2003 OPEN FORUM Abstracts
Nitric Oxide Administration in Pediatric Acute Respiratory Distress Syndrome: AN InterIm Analysis
Shawn Colborn RRT-NPS, Richard Lin MD, Rodolfo I Godinez MD, Marye Godinez MD, Barbara Francis RRT-NPS, Roberta Hales RRT-NPS, RN, Theresa Schultz RRT-NPS, RN. The Children's Hospital of Philadelphia, Pediatric Intensive Care Unit, Philadelphia, Pennsylvania 19104
Background: The literature is mixed as to whether Nitric Oxide (NO) can be useful in the management of Acute Respiratory Distress Syndrome (ARDS), where many of the therapies used are supportive and intended to reduce secondary injury. We report on interim results from a randomized crossover trial looking at the effectiveness of NO in improving oxygenation in pediatric ARDS patients.
Methods: The primary aim of this trial is to demonstrate whether NO produces a clinically significant improvement in oxygenation in patients with pediatric ARDS, defined as a 20% improvement in the PaO2/FiO2 (P/F) ratio. Patients are eligible if they have a clinical diagnosis of ARDS, are intubated, have a P/F ratio of ≤100, and a Murray score of > 2.5. Patients receive a 4-hour block of therapy with 10 ppm NO and a 4-hour block of therapy with 0 ppm NO (control). The order of the blocks was randomized. Data collected includes hourly arterial blood gases, ventilator, and hemodynamic information as well as demographic, diagnostic, and outcome information. We continue to follow patients after the initial 8-hour trial phase. The preliminary data analysis was done using Wilcoxon signed-rank testing
RESULTS: The target enrollment is 54 patients. Thus far, 29 have been enrolled. 3 patients were withdrawn. 12 patients have been randomized to receive NO first and 14 to receive nothing first. The group receiving NO first is similar to the other in terms of gender (both 50% male), mean age (125 vs 111 months), and mean Murray Score (3.17 vs 3.38). In the "NO first" group, the median P/F ratios went from a baseline of 70.5 to 110 after the NO block, and to 98 after both blocks. The change in P/F between the baseline to the NO block value is a 56% increase (p=0.004). In the "nothing first" group, the median P/F went from a baseline of 84.5 to 93 after the control block, and to 102 after both blocks. The change in P/F after each block is a 10% increase. Only the change after both blocks approaches significance (p=0.059)
Conclusions: NO seems to reproducibly improve oxygenation in some patients with pediatric ARDS. It is interesting that the median P/F ratios in patients who receive NO first do not return to baseline values after their control block of therapy (p=0.002). This may be some effect of persistent improvement by NO or represent confounding by some other change which might cause improvement of oxygenation over the course of our study phase (e.g., increase in PEEP). Further analysis is needed. When our study is complete, we might have a better sense of what ARDS subpopulation is responsive to NO and have enough information to design a multi-center trial, which will be needed to assess whether NO has any impact on mortality in pediatric ARDS.