Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

MBBS 3: Internal Medicine > Oxygen Therapy > Flashcards

Oxygen Therapy Flashcards

1
Q

Why is oxygen needed for survival?

A

for energy
- oxidative phosphorylation
Glucose + O2 > CO2 +H2O + 38 ATP

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What is anoxia?

A

no oxygen availability in tissues

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

HYpoxia?

A

lack of oxygen availability in tissues

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Hypoxemia?

A

lack of oxygen in the blood

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What is FiO2?

A

fraction of O2 in inspired gas
Note: we normally breathe in 21%

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What are the FiO2 percentages in 1 to 6 liters?

A

1 L\min = 24%
2 L\min = 28%
3 L\min = 32%
4 L\min = 36%
5 L\min = 40%
6 L\min = 44%

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What are the normal SaO2 values?

A

95 - 100%

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Normal PaO2 values?

A

arterial blood - 75-100 mmHg

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What is oxygen therapy?

A

the administration of oxygen at concentrations greater than that in room air to treat or prevent hypoxia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Is oxygen a drug?

A

yes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Clinical goal of O2 therapy?

A
  1. Treat hypoxia
  2. Decrease work of breathing
  3. Decrease myocardial work
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What are the types of hypoxia?

A
  1. Hypoxic hypoxia
  2. Anemic Hypoxia
  3. Stagnant hypoxia
  4. Histotoxic hypoxia
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What is hypoxic hypoxia?

A

when your tissues don’t get enough oxygen

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Causes of hypoxic hypoxia?

A
  1. O2 poor air, hypoxic gas mixture
  2. High altitude
  3. Hypoventilation
  4. Shunts – septal defects
  5. Diffusion defects – pneumonia, lobar collapse
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What is anemic hypoxia?

A

Oxygen carrying capacity of blood is decreased

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Causes of anemic hypoxia?

A
  1. Anemia
  2. Altered Hemoglobin: CO Poisoning
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Describe how CO poisoning causes anemic hypoxia?

A
  1. CO reacts with oxygen, creating carboxy hemoglobin, which leads to tissue hypoxia.
  2. In the case of toxic concentration, increases in carboxyhemoglobin interfere with gas exchange in respiratory system, resulting in hypoxemia.
18
Q

What is stagnant hypoxia?

A

inadequate tissue perfusion

19
Q

Causes of generalized stagnant hypoxia?

A
  1. Hypovolemia
  2. Mitral Stenosis
  3. Constrictive pericarditis
  4. Myocardial ischemia
    NB - all the above conditions reduce the perfusion of organs by reducing the amount of blood that gets to them
20
Q

Causes of localized hypoperfusion stagnant hypoxia?

A
  1. Arterial obstruction
  2. thrombus
  3. oedema
    NB - in this instant there is a certain area that is not being perfused due to the reasons above
21
Q

Qhat is histotoxic hypoxia?

A

cells cant utilize the oxygen

22
Q

Causes of histotoxic hypoxia?

A

Electron transfer system of cytochrome oxidase is paralyzed
E.g. cyanide poisoning

23
Q

How does cyanide poisoning cause histotoxic hypoxia?

A
  • Cyanide is a potent cytochrome c oxidase (COX, a.k.a. Complex IV) inhibitor
  • As such, cyanide poisoning is a form of histotoxic hypoxia, because it interferes with oxidative phosphorylation
24
Q

Types of hypoxia that benefit from O2 therapy?

A
  1. hypoxia
  2. anemic
  3. stagnant
25
Q

Hypoxia that does not benefit from O2 therapy?

A

histotoxic

26
Q

What are the indications for O2 therapy?

A
  1. Hypoxia – when PaO2 comes down to 60mmHg
  2. Normoxic hypoxia – like low cardiac output state, anemia, CO Poisoning
  3. Trapped gases – like obstruction, pneumocephalus (air in the brain)
  4. Special situation – like anesthesia
27
Q

Clinical presentation of acute hypoxia?

A
  1. Restlessness
  2. Disorientation, confusion
  3. In-coordination, impaired judgment
  4. Hyperventilation - air hunger
  5. Circulatory changes (tachycardia > brady
28
Q

Clinical presentation of chronic hypoxia?

A
  1. Fatigue, drowsiness
  2. Inattentiveness
  3. Apathy
  4. delayed reaction time
29
Q

How do you assess the need of O2?

A
  1. Presence of clinical indicators
  2. Measurement of inadequate oxygen saturation
    - Arterial blood gas
    - Pulse oximetry
30
Q

What are low flow O2 delivery systems?

A

contribute partially to inspired gas client breathes
e.g. nasal cannula, simple mask , non-re breather mask , rebreather mask

31
Q

What are high flow O2 delivery systems?

A

deliver specific and constant percent of oxygen independent of client’s breathing
e.g. Venturi mask, trach collar, T-piece

32
Q

Describe a nasal cannula?

A
  • The prongs protrude 1 cm into nares
  • Used for low concentrations of Oxygen 24-44% at 1-6L/min.
  • Patient are able to talk and eat with oxygen in place
  • May cause irritation to the nasal and pharyngeal mucosa
  • If oxygen flow rates are above 4 L/min variable FiO2
33
Q

Describe a simple face mask?

A
  • Client exhales through ports on sides of mask
  • Air entrained through ports if O2 flow through does not meet peak inspiratory flow
  • It delivers 35% to 60% oxygen at 6-10 L/min.
  • Flow must be at least 5 L/min to avoid CO2 build up and resistance to breathing
  • Potential for skin breakdown due to pressure and moisture
  • Uncomfortable while eating or talking and Obstruct coughing.
34
Q

Describe a rebreather mask?

A
  • It is used to deliver oxygen concentrations up to 80% at 8-12L/m.
  • O2 directed into reservoir
  • it works by:
    1. Inspiration: draw gas from bag & room air
    2. Expiration: first 1/3 of exhaled gas goes into bag (dead space)
    3. Dead space gas mixes with ‘new’ O2 going into bag
    NB: Bag should remain at least 1/3 full during inspiration
35
Q

Describe a nonrebreather mask?

A
  • Have 2 one-way valves at exhalation ports and bag
  • This mask provides the highest concentration of oxygen (95-100%) at 10-15L/min.
  • Client can only inhale from reservoir bag
  • Valve prevents exhaled gas flow into reservoir bag
  • Valve over exhalation ports prevents air entrainment.
  • Bag must remain inflated at all times
  • For Critical illness / Trauma patients, Post-cardiac or respiratory arrest
  • Effective for short term treatment
36
Q

Describe venturi (fixed performance) masks?

A
  • It is high flow concentration of oxygen.
  • Oxygen from 24 - 60% At liters flow of 4 to 15 L/min.
  • Aims to deliver constant and most precise oxygen concentration within and between breaths.
  • With TACHYPNOEA (RR >30/min) the oxygen flow should be increased by 50%
  • Increasing flow does not increase oxygen concentration, it is a fixed dose device
  • Good device for patients with raised C02 (patients with a target of 88-92%)
37
Q

Hazards of O2 therapy?

A
  1. Drying of mucous membrane
  2. Depression of ventilation in COPD
  3. Reversal of compensatory hypoxic vasoconstriction
  4. Atelectasis due to absorption collapse
  5. O2 toxicity
38
Q

How to optimize O2 delivery by repositioning the patient?

A
  1. Avoid laying patient flat on back.
  2. Raise head of bed.
  3. Encourage deep breathing/coughing
39
Q

How to improve the mechanics of breathing in a patient?

A
  1. Patient position - Semi-Fowlers position
  2. Pursed lip breathing
  3. Abdominal breathing.
  4. Anxiety relief
40
Q

How to evaluate if the patient has received enough O2?

A
  1. Breathing pattern regular and at normal rate.
  2. pink color in nail beds, lips, conjunctiva of eyes.
  3. No confusion, disorientation, difficulty with cognition.
  4. Arterial oxygen concentration or hemoglobin
  5. Oxygen saturation within normal limits.

MBBS 3: Internal Medicine (72 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions