Objectives

In pediatric acute respiratory distress syndrome, lung injury is mediated by immune activation and severe inflammation. Therefore, we hypothesized that patients with elevated pro- and anti-inflammatory cytokines would have higher mortality rates and that these biomarkers could improve risk stratification of poor outcomes.

Design

Multicenter prospective observational study.

Setting

We enrolled patients from five academic PICUs between 2008 and 2015.

Patients

Patients were 1 month to 18 years old, used noninvasive or invasive ventilation, and met the American European Consensus Conference definition of acute respiratory distress syndrome.

Interventions

Eight proinflammatory and anti-inflammatory cytokines were measured on acute respiratory distress syndrome day 1 and correlated with mortality, ICU morbidity as measured by survivor Pediatric Logistic Organ Dysfunction score, and biomarkers of endothelial injury, including angiopoietin-2, von Willebrand Factor, and soluble thrombomodulin.

Measurements and main results

We measured biomarker levels in 194 patients, including 38 acute respiratory distress syndrome nonsurvivors. Interleukin-6, interleukin-8, interleukin-10, interleukin-18, and tumor necrosis factor-R2 were each strongly associated with all-cause mortality, multiple markers of ICU morbidity, and endothelial injury. A multiple logistic regression model incorporating oxygenation index, interleukin-8, and tumor necrosis factor-R2 was superior to a model of oxygenation index alone in predicting the composite outcome of mortality or severe morbidity (area under the receiver operating characteristic, 0.77 [0.70-0.83] vs 0.70 [0.62-0.77]; p = 0.042).

Conclusions

In pediatric acute respiratory distress syndrome, pro- and anti-inflammatory cytokines are strongly associated with mortality, ICU morbidity, and biochemical evidence of endothelial injury. These cytokines significantly improve the ability of the oxygenation index to discriminate risk of mortality or severe morbidity and may allow for identification and enrollment of high-risk subgroups for future studies.

Objectives

To determine the feasibility of pulmonary function and quality of life evaluations in children after acute respiratory distress syndrome.

Design

A prospective follow-up feasibility study.

Setting

A tertiary PICU.

Patients

Children less than 18 years old with acute respiratory distress syndrome admitted between 2000 and 2005.

Intervention

Pulmonary function testing and patient and parental quality of life surveys approximately 12-month after acute respiratory distress syndrome.

Measurements and main results

One hundred eighty patients met acute respiratory distress syndrome criteria; 37 (20%) died, 90 (51%) declined participation, 28 (16%) consented but did not return, and 24 (13%) returned for follow-up visit. Twenty-three patients completed quality of life testing and 17 completed pulmonary functions. Clinical characteristics of those who returned were no different from those who did not except for age (median age, 4.9 vs 1.8 yr). One-third had mild to moderate pulmonary function deficits. Quality of life scores were marginal with general health perception, physical functioning, and behavior being areas of concern. These scores were lower than scores in children with chronic asthma. Parental quality of life assessments report lower scores in single-parent homes but no differences were noted by race or parental employment status.

Conclusions

Valuable information may be discerned from acute respiratory distress syndrome patients who return for follow-up evaluation. In this pilot study, up to one-third of children with acute respiratory distress syndrome exhibit pulmonary function deficits and 12-month postillness quality of life scores are lower than in children with chronic asthma. Parental perceptions of postillness quality of life may be negatively impacted by socioeconomic constraints. Long-term follow of children with acute respiratory distress syndrome is feasible and bears further investigation.

Objectives

As acute kidney injury and elevated cumulative fluid balance commonly co-occur in pediatric acute respiratory distress syndrome, we aimed to identify risk factors for their development and evaluate their independent relationships with mortality. We hypothesized that acute kidney injury and elevated cumulative fluid balance would be associated with markers of inflammation and that children with elevated cumulative fluid balance and concomitant acute kidney injury would have worse outcomes than other children.

Design

Prospective observational study using the pediatric Risk, Injury, Failure, Loss, End-Stage acute kidney injury classification.

Setting

Five academic PICUs.

Patients

Two-hundred sixty patients 1 month to 18 years old meeting the Berlin definition of acute respiratory distress syndrome between 2008 and 2014.

Interventions

None.

Measurements and results

PICU mortality was 13% (34/260). Relative to survivors, nonsurvivors had greater cumulative fluid balance on day 3 of acute respiratory distress syndrome (+90.1 mL/kg; interquartile range 26.6-161.7 vs +44.9 mL/kg; interquartile range 10.0-111.3; p = 0.008) and also had higher prevalence of acute kidney injury on day 3 of acute respiratory distress syndrome (50% vs 23%; p = 0.001). On stratified analysis, greater cumulative fluid balance on day 3 of acute respiratory distress syndrome was associated with mortality among patients with concomitant acute kidney injury (+111.5 mL/kg for nonsurvivors; interquartile range 82.6-236.8 vs +58.5 mL/kg for survivors; interquartile range 0.9-176.2; p = 0.041) but not among patients without acute kidney injury (p = 0.308). The presence of acute kidney injury on acute respiratory distress syndrome day 3 was associated with mortality among patients with positive cumulative fluid balance (29.1% vs 10.4% mortality; p = 0.001) but not among patients with even or negative cumulative fluid balance (p = 0.430). Day 1 plasma interleukin-6 levels were associated with the development of day 3 positive cumulative fluid balance, day 3 acute kidney injury, and PICU mortality and the association between elevated day 1 interleukin-6 and PICU mortality was partially mediated by the interval development of day 3 positive cumulative fluid balance and day 3 acute kidney injury (p < 0.001).

Conclusions

In pediatric acute respiratory distress syndrome, elevated cumulative fluid balance on day 3 of acute respiratory distress syndrome is associated with mortality specifically in patients with concomitant acute kidney injury. Plasma interleukin-6 levels are associated with the development of positive cumulative fluid balance and acute kidney injury, suggesting a potential mechanism by which inflammation might predispose to mortality.

Objectives

Despite declining mortality, acute respiratory distress syndrome is still involved in up to one third of pediatric intensive care deaths. The recently convened Pediatric Acute Lung Injury Consensus Conference has outlined research priorities for the field, which include the need for accurate bedside risk stratification of patients. We aimed to develop a simple yet robust model of mortality risk among pediatric patients with acute respiratory distress syndrome to facilitate the targeted application of high-risk investigational therapies and stratification for enrollment in clinical trials.

Design

Prospective, multicenter cohort.

Setting

Five academic PICUs.

Patients

Three hundred eight children greater than 1 month and less than or equal to 18 years old, admitted to the ICU, with bilateral infiltrates on chest radiograph and PaO2/FIO2 ratio less than 300 in the clinical absence of left atrial hypertension.

Interventions

None.

Measurements and main results

Twenty clinical variables were recorded in the following six categories: demographics, medical history, oxygenation, ventilation, radiographic imaging, and multiple organ dysfunction. Data were measured 0-24 and 48-72 hours after acute respiratory distress syndrome onset (day 1 and 3) and examined for associations with hospital mortality. Among 308 enrolled patients, mortality was 17%. Children with a history of cancer and/or hematopoietic stem cell transplant had higher mortality (47% vs 11%; p < 0.001). Oxygenation index, the PaO2/FIO2 ratio, extrapulmonary organ dysfunction, Pediatric Risk of Mortality-3, and positive cumulative fluid balance were each associated with mortality. Using two statistical approaches, we found that a parsimonious model of mortality risk using only oxygenation index and cancer/hematopoietic stem cell transplant history performed as well as other more complex models that required additional variables.

Conclusions

In the PICU, oxygenation index and cancer/hematopoietic stem cell transplant history can be used on acute respiratory distress syndrome day 1 or day 3 to predict hospital mortality without the need for more complex models. These findings may simplify risk assessment for clinical trials, counseling families, and high-risk interventions such as extracorporeal life support.