Higher urine nitric oxide is associated with improved outcomes in patients with acute lung injury.

Abstract

RATIONALE:

Nitrogen oxide (NO) species are markers for oxidative stress that may be pathogenic in acute lung injury (ALI).

OBJECTIVES:

We tested two hypotheses in patients with ALI: (1) higher levels of urine NO would be associated with worse clinical outcomes, and (2) ventilation with lower VT would reduce urine NO as a result of less stretch injury.

METHODS:

Urine NO levels were measured by chemiluminescence in 566 patients enrolled in the National Heart Lung and Blood Institute Acute Respiratory Distress Syndrome Network trial of 6 ml/kg versus 12 ml/kg VT ventilation. The data were expressed corrected and uncorrected for urine creatinine (Cr).

RESULTS:

Higher baseline levels of urine NO to Cr were associated with lower mortality (odds ratio, 0.43 per log(10) increase in the ratio), more ventilator-free days (mean increase, 1.9 d), and more organ-failure-free days (mean increase, 2.3 d) on multivariate analysis (p < 0.05 for all analyses). Similar results were obtained using urine NO alone. NO to Cr levels were higher on Day 3 in the 6 ml/kg than in the 12 ml/kg VT group (p = 0.04).

CONCLUSIONS:

Contrary to our hypothesis, higher urine NO was associated with improved outcomes in ALI at baseline and after treatment with the 6 ml/kg VT strategy. Higher endogenous NO may reflect less severe lung injury and better preservation of the pulmonary and systemic endothelium or may serve a protective function in patients with ALI.

• Authors: Dana E McClintock, Lorraine B Ware, Mark D Eisner, Nancy Wickersham, B Taylor Thompson, Michael A Matthay, National Heart, Lung, and Blood Institute ARDS Network
• Journal: American journal of respiratory and critical care medicine (Am J Respir Crit Care Med) Vol. 175 Issue 3 Pg. 256-62 (Feb 01 2007) ISSN: 1073-449X [Print] United States
• PMID: 17082495 (Publication Type: Journal Article, Multicenter Study, Research Support, N.I.H., Extramural)

Chemical References

• Biomarkers
• Nitric Oxide
• Creatinine

Topics

• Adult
• Aged
• Biomarkers
• Creatinine (urine)
• Disease Susceptibility
• Female
• Humans
• Male
• Middle Aged
• Multivariate Analysis
• Nitric Oxide (urine)
• Outcome Assessment, Health Care
• Oxidative Stress
• Prognosis
• Respiratory Distress Syndrome (diagnosis, mortality, urine)
• Severity of Illness Index