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