracic muscles become involved in respiration?
Pectoralis minor
Sternocleidomastoid muscles
Scalenes
Forced exhalation:
- Muscles which contribute:
- Muscles which contribute:
Intercostal muscles
Abdominal muscles
Vital Capacity:
The maximum amount of air which can be expelled after taking the greatest breath possible
What device measures the amount of breath inhaled or exhaled
- What is a test like this called?
spirometer
Pulmonary function test
Spirogram:
A graph of the amount exhaled/inhaled as measured by a spirometer
Spirometer:
- Capacity vs Volume:
- Capacity vs Volume:
A capacity is the sum of two or more volumes
(total lung capacity for example is residual volume + other volumes, don’t learn this example)
Lung disorder:
- Restrictive disorder:
- Example of a Restrictive disorder:
- Restrictive disorder:
Vital capacity is decreased in the disorder. Difficult to inhale full capacity - Example of a Restrictive disorder:
Pulmonary fibrosis
Lung disorder:
- Obstructive disorder:
- Example of a obstructive disorder:
- Obstructive disorder: Forced expiratory volume is lower, vital capacity is usually normal Difficulty exhaling - Example of a obstructive disorder: Asthma
The percentage of your vital capacity which can be forced from you lungs in the first second:
Forced expiratory volume
A Forced expiratory volume less then 80% is indicative of what?`
An obstructive respiratory disorder
A subjective feeling of shortness of breath:
Dyspnea
Multiplying the volume of one breath by the number of breaths in a minute
Total minute volume:
Allergic asthma is the most common, it is also called:
Atopic asthma
Children who grow up getting messy on farms or with pets and siblings are more or less likely to get asthma/allergies?
Less likely
Chronic obstructive pulmonary disease (COPD):
- Define:
- Results in:
- Example:
- Define:
Chronic inflammation from narrowing airways and destruction of alveolar walls. - Results in:
accelerated age-related decline in the FEV1 - Example:
Emphysema
Emphysema:
- Symptoms:
- Causative agents:
- Symptoms:
Reduction of the number of alveoli but increase in their size (reduces surface area
Air trapping, collapse of bronchiole stopping air from escaping from some alveoli - Causative agent:
Smoking (90% are or have been smokers)
Pollution
Emphysema:
- How does smoking and pollution cause the symptoms of emphysema:
- How does smoking and pollution cause the symptoms of emphysema:
Inflammation is promoted by new antigens -> macrophages, neutrophils, T lymphocytes arrive in lung -> excrete proteases, elastases and destroy extracellular matrix -> alveoli devolve/emphysema
Elastase in the emphysema immune responses is secreted by:
Neutrophils
What is a specific protease secreted by alveolar macrophages?
Matrix metalloproteinases
Why is asthma not a chronic obstructive pulmonary disease?
It is largely reversible when you take an inhaler (albuterol).
It is characterized by airway hyperresponsiveness
Barrel shape chest in emphysema is a sign of what?
- hyperinflammation
- air trapping
How will emphysema change the following?
- CO2 levels?
- Plasma pH?
- Oxygen levels?
- Hematocrit?
- CO2 levels? rise - Plasma pH? lower - Oxygen levels? lower - Hematocrit? rise
Once a COPD develops, does stopping smoking reverse it?
No. It does not.
Pulmonary hypertension and hypertrophy the right ventricle, and lead to right ventricular failure.
Cor Pulmonale:
Chronic pulmonary disease in addition to issues mentioned can cause:
Pneumonia
pulmonary emboli
heart failure (from cor pulmonale)
Pulmonary fibrosis:
- What type of lung disease?
- Define:
- general cause:
- What type of lung disease?
Restrictive lung disease - Define:
normal structure of lungs is disrupted by fibrous connective tissue - general cause:
Accumulation of particles less than 6 um in size in the respiratory zone
Anthracosis:
- Other name?
- Causes?
- Other name?
black lung - Causes?
pulmonary fibrosis
1 atmosphere in mm/hg is:
760 mm/hg
Total pressure of a mixture gas is the sum of the partial pressures of each gas in the mixture
P = P1 + P2 + P3 + P4
Dalton’s law:
Every ___ feet below sea level is equivalent to another atmosphere of pressure:
33 feet
Inspired air versus alveolar air:
- O2:
- CO2:
- H20:
- Why?
- O2: Lower (159 -> 105 mmHg) - CO2: (higher (.4mmHg -> 40 mmHg) - H20: Constant (Variable -> 47 mmHg) - Why? Increased levels of H2O decreases relative partial pressures of all other gasses. CO2 and O2 change because of metabolism and use/production.
The amount of gas which can be dissolved in water depends on:
- The temperature of the water (colder can absorb more)
- The solubility of the gas, CO2 is more soluble then O2
- The partial pressure of a gas in the air above the water
Henry’s law:
Gas in the alveoli quickly become at equilibrium with the blood gas levels because:
Small exchange distances
Massive surface area
Of the factors in Henry’s law which variable actually changes within the alveoli:
Partial pressure!
Not temp, it stays fairly constant in the blood.
The solubility of a gas is a constant for the gas.
