Differences in mortality characteristics in neonates with Down's syndrome

OBJECTIVE

Neonates with Down's syndrome (nDS) may have multiple medical issues that place them at increased risk for mortality during the newborn period. Goal of this study was to determine if there are differences in baseline characteristics, medical complications or procedures performed during hospitalization between nDS who survived versus those who died during initial hospitalization.

STUDY DESIGN

Data from 2000 to 2014 were reviewed using the Pediatric Health Information Systems (PHIS) database on all DS patients admitted to the hospital <30 days postnatal life. Baseline demographics, medical complications, procedures performed and mortality were recorded. Patients were divided into nDS patients who were discharged alive (nDS-a) versus nDS patients who died (nDS-d). Multivariate logistic analysis with odds ratios was performed to determine significant predictors of death. A P<0.05 was considered significant.

RESULTS

A total of 5737 nDS were evaluated. Overall mortality was 7.5% (431/5737). nDS-d were more likely than nDS-a to have a lower birth weight (1.0 (0.9 to 1.0)), presence of a diaphragmatic hernia (6.9 (1.9 to 25.1), or a cardiac diagnosis of a pulmonary venous abnormality (6.8 (1.9 to 24.4)), Ebstein's anomaly (3.2 (1.2 to 8.5)) or left-sided obstructive lesion (2.0 (1.3 to 3.0). nDS-d were more likely to develop hydrops (5.7 (3.5 to 9.5)) and necrotizing enterocolitis (1.7 (1.2 to 2.6)). In addition, nDS-d had significantly higher odds of requiring mechanical ventilation (20.7 (9.9 to 43.1)) or extracorporeal membrane oxygenation (8.7 (4.7 to 16.1)).

CONCLUSIONS

A number of characteristics, specifically certain cardiac diagnosis, place nDS at increased risk for mortality. Furthermore, development of specific medical complications or need for particular procedures increases the odds for mortality in nDS. Caregivers should be cognizant that they are taking care of a high-risk population nDS with an increased risk for mortality if these variables are present.

Right ventricular performance using myocardial deformation imaging in infants with bronchopulmonary dysplasia

OBJECTIVE

Right ventricular (RV) performance among infants with bronchopulmonary dysplasia (BPD) remains poorly understood. We tested the hypothesis that myocardial deformation imaging (MDI) strain and strain rate would allow for differentiation between infants with severe and milder forms of BPD, independent of tissue Doppler imaging (TDI) and superior to conventional echocardiographic measurements.

STUDY DESIGN

Infants with various severities of BPD (11 with none or mild, 13 with moderate and 10 with severe) underwent conventional echocardiography, TDI and MDI assessments at >36 weeks of corrected gestational age. BPD severity grading was determined according to the National Institutes of Child Health and Disease workshop rating scale by physicians blinded to the echocardiogram results. Group data were compared with one-way analysis of variance or Kruskal-Wallis tests, with post hoc multiple comparisons.

RESULTS

No differences in traditional echocardiographic parameters or TDI among the three BPD severity groups were observed; none of the infants had evidence of pulmonary hypertension. Using MDI, infants with severe BPD had lower peak global systolic strain than did infants with moderate BPD (P<0.01) or mild/none BPD (P<0.01). Early and late diastolic strain rate measurements were similar across the three groups.

CONCLUSIONS

Among infants with severe forms of BPD, evidence of abnormal RV systolic function was detected with MDI, but not traditional echocardiographic or TDI measurements. Infants with severe forms of BPD may represent a particularly high-risk subgroup for decreased RV performance warranting cardiac surveillance. MDI should be considered as a method to quantitate RV function in this population.

Correlations Between Echocardiographic Systolic and Diastolic Function with Cardiac Catheterization in Biventricular Congenital Heart Patients

Newer echocardiographic techniques may allow for more accurate assessment of left ventricular (LV) function. Adult studies have correlated these echocardiographic measurements with invasive data, but minimal data exist in the pediatric congenital heart population. Purpose of this study was to evaluate which echocardiographic measurements correlated best with LV systolic and diastolic catheterization parameters. Patients with two-ventricle physiology who underwent simultaneous echocardiogram and cardiac catheterization were included. Images were obtained in the four-chamber view. LV systolic echocardiographic data included ejection fraction, displacement, tissue Doppler imaging (TDI) s' wave, global longitudinal strain, and strain rate (SR) s' wave. Diastolic echocardiographic data included mitral E and A waves, TDI e' and a' waves, and SRe' and SRa' waves. E/TDI e', TDI e'/TDI a', E/SRe', and SRe'/SRa' ratios were also calculated. Catheterization dP/dt was used as a marker for systolic function, and LV end-diastolic pressure (EDP) was used as a marker for diastolic function. Correlations of the echocardiographic and catheterization values were performed using Pearson correlation. Twenty-nine patients were included (14 females, 15 males). Median age at catheterization was 3.4 years (0.04-17.4 years). dP/dt was 1258 ± 353 mmHg/s, and LVEDP was 10.8 ± 2.4 mmHg. There were no significant correlations between catheterization dP/dt and systolic echocardiographic parameters. LVEDP correlated significantly with SRe' (r = -0.4, p = 0.03), SRa' (r = -0.4, p = 0.03), and E/SRe' (r = 0.5, p = 0.004). In pediatric congenital heart patients, catheterization dP/dt did not correlate with echocardiographic measurements of LV systolic function. Further studies are needed to determine which echocardiographic parameter best describes LV systolic function in this population. Strain rate analysis significantly correlated with LVEDP. Strain rate analysis should be considered as an alternative method to estimate LVEDP in this patient population.

Increased incidence of idiopathic persistent pulmonary hypertension in Down syndrome neonates

Down syndrome (DS) patients have an increased risk of developing pulmonary hypertension later in life compared to age-matched controls. The goal of this study was to determine if the incidence of persistent pulmonary hypertension of the newborn (PPHN) is also higher in neonatal DS patients compared to the general population. A retrospective chart review of DS patients admitted during a 3-year period to the neonatal intensive care unit was performed. DS patients with meconium aspiration syndrome, pulmonary infections, or pulmonary space-occupying lesions were excluded. DS patients were divided into four groups based on treatment and consisted of no intervention (A), supplemental oxygen (B,) mechanical ventilation use (C), and inhaled nitric oxide administration (D). Group D was defined as having PPHN. z test of the difference between sample and known population, chi-square, t-test, and analysis of variance with Tukey adjusted post hoc test were used for analysis. p<0.05 was considered significant. A total of 58 patients met inclusion criteria. Twenty-four DS patients were in group A, 17 in group B, 10 in group C, and 7 in group D. There was no difference between the four groups for gender (males: 10, 5, 5, and 5, respectively), gestational age (36.4, 38.2, 36.4, and 36.4 weeks, respectively), weight (2.8, 3.0, 2.4, and 3.0 kg, respectively), or the presence of congenital heart defects (17, 10, 6, and 1, respectively). The estimated number of DS patients born in the state of Ohio during this period was 598; therefore, the incidence of PPHN in DS was 1.2%. The reported incidence of PPHN is 0.1%. The reported incidence of PPHN was significantly lower versus the incidence of PPHN in DS (z=2.7, p=0.007). It was concluded that DS patients have an increased incidence of PPHN compared to historical controls regardless of baseline demographics.