Flashcards in Respiratory Support ✅ Deck (112)
What is respiratory failure defined as?
A syndrome of inadequate gas exchange
What is the result of the inadequate gas exchange in respiratory failure?
Arterial oxygen, carbon dioxide, or both cannot be maintained within their normal ranges
What is the normal oxygen PaO2?
What is the normal carbon dioxide PaCO2?
What is the normal arterial-alveolar oxygen tension difference PA-aO2?
10-25mmHg (in room air)
What is a drop in arterial oxygenation termed?
What is a rise in arterial carbon dioxide levels termed?
What determines the classification of respiratory failure into type I and II?
Absence or presence of hypercapnia respectively
What is type 1 respiratory failure defined as?
Hypoxia without hypercapnia (PaCO2 may be normal or low)
What is type 1 respiratory failure typically caused by?
What is meant by V/Q mismatch?
The volume of air flowing in and out of the lungs is not matched with the flow of blood to the lungs
What categories of conditions can cause type 1 respiratory failure?
- Parenchymal diseases
- Interstitial lung diseases
Give 3 interstitial lung diseases that can cause type 1 respiratory failure?
What kind of shunt can cause type 1 respiratory failure?
Right to left shunt
What is type 2 respiratory failure defined as?
Hypoxia with hypercapnia
What is the mechanism of type 2 respiratory failure?
What are the categories of causes of type 2 respiratory failure?
- Increased airway resistance
- Neurological hypoventilation
- Neuromuscular problems
- Decreased functional residual capacity
Give 3 causes of increased airway resistance
Give 2 causes of neurological hypoventilation
- Drug effects
- Brain stem lesions
Give 2 neuromuscular problems causing type 2 respiratory failure
- Guillain-Barre syndrome
- Congenital myopathy
Give 4 causes of reduced functional residual capacity
- Chest deformity
- Flail chest
What can respiratory failure lead to if untreated?
End organ damage and death from hypoxia
What is the purpose of respiratory support in respiratory failure?
To prevent progression to organ damage and death, and maintain life while the underlying condition is treated
What does respiratory support range from?
Oxygen by face mask, to non-invasive support, endotracheal intubation and mechanical ventilation, and extracorporeal membrane oxygenation (ECMO)
Which children should receive oxygen support?
Children with SpO2 <92% in air
What happens at a SpO2 below 92%?
The oxygen haemoglobin dissociation curve becomes steep, and delivery of oxygen to the tissues becomes compromised
What can high concentration inspired oxygen cause?
Direct cellular toxicity and reabsorption atelectasis
What is the result of both high and low oxygen concentrations being damaging?
The amount of inspired oxygen should be titrated according to pulse oximetry
What does a fixed performance, high flow mask provide?
Fractional inspired oxygen concentration (FiO2) within range of 0.26-0.6