oxygen therapy

Question 1

Who does the oxygen therapy guideline apply to?

Answer 1

anyone above the age of 12

Question 2

define adequate oxygen levels according to spo2?

Answer 2

Spo2 > 92% RA

Question 3

Spo2 range for Mild- mod hypoxaemia

Answer 3

85-91%

Question 4

Management of mild-mod hypoxaemia

Answer 4

Nasal cannula 2-6l/min

hudson mask 5-10l/min

Question 5

Spo2 range for severe hypoxaemia

Answer 5

<85% or critical illness

Question 6

outline the critical illness

Answer 6

1. cardiac arrest/resus
2. major trauma/head injury
3. anaphylaxis
4. shock
5. status epilepticus (seizure)
6. severe sepsis
7. ketamine sedation

Question 7

Management of severe hypoxaemia

Answer 7

Non-rebreather 10-15l/min
if inadequate Tidal volume ventilate BVM
once haemodynamically stable titrate to 92-96%
if deteriorate continue BVM 100% O2, consider SGA

Question 8

list of chronic hypoxaemia

Answer 8

1. COPD
2. Obesity
3. Cystic fibrosis
4. bronchiectasis
5. Neuromuscular disorder
6. severe kyphoscoliosis

Question 9

Management of chronic hypoxaemia

Answer 9

titrate to 88-92%
Nasal prongs 2-6l/min
Hudson mask 5-10l/min
if deteriorates treat as severe

Question 10

regardless of SPO2

Answer 10

1. Toxic gases
2. Decompression illness
3. Cord prolapse
4. Post partum haemorrhage
5. Shoulder dystocia
6. Cluster headache

Mx with Non-rebreather 10-15l/min

Question 11

What conditions are not routinely treated with oxygen?

WHY???

Answer 11

1. Acute coronary syndrome
2. stroke
3. arrhythmia
   Why? this pts may c/o feeling SOB, the cause of SOB is a reduction in blood flow to tissues, due to obstruction (clot), leading to ischaemia of tissues

Question 12

what do you do if you are unable to obtain SPO2?

Answer 12

if pt appears hypoxic or SOB admin oxygen 2-6l/min via nasal prongs, or 5-10l/min via hudson mask

Question 13

SPO2 can be unreliable in pt with?

Answer 13

1. nail polish
2. hypotension
3. cold hands
4. peripheral vascular disease
5. anaemia
6. peripherally shutdown
7. severe asthma
8. carbon dioxide poisoning

Question 14

Spo2 goal for paraquat & bleomycin poisoning?

Answer 14

85-88%

Question 15

why do we aim for 85-88% Spo2 in paraquat/bleomycin poisoning?

Answer 15

these substances lead to pulmonary damage by triggering the release of oxygen free radicals which can lead to lung damage, causing pulmonary oedema/fibrosis

Question 16

what is bleomycin?

Answer 16

bleomycin is a type of antibiotic used in the treatment of cancers such as non-Hodgkin’s/Hodgkin lymphoma, testicular and cervical cancer. Bleomycin works by inhibiting DNA synthesis, stopping or slowing the growth of cancer cells

Question 17

what is paraquat?

Answer 17

paraquat is a form of herbicide, different to organophosphates.

Question 18

benefit of upright position in pts

Answer 18

• aids in inspiration/expiration
• gas exchange improves
• gravity exerts pressure on the lungs, compressing the base of the lungs against the diaphragm, increasing surface area & exposing more alveoli for gas exchange. alveoli in bases are smaller, more numerous, meaning less o2 required for gas exchange.

Question 19

what is kyphoscoliosis?

Answer 19

Kyphoscoliosis is a condition that causes the abnormal curvature of the thoracic lumbar spine. this condition can lead to the chest wall malformation. this impairs mechanics of respiration, leading to poor chest wall compliance, causing hypoventilation, hypercapnia and respiratory failure. impairs muscles at nerve junctions impairing respiration

Question 20

what is bronchiectasis?

Answer 20

Bronchiectasis is a condition in which the lungs/bronchioles become damaged causing airway to permanently widen & impairs mucus clearance, leading to infection and increased dead space.

Question 21

What is capnography?

Answer 21

Capnography is the numerical measurement & graphical display of CO2 through respiratory cycle.

ETCO2 – is the measurement of Co2 in the airway at the end of each breath

Question 22

normal ETCO2 range

Answer 22

35-45mmHg

arterial 38-45mmHg

Question 23

what happens to ETCO2 when you get rosc

Answer 23

spike due to restoration of circulation (restores co2)

Question 24

what happens to ETCO when patient arrests

Answer 24

fall or drop, due to loss of circulation

Question 25

What is the purpose of PEEP?

Answer 25

The benefit of PEEP is to increase the functional residual capacity and reduce pulmonary compliance. Meaning increases pressure in the lungs at the end of expiration, reducing the stretch of the lungs, decreasing the lung volume, improving gas exchange

Question 26

What does PEEP stand for?

Answer 26

Positive end expiratory pressure

Question 27

What is the benefit of elastic recoild in the lungs?

Answer 27

Helps return lungs to resting state and enables passive exhalation. Assists in gas exchange

Question 28

What does work of breathing refer to?

Answer 28

WoB refers to the effort required to move air throughout the conducting airways and the ease of lung compliance

Question 29

What is shunting?

Answer 29

Refers to deoxygenated blood that does not participate in gas exchange

Question 30

Deadspace refers to

Answer 30

An area of no gas exchange

Question 31

Affinity hypoxia is

Answer 31

Hypoxia as a result of failure of haemoglobin to release oxygen to tissues

Question 32

Anaemic hypoxia is

Answer 32

Hypoxia that is due to reduce oxygen carrying capacity of blood as a result of decrease in haemoglobin or alteration of haemoglobin

Question 33

Historic hypoxia is

Answer 33

Impair utilisation of oxygen by tissues

Question 34

Hypoxemic hypoxia is

Answer 34

A lack of oxygen reaching the blood, for example high altitude

Question 35

Stagnant hypoxia is

Answer 35

Failure to transport sufficient oxygen because of inadequate blood flow