Oxygen Flashcards
Oxygen should be regarded as a ___________
drug
Oxygen is prescribed for _____________ patients to increase ______________ and decrease the ______________
hypoxaemic
alveolar oxygen tension
work of breathing
The concentration of oxygen required depends on the _______________; the administration of an inappropriate concentration of oxygen can have serious or even fatal consequences
condition being treated
_______________ is probably the most common drug used in medical emergencies
Oxygen
Oxygen should be prescribed initially to achieve a normal or near–normal oxygen saturation; in most acutely ill patients with a normal or low arterial carbon dioxide (PaCO2), oxygen saturation should be __________% oxygen saturation
94–98
In some clinical situations such as _____________ and ______________ it is more appropriate to aim for the highest possible oxygen saturation until the patient is stable
cardiac arrest
carbon monoxide poisoning
In some clinical situations such as cardiac arrest and carbon monoxide poisoning it is more appropriate to aim for _____________ oxygen saturation until the patient is stable
the highest possible
A lower target of _________% oxygen saturation is indicated for patients at risk of hypercapnic respiratory failure
88–92
A lower target of 88–92% oxygen saturation is indicated for patients at risk of _______________
hypercapnic respiratory failure
High concentration oxygen therapy is safe in uncomplicated cases of conditions such as… (7)
- pneumonia
- pulmonary thromboembolism
- pulmonary fibrosis
- shock
- severe trauma
- sepsis
- anaphylaxis
*In such conditions low arterial oxygen (PaO2) is usually associated with low or normal arterial carbon dioxide (PaCO2), and therefore there is little risk of hypoventilation and carbon dioxide retention
High concentration oxygen therapy is safe in conditions where low arterial oxygen (PaO2) is associated with ____________ or___________ arterial carbon dioxide (PaCO2), and therefore there is little risk of ___________ and ___________
Low
Normal
Hypoventilation
Carbon dioxide retention
(ie. Low risk of type II respiratory failure)
In acute severe asthma, the arterial carbon dioxide (PaCO2) is usually _____________ but as asthma deteriorates it may _____________ (particularly in children)
Subnormal
rise steeply
- These patients usually require high concentrations of oxygen and if the arterial carbon dioxide (PaCO2) remains high despite other treatment, intermittent positive-pressure ventilation needs to be considered urgently.
Low concentration oxygen therapy (controlled oxygen therapy) is reserved for patients at risk of _____________ respiratory failure
hypercapnic (Type II resp failure)
Type II respiratory failure (hypercapnic resp failure) is more likely in those with … (7)
- COPD
- Advanced CF
- Severe non-cystic fibrosis bronchiectasis
- Severe kyphoscoliosis or severe ankylosing spondylitis
- Severe lung scarring caused by TB
- MSK disorders with respiratory weakness, especially if on home ventilation
- Overdose of opioids, benzos, or other drugs causing respiratory depression
Until blood gases can be measured in patients at risk of type II resp failure, initial oxygen should be given using a controlled concentration of ______% or ______%, titrated towards a target oxygen saturation of 88–92% or the level specified on the patient’s oxygen alert card if available
24
28
*The aim is to provide the patient with enough oxygen to achieve an acceptable arterial oxygen tension without worsening carbon dioxide retention and respiratory acidosis
Patients with COPD and other at-risk conditions who have had an episode of hypercapnic respiratory failure, should be given a ______________ and an ______________
24% or 28% Venturi mask
oxygen alert card endorsed with the oxygen saturations required during previous exacerbations
*Patients and their carers should be instructed to show the card to emergency healthcare providers in the event of an exacerbation
Oxygen should only be prescribed for use in the home after ________________
careful evaluation in hospital by respiratory experts
Patients should be advised of the risks of _______________ when receiving oxygen therapy, including the risk of __________
continuing to smoke
fire
_______________ therapy should be recommended before home oxygen prescription
Smoking cessation
In patients with COPD, home oxygen therapy should only be provided if the patient has stopped _______________
Smoking
Some patients with ______________ require supplementary oxygen for air travel. The patient’s requirement should be discussed with the airline before travel
arterial hypoxaemia
Long-term administration of oxygen (usually at least ___________ daily) improves survival in COPD patients with more severe hypoxaemia
15 hours
The need for oxygen should be assessed in COPD patients with which additional features? (6)
- FEV1 less than 30% predicted
- Cyanosis
- Polycythemia
- Peripheral edema
- Raised JVP
- Oxygen sat is 92% or less on air
Assessment for long-term oxygen therapy requires measurement of _____________
arterial blood gas tensions
*Measurements should be taken on 2 occasions at least 3 weeks apart to demonstrate clinical stability
Long-term oxygen therapy should be considered for patients with COPD with PaO2
7.3
Long-term oxygen therapy should be considered for patients with COPD with PaO2 ______ kPa when stable and do not smoke, and also have either secondary polycythaemia, peripheral oedema, or evidence of pulmonary hypertension (minimum of 15 hours per day)
7.3–8
What is the normal range of PaO2 in kPa?
10.5-13.5
What is the normal range of PaCO2 in kPa?
5.1-5.6
Long-term oxygen therapy should be considered for patients with severe chronic asthma with PaO2< _____ kPa or persistent disabling breathlessness
7.3
Long-term oxygen therapy should be considered for patients with interstitial lung disease with PaO2< ___ kPa and in patients with PaO2>___ kPa with disabling dyspnoea
8
8
Long-term oxygen therapy should be considered for patients with cystic fibrosis when PaO2< ____ kPa or if PaO2 ______ kPa in the presence of secondary polycythaemia, nocturnal hypoxaemia, pulmonary hypertension, or peripheral edema
- 3
- 3–8
(Like COPD)
Long-term oxygen therapy should be considered for patients with pulmonary hypertension, without parenchymal lung involvement when PaO2< ____ kPa
8
Long-term oxygen therapy should be considered for patients with neuromuscular or skeletal disorders, after _____________
specialist assessment
Long-term oxygen therapy should be considered for patients with obstructive sleep apnoea despite continuous positive airways pressure therapy, after ______________
Specialist assessment
Long-term oxygen therapy should be considered for patients with ________________ or other terminal disease with disabling dyspnoea
pulmonary malignancy
Long-term oxygen therapy should be considered for patients with heart failure with daytime PaO2< ___ kPa when breathing air or with nocturnal hypoxaemia
7.3
Long-term oxygen therapy should be considered for patients with paediatric respiratory disease, after ______________
specialist assessment
Increased _________________ is seldom a problem in patients with stable respiratory failure treated with low concentrations of oxygen although it may occur during exacerbations
respiratory depression
- patients and relatives should be warned to call for medical help if drowsiness or confusion occur
A risk assessment should be carried out for all COPD patients being considered for long-term oxygen therapy and if treatment is given, should be reviewed at least ___________
annually
Do not offer long-term oxygen therapy to patients who continue to ___________ despite being offered ____________
smoke
smoking cessation interventions
Oxygen is occasionally prescribed for short-burst (intermittent) use for episodes of ______________ in patients with interstitial lung disease, heart failure, and in palliative care
breathlessness not relieved by other treatment
*It is important, however, that the patient does not rely on oxygen instead of obtaining medical help or taking more specific treatment
Short-burst oxygen therapy can be used to improve ______________ and ____________; it should only be continued if there is proven improvement in breathlessness or exercise tolerance
exercise capacity
recovery
Short-burst oxygen therapy is not recommended for COPD patients who have mild or no ______________
hypoxaemia at rest
Ambulatory oxygen is prescribed for patients on long-term oxygen therapy who need _______________
to be away from home on a regular basis
Patients who are not on long-term oxygen therapy can be considered for ambulatory oxygen therapy if there is evidence of ______________________
exercise-induced oxygen desaturation and of improvement in blood oxygen saturation and exercise capacity with oxygen
Ambulatory oxygen therapy is NOT recommended for which patients? (3)
- HF
- COPD with mild or no hypoxemia at rest
- Those who smoke
Under the NHS oxygen may be supplied as _______________
oxygen cylinders
- Oxygen flow can be adjusted as the cylinders are equipped with an oxygen flow meter with ‘medium’ (2 litres/minute) and ‘high’ (4 litres/minute) settings
Oxygen delivered from a cylinder should be passed through a ______________ if used for long periods
humidifier
An ___________________ is recommended for a patient who requires oxygen for more than 8 hours a day (or 21 cylinders per month)
Oxygen concentrator
An oxygen concentrator is recommended for a patient who requires oxygen for more than _____________ hours a day (or 21 cylinders per month)
8
A _______________ is usually preferred for long-term oxygen therapy from an oxygen concentrator
nasal cannula
Nasal cannulae can produce _____________ and ______________ in sensitive individuals
dermatitis
mucosal drying
Giving oxygen by nasal cannula allows the patient to talk, eat, and drink, but the concentration of oxygen is ________________
not controlled
- this may not be appropriate for acute respiratory failure
When oxygen is given through a nasal cannula at a rate of 1–2 litres/minute the inspiratory oxygen concentration is usually ____________, but it varies with ventilation and can be high if the patient is _______________
low
underventilating
https://www.medicinescomplete.com/#/content/bnf/_931070969
What 4 oxygen services may be ordered in England and Wales?
- Emergency oxygen
- Short-burst (intermittent) oxygen
- Long-term oxygen therapy (LTOT)
- Ambulatory oxygen
The type of oxygen service (or combination of services) should be ordered on a Home Oxygen Order Form (HOOF); the amount of oxygen required ( ____________ ) and ____________ should be specified
hours per day
flow rate
What are the steps in the oxygen ladder from lowest oxygen delivery to highest? (7)
- Room air (21% O2)
- Nasal cannula, 1-4 L/min (24-40% O2)
* can be given up to 6 L/min but may cause dryness and discomfort - Venturi; flow rate depends on venturi color (25-60% O2)
- Non-rebreather, 15 L/min (60-90% O2)
- Non-rebreather + LFNC (90-100% O2)
- CPAP, BiPAP or HFNC at 5-60 L/min (up to 100% O2)
- Intubation (100% O2)
What is the oxygen saturation of room air?
21%
What are the oxygen saturation and flow rate of LFNC?
1-4 L/min
(Over 6 causes dryness and discomfort)
24-40% Oxygen saturation
What are the oxygen saturation and flow rates of venturi masks? (6)
24% ——> 2 L/min 28% ——> 4 L/min 31% ——> 6 L/min 35% ——> 8 L/min 40% ——> 10 L/min 60% ——> 15 L/min
What are the flow rate and oxygen saturation of a non-rebreather mask?
15 L/min
60-90% oxygen
What is the flow rate and oxygen saturation of HFNC?
5-60 L/min; up to 100% oxygen
What are the flow rates and oxygen saturations of CPAP and BiPAP?
Up to 100% oxygen saturation
Flow rate up to 25 L/min
