PURPOSE: Clarify the indication,timing and dosage of steroid used in ARDS due to viral pneumonia.
Pulsed methylprednisolone dosage should be 0.5-1g daily.
METHODS: By literature review on papers on viral pneumonia, including influenza and SARS coronavirus pneumonia from 2001 to 2011,the indication and the correct steroid usage in ARDS is summarized. P<0.05 is clinically significant.Descriptive studies is included in SARS scenario.
RESULTS: In viral pneumonia, steroid decreases the cytokines, but prolongs vthe viral replication period. Beneficial effect is shown in varicella pneumonia with decreased hospital stay,but in H1N1infected patients, a trend of increasing hospital-acquired pneumonia!, duration of mechanical ventilation, and hospital mortality,especially in patients receiving early steroid therapy.Case studies showed corticosteroid in severe flu pneumonia is beneficial in organizing pneumonia,post-viral inflammatory pneumonitis and H1N1 pneumonia in pregnant women.In SARS,nasopharyngeal aspirate reviewed viral load peaked at 10 days(early viral phase) from symptom onset.The late excessive inflammatory response started 8-14 days from onset with raised IL6,8,16,TNF alpha. Steroid usage should be given by D7 for ARDS, 1day before the late inflammatory response phase.High-dose steroid was associated with aspergillosis,avascular necrosis,myopathy and polyneuropathy.No difference in outcome was observed between patients receiving immunoglobulin/methylprednisolone versus no agents in Singapore study.Pulsed methylprednisolone dosage was 0.5-1g/d,that is compatible to the dosage used in rheumatological diseases(1g/d for 3d).
CONCLUSIONS: Pulsed methylprednisolone is given in the late immune-mediated phase as guided by the nasopharyngeal aspirate result and blood cytokine levels,in a dose of 0.5-1g/d intravenously.
CLINICAL IMPLICATIONS: Methylprednisolone more than 1g/d merely clears up the lung shadows quickly,but invites avascular necrosis later without change in mortality.