Exam 3 Flashcards
Tidal Volume (TV) amount
Males: 600 mL
Females: 500 mL
Total Lung Capacity (TLC) amount
Males: 6,000 mL
Females: 4,200 mL
Inspiratory Reserve Volume (IRV) amount
Males: 3,000 mL
Females: 1,900 mL
Expiratory Reserve Volume (ERV) amount
Males: 1,200 mL
Females: 800 mL
Residual Volume (RV) amount
Males: 1,200 mL
Females: 1,000 mL
Ventilation Rate
1500 mL/min
The 3 main functions of the lungs
1) O2 & CO2 homeostasis
2) Maintain acid-base balance (pH)
3) Filters, metabolizes toxic substrates
The ability of the lung to have adequate exchange of gases is due to:
- Ability of the lungs to create negative pressure
- The ability of the lungs to expand and fill alveoli
- The ability to receive adequate cardiac output (especially the R side of the heart and Pulmonary Artery)
- The ability for oxygen to attach to hemoglobin
- The ability for oxygen to diffuse at the cellular level
Slow controlled breathing is called what?
Laminar breathing which has less resistance b/c the breathing is slow and not hitting the walls as much (less resistance)
Inhalation stops when?
When the outward pull of the respiratory muscles equals the pull or elastic recoil of the lung parenchyma (tissue)
What type of process is exhalation?
It is a passive process that happens during the relaxation of the inspiratory muscles because the alveolar pressure is greater than the atomspheric pressure.
Describe the process of exhalation when it is active.
This happens during coughing and exercise.
The abdominal muscles contract which pushes the diaphragm cephalic which decreases thoracic volume causing increased intrathoracic pressure and then air is actively expelled
Lung Compliance & Chest wall compliance
How easy it is to inflate the lungs
Low compliance means the lungs are stiff and hard to expand
Same thing but related to the chest wall
Atelectasis
Deflated or under inflated alveoli
Surfactant(produced by Type II cells) helps prevent alveolar collapse
You can auscultate a popping noise
Poiseuille’s Law
Radius greatly affects airway resistance
Very wide radius will have low resistance
narrow radius will have high resistance
The effect of air distribution with ventilation
Since the alveoli at the top region of the lungs are more expanded and filled with air, there is more movement in expansion of the alveoli in the middle and lower regions.
When we exercise, we get higher lung volumes and distributes the air more equally through out the lungs
Zones of Perfusion & Ventilation or Zones of West
Zone 1
Zone 1 = Aveoli > Arteries > Veins
No blood flow
Pressure in the alveolus is greater than the pulmonary capillary pressure due to air rising
Abnormal Condition
It is generally only observed when a person is ventilated with positive pressure. In these circumstances, blood vessels can become completely collapsed by alveolar pressure and blood does not flow through these regions. They become alveolar dead space.
The zones of the lung divide the lung into three vertical regions, based upon the relationship between the pressure in the alveoli (PA), in the arteries (Pa), and the veins (Pv):
Zone 1: Aveoli > Arteries > Veins (this provides good ventilation but not perfusion)
Zone 2: Arteries > Alveoli > Veins (mid and upper lungs when seated- this provides good ventilation and perfusion)
Zone 3: Arteries > Veins > Alveoli (lower lung when seated- capillary pressure essentially smushes the alveoli- good blood supply, poor ventilation)
Zones of Perfusion & Ventilation or Zones of West
Zone 2
Zone 2 = Arteries > Alveoli > Veins (mid & lower lungs when seated)
Intermitten blood flow during systole
Limited blood flow during diastole
(good ventilation and perfusion)
Zone 2 is the part of the lungs about 3 cm above the heart. In this region blood flows in pulses. At first there is no flow because of obstruction at the venous end of the capillary bed. Pressure from the arterial side builds up until it exceeds alveolar pressure and flow resumes. This dissipates the capillary pressure and returns to the start of the cycle.
Zones of Perfusion & Ventilation or Zones of West
Zone 3
Zone 3: Arteries > Veins > Alveoli (lower lung when seated- capillary pressure essentially smushes the alveoli- good blood supply, poor ventilation)
Continuous blood flow
Zone 3 comprises the majority of the lungs in health. There is no external resistance to blood flow and blood flow is continuous throughout the cardiac cycle.
Alveolar ventilation in reference to ventilation and perfusion matching
4 L/m
Cardiac Out in reference to ventilation and perfusion matching
5 L/m
Ventilation/Perfusion
V/Q = 0.8 with exercise it can be 1.7
greater ability to take in O2 and send it to the blood
Fick’s Law
Rate of transfer of a gas is proportional to:
- Tissue area (how many alveoli are present and healthy)
- Difference in partial pressure (venous oxygen content and alveolar oxygen content)
Rate of transfer of a gas is inversely proportional to:
- Tissue thickness
Diffusion of Gases is dependent upon…
- The volume of blood flow
- The amount of RBC (anemia)
- Structure of the hemoglobin
CO2 is a byproduct of what energy cycle?
Kerb’s Cycle
Work of breathing depends upon what 3 things?
- Thoracic Cage and Lung Compliance
- Muscular work
- Airway resistance work
It take 3-5% of total energy expenditure to breathe in a normal person
Work of breathing depends upon what 3 things?
- Thoracic Cage and Lung Compliance
- Muscular work
- Airway resistance work
It take 3-5% of total energy expenditure to breathe in a normal person
Prevention of Infections in the lungs and nose are due to
Mucociliary Elevators that are in the bronchi, bronchioles, and nose
There are 2 main parts:
Goblet cells to produce mucus
Cilia that beat- facilitates movement of secretions
Pulmonary Function Tests are use for:
- To measure the function of the respirator muscles
- to measure the health/function of airways
- To help classify diseases
Functional Vital Capacity (IRV + TV + ERV)
Men: 4,800 m/L
Women: 3,200 m/L
