Brainscape's Knowledge GenomeTM

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


See full index

103 theme 4 > Oxygen therapy and sleep apnoea > Flashcards

Oxygen therapy and sleep apnoea Flashcards

1
Q

what are oxygen sources

A 
Oxygen cylinders 
Wall supply
Oxygen concentrators
Liquid oxygen 
Delivered in Litres per minute
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

what are oxygen cylinders

A 
Widely available (home and institutions)
Various sizes
Limited length of supply
Suitable for limited/short duration treatment
Relatively expensive
Supply 100% oxygen
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

what is a wall supply

A

In hospital only
Central supply in piped clinical areas
May not be available in all areas (eg clinic rooms)
Supply 100% oxygen

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

what are oxygen concentrators

A 
Mains operated machine 
Molecular sieve – removes nitrogen
Oxygen predominant gas so >90% oxygen 
Use in home or when out
Regional suppliers with franchise for installation and support
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

what is liquid oxygen and its uses

A

More highly compressed
Larger gaseous volume
Allow higher flow rate
Well-developed in US and parts of Europe

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

what are patients interfaces

A

For spontaneously breathing patients
Nasal cannulae
Uncontrolled masks (Hudson, non rebreathe)
Controlled (fixed percentage – ventur) masks

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

how does oxygen reach patient via interfaces

A

Litres per minute or percentage inspired oxygen

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

what is nasal cannula

A 
Usually well tolerated
Accepts flow rates 1-4 l per min
Delivers 24-40% O2 
% delivered depends on multiple factors 
Used for mild hypoxemia, not critically ill
Can dry out nose
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

what are uncontrolled masks

A 
Simple face mask
Hudson mask
Delivers 30-60% O2
Flow rate 5-10 l/min
Mix of O2, room air and exhaled air in mask 
Used less often
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

what are uncontrolled masks (non rebreathe)

A

Delivers 85-90% oxygen with 15L flow rate
Bag one way valve stops mixing with room air and patient rebreathing expired air
Used in acutely unwell patients (step down ASAP)

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

what is a Venturi mask

A

Controlled oxygen

Venturi valve allows delivery of a fixed concentration of oxygen

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

how is oxygen a drug

A

Can save lives with oxygen but can also do harm
How given depends on clinical circumstances and patients medical background (eg COPD)
Oxygen should be prescribed on drug chart with target oxygen saturations

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

what are the clinical indications for oxygen use

A

used for hypoxaemia, not breathlessness
Acutely hypoxaemic patients
Chronically hypoxaemia COPD patients with acute exacerbation
Chronically hypoxaemic COPD patients who are stable
Palliative use in advanced malignancy (sats <90% and breathless, often multifactorial)

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

what are the target oxygen saturations

A 
Normal young adult 96-98%
Over 70 94-98%
Target for most 94-98%
Balance of what is normal and safe
Target for those at risk of hypercapnic respiratory failure is 88-92% - lower for some
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

what is acute breathlessness with hypoxaemia a risk of

A

Risk is acute hypoxaemia leads to acute cardiac dysrhythmia and organ failure
Treatment with maximal oxygen, high flow uncontrolled mask (first line), alter flow and delivery device when stable

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

what needs to be considered besides giving oxygen

A

Not just about oxygen
Secure and maintain airway patency
Enhance circulation (volume, anaemia, CO)
Avoid/reverse resp depressants
Establish reason for hypoxaemia and treat
If not improving, may need ventilation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Who is at risk of hypercapnia if given high dose oxygen

A

Chronic hypoxic lung disease (COPD, CF)
Chest wall disease
Neuromuscular disease
Obesity related hypoventilation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

how are chronically hypoxaemia patients with COPD who have acute exacerbation treated

A

Maintain modest oxygenation whilst preventing CO2 retention and acidosis
Deliver oxygen by fixed percentage venturi mask starting at 24%
Target 88-92%

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

how can response to oxygen treatment be assessed

A

Arterial blood gases, check frequently
pO2 <10, pCO2 falling from peak to maintained <6, pH increasing/maintained >7.35
adjust dose of oxygen accordingly
not improving=non invasive ventilation

20
Q

if a patients is not improving why shouldn’t you use nasal cannulae

A

potentially dangerous as actual inspired oxygen percentage varies according to patients respiratory characteristics
uncontrolled therapy

21
Q

how is oxygen prescribed

A

target O2 sat range, the delivery device and the dose (flow rate or percentage inspired oxygen)
may have an oxygen treatment card with recommended O2 sats/prescription

22
Q

what is LTOT

A

Long term oxygen therapy
For some COPD patients
Specialist assessment – in patients stable state and no sooner than 4 weeks after an exacerbation

23
Q

what are the LTOT indications

A

COPD pO2 <7.3kPa or 7.3-8kPa with a complicating disorder

24
Q

how is LTOT provided

A

Provided with an oxygen concentrator
Regional concentrator supply service
O2 treatment for >15 hours per day

25
Q

what are the benefits of LTOT

A 
Improved long term survival 
Prevention of deterioration in pulmonary hypertension
Reduction of polycythaemia (raised Hb)
Improved sleep quality
Increased renal flow
Reduction in cardiac arrythmias
Improved quality of life
26
Q

what is portable oxygen in terms of LTOT

A

Improves breathlessness in some patients
May extend duration of LTOT
BUT most patients breathlessness is not due to low pO2
Weight of cylinders
Duration of supply

27
Q

what is sleep apnoea

A

Apnoea (cessation of airflow for 10 seconds or longer)
Central – resp control centre – no resp effort
Obstructive: collapse of pharyngeal airway during sleep (cont of respiratory effort)
OSA 5 or more obstructive apnoeas per hour

28
Q

what is hypopnea

A

reduction in airflow by 50% accompanied by desaturation of 4% and or arousal from sleep

29
Q

what is the prevalence of apnoea

A

2% adult women and 4% adult men, increasing incidence

30
Q

what are the risk factors of apnoea

A 
Male sex
Obesity 
Neck circumference
Smoking
Alcohol/sedative use
Craniofacial abnormalities 
Pharyngeal abnormalities
Some medical conditions like hypothyroidism or pregnancy)
Sleeping supine
31
Q

what is the pathophysiology of apnoea

A

nasal: polyps or deviated septum
enlarge tonsils
pharynx: dec in neuromuscular tone or caliber, inc in resistance
inc soft tissue: eg obesity or hyperthyroidism
abnormal chin: micronathia, retognathia
normal tongue relaxation and any causes of marcoglossia

32
Q

what happens in sleep apnoea

A

sleep
muscles/tissues relax (pharyngeal airway)
collapse and obstruction of airway - snoring
apnoea
arousal
muscle tone returns and airway clears
resumption of breathing

33
Q

what are the clinical features of sleep apnoea

A 
Snoring 
Nocturnal choking/waking with a start
Unrefreshing/restless sleep
Morning dry mouth or headaches 
Excessive daytime sleepiness (difficulty concentrating, irritability or mood changes, sleeping at inappropriate times)
Nocturia
34
Q

what are the complications of apnoea

A 
Cor pulmonale (right heart failure 2ndry resp distress)
Secondary polycythaemia
35
Q

what are investigations of apnoea

A

Repetitive apnoeas and symptoms of sleep fragmentation

Epworth sleepiness scale or sleep studies (eg polysomnography via sensors and monitoring technician)

36
Q

what is the epworth sleepiness scale

A

list of 8 situations, asked to rate from 0- no chance of drifting off to 3 - almost definitely driving off
over 10- apnoea/concerning

37
Q

how is apnoea diagnosed

A 
Uses apnoea/hypopnea index
AHI= apnoeas + hypopneas / total sleep time in hours 
Mild 5-14 per hpur (= saigns/symptoms)
Mod 15-30
Severe more than 30 
Or oxygen desaturation index
38
Q

what are consequences of OSA

A 
Increased risk of accidents 
Associated with 
Hypertension
Type 2 diabetes
IHD
HF
Stroke
Cardiac arrythmias
Death
39
Q

How is OSA managed

A 
Goals 
Resolve signs and symptoms of OSA
Improve sleep quality
Normalise AHI and oxygen saturations
Multi-disciplinary approach
40
Q

how can patients managed their OSA

A 
Patient education eg driving 
Behavioural change 
Weight loss
Avoid sleeping supine 
Avoid alcohol 
Treat contributing problems 
Review medications eg sedating drugs or those causing weight gain
41
Q

How can OSA be treats

A

Mandibular advancement devices
CPAP
surgery

42
Q

what are mandibular advancement devices

A

Hold soft tissues of oropharynx forward, mild to mod OSA, patient pref, failed CPAP

43
Q

how is surgery used to treat apnoea

A

most effective if severe, correctable, obstructing lesion

Tonsillar or adenoid hypertrophy, craniofacial abnormalities

44
Q

what is CPAP

A

Continuous positive airway pressure (device generates airflow > positive pressure delivered via mask, intraluminal pharyngeal pressure > surrounding pressure, pharynx stays open)

45
Q

When is CPAP used

A

Patients with mild OSA and additional co morbidities
“ and high risk profession
Patients with moderate/severe OSA regardless of symptoms
Not mild with no additional risk factors who aren’t excessively sleepy

46
Q

what are the benefits of CPAP

A

Symptoms resolve
Decrease in apnoea/hypopnea, daytime sleepiness and risk road accidents
Increase quality of life
Normalise BP

47
Q

What are the issues with CPAP

A

Adherence
Airway drying or irritation (can humidify)
Mask issues (air leak or comfort)
Normally life long treatment

103 theme 4 (20 decks)

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