Term
| What is phsyiologic dead space? |
|
Definition
| anatomic deadspace + alveolar deadspace |
|
|
Term
| What is the average amount of anatomic dead space? |
|
Definition
|
|
Term
| Average total lung capacity? |
|
Definition
|
|
Term
|
Definition
a normal inspiration & expiration
usually about 500 mL |
|
|
Term
| Inspiratory reserve volume |
|
Definition
| amount that can be inhaled beyond a normal inhalation |
|
|
Term
| Expiratory reserve volume |
|
Definition
| amount that can be forcefully exhaled beyond a normal exhalation |
|
|
Term
|
Definition
amount of air that remains in the lungs even after a forced max. exhalation
about 1 L |
|
|
Term
| Functional residual capacity |
|
Definition
| expiratory reserve volume & residual volume |
|
|
Term
|
Definition
| max inhalation after a normal exhalation |
|
|
Term
|
Definition
| inspiratory reserve volume, tidal volume, and expiratory reserve volume |
|
|
Term
| Methods of measuring lung volumes |
|
Definition
pneumotachometer (can't measure FRC or TLC)
spirometer (can't measure FRC or TLC)
He dilution technique
body plethysmography |
|
|
Term
|
Definition
known vol. of He in spirometer
patient turned to system at FRC
patient breathes until He concentration is at equilibrium between lungs and spirometer
FRC calculated |
|
|
Term
|
Definition
known vol. in box
change pressure in airway
vol. of gas in thorax can be calculated with boyle's law |
|
|
Term
|
Definition
|
|
Term
|
Definition
ventilation without perfusion
anatomical
alveolar
physiologic |
|
|
Term
| Fowler's Method of measuring anatomic dead space |
|
Definition
subject breathes in 100% O2
Nitrogen concentration rises as deadspace gas is washed out
uniform plateau of pure alveolar gas |
|
|
Term
| Bohr Method of measuring dead space |
|
Definition
calculate dead space using the bohr equation
Vol. deadspace/tidal vol. = (PaCO2-PECO2)/PaCO2 |
|
|
Term
| Alveolar ventilation equation |
|
Definition
|
|
Term
|
Definition
high CO2 in the blood
PaCO2 of 45 or greater |
|
|
Term
| Distribution of ventilation |
|
Definition
Ventilation is preferential based on gravity.
In standing patients, base of lungs is favored |
|
|
