Chapter # 3, Lung Volume

Question 1

Direct Spirometer measures all volumes and capacities except:

Answer 1

• RV
• FRC
• TLC.
• (It’s called Directed Spirometry because it direct measures indivuals exhale gases.

Question 2

Lung Volume Testing is also called:

Answer 2

Indirect spirometry

Question 3

There are two types of Indirect Spirometer Testing technique:

Answer 3

• Gas Dillution (Nitrogen washout and He Dilution)
• Body Plethysmography (Body Box)

Question 4

Indirect Spirometry is performed to measure?

Answer 4

FRC Volume

Question 5

Which Lung Volume is the most reproducible and provides a consistent baseline for measurements?

Answer 5

FRC

Question 6

Gas Dilution techniques operates on a principle similar to:

Answer 6

Boyle’s Law (P1 V1 = P2 V2)

Question 7

All opertates on a principle similar to Boyle’s Law (P1 V1 = P2 V2), which states the volume of gas varies inversely whith its pressure.

Answer 7

Gas Dilution Technique

Question 8

How much percent of Nitrogen is in the lung?

Answer 8

78%

When people breath normal they breath about 78% of N2 which is normally in the air.

Question 9

When a patient is performing Open circuit, multiple-Breath Nitrogen WashOut, they should be able to wash out all the Nitrogen from the lungs in about …?

Answer 9

3-4 minutes

Question 10

Nitrogen Wash Out Test must be carefully initiated from?

Answer 10

FRC baseline levels

Question 11

Nitrogen Washout Test is succefully complete when:

Answer 11

N2 level decrease to become

<1.5% for at least 3 successive breaths

Question 12

This is?

Answer 12

Nitrogen Washout leack

It happen when patient breath small amout of air while his treatment allowing N2 inhalation

Question 13

Nitrogen Washout criteria for acceptability

Answer 13

• The washout tracing should indicate a continually falling concentration of alveolar N2.
• The test should continued until the N2 concentration falls to <1.5% for 3 concecutive breaths.
• Washout should be appropriate for the subject tested (Healthy subjects should washout their N2 in 3-4 minutes)
• The washout time should be reported. (Falure to washout N2 whithin 7 minutes should be noted)
• Multiple measurements should agree within 10%
• At least 15 minutes of room-air breathing should elapse between repeated trials, >1 hours for patients with severe obstructive or bolluos disease

Question 14

Hilium Dilution is a open or close circuit?

Answer 14

Close

Question 15

He Dilution Procedure:

Answer 15

• Spirometer is fillid with a known volume of air with added oxygen 25% to 30%
• A volume of He is added approximately 10%.

Question 16

Criteria for acceptabibily of Helium Dilution Procedure

Answer 16

1. Spirometer tracing should show no leacks ( which would cause an overstimation of FRC)
2. Test is successfully completed when He reading change by less than 0.02% in 30 seconds or until 10 munutes elapsed.
3. Multiple measurement of FRC should agree within 10%
4. The Average of acceptable multiple measurements should be reported.

Question 17

The problem with Gas Dilution Technique is :

Answer 17

Can only measure lung volume in comunication with conducting airways!!!

Question 18

On patient with Air trapping Gas Dilution Technique will provide not a good measure, Why?

Answer 18

Becauce we can’t measure the gas that the patient can not exhale as a consecuence it will reduce the side of FRC (Understimate)

That’s why Gas Dilution Technique can only measure lung volume in communication with conducting airway

Question 19

Which Test would you recomend to get the most acurate result on a severe Emphysema patient to measure its FRC? why?

Answer 19

Body Box Technique, because Body Box has the ability to measure lung volume even those with Air Trapping, unlike Gas Dilution Technique that just measure gas volume in communication with Airways

Question 20

True Or False

In Patients with Air trapping, Plethysmography lung volume are usually larger to those measures with gas dilution technique

Answer 20

True

Question 21

True or False

Unlike Gas Dilution Technique, Body box include both air in commuication with open airway as well as air trapped within noncommunicating thoracic comparments…

Answer 21

True

Question 22

BB, criteria for acceptability

Answer 22

1. Patient maneuver shows a closed loop without drift.
2. Tracing does not go off the screen.
3. Panting is 0.5 - 1 Hz.
4. Tangents should be within 10%.
5. At least 3FRCpleth values shloud agree within 5% and the mean reported.

Question 23

Is require for the determination of RV, FRC, and TLC

Answer 23

Indirect Spirometry or Lung Volume Testing

Question 24

Used to measure all volume that can be exhaled

Answer 24

Direct Spirometry

Direct Spirometry can only measures volumes that can be exhaled, unlike Lung Volume testing that measures all

Question 25

The Volume measured with Body Box is refered as:

Answer 25

Thoracic Gas Volume

(TGV) (VTG)

Question 26

When Hellium Dilution technique is successfully complete?

Answer 26

when Helium reading change by less than 0.02% in 30 seconds or until 10 minutes has elapsed.