ARDS

Question 1

What is ARDS

Answer 1

Acute resp distress syndrome or acute lung injury
Lung damage + inflammatory mediator release increase capillary permeability so non-cardiac pulmonary oedema
Often multiorgan failure as well

Question 2

ARDS causes

Answer 2

Pneumonia
Smoke inhalation
Gastric aspiration

Vasculitis
Acute liver failure

Shock
Sepsis

Question 3

ARDS clinical features

Answer 3

Cyanosis
Tachypnoea + tachcardia
Bilateral fine inspiratory crackles
Peripheral vasodilation

Question 4

ARDS investigations

Answer 4

CXR shows bilateral pulmonary infiltrates

Pulmonary artery catheter to measure pulmonary capillary wedge pressure

Question 5

ARDS diagnostic criteria

Answer 5

Acute onset
CXR bilateral infiltrates
PCWP<19 or lack of CHF
Refractory hypoxaemia with PaO2:FiO2<200 (hypoxia despite o2 therapy)

Question 6

ARDS management

Answer 6

ITU admission, treat underlying cause

Resp support
Circulatory support - Swan-Ganz catheter and art line; maintain CO with inotropes (dobutamine 2.5-10µg/kg/min IVI) + O2 and consider low dose NO for pulmonary HT

Sepsis treatment
Nutritional support

Question 7

ARDS prognosis

Answer 7

50-75% mortality

Prognosis varies with cause, age, no. of organs involved

Question 8

ARDS management - Resp support

Answer 8

CPAP

If PaO2 <8.3 despite 60% O2 and PaCO2>6 then mechanical ventilation

Question 9

ARDS management - Circulatory support

Answer 9

Swan-Ganz catheter and art line and monitor PCWP
Maintain CO with inotropes (dobutamine 2.5-10µg/kg/min IVI) + O2
Consider low dose NO for pulmonary HT