Oxygenation

Question 1

Define pulse oximetry

Answer 1

• Transcutaneous measurement of light wavelengths to calculate arterial oxygen saturation
• Oxygenated and deoxy blood have differing absorption of light spectra

Question 2

Define capnography

Answer 2

• Monitoring of CO2 levels via nasal cannula (normal is 35-37 mm Hg)
• Frequently used during moderate sedation

Question 3

Proper size of nasopharyngeal airway?

Answer 3

Tip of nose to tragus of ear

Question 4

Proper size of oropharyngeal airway?

Answer 4

Corner of mouth to angle of mandible

Question 5

When is a nasal cannula indicated?

Answer 5

Mild hypoxia (91-94%) 
(delivers 1-6 L/min)

Question 6

When is a non-rebreather mask indicated?

Answer 6

Moderate hypoxia (86-91%)
(delivers up to 15 L/min)

Question 7

Advantages of non-rebreather mask

Answer 7

Able to deliver high volume of O2 without risk of rebreathing patient’s own CO2

Question 8

When is a Venturi mask indicated?

Answer 8

COPD patients

PO2 86-91%

Question 9

Advantages of Venturi mask

Answer 9

Able to fix a concentration of oxygen

Question 10

What is non-invasive ventilation?

Answer 10

• BiPAP and CPAP

- Pressurized oxygen delivery devices which provide support in early respiratory failure

Question 11

Describe BiPAP

Answer 11

• Cycles b/w a targeted peak inspiratory pressure and a lower expiratory pressure
• Ventilation varies with patient effort

Question 12

Indications for BiPAP

Answer 12

COPD, asthma, CF, PNA, sleep apnea

Question 13

Describe CPAP

Answer 13

Delivers a static airway pressure maintained throughout inspiratory and expiratory cycle

Question 14

Indications for CPAP

Answer 14

Same as BiPAP but PREFERRED for CHF and sleep apnea

Question 15

Describe intubation

Answer 15

Placement of endotracheal tube orally for direct ventilation

Question 16

Define rapid sequence intubation (RSI)

Answer 16

Intubation including sedation and paralysis

Question 17

Indications for intubation

Answer 17

• Inability of pt to protect own airway
• Failure to oxygenate
• High potential for deterioration
• Pt/staff safety

Question 18

MC meds used in intubation

Answer 18

• Etomidate (sedative)

- Succinylcholine (paralytic)

Question 19

Describe hyperbaric oxygen therapy

Answer 19

Administration of 100% oxygen under pressure, usually 2.5x higher than normal atmospheric pressure

Question 20

Purpose of hyperbaric oxygen therapy

Answer 20

• Blood can be hyperoxygenated by dissolving O2 within the plasma
• O2 carried to areas where circulation is diminished/blocked

Question 21

What readings are WNL for pulse oximetry?

Answer 21

95-100% (with a good waveform)

Question 22

Uses of nasopharyngeal airway

Answer 22

• Diminished gag
• Trismus
• Oral injuries
• Intoxication

Question 23

When is an oropharyngeal airway used?

Answer 23

Spontaneous breathing but no gag

Question 24

What does an oropharyngeal airway do?

Answer 24

• Holds tongue off posterior pharyngeal wall

- Provides opening for air/suction

Question 25

What is applied after insertion of oropharyngeal airway?

Answer 25

O2 mask

Question 26

Advantages of nasal cannula

Answer 26

- Talk, eat, drink w/o removing cannula | - Mouth breathing is possible w/o affecting function

Question 27

Disadvantages of nasal cannula

Answer 27

Irritation to nasal mucosa both by dry oxygen and physical abrasion (causing epistaxis or rhinitis)

Question 28

What does a non-rebreather mask contain?

Answer 28

Oxygen reservoir with one way CO2 valve

Question 29

Disadvantages of non-rebreather mask

Answer 29

- Claustrophobia | - Difficulty speaking/eating

Question 30

Adverse effects of non-invasive ventilation

Answer 30

- Anxiety (pt may strain and increase work of breathing) - Decreased CO (d/t increased intrathoracic pressure) - Barotrauma - Gastric distention

Question 31

Importance of pre-procedure passive oxygenation?

Answer 31

Extends duration of safe apnea via de-nitrogenating the residual capacity of the lungs (which maximizes O2 storage within the lungs)

Question 32

Define safe apnea

Answer 32

Time until a patient reaches a saturation level of 88-90%

Question 33

How should a pt be positioned for pre-procedure passive oxygenation?

Answer 33

External auditory meatus on same horizontal plane as sternal notch (approx 20 degrees from horizontal) (OR reverse Trendelenburg)