ch 39

Question 1

what is the bodys natural humidification device

Answer 1

nose

Question 2

what is ISB

Answer 2

Isothermic saturation boundary

Question 3

how does temperture differ above ISB with inspiration and expiration

Answer 3

inspiration: decrease
expiration: increases

Question 4

what outside factors can cause a shift in ISB?

Answer 4

*breathing in cold dry air
*upper airway by pass (trach, endo tube)
*minute ventilation is higher than normal

Question 5

describe body humidity and humidity deficit

Answer 5

body humidity:
*relative humidity @ body temp
*water capacity of 44mg/L @ 37C
*BH=absolute humidity/44X100

humidity deficit
*not fully saturated @37C
*corrected by bodys own humidification system
*HD=44 - absolute humidity

Question 6

what would happen if temp decreased suddenly?

Question 7

indications for humidification

Answer 7

*dry medical gases
*bypass upper airway
*treating bronchospasm caused by cold air

Question 8

clinical signs of inadequate airway humidification

Answer 8

*atelectasis
*dry nonproductive cough
*infection
*increased airway resistance
*increased WOB
*patient complaint of substeral pain & airway bypass
*thick, dehydrated secretions

Question 9

factors affecting humidifier performance: temperature

Answer 9

increase temp of gas
increased water carrying capacity

Question 10

factors affecting humidifier performance: surface area

Answer 10

increased gas/water contact area= increased evaporation

Question 11

factors affecting humidifier performance: time of contact

Answer 11

increased gas/water contact area time= increased evaporation

Question 12

what is the difference b/w active and passive humidifiers

Answer 12

active: adding heat or water or both to device patient interface

passive: recycling exhaled heat & humidity from patient

Question 13

what is an active humidifier

Answer 13

adding heat or water or both to device patient interface

types: bubble, passover, nebulizers of bland aerosol & vapor

Question 14

bubble humidifiers ( what will happen if exceed 4L w/out the bubble)

Answer 14

*dry gas damage
*heat loss
* water loss
*structural damage
*airway irritation
*increased mucus
*ciliary motility reduction
*increased secretion viscosity

Question 15

passover humidifiers: what is the advantage over bubble

Answer 15

*maintains saturation at high flow rates
* adds little or no flow resistance
* do not generate any aerosols

3 types: simple, wick, membrane

Question 16

what is the potential risk of using humidifier

Answer 16

airway burns

Question 17

what can happen if a passover humidifier runs out of water

Question 18

what is passive humidification

Answer 18

HME
recycles captured exhaled heat & moisture
“artifical nose”

Question 19

when do we use the HME?
how does it work?

Answer 19

*use for patients on mechanical ventilation
* capture the heat and moisture from air a patient exhales than using to humidify air they inhale

Question 20

explain dead space? what can cause it

Answer 20

• portion of breathing that doesnt participate in gas exchange (nose, mouth down to terminal bronchioles)
• alveoli that do not participate in gas exchange

Question 21

how much dead space does HME cause

Answer 21

30-90 ml

Question 22

what are the temperatures you can set a heated humidifier to? what can happen if temp is to low or high?

Answer 22

33C- 37C,
prevents complication like drying of the mucosa

Question 23

what liquids can be used for bland aerosol therapy?

Answer 23

• sterile water
  *sterile saline: hypotonic, isotonic, hypertonic

Question 24

indications of bland aerosol therapy

Answer 24

*upper airway edema
* croup
*subglottic edema
*post extubation edema
*post operative management of upper airway
*bypassed airway
*need of sputum specimen

Question 25

hazards/complications for bland aeresol therapy

Answer 25

*wheezing/bronchospasm *infection *over hydration *patient discomfort * caregiver exposure to airborne contagions by sputum/coughing

Question 26

what type of patients can benefit from cool aerosol therapy

Answer 26

*upper airway edema/swelling *bypassed upper airway *sputum induction

Question 27

to set up large volume nebulizer, what equipment do you need

Answer 27

*aerosol mask *face tent *t-tube *trach mask *drainage bag/containor

Question 28

how does condensation pose a risk

Answer 28

* patient/caregiver *block flow of gas through the tube, aspirated water going into the lungs

Question 29

what can cause cross contamination?

Answer 29

*water in circuit can be course of bacterial colonization *minimizing condensation is helpful to reduce risk of colonization *wick-membrane type passover humidifiers prevent formation of bacteria carrying aerosols. change circuit when needed

Question 30

what is used to monitor the temperature of inspired gas received by patients?

Answer 30

hygrometer-thermometer system

Question 31

what is the purpose of mist tents/hoods

Answer 31

used to treat children w/croup *promotes vasoconstriction *reduces edema *diminishes upper away obstruction

Question 32

what are some hazards of mist tents/hoods

Answer 32

*heat retention *CO2 build up (high flow of fresh gas to washout CO2 and heat)

Question 33

hazard of aerosol therapy

Answer 33

*infection *airway reactivity *pulmonary&systemic effects *drug concentration changes *eye irritation *exposure to second hand aerosol drugs

Question 34

problem solving: inadequate mist production

Answer 34

check electrical power supply, carrier gas is flowing through device, amplitude control, couplet chamber

Question 35

problem solving: overhydration

Answer 35

prevention by careful patient selection & monitoring is key

Question 36

explain croup. who can get it? how do we fix it? what is a contraindication for this patient?

Answer 36

*effects young children (6m-3yrs) *narrowing of the airway, swelling trachea * difficult breathing Bland aerosol therapy

Question 37

what is hypertonic saline? why do we use it?

Answer 37

bland aerosol therapy saline liquid used for sputum inductions