Term
|
Definition
| inspired air that does not reach the alveoli |
|
|
Term
| What are the three types of dead space? |
|
Definition
* 1) Anatomic
* 2) Alveolar
* 3) Physiologic |
|
|
Term
|
Definition
| the amount of air in the conducting airways |
|
|
Term
| The amount of anatomic dead space is equal to what? |
|
Definition
|
|
Term
| During inspiration, what happens to the “fresh gas" and “non-fresh gas"? |
|
Definition
| They are mixed within the in the conducting airways. |
|
|
Term
| Minute Alveolar Ventilation |
|
Definition
| MV= (TV - deadspace) x RR |
|
|
Term
| What impacts minute alveolar ventilation? |
|
Definition
1) Depth of volume
2) respiratory rate |
|
|
Term
| Which is more effective at increasing minute ventilation (decreasing PaCO2), increasing tidal volume ore respiratory rate? |
|
Definition
|
|
Term
|
Definition
| No spontaneous ventilation |
|
|
Term
|
Definition
| Normal spontaneous breathing |
|
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Term
|
Definition
| Increased volume but unchanged rate |
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Term
|
Definition
| Short episodes of rapid uniform deep inspiration followed by 10-30 seconds of apnea |
|
|
Term
|
Definition
| Increase alveolar ventilation (either rate, volume, or both) causing PaCO2 to decrease. |
|
|
Term
|
Definition
| Decrease in alveolar ventilation (either due to rate, volume, or both) causing a rise in PaCO2. |
|
|
Term
|
Definition
| 10-30 seconds of apnea then very fast volume and rates, then gradual decline and apnea. |
|
|
Term
|
Definition
| Increased depth and rate (diabetic ketoacidosis) |
|
|
Term
|
Definition
| Inability to breath unless in the upright position |
|
|
Term
|
Definition
|
|
Term
|
Definition
| Difficulty breathing (conscious awareness of). Dyspnea is a subjective component used to describe “the feeling that you are not getting enough air”. |
|
|
Term
|
Definition
| defined as “alveoli that are ventilated but not perfused” |
|
|
Term
| Can you calculate alveolar dead space? |
|
Definition
No
-Here is what the powerpoint said:
The amount of dead space is “difficult to calculate” and “cannot be calculated because it is unpredictable” |
|
|
Term
|
Definition
| Sum of anatomical and alveolar dead space |
|
|
Term
|
Definition
| "Measures the presence of CO2 (patency) and quantifying CO2" |
|
|
Term
| At what point in the respiratory cycle is EtCO2 measured? (inspiration or expiration) |
|
Definition
| Expiration ("This point best represents CO2 in the alveoli or lower airways.") |
|
|
Term
| Does EtCO2 and PaCO2 correlate in healthy individuals? |
|
Definition
|
|
Term
| Does EtCO2 mix with air in the conducting pathways? |
|
Definition
|
|
Term
|
Definition
| Volume of air inspired or expired with each normal breath (500ml) |
|
|
Term
| Inspiratory Reserve Volume |
|
Definition
| Extra volume of air that can be inspired over and above the normal tidal volume (3000ml) |
|
|
Term
| Expiratory Reserve Volume |
|
Definition
| Extra volume of air that can be forcefully expired after a normal exhaled tidal volume (1100ml) |
|
|
Term
|
Definition
| Is a means to measure various volumes in the lungs. |
|
|
Term
|
Definition
| Volume of air that remains after forceful expiration (1200ml) |
|
|
Term
| Vital Capacity (equation) |
|
Definition
IRV + TV + ERV (4800ml)
Inspiratory Reserve Volume + Tidal Volume + Expiratory Reserve Volume |
|
|
Term
| Vital Capacity (explained in words) |
|
Definition
| It is the amount of volume that can be expelled from the lungs after first taking a very deep breath (4800ml) |
|
|
Term
| Another name for Vital Capacity |
|
Definition
| Sometimes called the Forced Vital Capacity (FVC) |
|
|
Term
| Functional Residual Capacity (equation) |
|
Definition
ERV + RV
expiratory reserve volume + residual volume |
|
|
Term
| Functional Residual Capacity (explained in words) |
|
Definition
| Amount of volume left in the lungs after normal expiration |
|
|
Term
| Why is the functional residual capacity important in anesthesia? |
|
Definition
| b/c it is the amount of volume (and is located in the area of the lungs) where much of the air exchange is occurring |
|
|
Term
| What can reduce the functional residual capacity? |
|
Definition
Displacement of the diaphragm and pushing abdominal contents upward in all of the following situations:
-supine position
-trendelendburg position
-obesity
-compression on the abdomen
-belly insufflation |
|
|
Term
|
Definition
TV + IRV
Tidal Volume + Inspiratory Reserve Volume |
|
|
Term
|
Definition
| measure the amount of forced expired volume (FEV) in1 second to the total Forced Vital Capacity (FVC), this ratio gives us a percentage |
|
|
Term
| What is a normal FEV-1/FVC? |
|
Definition
| 80% (meaning that you can forcibly exhale 80% of FVC in 1 second) |
|
|
Term
| What sex are all of the standard lung volumes based on? |
|
Definition
| Males ("in women the volumes are appoximately 20% less) |
|
|
Term
| Functional Residual Capacity (2nd definition in words found in the lecture) |
|
Definition
| also defined as the volume in which inward lung elastic recoil= the outward chest wall recoil |
|
|
Term
| What 5 Factors impact functional residual capacity? |
|
Definition
1. Body habitus:
* FRC is directly proportional to height. Obesity greatly decreases FRC (loss of chest compliance)
2. Sex:
FRC is > in males compared to females
3. Posture
FRC decreases as pts are moved from upright to supine or prone position due to decreased lung compliance from abdominal contents pushing upward against the diaphragm
* Greatest change occurs between 0-60 degrees, with no additional change in the head down position of up to 30 degrees (?)
4. Lung Disease:
decreases FRC due to decreased of the lung, chest, or both.
5. Diaphragmatic Tone:
In anesthesia, "muscle relaxants stop the diaphragm from working”. |
|
|
Term
| What can measure basic lung volumes? |
|
Definition
|
|
Term
| What gas law does plethysmography use? |
|
Definition
|
|
Term
| Plethmysmography, how does it work? |
|
Definition
* Test subject is placed in a sealed chamber with a mouthpiece
* At the end of normal expiration, the mouthpiece is closed
* Pt makes an inspiratory effort
* As pt tries to inhale, the lungs expand, decreasing lung pressure and increasing lung volume
* This causes a pressure increase in the chamber, since it is a closed system, and the volume of the body compartment has increased
* Temperature and pressure remain constant, volume changes |
|
|
Term
|
Definition
the volume at which the small non-cartilaginous airways close during exhalation (these airways rely on volume to keep them open)
-"alveoli in dependent areas will continue to be perfused but not ventilated!" |
|
|
Term
| What is used to measure closing capacity? |
|
Definition
| A tracer, like Xenon gas. |
|
|
Term
| Is closing capacity bigger or smaller than FRC? |
|
Definition
| Smaller, but it rises with age. |
|
|
Term
| Why does arterial O2 tension decrease with age? |
|
Definition
| Because closing capacity rises steadily with age. |
|
|
Term
| By age 44, at what point are CC and FRC equal? |
|
Definition
|
|
Term
| By age 66, at what point are CC and FRC equal? |
|
Definition
|
|
Term
| Is Functional Residual Capacity affected by age or position? |
|
Definition
|
|
Term
| Is Closing Capacity affected by age or position? |
|
Definition
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