ARDS Flashcards
what may it be caused by
direct lung injury or secondary to systemic illness
what is the pathology
lung damage and release inflame mediators cause incr capillary permeability and non cardiogenic pulm oedema, multiorgan failure
pulmonary causes
pneumonia, gastric aspiration, inhalation, injury, vasculitis, contusion
other causes
shock, septicaemia, haemorrhage, multiple transfusions, DIC, pancreatitis, acute liver failure, trauma, head injury, malaria, fat embolism, burns, drugs/toxins, obstetric events
clinical features
cyanosis, tachypnoea, tachycardia, peripheral vasodilatation, bilat fine inspiratory crackles
investigations
FBC, U&E, LFT, amylase, clotting, CRP, cultures, ABG. CXR- bilat pulmonary infiltrates.
what is a pulmonary artery catheter used to measure
pulmonary capillary wedge pressure
diagnostic criteria
- acute onset. 2. CXR- bilat infiltrates. 3- PCWP <19mmHg or a lack of clinical CCF. 4. refractory hypoxaemia
management
admit to ITU, supportive therapy.
what respiratory support
CPAP with 40-60% O2. mechanical ventilation. want low tida vol, pressure limited approach with low or moderate high positive end expiratory pressure (if large tidal vol then at risk of pneumothorax)
what circulatory support
circulatory- arterial line and Swan-Ganz catheter- monitor PCWP and cardiac output. fluids. inotropes to maintain cardiac output and O2 delivery eg dobutamine, vasodilators, transfusion.
what could you treat pulmonary hypertension with
NO, pulmonary vasodilator
management sepsis
identify organisms and treat, avoid nephrotoxic antibiotics
other management
nutritional support- enteral- high fat, antioxidant formulations. steroids protect those at risk of fat embolization and with pneumocystosis, may improve subacute ARDS.
when is the prognosis worse
age of patient, cause of ARDS (pneumonia worse than trauma eg), if >3 organs involved for >1 week then invariable fatal
