uConsent: Addressing the gap in measuring understanding of informed consent in clinical research

The purpose of this study was to establish the technical merit, feasibility, and generalizability of a new measure of understanding of informed consent for use with clinical research participants. A total of 109 teens/young adults at a large, pediatric medical center completed the consenting process of a hypothetical biobanking study. Data were analyzed using a combination of classical and modern theory analytic methods to produce a final set of 19 items referred to as the uConsent scale. A requirement of the scale was that each item mapped directly onto one or more of the Basic Elements of Informed Consent from the 2018 Final Rule. Descriptive statistics were computed for each item as well as the scale as a whole. Partial credit (Rasch) logistic modeling was then used to generate difficulty/endorsability estimates for each item. The final, 19-item uConsent scale was derived using inferential methods to yield a set of items that ranged across difficulty levels (-3.02 to 3.10 logits) with a range of point-measure correlations (0.12 to 0.50), within-range item- and model-fit statistics, varying item types mapped to both Bloom's Taxonomy of Learning and required regulatory components of the 2018 Final Rule. Median coverage rate for the uConsent scale was 95% for the 25 randomly selected studies from ClinicalTrials.gov. The uConsent scale may be used as an effective measure of informed consent when measuring and documenting participant understanding in clinical research studies today.

Childhood exposures to environmental chemicals and neurodevelopmental outcomes in congenital heart disease

BACKGROUND

Children with congenital heart defects have an increased risk of neurodevelopmental disability. The impact of environmental chemical exposures during daily life on neurodevelopmental outcomes in toddlers with congenital heart defects is unknown.

METHODS

This prospective study investigated the impacts of early childhood exposure to mixtures of environmental chemicals on neurodevelopmental outcomes after cardiac surgery. Outcomes were assessed at 18 months of age using The Bayley Scales of Infant and Toddler Development-III. Urinary concentrations of exposure biomarkers of pesticides, phenols, parabens, and phthalates, and blood levels of lead, mercury, and nicotine were measured at the same time point. Bayesian profile regression and weighted quantile sum regression were utilized to assess associations between mixtures of biomarkers and neurodevelopmental scores.

RESULTS

One-hundred and forty infants were enrolled, and 110 (79%) returned at 18 months of age. Six biomarker exposure clusters were identified from the Bayesian profile regression analysis; and the pattern was driven by 15 of the 30 biomarkers, most notably 13 phthalate biomarkers. Children in the highest exposure cluster had significantly lower adjusted language scores by -9.41 points (95%CI: -17.2, -1.7) and adjusted motor scores by -4.9 points (-9.5, -0.4) compared to the lowest exposure. Weighted quantile sum regression modeling for the overall exposure-response relationship showed a significantly lower adjusted motor score (β = -2.8 points [2.5th and 97.5th percentile: -6.0, -0.6]). The weighted quantile sum regression index weights for several phthalates, one paraben, and one phenol suggest their relevance for poorer neurodevelopmental outcomes.

CONCLUSIONS

Like other children, infants with congenital heart defects are exposed to complex mixtures of environmental chemicals in daily life. Higher exposure biomarker concentrations were associated with significantly worse performance for language and motor skills in this population.

Damaging Variants in Proangiogenic Genes Impair Growth in Fetuses with Cardiac Defects

OBJECTIVE

To determine the impact of damaging genetic variation in proangiogenic pathways on placental function, complications of pregnancy, fetal growth, and clinical outcomes in pregnancies with fetal congenital heart defect.

STUDY DESIGN

Families delivering a baby with a congenital heart defect requiring surgical repair in infancy were recruited. The placenta and neonate were weighed and measured. Hemodynamic variables were recorded from a third trimester (36.4 ± 1.7 weeks) fetal echocardiogram. Exome sequencing was performed on the probands (N = 133) and consented parents (114 parent-child trios, and 15 parent-child duos) and the GeneVetter analysis tool used to identify damaging coding sequence variants in 163 genes associated with the positive regulation of angiogenesis (PRA) (GO:0045766).

RESULTS

In total, 117 damaging variants were identified in PRA genes in 133 congenital heart defect probands with 73 subjects having at least 1 variant. Presence of a damaging PRA variant was associated with increased umbilical artery pulsatility index (mean 1.11 with variant vs 1.00 without; P = .01). The presence of a damaging PRA variant was also associated with lower neonatal length and head circumference for age z score at birth (mean -0.44 and -0.47 with variant vs 0.23 and -0.05 without; P = .01 and .04, respectively). During median 3.1 years (IQR 2.0-4.1 years) of follow-up, deaths occurred in 2 of 60 (3.3%) subjects with no PRA variant and in 9 of 73 (12.3%) subjects with 1 or more PRA variants (P = .06).

CONCLUSIONS

Damaging variants in proangiogenic genes may impact placental function and are associated with impaired fetal growth in pregnancies involving a fetus with congenital heart defect.

Effect of parental origin of damaging variants in pro-angiogenic genes on fetal growth in patients with congenital heart defects: Data and analyses

The placenta is a highly vascular structure composed of both maternal and fetal elements. We have determined that damaging variants in genes responsible for the positive regulation of angiogenesis (PRA) (GO:0045766) that are inherited by the fetus impair fetal growth and placental function in pregnancies involving critical congenital cardiac defects (Russell et al., 2019). In this dataset, we present the specific genetic variants identified, describe the parental origin of each variant where possible and present the analyses regarding the potential effects of parental origin of the variant on placental function and fetal growth. The data presented are related to the research article "Damaging variants in pro-angiogenic genes impair growth in fetuses with cardiac defects" (Russell et al., 2019).

Remote Ischemic Preconditioning Does Not Prevent White Matter Injury in Neonates

BACKGROUND

Remote ischemic preconditioning (RIPC) is a mechanism to protect tissues from injury during ischemia and reperfusion. We investigated the neuroprotective effects of RIPC in neonates undergoing cardiac surgery.

METHODS

The outcome was white matter injury (WMI), assessed by the change in volume of WMI from preoperative to postoperative brain magnetic resonance imaging (MRI). Patients were randomized to RIPC or SHAM. RIPC was induced prior to cardiopulmonary bypass by four 5-minute cycles of blood pressure cuff inflation to produce ischemia of the lower extremity. For patients randomized to SHAM, the cuff was positioned, but not inflated.

RESULTS

The study included 67 patients, with 33 randomized to RIPC and 34 randomized to SHAM. Preoperative and postoperative MRIs were available in 50 patients, including 26 of the 33 RIPC patients and 24 of the 34 SHAM patients. There were no differences in baseline and operative characteristics for either the overall study group or the group with evaluable MRIs. WMI was identified in 28% of the patients preoperatively and in 62% postoperatively. There was no difference in the prevalence of WMI by treatment group (p > 0.5). RIPC patients had an average change in WMI of 600 mL³, and SHAM subjects had an average WMI change of 107 mL³. There was no significant difference in the mean value of WMI change between patients who received RIPC and those who received SHAM treatments (p = 0.178).

CONCLUSIONS

In this randomized, blinded clinical trial, there was no evidence that use of RIPC provides neuroprotection in neonates undergoing repair of congenital heart defects with cardiopulmonary bypass.

Hearing Loss after Cardiac Surgery in Infancy: An Unintended Consequence of Life-Saving Care

OBJECTIVES

To investigate the prevalence of hearing loss after cardiac surgery in infancy, patient and operative factors associated with hearing loss, and the relationship of hearing loss to neurodevelopmental outcomes.

STUDY DESIGN

Audiologic and neurodevelopmental evaluations were conducted on 348 children who underwent repair of congenital heart disease at the Children's Hospital of Philadelphia as part of a prospective study evaluating neurodevelopmental outcomes at 4 years of age. A prevalence estimate was calculated based on presence and type of hearing loss. Potential risk factors and the impact of hearing loss on neurodevelopmental outcomes were evaluated.

RESULTS

The prevalence of hearing loss was 21.6% (95% CI, 17.2-25.9). The prevalence of conductive hearing loss, sensorineural hearing loss, and indeterminate hearing loss were 12.4% (95% CI, 8.8-16.0), 6.9% (95% CI, 4.1-9.7), and 2.3% (95% CI, 0.6-4.0), respectively. Only 18 of 348 subjects (5.2%) had screened positive for hearing loss before this study and 10 used a hearing aid. After adjusting for patient and operative covariates, younger gestational age, longer postoperative duration of stay, and a confirmed genetic anomaly were associated with hearing loss (all P < .01). The presence of hearing loss was associated with worse language, cognition and attention (P <.01).

CONCLUSIONS

These findings suggest that the prevalence of hearing loss in preschool children after heart surgery in infancy may be 20-fold higher than in the 1% prevalence seen in the general population. Younger gestational age, presence of a genetic anomaly, and longer postoperative duration of stay were associated with hearing loss. Hearing loss was associated with worse neurodevelopmental outcomes.

Enteral feeding and caloric intake in neonates after cardiac surgery

BACKGROUND

Adequate enteral nutrition may be difficult to achieve early in neonates after cardiac surgery, but it is essential for growth, wound healing, and immune function.

OBJECTIVE

To assess caloric intake in neonates receiving enteral nutrition after surgery.

METHODS

A retrospective chart review was conducted of daily enteral caloric intake in the cardiac intensive care unit of a tertiary children's hospital. Data on the institution of enteral feeding and the discontinuation of parenteral nutrition were assessed for full-term neonates who had undergone cardiac surgery.

RESULTS

Caloric intake was assessed in 100 patients, 52 with biventricular cardiac defects and 48 with a functional single ventricle. The median duration of stay in the cardiac intensive care unit was 13 days (range, 4-69), and patients received enteral feeding exclusively for a median of 5 days (range, 1-43). In total, 705 patient days were evaluated. The median caloric intake per day was 93 kcal/kg (range, 43-142). A goal of 100 kcal/kg was achieved for 48.4% of patient days and 120 kcal/kg for only 19.7% of patient days. Median weight change for the period of enteral feeding was -20 g (range, -775 to 1485 g).

CONCLUSIONS

Enteral feeding alone is often suboptimal after neonatal cardiac surgery. New strategies to improve caloric intake may enhance postoperative recovery.

Long-term noninvasive arrhythmia assessment after total anomalous pulmonary venous connection repair

BACKGROUND

Pediatric patients with a history of atrial surgery are at risk for the development of sinus node dysfunction and atrial arrhythmias. However, there has been no comprehensive, long-term, electrophysiologic study of patients who have undergone repair of total anomalous pulmonary venous connection.

METHODS

We evaluated school-aged and adolescent survivors of isolated total anomalous pulmonary venous connection repair from January 1983 to December 1996 to assess for sinus node dysfunction, atrioventricular block, and atrial and ventricular arrhythmias. Assessment was limited to an electrocardiogram, 24-hour Holter monitor, and exercise stress test.

RESULTS

Twenty-nine children were evaluated 11.2 +/- 3.6 years after their initial operative repair. The mean age at repair was 36.0 +/- 43.0 days. Electrophysiologic studies revealed evidence of sinus node dysfunction, including sinus bradycardia, sinus pauses, and chronotropic impairment, in most of the patients. Twenty-nine percent of patients showed chronotropic impairment on exercise testing. Atrioventricular conduction abnormalities occurred in 2 patients. Single atrial and ventricular premature complexes were frequent, but complex tachyarrhythmias were less common. There was 1 patient who had nonsustained supraventricular tachycardia and 2 patients who had nonsustained ventricular tachycardia. No statistically significant relationships were found between hypothesized variables and arrhythmia outcomes.

CONCLUSIONS

Survivors of total anomalous pulmonary venous connection repair appear to have a high incidence of signs of sinus node dysfunction and a low incidence of atrioventricular block in follow-up. Significant atrial and ventricular arrhythmias appear to be uncommon. Despite a favorable overall long-term outcome, these patients warrant ongoing clinical follow-up for arrhythmia surveillance.

The relationship of postoperative electrographic seizures to neurodevelopmental outcome at 1 year of age after neonatal and infant cardiac surgery

OBJECTIVE

The occurrence of a seizure after the arterial switch operation is associated with a worse long-term neurodevelopmental outcome. The significance of seizures after neonatal and infant repair of other congenital heart defects is not known.

METHODS

A recent study at our institution demonstrated seizures documented by 48-hour electroencephalographic monitoring in 20 (11%) of 178 neonates and infants after surgery for complex congenital heart defects, including hypoplastic left heart syndrome or variants. The developmental outcomes of this cohort were evaluated at 1 year of age by using the Bayley Scales of Infant Development II, which yields 2 scores: the Mental Developmental Index and the Psychomotor Developmental Index.

RESULTS

Developmental evaluations were performed in 114 (70%) of 164 survivors, including 36 with hypoplastic left heart syndrome. Postoperative electroencephalographic seizures had occurred in 15 (13%) of 114 of the entire group and in 8 (22%) of 36 of those with hypoplastic left heart syndrome. For the entire cohort, the Mental Developmental Index was 92.3 +/- 13.5, and the Psychomotor Developmental Index was 79.9 +/- 18.8 for patients without seizures, compared with 90.3 +/- 10.7 and 74.4 +/- 19.3 for those with seizures (both P > .5). For the hypoplastic left heart syndrome subgroup, the Mental Developmental Index was 92.3 +/- 14.9, and the Psychomotor Developmental Index was 74.8 +/- 19.3 for patients with seizures, compared with 91.9 +/- 12.4 and 73.9 +/- 18.3 for those without seizures (both P > .5). A frontal onset of seizures was predictive of a lower score on the Psychomotor Developmental Index, but not on the Mental Developmental Index.

CONCLUSIONS

The occurrence of a seizure after cardiac operation is a marker of central nervous system injury. However, in this cohort of neonates and infants with complex congenital heart defects, the occurrence of a seizure was not predictive of a worse developmental outcome at 1 year of age as assessed by the Bayley Scales of Infant Development II.

Increasing duration of deep hypothermic circulatory arrest is associated with an increased incidence of postoperative electroencephalographic seizures

OBJECTIVE

Electroencephalographic seizures have been shown to occur in 5% to 20% of neonates and infants after biventricular repair of a variety of cardiac defects. Occurrence of a seizure is a predictor of adverse long-term neurodevelopmental sequelae. The contemporary incidence of postoperative seizures after repair of cardiac defects such as hypoplastic left heart syndrome and other forms of single ventricle is not known.

METHODS

A prospective study of 178 patients less than 6 months of age undergoing cardiopulmonary bypass with or without deep hypothermic circulatory arrest (DHCA) was conducted at a single institution from September 2001 through March 2003 to identify postoperative seizures assessed by 48-hour continuous video electroencephalographic monitoring.

RESULTS

Cardiac defects included transposition of the great arteries with or without a ventricular septal defect (n = 12), ventricular septal defect with or without coarctation (n = 28), tetralogy of Fallot (n = 24), hypoplastic left heart syndrome or variant (n = 60), other functional single ventricle (n = 14), and other defects suitable for biventricular repair (n = 40). Median age at the time of the operation was 7 days (range, 1-188 days) and was 30 days or less in 110 (62%) patients. DHCA was used in 117 (66%) patients, with multiple episodes in 9 patients. Median total duration of DHCA was 40 minutes (range, 1-90 minutes). Electroencephalographic seizures were identified in 20 (11.2%) patients. Seizures occurred in 15 (14%) of 110 neonates and 5 (7%) of 68 older infants. Seizures occurred in 1 (4%) of 24 patients with tetralogy of Fallot, 1 (8%) of 12 with transposition of the great arteries, and 11 (18%) of 60 with hypoplastic left heart syndrome or variant. By stepwise logistic regression analysis, once increasing duration of total DHCA (P = .001) was considered, no other variable improved prediction of occurrence of a seizure. Patients with DHCA duration of more than 40 minutes had an increased incidence of seizures (14/58 [24.1%]) compared with those with a DHCA duration of 40 minutes or less (4/59 [6.8%], P = .04). The incidence of seizures for patients with a DHCA duration of 40 minutes or less was not significantly different from those in whom DHCA was not used (2/61 [3.3%], P = .38).

CONCLUSIONS

In the current era, continuous electroencephalographic monitoring demonstrates early postoperative seizures in 11.2% of a heterogeneous cohort of neonates and infants with complex congenital heart defects. Increasing duration of DHCA was identified as a predictor of seizures. However, the incidence of seizures in children with limited duration of DHCA was similar to that in infants undergoing continuous cardiopulmonary bypass alone.