Like this study set? Create a free account to save it.

Sign up for an account

Already have a Quizlet account? .

Create an account

Identify relationships and general principles about gas exchange as it relates to the respiratory system.


- The mechanical movement of air into and out of the airways in a cycle fashion
- Alveolar ventilation-ventilation of alveoli that are being perfused and adequate gas exchange is taking place
- Dead Space Ventilation-volume of gas that is ventilated, but not physiologically effective (Anotomic, Alveolar, and Physiologic)

Anatomic Dead Space

- The volume of air contained in the pulmonary conducting system that is not involved in gas exchange
- Rule of Thumb-1ml/lb body weight
- Abbreviated as VDanat

Alveolar Dead Space

- The ventilation of an alveoli that is not being perfused (the passing of blood or fluid through a vascular bed) via the pulmonary capillary bed therefore has no gas exchange
- If significant it indicates a pulmonary pathological disease
- Abbreviated VDalv

Physiologic Dead Space

- The portion of inhaled air that does not take part in pulmonary gas exchange
- Combination of anatomic and alveolar dead space
- Abbreviated VDphy

Clinical Terms Associated with Ventilation

- Normal Ventilation-the amount of minute ventilation (also referred to as respiratory rate or tidal volume) to provide adequate alveolar ventilation and fulfill the body's gas exchange needs
- Hypoventilation-the state of impaired breathing where the alveoli are inadequately ventilated to fulfill the body's gas exchange needs
- Hyperventilation-an over-aeration of the alveoli beyond gas exchange needs (may be voluntary or involuntary)

Volumes and Capacities

- Vital Capacity (VC)-the amount of air that is maximally exhaled after a maximal inhalation
- Residual Volume (RV)-the amount of air remaining in the lungs at the end of a maximal exhalation
- Total Lung Capacity (TLC)-the amount of air remaining in the lungs after a maximal inhalation
- Functional Residual Capacity (FRC)-the amount of air remaining in the lungs at the end of a normal resting exhalation


- Refers to the molecular gas exchange of oxygen and carbon dioxide
- External Respiration-exchange of gases between the alveoli and the pulmonary capillaries
- Internal Respiration-the exchange of gases between systemic capillaries and tissue cells

Pulmonary Blood Volume

- The volume of blood between the beginning of the pulmonary artery and the end of the pulmonary veins
About 900 to 1000ml (healthy adult)
- 30% (p) arteries
- 10% (p) capillaries
- 60% (p) veins

Pulmonary Capillary Blood Volume

- The volume of blood in the capillary bed at any given moment
- Contains about 100ml at any given time (healthy adult)
- At rest, complete oxidation of the RBC takes 0.75 seconds
- During exercise oxidation of the RBC takes 0.35 seconds
- About 95% of the diffusion of O2 takes place before the blood has passed halfway along the pulmonary capillaries

Pulmonary Blood Flow

- 100ml/sec
Effected by gravity
- Supine or Prone-close to uniform blood flow
- Erect Position-non uniform blood flow

Pulmonary Vessels

- In general are shorter, thinner, and more distensible and contain less smooth muscle than systemic blood vessels
- Hold a larger volume in relation to their systemic counterparts, due to the smaller amount of muscle tissue

Pulmonary Artery Pressures

- Systolic-25mmHg
- Diastolic-8mmHg
- Reflect right ventricular systolic pressures
- Hypoxia is a potent constrictor

Please allow access to your computer’s microphone to use Voice Recording.

Having trouble? Click here for help.

We can’t access your microphone!

Click the icon above to update your browser permissions and try again


Reload the page to try again!


Press Cmd-0 to reset your zoom

Press Ctrl-0 to reset your zoom

It looks like your browser might be zoomed in or out. Your browser needs to be zoomed to a normal size to record audio.

Please upgrade Flash or install Chrome
to use Voice Recording.

For more help, see our troubleshooting page.

Your microphone is muted

For help fixing this issue, see this FAQ.

Star this term

You can study starred terms together

Voice Recording