Acute respiratory distress syndrome Flashcards
What is acute respiratory distress syndrome (ARDS)
A form of acute respiratory failure caused by permeability pulmonary oedema resulting from endothelial damage due to a cascade of inflammatory events developing in response to an initiating injury or illness
How does pulmonary odema arise in ARDS
Because of increased alveolar capillary permeability
How does pulmonary oedema arise in most situations
As a result of increased pulmonary capillary pressure (left ventricular failure)
What gives rise to acute lung injury
The systemic inflammatory response
What is a characteristic feature of permeability pulmonary oedema in ARDS
The pulmonary capillary wedge pressure is not elevated
What are direct causes of ARDS development
Aspiration of gastric contents or severe pneumonia or lung contusion
What are indirect causes of ARDS development
Systemic sepesis
Major trauma
pancreatitis
What are the normal features of ARDS
A history of an initiating injury or illness
hypoxaemia refractory to oxygen therapy
Bilateral diffuse infiltrates on CXR
No evidence of cardiogenic pulmonary oedema
What is the treatment of ARDS
Optimal management of the initiating illness or injury combined with supportive care directed at preserving adequate oxygenation, maintaining optimal haemodynamic function and compensating for multiorgan failure
What is the treatment of ARDS
Optimal management of the initiating illness or injury combined with supportive care directed at preserving adequate oxygenation, maintaining optimal haemodynamic function and compensating for multiorgan failure
What is often necessary in ARDS
Endotracheal intubation and mechanical ventilation and transfer to ITU
What does positive pressure ventilation do
Mechanically inflates the lungs delivering oxygen enriched air at a set tidal volume and rate
What is permissive hypercapnia
A technique that allows the patient to have a high PaCO2 level on order to reduce the alveolar ventilation and to avoid excessive airway pressure
What position should the patient be in to reduce gravity dependent fluid deposition and atelectasis
Prone posture
What 2 drugs should be used in ARDS
Diuretics and Vasodilators
