Respiratory monitors and equipment

Question 1

Which point is CO2 measured on the capnography tracing?

Answer 1

D

Question 2

There are 4 phases to the capnography waveform. What are they?

Answer 2

I. Exhalation of anatomic dead space

II. Exhalation of anatomic dead space + alveolar gas

III. Exhalation of alveolar gas

IV. Inspiration of fresh gas that does not contain CO2

Question 3

What is a normal alpha angle on capnography?

Answer 3

100-110 degrees

Question 4

How many degrees should beta angle be?

Answer 4

90

Question 5

What does an increased alpha angle mean?

Answer 5

Airflow obstruction such as COPD, bronchospasm, kinked ETT

Question 6

What will beta angle look like if rebreathing is happening?

Answer 6

Increased angle

Question 7

If beta angle is widened on capnography think:

Answer 7

Rebreating

Question 8

If alpha angle is increased on capnography think:

Answer 8

Airflow obstruction

Question 10

There are 2 methods of CO2 analysis. What are they?

Answer 10

Mainstream (in line)
Sidestream (Diverting)

Question 11

Briefly describe mainstream CO2 analysis

Answer 11

The device is attached to the ETT. It provides a faster response time. Because its attached to the ETT, it does increase dead space. No water trap or pump is needed.

Question 12

Briefly describe sidestream CO2 analysis

Answer 12

Device is located outside of the airway. Pumping mechanism cont. aspirates the gas sample from the breathing circuit -> slower response time

water trap required

Question 13

What does an airflow obstruction make the capnography waveform look like?

Answer 13

Prolonged upstroke with increased alpha angle

Question 14

Examples of why airflow obstruction would occur

Answer 14

COPD
Bronchospasm
Kinked ETT

Question 15

Why are cardiac oscillations more common in children on capnography?

Answer 15

Close proximity of the heart to the lungs

Question 16

What does curare cleft suggest when a patient is breathing spontaneously?

Answer 16

Inadequate muscle relaxant reversal (lack of synchronization b/w intercostal muscles and diaphragm)

Question 17

What does curare cleft suggest when a patient being mechanically ventilated?

Answer 17

Spontaneous breaths during mechanical ventilation

Question 18

3 reasons why you may have low ETCO2 on capnography waveform?

Answer 18

Hyperventilation, decreased CO2 production, or increased alveolar dead space

Question 19

How much higher is PaCO2 than EtCO2?

Answer 19

2-5 mmHg

Question 20

Which law is the Pulse Ox based on?

Answer 20

Beer-Lambert

Question 21

The pulse ox emits how many wavelengths of light at a constant intensity?

Answer 21

TWO

Question 22

How many sensors are on the other side of the light

Answer 22

two

Question 23

What are the 2 lights of the pulse ox called?

Answer 23

Red light
Near infrared

Question 24

What are the nm of the 2 lights of the pulse ox?

Answer 24

Red light- 660
Near infrared light- 940

Question 25

Red light is preferentially absorbed by deoxyhgb or hgb?

Answer 25

Deoxyhgb

Question 26

Near infrared light is preferentially absorbed by deoxyhgb or oxyhgb?

Answer 26

oxyhemoglobin

Question 27

Most responsive sites to arterial desaturation that will change pulse ox ASAP are:

Answer 27

Ear, nose, tongue, esophagus, forehead

Question 28

Which gives slower responsiveness on SpO2 reading?

Answer 28

Toe is slower than finger

Question 29

How can SpO2 be skewed when it is monitored on the head or the esophagus and pt is put in Trend position?

Answer 29

It can look falsely decreased due to venous engorgement.

Question 30

How is the pulse ox calculated?

Answer 30

As a ratio between how much light is absorbed arterially and how much is absorbed on the venous end

Question 31

A PaO2 of 60 corresponds to a SpO2 of _?

Answer 31

90

Question 32

A PaO2 of 50 corresponds to a SpO2 of _?

Answer 32

80

Question 33

A PaO2 of 40 corresponds to a SpO2 of _?

Answer 33

70

Question 34

Ways to imporve the SpO2 signal?

Answer 34

Place a digital block Warm the extremity Protect the extremity from ambient light Apply a vasodilating cream Administer an arterial vasodilator

Question 35

SpO2 measures saturation of what?

Answer 35

Hemoglobin

Question 36

What side should the pulse ox be placed during mediastinoscopy?

Answer 36

Right side to assess for brachiocephalic or innominate artery compression

Question 37

Will the pulse ox over or under estimate the SpO2 with severe anemia?

Answer 37

Over

Question 38

Pulse ox can only detect arterial and venous O2 hgb saturation. What is needed to detect methgb or carboxyhgb?

Answer 38

co-oximeter

Question 39

How much light does methgb absorb?

Answer 39

660 and 940 equally

Question 40

Whta is a pulse ox when methgb is present?

Answer 40

85%

Question 41

How much light does carboxyhgb absorb?

Answer 41

660 nm to the same degree as OxyHgb

Question 42

Carboxyhgb looks the same as what hgb on pulse ox?

Answer 42

oxyhgb which means the pulse ox sums these up together

Question 43

WIth carboxyhgb present, is SpO2 over or under estimated?

Answer 43

OVER! Since carboxy and oxyhgb will be added

Question 44

What are 2 examples of non-pulsatile flow that can cause innacuracy of SpO2?

Answer 44

cardiopulmonary bypass LVAD

Question 45

What kind of valve defect can falsely decrease SpO2?

Answer 45

Tricuspid Regurg

Question 46

Do acrylic or dark nails affect SpO2?

Answer 46

Dark nails not acrylic! Green blue black

Question 47

Where should pulse ox be placed to best prevent corneal abrasion on emergence?

Answer 47

Anywhere but the index finger because THEY WILL wake up and start rubbing them eyes

Question 48

What kind of laser does Raman Scatter Spectrometry use?

Answer 48

Argon laser

Question 49

Piezoelectric crystals incorporate what kind of layer?

Answer 49

Lipid layer

Question 50

All gases except for which one absorb infrared light?

Answer 50

O2

Question 51

Barotrauma risk increases when the plateau pressure exceeds _

Answer 51

35 cmH2O

Question 52

Complications of an elevated plateau pressure

Answer 52

ventilator associated lung injury pneumothorax pneumomediastinum SUBQ emphysema

Question 53

In the adult, normal static compliance is In the child?

Answer 53

35-100 mL/cmH2O > 15 mL/cm H2O