Prognostic value of nitric oxide as a serum biomarker in patients with
ARDS caused by Influenza A H1N1
Background Due to profound morbidity and a high rate of mortality in
patients with acute respiratory distress syndrome (ARDS), identification
of potential biomarkers such as nitric oxide (NO) is important to
determine prognosis and guide clinical decision‐making. Methods and
results: In this study, we included twenty-nine patients admitted to the
Medical Intensive Care Unit diagnosed with ARDS caused by influenza A
(H1N1) whose serum samples were collected on day 1 for determination of
NO levels by GRIESS method. Simplified Acute Physiology Score (SAPS II)
and Acute Physiology and Chronic Health Evaluation II (APACHE II)
scoring were performed on day 1 as well. The mortality in the observed
patients was 55%. SAPS II and APACHE II scores were significantly
higher (p < 0.05) in non-survivors as compared to survivors.
There were no significant differences in gender, age, cigarette smoking
and chronic pulmonary diseases between the survivors and non-survivors.
As compared to non-survivors, the serum levels of NO were significantly
higher in survivors (p < 0.05). Spearman’s rank correlation
analysis indicated a significant positive correlation of SAPS II and
APACHE II with NO. By using serum levels of NO, the receiver operating
characteristic curve was plotted and the provided predictable accuracy
of mortality (outcome) was 96%. Conclusion: The present study showed
that measuring serum levels of NO in patients with ARDS (influenza
A-H1N1) might be useful in predicting the clinical outcome.