18.) Respiratory Failure Flashcards
(12 cards)
What is acute respiratory failure?
Acute respiratory failure is characterized by inadequate oxygenation and/or ventilation, defined by hypoxia and hypercapnia.
Hypoxia <80mmhg
Hypercapnia > 45mmhg
What are the causes of acute respiratory failure?
Causes include CNS depression (drug overdose), neuromuscular diseases (myasthenia gravis), upper airway obstruction, thoracic restrictions, cardiovascular issues (congestive heart failure), and lung diseases (asthma, COPD).
What are the types of acute respiratory failure?
- Hypoxemic (Type I): Low oxygen with normal or low carbon dioxide, caused by ventilation/perfusion mismatch.
- Hypercapnic (Type II): Low oxygen and high carbon dioxide, caused by inadequate alveolar ventilation.
What is hypoxemic respiratory failure?
Hypoxemic respiratory failure (Type I) is characterized by low oxygen levels with normal or low carbon dioxide, often due to lung diseases like ARDS or severe pneumonia.
What is hypercapnic respiratory failure?
Hypercapnic respiratory failure (Type II) is characterized by low oxygen and high carbon dioxide, often due to inadequate alveolar ventilation from lung diseases, neuromuscular diseases, or CNS depression.
What are the pathophysiological mechanisms of respiratory failure?
- Ventilation/perfusion mismatch.
- Shunting.
- Hypoventilation.
- Increased CO2 production.
- Diffusion impairment.
What are common symptoms of respiratory failure?
Common symptoms include dyspnea (often first) and sometimes cough depending on the cause.
What are signs of respiratory failure?
Signs include inability to speak in full sentences, use of accessory respiratory muscles, tachypnea, tachycardia, cyanosis, fatigue, hypercapnia, or CNS depression.
How is respiratory failure diagnosed?
Diagnosis includes arterial blood gas analysis, X-ray/CT-scan, CBC and metabolic panel, and considering cardiac enzymes if cardiogenic pulmonary edema is suspected.
What is the management for Type I respiratory failure?
Management includes treating the underlying cause, administering oxygen (35–60% via facemask), and providing assisted ventilation if PaO2 remains under 8kPa despite 60% oxygen.
What is the management for Type II respiratory failure?
Management includes treating the underlying cause, starting controlled oxygen therapy at 24% O2, adjusting oxygen concentration based on ABG results, and considering assisted ventilation if PaCO2 rises above 1.5kPa.
Use bipap
What additional treatments may be considered for Type II respiratory failure?
Additional treatments may include using respiratory stimulants (doxapram) if needed and considering intubation and ventilation if other measures fail.
Doxapram = stimulates the respiratory center in the brain to increase breathing rate and depth.
