Respiratory Failure

Question 1

Oxygen cascade

Answer 1

Decrease in oxygen as it passes from the atmosphere into the body and into arterial circulation

Question 2

Concentration of O2 in air

Answer 2

20.94%

Question 3

Barometric pressure

Answer 3

101.3kPa

Question 4

PO2 dry air at sea level

Answer 4

21.2kPa

Question 5

Tracheal gas

Answer 5

PO2 after humidification

19.9kPa

Question 6

Alveolar PO2 affected by

Answer 6

Hypo or hyper ventilation
Oxygen consumption
CO2 production

Question 7

PAO2 equation

Answer 7

PAO2= dry barometric pressure x (FiO2-VO2/VA)

Question 8

PAO2 equation 2

Answer 8

PiO2-(PaCO2/R)

Question 9

Normal PaO2

Answer 9

13.6kPa

Question 10

Shunting

Answer 10

An area of the lung that is perfused but not ventilated

Increases in disease

Question 11

Oxygen Delivery

Answer 11

[Hb] x O2 saturation of Hb x 1.34 x 10 x CO

Question 12

Signs of Resp Failure

Answer 12

Resp Compensation
Increased Sympathetic tone
End organ hypoxia
Haemoglobin desaturation
CO2 retention

Question 13

Resp Compensation

Answer 13

Tachypnoea
Use of accessory muscles
nasal flaring
Intercostal or suprasternal recession

Question 14

Increased Sympathetic Tone

Answer 14

Tachycardia
Hypertension
Sweating

Question 15

End Organ Hypoxia

Answer 15

Altered mental status
Bradycardia
Hypotension

Question 16

Haemoglobin desaturation

Answer 16

Cyanosis

Question 17

CO2 retention

Answer 17

Flap

Bounding Pulse

Question 18

Resp Failure

Answer 18

Syndrome where respiratory system fails in one of both of its gas exchange functions- oxygenation + CO2 elimination

Question 19

Type 1 Resp Failure

Answer 19

Hypoxaemia only

PaO2 < 8kPa

Question 20

Type 1 Resp Failure MOA

Answer 20

Damage to lung tissue
Prevents adequate oxygenation of blood (hypoxaemia)
Remaining lung tissue sufficient to excrete the CO2 produced

Question 21

Type 1 Resp Failure examples

Answer 21

Pneumonia
Obesity
P. oedema
Asthma/COPD
pulmonary embolism
pneumothorax

Question 22

Type 2 Resp Failure

Answer 22

Hypoxaemia + Hypercapnia
PaO2<8kPa
PaCO2>6.5kPa

Question 23

Type 2 Resp Failure MOA

Answer 23

Ventilatory Failure
Alveolar ventilation insufficient to excrete CO2 produced
Reduced ventilatory effort or inability to overcome increased resistance to ventilation

Question 24

Type 2 Resp Failure examples

Answer 24

Type 1 with fatigue

hypoventilation

Question 25

First line treatment

Answer 25

OXYGEN
Oxygen masks with nasal cannula
Face masks with reservoir bags
Venturi masks

Question 26

Low flow masks

Answer 26

Nasal cannulas etc.

Deliver variable concentration depending on how the patient is breathing

Question 27

Treatment sequence for Resp Failure

Answer 27

Oxygen
Pulse Oximetry
ABG

Question 28

Pulse Oximetry

Answer 28

Started immediately
Pulse Oximetry saturation (SpO2) of 94% is a critical threshold- below this, small fall in PaO2 produces sharp fall in SpO2
ONLY TELLS US ABOUT OXYGENATION NOT VENTILATION

Question 29

ABG

Answer 29

Used to keep fraction of inspired O2 to the minimum required to achieve adequate oxygenation
Used to evaluate pH changes + changes in PaCO2

Question 30

If SpO2 >94%, PaO2 should be

Answer 30

> 10kPa

Question 31

High levels O2

Answer 31

Dangerous + toxic

Produces free radicals

Question 32

CO2 retention

Answer 32

10% of COPD patients- CO2 will go up if given oxygen

Question 33

Ventilation

Answer 33

Not for hypoxia

Used for hypercapnia

Question 34

Oxygen vs Ventilation

Answer 34

O2 for hypoxia

Ventilate in hypercapnia (hypoventilation)

Question 35

COPD/Asthma

Answer 35

Bilateral hyper-expansion of the chest