Jeanette M. Asselin

Clinical prediction models for bronchopulmonary dysplasia: a systematic review and external validation study

BackgroundBronchopulmonary dysplasia (BPD) is a common complication of preterm birth. Very different models using clinical parameters at an early postnatal age to predict BPD have been developed with little extensive quantitative validation. The objective of this study is to review and validate clinical prediction models for BPD.MethodsWe searched the main electronic databases and abstracts from annual meetings. The STROBE instrument was used to assess the methodological quality. External validation of the retrieved models was performed using an individual patient dataset of 3229 patients at risk for BPD. Receiver operating characteristic curves were used to assess discrimination for each model by calculating the area under the curve (AUC). Calibration was assessed for the best discriminating models by visually comparing predicted and observed BPD probabilities.ResultsWe identified 26 clinical prediction models for BPD. Although the STROBE instrument judged the quality from moderate to excellent, only four models utilised external validation and none presented calibration of the predictive value. For 19 prediction models with variables matched to our dataset, the AUCs ranged from 0.50 to 0.76 for the outcome BPD. Only two of the five best discriminating models showed good calibration.ConclusionsExternal validation demonstrates that, except for two promising models, most existing clinical prediction models are poor to moderate predictors for BPD. To improve the predictive accuracy and identify preterm infants for future intervention studies aiming to reduce the risk of BPD, additional variables are required. Subsequently, that model should be externally validated using a proper impact analysis before its clinical implementation.

Randomized Controlled Trial of a Breath-Actuated Nebulizer in Pediatric Asthma Patients in the Emergency Department

BACKGROUND: Bronchodilator treatment for asthma can be provided with various aerosol-generating devices and methods. There have been no randomized trials of a breath-actuated nebulizer versus continuous 1-hour nebulization and/or small-volume constant-output nebulizer in pediatric asthma patients. METHODS: We conducted a randomized study of one-time albuterol treatment with the AeroEclipse breath-actuated nebulizer versus standard therapy (single treatment via small-volume nebulizer or 1-hour of continuous nebulized albuterol) in pediatric asthma patients in the emergency department. Eligible patients were those admitted to the emergency department, 0 months to 18 years of age, who presented with asthma or wheezing. We assessed all the patients with our clinical asthma scoring system and peak-flow measurement if possible. We stratified the patients by clinical asthma score and weight, and then randomized them to receive their initial albuterol treatment in the emergency department via either AeroEclipse or standard therapy. We recorded time in the emergency department, change in clinical asthma score, need for additional bronchodilator treatments, need for admission, patient response, ability to actuate the AeroEclipse, and adverse effects. RESULTS: We enrolled 149 patients between October 14, 2004 and November 11, 2005, and we randomized 84 patients to AeroEclipse and 65 to standard therapy. The cohorts average age was 5.5 years. There were no significant differences in demographics. The initial mean clinical asthma scores were 5.1 ± 2.4 in the AeroEclipse group, and 5.1 ± 2.1 in the standard-therapy group. Time in the emergency department was not different (AeroEclipse 102 min, standard therapy 125 min, P = .10), but the AeroEclipse group had a significantly greater improvement in clinical asthma score (1.9 ± 1.2 vs 1.2 ± 1.4, P = .001) and respiratory rate (P = .002), and significantly lower admission rate (38% vs 57%, P = .03). There was no difference in adverse effects. CONCLUSIONS: Although AeroEclipse did not reduce the time in the ED, it significantly improved clinical asthma score, decreased admissions, and decreased respiratory rate.

Early Cumulative Supplemental Oxygen Predicts Bronchopulmonary Dysplasia in High Risk Extremely Low Gestational Age Newborns.

OBJECTIVE To assess the prognostic accuracy of early cumulative supplemental oxygen (CSO) exposure for prediction of bronchopulmonary dysplasia (BPD) or death, and to evaluate the independent association of CSO with BPD or death. STUDY DESIGN We performed a secondary analysis of the Trial of Late Surfactant, which enrolled 511 infants born at ≤28 weeks gestational age who were mechanically ventilated at 7-14 days of life. Our primary outcome was BPD or death at 36 weeks postmenstrual age, as determined by a physiological oxygen/flow challenge. Average daily supplemental oxygen (fraction of inspired oxygen - 0.21) was calculated. CSO was calculated as the sum of the average daily supplemental oxygen over time periods of interest up to 28 days of age. Area under the receiver operating curve (AUROC) values were generated to evaluate the accuracy of CSO for prediction of BPD or death. The independent relationship between CSO and BPD or death was assessed in multivariate modeling, while adjusting for mean airway pressure. RESULTS In the study infants, mean gestational age at birth was 25.2 ± 1.2 weeks and mean birth weight was 700 ± 165 g. The AUROC value for CSO at 14 days was significantly better than that at earlier time points for outcome prediction (OR, 0.70; 95% CI, 0.65-0.74); it did not increase with the addition of later data. In multivariate modeling, a CSO increase of 1 at 14 days increased the odds of BPD or death (OR, 1.7; 95% CI, 1.3-2.2; P < .0001), which corresponds to a 7% higher daily supplemental oxygen value. CONCLUSION In high-risk extremely low gestational age newborns, the predictive accuracy of CSO plateaus at 14 days. CSO is independently associated with BPD or death. This index may identify infants who could benefit from early intervention to prevent BPD.

High surgical burden for infants with severe chronic lung disease (sCLD)

BACKGROUND/PURPOSE Infants with severe chronic lung disease (sCLD) may require surgical procedures to manage their medical problems; however, the scope of these interventions is undefined. The purpose of this study was to characterize the frequency, type, and timing of operative interventions performed in hospitalized infants with sCLD. METHODS The Childrens Hospital Neonatal Database was used to identify infants with sCLD from 24 childrens hospitals NICUs hospitalized over a recent 16-month period. RESULTS 556 infants were diagnosed with sCLD; less than 3% of infants had operations prior to referral and 30% were referred for surgical evaluation. In contrast, 71% of all sCLD infants received ≥1 surgical procedure during the CHND NICU hospitalization, with a mean of 3 operations performed per infant. Gastrostomy insertion (24%), fundoplication (11%), herniorrhaphy (13%), and tracheostomy placement (12%) were the most commonly performed operations. The timing of gastrostomy (PMA 48±10 wk) and tracheostomy (PMA 47±7 wk) insertions varied, and for infants who received both devices, only 33% were inserted concurrently (13/40 infants). CONCLUSIONS A striking majority of infants with sCLD received multiple surgical procedures during hospitalizations at participating NICUs. Further work regarding the timing, coordination, perioperative complications, and clinical outcomes for these infants is warranted.

O-022 Treatment Of Ventilated Preterm (pt) Infants With Late Surfactant Does Not Increase Survival Without Bronchopulmonary Dyplasia(bpd) At 36 Wk Pma

Background/aims The pathogenesis of BPD is multifactorial. In preterm infants ≤28 wk GA requiring ventilation at 7–14 days, >60% have surfactant dysfunction. Survival without BPD in these infants is <25%. Inhaled nitric oxide (iNO) may improve outcome in some infants (Schreiber, NEJM 2003, Ballard NEJM, 2006). Methods Preterm infants ≤28 wk GA requiring mechanical ventilation at 7–14 days were enrolled in a RCT at 25 US centres. All infants received iNO and were randomised to receive surfactant (Infasurf) or sham instillation behind a screen every 1–2 days; maximum of 5 doses. Infants were evaluated by physiologic oxygen/flow reduction at 36 and 40 wk. Pulmonary outcome to 18 months is being collected. Results Between January 2010 and September 2013, 511 of the planned 524 infants were enrolled. There was no difference between groups in mean BW (701 ± 164 grams), GA (25.2 ± 1.2 wk), percentage under 26 wk (70.6%), race, gender, severity of disease at enrollment or co-morbidities of prematurity. Survival without BPD was not different between treated vs. controls at 36 wk (31.3% vs.31.7%; relative benefit 0.98 (0.75, 1.28 p = 0.89) or 40 wk (58.7% vs. 54.1%; relative benefit 1.08 (0.92, 1.27 p = 0.33). Overall survival without BPD at 36wk in African Americans was better than whites (37.2% vs. 25.4%p = 0.008). Conclusions Late treatment with surfactant in ventilated preterm infants did not improve survival without BPD at 36 or 40 weeks PMA. Overall better outcome in African-American infants may be due to a racial response to iNO. Pulmonary and neurodevelopmental assessment are on-going.