Respiratory Therapy

Question 1

Why do you always need to be bagging when you’re using an ambubag?

Answer 1

There is a valve that prevents the bag from sucking the breath you just gave back after you release the squeeze. That valve remains closed whenever it’s not being squeezed, so no blow-by, PEEP, or CPAP can happen through an ambubag.

Question 2

True or false: if you see that your ambubag doesn’t have it’s manometers, then you need to get a new bag because that bag won’t give breaths.

Answer 2

False

The ambubag can give breaths without its manometers, you just won’t know what the PEEP and PIP are. To make sure you’re giving appropriate breaths, look for chest rise and listen for a leak. It’s nice to have the manometers but not strictly necessary.

Question 3

True or false: ambubags need to be connected to the wall to give breaths.

Answer 3

False

An ambubag that is not connected to the wall will simply give room air that is aspirated from where the wall oxygen would connect. It won’t be supplemental oxygen, but if your patient is apneic then you can help them breathe.

Question 4

Why should you not squeeze all of the air out of a flow-inflating bag when you’re giving breaths?

Answer 4

The residual air is what allows you to be able to squeeze a breath out of the bag. If you completely deflate it then you will have to wait for the oxygen to fill it up, which is just time that you’re not giving breaths.

Question 5

What are the three sizes of masks for ventilation?

Answer 5

Newborn, pediatric, and adult

Question 6

What amount of flow is needed to inflate a flow-inflating bag?

Answer 6

It depends on the size of the bag. A small, newborn bag only needs 8 LPM. A large, adult bag needs 15 LPM.

Question 7

What is one advantage to a flow-inflating bags?

Answer 7

The bag will only inflate if you have a seal on the patient’s face, so you will know if you aren’t maintaining a seal.

Question 8

What is one disadvantage to flow-inflating bags?

Answer 8

There is no pop-off valve like on ambubags, so you can actually hurt the lungs by giving high-pressure breaths.

Question 9

What’s the name of the ventilation that’s given to newborns (as in the machine that gives it)?

Answer 9

T-piece resuscitation

Question 10

One difference to T-piece resuscitation is ________________.

Answer 10

that lung compliance cannot be felt (like it can when squeezing a bag) so if the patient has noncompliant lungs then your normal PIP might hurt them without you knowing

Question 11

In LFNC, how does increasing the LPM affect the FiO2?

Answer 11

For every 1 LPM increase, the FiO2 increases by 4%. So 1 LPM = 25% and 6 LPM = 45%.

Question 12

What are CNC (conventional nasal cannula) and RNC (reservoir nasal cannula)?

Answer 12

• CNC is when NC comes from the wall and has only tubing between wall and nose.
• RNC is when NC comes from the wall but has a reserve of some kind in the tubing. This can look like a ball on the tubing or a rectangle beneath the nasal piece. The reserve allows people to breathe more O2 at the same flow rate.

Question 13

LFNC can go to what LPM?

Answer 13

1-6 LPM

Question 14

What is the conversion of HFNC flow to PEEP?

Answer 14

Every 10 LPM = 0.7 cm H2O PEEP

So 60 LPM HFNC = 4.2 cm H2O PEEP

Question 15

Why is higher flow from NC helpful?

Answer 15

There is always a resistance to inflow in the nose because of exhalation. In respiratory distress, the force of exhalation increases because of airway congestion. High flow overcomes this resistance.

Question 16

In an air blender, air comes in a _________ tube and oxygen comes in a __________ tube.

Answer 16

yellow; green

Question 17

What are contraindications to BIPAP?

Answer 17

• Inability to trigger a breath (e.g., drug overdose, neurologic injury)
• Inability to protect airway (e.g., AMS, airway obstruction)
• Vomiting
• Excessive secretions
• Recent head and neck surgery

Question 18

What are the four types of NIPPV?

Answer 18

• Helmet
• Full face mask (covers mouth, nose, and eyes)
• Partial face mask (covers mouth and nose)
• Nasal mask

The nasal mask is the only one in which people can take oral medicines, but it can’t go to as high of pressures as the others.

Question 19

What is EPAP?

Answer 19

Expiratory Positive Airway Pressure

Also called CPAP or PEEP.

Question 20

What is BiPAP?

Answer 20

It is a type of NIPPV in which there is breath pressure (IPAP or Inspiratory Positive Airway Pressure) on top of continuous baseline pressure (CPAP aka EPAP).

There are timed and spontaneous modes. In the spontaneous mode, patients trigger their own breaths. In the timed mode, you set a rate.

Question 21

What parameters do you need to set in BiPAP?

Answer 21

• EPAP/CPAP/PEEP: typical values 5-8 cm H2O
• IPAP: typical values ~16 cm H2O
• Backup rate (if timed): typically 8-12
• FiO2: 21%-100%
• Time of breath
• Risetime

Question 22

What is AVAPS?

Answer 22

Adaptive Volume Assured Pressure Support

This is a mode of BiPAP that adjusts inspiratory pressure (IPAP) to give a stable volume. It is essentially like volume control for BiPAP.

You might consider this if you’re having trouble controlling ventilation in a person on BiPAP.

Question 23

Describe the path of the phrenic nerve.

Answer 23

It originates from C3-C5, passes anterior to the anterior scalene muscle, dives into the thorax between the lung apices and the large vessels from the top of the hear, and passes between the heart and lungs in the mediastinum.

Question 24

What are the ranges of O2 delivery for a simple mask?

Answer 24

FiO2: up to 60%
LPM: 6-10 LPM

Question 25

How can you tell a non-rebreather mask from a simple mask across the room?

Answer 25

A non-rebreather mask has to have an oxygen reservoir because the unidirectional valves will not let air back in, so you will see a bag on a non-rebreather.

A simple mask has perforations in the sides so air can go in and out so it does not need a bag.

Question 26

What are the ranges of O2 delivery for a non-rebreather mask?

Answer 26

FiO2: up to 90%
LPM: 10-12 LPM

Question 27

If a child is not oxygenating well despite increases in supplemental oxygen, what things should you think about to troubleshoot it?

Answer 27

• Is the O2 tubing kinked?
• Has the child been suctioned?
• Do we need to adjust them to open their airway?
• Is the O2 connected to a source and is that source full?
• Is the pulse-ox malfunctioning (e.g., bad sensor, nail polish on the finger, BP cuff inflating, sensor coming off)?

Question 28

Bag-masks require a minimum rate of __________ in order for the oxygen reservoir to continue to be filled up.

Answer 28

10-15 LPM

Question 29

How can you tell if your bag-mask is sized correctly for the patient?

Answer 29

The mask should extend from the bridge of their nose to the cleft of their chin.

Question 30

To increase ventilation in BiPAP, you need to increase the RR or ___________.

Answer 30

driving pressure, which is the inspiratory pressure minus the PEEP

If you have the standard 10/5 settings you could do 12/5, for instance.

Question 31

What is the max FiO2 through LFNC?

Answer 31

~44%

Question 32

What is an oxymizer?

Answer 32

A nasal cannula supplemental O2 with a hard circular reservoir

It allows for a steady flow of O2 with bolus of O2 from the reservoir as well.

Question 33

You should limit plateau pressures to ___________.

Answer 33

< 30 cm H2O (though higher can be delivered if someone has a stiff chest wall or is morbidly obese)

Question 34

In lung-protective ventilation, what is the goal SpO2 and PaO2?

Answer 34

SpO2: 90-95%
PaO2: 55-60 mm Hg

Question 35

Rank the FiO2 of each of these: Venturi, simple face mask, LFNC, non-rebreather.

Answer 35

Venturi: 21-40%
LFNC: 21- 50%
Simple face mask: 40-60%
Non-rebreather: 80-100%