Management

Consult expert advice.

Recommended therapies to decrease mortality in ARDS remain limited and include low-tidal volume mechanical ventilation, prone ventilation and recently, the ECMO (extracorporeal membrane oxygenation) rescue therapy in extreme cases (1)

Once the cause has been identified and treated, the aim of treatment is to resuscitate the patient and achieve adequate gas exchange without further exacerbating injury.

Mechanical ventilation is often required using high inspired oxygen, usually for a long time. A positive end-expiratory pressure (PEEP) of 5-15 cm H2O is generally considered helpful to prevent premature alveolar closure. Although PEEP helps with oxygenation, it does so at the expense of cardiac output.

Blood gases should be checked regularly. Inspired oxygen concentrations should be kept to a minimum that will prevent severe hypoxaemia - oxygen toxicity is not a problem if FiO2 is below 50%.

Fluids should be replaced, but with care not to overload. Assessment may be made by measuring blood pressure and and urine output. Finer assessment may be necessary using a Swan Ganz catheter to measure the pulmonary capillary wedge pressure - this reflects the left atrial pressure. Monitoring of central venous pressure is not generally considered appropriate in ARDS.

If there is evidence of circulatory failure despite adequate hydration - such as fall in cardiac or urine output - then consider low dose dopamine as a renal arterial dilator, and dobutamine for its positive inotropic action. If there is fluid overload, consider frusemide 40-120 mg per 24 hours i.v.

Antibiotics should be given if there has been an infective aetiology.

Steroids in ARDS:

• data from clinical trials does not support the use of short-course, high-dose corticosteroids for preventing ARDS or for the treatment of early ARDS (2)
• a systematic review found that the use of low-dose corticosteroids was associated with improved mortality and morbidity outcomes without increased adverse reactions (3)

Reference:

• Rawal G, Yadav S, Kumar R. Acute Respiratory Distress Syndrome: An Update and Review. J Transl Int Med. 2018;6(2):74-77. Published 2018 Jun 26. doi:10.1515/jtim-2016-0012
• Deal EN et al.Role of corticosteroids in the management of acute respiratory distress syndrome. Clinical Therapeutics 2008;30(5): 787-799.
• Tang BM et al. Use of corticosteroids in acute lung injury and acute respiratory distress syndrome: a systematic review and meta-analysis. Crit Care Med. 2009 May;37(5):1594-603.