Module 2: Airway

Question 1

Tidal volume calculations

Answer 1

Ideal body weight. 6-8ml/kg

Question 2

Ideal body weight calculations

Answer 2

Male: 50 + (height in inches - 60 x 2.3)
Female: 45.5 + (height in inches - 60 x 2.3)

Question 3

Ventilation rates for adults

Answer 3

CPR: 10BPM with an advanced airway placed
Rescue breathing: 12BPM
EtCO2: 35-45mmHg

Question 4

LEMON scoring

Answer 4

Look (externally): 0-4pts
Evaluate (3-3-2): 0-3pts
Mallampati: 0-1pt
Obstruction: 0-1pt
Neck mobility: 0-1 pt

Question 5

Mallampati classification

Answer 5

I: whole posterior pharynx exposed
II: posterior pharynx partially exposed
III: base of uvula exposed
IV: no posterior structures visible

Question 6

Suction pressures

Answer 6

Adult: 120mmHg
Pediatric: 80-120 mmHg
Infant: 80 mmHg

Question 7

Phase 1 capnogram.

Answer 7

Dead space ventilation. Represents start of exhalation at A - B

Question 8

Phase 2 capnogram

Answer 8

Ascending phase (B - C). Rapid rise in CO2 as CO2 from alveoli reaches the upper airway.

Question 9

Phase 3 capnogram

Answer 9

Alveolar plateau (C - D). CO2 reaches a uniform level. End point of the phase represents end tidal CO2, and start of inspiration.

Question 10

Phase 4 capnogram

Answer 10

Inspiratory cycle (D - E)

Question 11

Possible causes of increasing ETCO2

Answer 11

Hypoventilation, decreased tidal volume, possible obstruction, increased BMR, rapid rise in body temperature

Question 12

Possible causes of decreasing ETCO2

Answer 12

Hyperventilation, hypothermia, paralysis, decreased CO, increased tidal volume, metabolic acidosis, cardiogenic shock, V/Q mismatch

Question 13

Possible causes of rising baseline in ETCO2

Answer 13

Rebreathing: insufficient expiratory time, faulty expiratory valve on vent, inadequate inspiratory flow.

Question 14

Possible causes of change of ascending slope in ETCO2

Answer 14

Obstruction in the expiratory limb of breathing circuit, FBAO, bronchospasm, kinked or occluded artificial airway.