Humidity And Aerosol

Question 1

What is humidity

Answer 1

Water in the gaseous state

Question 2

What is the maximum amount of water vapor present in a gas

Answer 2

44 mg/L absolute humidity

47 mmHg partial pressure

Question 3

Humidity therapy

Actual weight of water vapor contained in a given volume of gas is expressed in

Answer 3

Mg/L or g/cu.m.

Question 4

At body temperature, what is our absolute humidity

Answer 4

44 mg/L

Question 5

Absolute humidity =

Answer 5

RH X capacity (must be given : except know at 37 degrees Celsius absolute humidity is 44 mg/L)

Question 6

How is. RH (relative humidity) expressed and obtained

Answer 6

Expressed as a percentage, obtained with a hygrometer

Question 7

Formula for RH

Answer 7

Absolute humidity/ capacity

Question 8

Partial pressure of water vapor at 37 degrees C is

Answer 8

47 mmHg (torr)

Question 9

What is humidity deficit

Answer 9

The physiological term that refers to the difference between the inspired gas’s water content and the water content of a gas at body temperature and pressure.

Question 10

Formula for humidity deficit

Answer 10

Body humidity (44mg/L) - actual (absolute humidity)

Question 11

Causes of humidity deficit

Answer 11

Retention of secretions (increased Raw)

Airway mucus plugging

Obstruction of the airway

Infection

Question 12

What do less that body humidity secretions tend to do

Answer 12

Dry, making them thicker and more difficult to mobilize

Question 13

Humidity therapy primary indication

Answer 13

To humidify dry inspired gases

To overcome the humidity deficit when the upper airway is bypassed

Question 14

Factors influencing humidity therapy

Answer 14

Temperature
Surface area
Contact time

Question 15

How often should heated humidifiers be replaced

Answer 15

Every 24 hours

Question 16

How much humidity are heated humidifiers capable of delivering

Answer 16

100 % body humidity

Question 17

Are nosocomial infections caused by humidifiers

Answer 17

No, because molecular water is too small to carry bacteria

Question 18

Bubble humidifier pop offs at

Answer 18

2 psi, 40 lpm

Question 19

How much humidity can a bubble humidifier deliver

Answer 19

35-40% body humidity

Question 20

What happens if humidifier is ran dry

Answer 20

The thermostat automatically shuts off

Question 21

Heat and moisture exchanger

Answer 21

Under ideal conditions, the HME can produce 70-90% body humidity

Question 22

What should you do if patients secretions begin to thicken while using the HME

Answer 22

The HME should be changed to a heated humidifier

Question 23

Contraindications of heat and moisture exchanger

Answer 23

Thick copious / bloody secretions

Increased Raw

Low exhaled Vt

Body temp < 32 degrees C

High minute volume

During in line medicated nebulizer treatments

Question 24

Troubleshooting humidity therapy

If secretions are becoming thicker and harder to suction you should

Answer 24

Add heater

Replace humidifier (especially HME ) with conventional heated humidifier.

Question 25

How often should the humidifier be changed

Answer 25

Every 24 hours

Question 26

Indications for aerosol therapy

Answer 26

Upper airway edema Deliver medications Post extubation edema Post op management of upper airway Bypassed upper airway Sputum induction

Question 27

Contraindications of aerosol therapy

Answer 27

Bronchoconstriction History of airway hyperresponsiveness

Question 28

Hazards of aerosol therapy

Answer 28

Wheezing or bronchospasms Bronchoconstriction when artificial airway used Infection Overhydration Patient discomfort Swelling of dried retained secretions Exposure to airborne pathogens

Question 29

Aerosol face mask delivers

Answer 29

21-100% o2 with flow rates of 8-15 lpm

Question 30

Face tent delivers

Answer 30

21-40% with flow rates of 8-15 lpm

Question 31

Tracheostomy collar delivers

Answer 31

35-60% O2 with flowrate of 8-115 lpm Mist should be visible at all times. Even during inspiration to ensure adequate flowrates

Question 32

T-pieces (Briggs adaptors) deliver

Answer 32

21-40% O2 with flowrates at 8-15lpm A 50 - ml reservoir (6 in.) should always be attached to the distal end of the T-piece, otherwise FiO2 will be reduced Mist should be visible at all times

Question 33

Tents deliver

Answer 33

21-50% o2 with flowrates of 8-15 lpm

Question 34

Large volume nebulizers working principle

Answer 34

Bernoulli (uses capillary tube (Venturi, Pitot))

Question 35

Large volume nebulizer aerosol size

Answer 35

Nebulizers produce about 50% of their particles in the 0.5 to 3 ug size range

Question 36

Small volume nebulizer ideal breathing pattern

Answer 36

Tidal breathing through mouth with occasional slow, deep inspirations through the mouth. Breath hold (5-10 seconds) slow passive expiration

Question 37

How long should you shake MDI for

Answer 37

5-10 seconds then discharge one dose if inhaler hasn’t been used in over 24 hours

Question 38

How do you inhale MDI.

Answer 38

Begin to breathe in slowly through open mouth while actuating inhaler. Inspiration should take three to four seconds

Question 39

Ultrasonic nebulizer signal frequency determines

Answer 39

The particle size

Question 40

What does the signal amplitude determine on an ultrasonic nebulizer (USN)

Answer 40

Amount of mist Couplant usually contains tap water 90% of the aerosol particles produced fall within the 0.5 to 3.0 ug range.

Question 41

Aerosol therapy trouble shooting If an aerosol producing device (nebulizer) is producing very little mist what should you do

Answer 41

Check the nebulizer jet for clogs Check the capillary tube and/or the filter on the capillary tube for clogs

Question 42

How often should heated nebulizers be replaced and why

Answer 42

Every 12-24 hours because they are. The greatest source of delivery of contaminated moisture to the patients. Pseudomonas species are the most common contaminant

Question 43

Aerosol therapy trouble shooting Keeping water drained out of the aerosol tubing will prevent

Answer 43

Increasing the delivered FiO2 Decreased the total gas flow to the patient Decrease aerosol output Never drain accumulated water in the aerosol tubing back into nebulizer.