Respiratory failure Flashcards
What are tachypnoea, use of accessory muscles, nasal flaring, and intercostal/suprasternal recession all signs of?
Respiratory compensation during respiratory failure
What are tachycardia, hypertension and sweating all signs of in respiratory failure?
increased sympathetic tone
What are altered mental state, bradycardia and hypotension all signs of in respiratory failure?
End organ hypoxia
In respiratory failure, what is cyanosis a sign of?
Haemoglobin desaturation
What are flapping wrists and a bounding pulse a sign of?
CO2 retention
What would material blood gases in Type I respiratory failure show?
Hypoxaemia and normocapnia
What is the PaO2 in Type I respiratory failure?
<8 kPa
In which conditions does Type I respiratory failure normally occur?
COPD
Pneumonia
Asthma
Pulmonary fibrosis
Why does Type I respiratory failure occur?
- Damage to lung tissue
- prevents adequate oxygenation of blood
- remaining normal lung is sufficient to excrete CO2 produced via metabolism
- -> less functioning lung tissue is needed for CO2 excretion compared to oxygenation of blood
What would material blood gases in Type II respiratory failure show?
hypoxaemia and hypercapnia
What is the PaO2 and PaCO2 in Type II respiratory failure?
PaO2: <8 kPa
PaCO2: >6.5 kPa
*basically is it type I respiratory failure but with fatigue
In which conditions does Type II respiratory failure normally occur?
COPD
Severe asthma
Drug overdose
Poisoning
Why does Type II respiratory failure occur?
- when alveolar ventilation is insufficient to excrete CO2 produced
- inadequate ventilation is due to reduced ventilatory effort (inability to overcome increased resistance to ventilation)
- CO2 is able to accumulate as the whole lung is affected
What are the complications of respiratory failure?
Damage to vital organs CNS depression (due to increased CO2) Respiratory acidosis (CO2 retention)
What are the causes of hypoventilation?
Respiratory muscles
Airway obstruction
Reduced lung/chest wall compliance
Damage to brainstem/spinal cord
How is respiratory failure treated?
- supplemental O2 (facemask)
- control of secretion (physiotherapy)
- treatment of infection (abx)
- control of airways obstruction (bronchodilators, corticosteroids)
- limiting pulmonary oedema
- reducing load on respiratory muscles
When should an O2 mask with nasal cannula be used?
for patients with normal vital signs (post-op)
When should a face mask with reservoir bags be used?
patient in emergency (higher O2 concentration)
–> asthma attack, pneumonia, sepsis
When should a venturi mask be used?
controlled treatment in long-term respiratory failure (COPD)
What should be done for a patient with respiratory failure who does not show signs of CO2 retention?
Start high flow of O2
Monitor for drowsiness
Check ABG after 30 minutes
What should be done for a patient with respiratory failure who does show signs of CO2 retention?
Set up a controlled mask
Titrate for lowest possible O2
Measure ABG ASAP
Repeat ABG 30 minutes later
When is ventilation used?
Used for hypercapnia, not hypoxia**
