ARDS (3) Flashcards
What are the main benefits of ECMO?
- Promote recovery
- Prevention of VILI
What is the characteristic of VILI?
- Volutrauma
- Barotrauma
- Atelectrauma
- Biotrauma
What is the ideal driving pressures?
< 15 cmH2O
What is driving pressure?
This is tidal distending force applied to the alveoli
Veno-venous ECMO is recommended for ?
Severe hypoxaemia and hypercapnia in patients with ARDS
What are the common VV-ECMO configurations?
- Femoral (drainage) - Internal Jugular (return)
- Bicaval dual lumenn cannula (Superior & Inferior vena cava drainage with RA return)
- Femoral (drainage) - Contralateral femoral (return)
What are the common modes of ECMO in the presence of cardiogenic shock?
- Veno-pulmonary arterial
- Veno-arterial
- Veno-veno-arterial
The highly oxygenated blood delivered from the ECLS circuit does what to HPV
It reverses hypoxic pulmonary vasoconstriction.
Increases ventilation to poorly ventilated lung units
Initial sweep gas flow setting on ECMO?
A low sweep gas flow is used to prevent rapid correction of pH and CO2
What is the main complication of high sweep gas flow in ECMO?
Ischaemic complication of cerebral vasoconstriction
What is the main pathophysiological characteristic of obstructive lung disease exacerbation ?
- Expiratory flow limitation
- Increased small airway resistance
What is the main causes of increased work of breathing in patients with exacerbation of obstructive lung disease?
- Dynamic alveolar hyperinflation
- Intrinsic PEEP
What are the relative contraindications to ECMO?
- Septic shock
- MOF
- Severe arterial occlusive disease
- Heparin induced thrombocytopenia
- Long duration of ventilation
- Advanced age
ECMO configuration?
What is the delivery rate of VA-ECMO?
2-6L of oxygenated blood
What is the indication for VA-ECMO?
Cardiogenic shock
What is ARDS?
It is an acute inflammatory lung pathology and it is not a disease as it is always precipitated by an underlying cause.
ARDS can be classified into ?
- Pulmonary
- Extrapulmonary
What is the mechanism of pulmonary ARDS?
- Direct insult to the lung
- Damage to alveolar epithelium
What is the mechanism of extrapulmonary ARDS?
- Indirect insult to the lung
- Inflammatory mediators responsible
- Inflammatory mediators act upon vascular endo
What are the causes of pulmonary ARDS?
- Pneumonia (60%)
- Aspiration
- Inhalation injury
- Pulmonary contusion
- Pulmonary vasculitis
- Near drowning
What are the causes of extra-pulmonary ARDS?
- Non-pulmonary sepsis
- Non-cardiogenic shock
- Pancreatitis
- Trauma
- Blood transfusion
- Severe burns
- Drug OD
Characteristics of ARDS?
- Respiratory symptoms within 7 days of insult
- Disease progression after several weeks
- Fibrosis, pneumonia & granulomatosis
