Oxygen Delivery

Question 1

What is FiO2?

Answer 1

The fraction of oxygen within inhaled air
-natural air includes 20% oxygen: FiO2 = 0.20
-medical patients are provided with oxygen-enriched air, which is higher than atmospheric FiO2

**accurate FiO2 can not be delivered with nasal canula

Question 2

What are examples of low-flow oxygen systems?

Answer 2

-nasal canula
-simple mask
-non-rebreather
-partial non-rebreather

**varies depending on the delivery device and the patient’s oxygenation needs

Question 3

What are examples of high-flow oxygen systems?

Answer 3

-venturi mask
-aerosol/large volume nebulizer
-ventilators

**deliver fixed concentrations of oxygen, regardless of the inspiratory flow or breathing pattern

Question 4

What is the FiO2 range through a nasal canula

Answer 4

24-44% (1-6 L) - the fraction of oxygen inspired increases by 4% for every additional liter of oxygen flow administered
-Example: 1 L= 24%, 3 L= 32%

Question 5

T/F a nasal canula is able to deliver both low and high concentrations of O2

Answer 5

False- cannot deliver high concentrations, only effective for low concentrations

Question 6

Considerations for nasal canula

Answer 6

-can dry out mucous membranes
-the maximum flow if 5-6 LPM (change devices if patient requires >5 LPM)
-use on patients with adequate tidal volume and normals vitals

Question 7

What is the FiO2 range for a simple mask?

Answer 7

25-60% (6-10 L)

Question 8

Considerations for a simple mask

Answer 8

-tight seal is required for higher oxygen concentrations
-hot and confining
-impractical long-term use
**a minimum of 6 LPM is required for all masks to flush expired CO2 to prevent rebreathing of it

Question 9

which conditions are simple masks used for?

Answer 9

-severe asthma
-pneumonia
-trauma
-severe sepsis

Question 10

What is the fiO2 range fir a non-breather?

Answer 10

80-95% (10-15 L)- delivers the highest possible oxygen concentrations without incubation

Question 11

Considerations for a non-breather

Answer 11

-used when pts have low blood oxygen levels
-used for short-term therapy
-requires a tight seal
-consists of a mask and a reservoir

Question 12

what is the FiO2 range for a partial non-rebreather

Answer 12

35-60% (8-12 L)

Question 13

Considerations for a partial non-rebreather

Answer 13

-looks similar to a non-rebreather mask but it contains a 2-way valve between mask and the reservoir bag
-valves allow expired CO2 to leave the mask
-cannot obtain as high of a blood oxygen concentration since the O2 in the reservoir bag becomes diluted

Question 14

range of FiO2 for venturi mask

Answer 14

24-60% - determined by the color of the venturi device

**an accurate O2 concentration depends on oxygen liter flow and the color of the attached venture device

Question 15

which patients use a venturi mask?

Answer 15

COPD patients

Question 16

range of FiO2 for an aerosol/large volume nebulizer

Answer 16

28-100% (10-15 L)

Question 17

Considerations for an aerosol/large volume nebulizer

Answer 17

-administers large volumes of mist
-indicated for thick secretions
-observe for signs of over-hydration, pulmonary edema, crackles

Question 18

what is an oral pharyngeal airway?

Answer 18

a semirigid tube of plastic or rubber shaped to fit the natural curve of the soft palate and tongue

Question 19

What is a nasal pharyngeal airway?

Answer 19

a soft or rubber tube inserted through one of the nares- follows the wall of the nasopharynx and oropharynx to the base of the tongue

**less likely to stimulate gag reflex

Question 20

What is an endotracheal tube? && what are the different types?

Answer 20

artificial airway inserted into the trachea
-oral endotracheal tube: inserted via the mouth
-nasal endotracheal tube: inserted via the nose

Question 21

What are the 4 reasons to use endotracheal intubation?

Answer 21

1. upper airway obstruction
2. inability to protect the lower airway from aspiration
3. inability to clear secretions from the lower airways
4. need for positive pressure mechanical ventilation

Question 22

What is a trachestomy?

Answer 22

an airway opening that is surgically created directly over the trachea and inserted below the level of the vocal cords

Question 23

what are the modes of ventilation?

Answer 23

-assist control
-synchronized intermittent mandatory ventilation (SIMV)
-continuous positive airway pressure (CPAP)
-positive end-expiratory pressure (PEEP)
-pressure support ventilation (PSV)

Question 24

What is assist control?

Answer 24

a non-weaning mode where the rate and tidal volume are set to deliver a minimum minute ventilation
-pt can generate as many breaths as needed by triggering the ventilator
-with each respiratory effort by the pt, the machine delivers the preset tidal volume

Question 25

What is synchronized intermittent mandatory ventilation (SIMV)?

Answer 25

a weaning mode where the rate and tidal volume are set to deliver a minimum minute ventilation
-pt can breathe spontaneously between ventilator breaths
-each breath depends on the patient’s effort
-good for respiratory muscle exercise

Question 26

What is the main disadvantage os SIMV?

Answer 26

it increases the work of breathing so if the patient shows signs of fatigue they may need to switch to another mode

Question 27

What is continuous positive airway pressure (CPAP)?

Answer 27

A weaning and spontaneous mode of ventilation that maintains positive pressure continuously in the airways
-pressure support is added to augment patient’s tidal volume

Question 28

What is positive end-expiratory pressure (PEEP)

Answer 28

Positive pressure that is applied at the end of expiration during ventilation
-ensures that alveoli don’t collapse

Question 29

What is pressure support ventilation (PSV)?

Answer 29

Once the patient triggers the ventilator, a preset positive pressure is delivered
-applies to spontaneous breaths only and the patient controls the respiratory rate and inspiratory time
-it helps to decrease the work of breathing and allows for more patient comfort

Question 30

What is the disadvantage of PSV?

Answer 30

there is no guaranteed ventilation- if the pt stops breathing for any reason, then ventilation ceases and alarms will sound