Understanding paediatric COVID-19 vaccination during the pandemic: a prospective cohort and a population-based registry study.

Background: Despite the early demonstrated safety and effectiveness of COVID-19 vaccines in children, uptake was slow throughout the pandemic and remains low globally. Understanding vaccine refusal could provide insights to improving vaccine uptake in future pandemics. Methods: In a population-wide registry of all COVID-19 paediatric vaccination appointments, we used interrupted time series analysis to evaluate the impact of public policies. In a population-based cohort of adults, we used population attributable fractions to assess the individual and joint contributions of potential determinants to paediatric COVID-19 vaccination, and used mediation analysis to identify modifiable mediators between political views and paediatric vaccination. Findings: School vaccination requirements were associated with an increase in vaccination appointments by 278.7% (95% CI 85.3-673.9) in adolescents aged 12-17 and 112.8% (27.6-255.0) in children aged 5-11. Government-mandated vaccine pass, required for entry into restaurants, shopping malls and supermarkets, was associated with increased vaccination appointments by 108.7% (26.6-244.0) in adolescents. The following four determinants may explain 82.5% (63.5-100.0) of the reasons why children were unvaccinated: familial political views, vaccine hesitancy for children, mistrust in doctors and academics, and vaccine misconceptions. The influence of political views may be mitigated since 95.9% (76.4-100.0) of its association with vaccine reluctance for adolescents was mediated by modifiable factors such as mistrust in health authorities and low vaccine confidence. Interpretation: School vaccination requirements and vaccine passes were associated with increased vaccine uptake. Clinicians should recognise that factors beyond health, such as political views, can influence paediatric vaccine uptake to a significant extent. Nonetheless, such influences could be mitigated by targeted interventions and public policies. Funding: Hong Kong Jockey Club Charities Trust, Research Grants Council, University Grants Committee, and Health Bureau.

Deficits in neural encoding of speech in preterm infants.

Preterm children show developmental cognitive and language deficits that can be subtle and sometimes undetectable until later in life. Studies of brain development in children who are born preterm have largely focused on vascular and gross anatomical characteristics rather than pathophysiological processes that may contribute to these developmental deficits. Neural encoding of speech as reflected in EEG recordings is predictive of future language development and could provide insights into those pathophysiological processes. We recorded EEG from 45 preterm (≤ 34 weeks of gestation) and 45 term (≥ 38 weeks) Chinese-learning infants 0-12 months of (corrected) age during natural sleep. Each child listened to three speech stimuli that differed in lexically meaningful pitch (2 native and 1 non-native speech categories). EEG measures associated with synchronization and gross power of the frequency following response (FFR) were examined. ANCOVAs revealed no main effect of stimulus nativeness but main effects of age, consistent with earlier studies. A main effect of prematurity also emerged, with synchronization measures showing stronger group differences than power. By detailing differences in FFR measures related to synchronization and power, this study brings us closer to identifying the pathophysiological pathway to often subtle language problems experienced by preterm children.

Improving Consistency and Accuracy of Neonatal Amplitude-Integrated Electroencephalography.

OBJECTIVE: This study aimed to improve the utilization of amplitude-integrated electroencephalography (aEEG) in a neonatal unit by improving aEEG documentation, aEEG knowledge, and pattern recognition ability of neonatal staff. METHODS: A quality improvement (QI) program comprising the two Plan-Do-Study-Act (PDSA) cycles was conducted in a level-3 neonatal intensive care unit. The first cycle was focused on improving aEEG documentation with the primary outcome indicator being compliance with aEEG documentation. The second cycle was focused on aEEG interpretation in a health care professional education program with the outcome indicators being accuracy of seizure identification on aEEG and change in conventional EEGs (cEEG) performed. Other outcome indicators included accuracy in identification of background pattern, sleep-wake cycles and artifacts. Process indicators included improvement in aEEG-related knowledge. RESULTS: First PDSA cycle includes lectures on aEEG interpretation, a bedside key, and documentation form. Second PDSA cycle includes online aEEG education pack and detailed aEEG guideline. There was a significant improvement in aEEG documentation after the implementation of both PDSA cycles. Seven of the 46 patients (15.2%) had isolated electrographic seizures which would not have been identified in the pre-aEEG monitoring era. There was an increase in the number of patients with cEEGs done but a steady decrease in number of cEEGs per patient. CONCLUSION: With the successful application of standardized QI methods, improvements in outcome indicators, such as correct aEEG pattern recognition and improved coverage of at risk infants with cEEGs, were observed. Our QI measures were associated with improvement in aEEG pattern recognition. KEY POINTS: · Consistent and accurate use of aEEG is challenging.. · Standardized forms and guidelines improve aEEG interpretation consistency and documentation.. · Interactive self-paced online education packs can improve aEEG knowledge and pattern recognition..

Sleep Duration and Adiposity in Children and Adults: Observational and Mendelian Randomization Studies.

OBJECTIVE: This study used two complementary designs, an observational and a Mendelian randomization (MR) study, to assess whether sleep duration causes adiposity in children and adults. METHODS: In Hong Kong's "Children of 1997" birth cohort, the adjusted cross-sectional associations of sleep duration with BMI z score and obesity and overweight were assessed at ~11 years of age. Generalized estimating equations were also used to examine longitudinal associations of sleep duration at ~11 years with annual BMI z score and obesity and overweight at about 11 to 16 years of age. Using MR, this study assessed the association of genetically predicted sleep duration, based on 54 single-nucleotide polymorphisms, applied to genetic studies of adiposity in children (n = 35,668), men (n = 152,893), and women (n = 171,977). RESULTS: Longer sleep was cross-sectionally associated with lower BMI z score at ~11 years of age (-0.13 per category, 95% CI: -0.22 to -0.04) and at about 11 to 16 years of age longitudinally in girls (-0.39, 95% CI: -0.66 to -0.13). Using MR, sleep duration was inversely associated with BMI in children (-0.29 SD per hour, 95% CI: -0.54 to -0.04), but was not clearly associated with BMI in adults, particularly for women. CONCLUSIONS: A small beneficial effect of sleep on BMI in children cannot be ruled out.

Life-Threatening Hemolytic Anemia after Intrapleural Instillation of OK-432 for Treatment of Congenital Chylothorax.

Recent reports have advocated treatment of congenital chylothorax with chemical pleurodesis via intrapleural administration of OK-432. Severe complications have not been reported, but recently we have encountered a life-threatening case of massive hemolysis after the procedure. The hemoglobin of the infant decreased from 8.7 to 3.1 g/dl within 48 h, with concomitant severe hyperbilirubinemia (472 µmol/l) requiring exchange transfusion. Frontline neonatologists should be aware of this rare but potentially life-threatening adverse reaction. In addition, it is possible that a longer indwelling time (3.5 vs. 0.5 h) for OK-432 pleurodesis may alter the therapeutic response.

Gestational Age, Birthweight for Gestational Age, and Childhood Hospitalisations for Asthma and Other Wheezing Disorders.

BACKGROUND: Preterm birth, early term birth, and low birthweight are associated with childhood wheezing disorders in developed Western settings, but observed associations could be confounded by socio-economic position. This study aims to clarify such associations in a developed non-Western setting with a different confounding structure. METHODS: Using Cox regression, we examined the adjusted associations of gestational age and birthweight for gestational age with time to first public hospital admission for asthma, bronchitis, and bronchiolitis (International Classification of Diseases, Ninth Version Clinical Modification 466, 490, and 493) from 9 days to 12 years in a population-representative birth cohort of 8327 Chinese children in Hong Kong, a developed setting with less clear social patterning of prematurity or birthweight. Analyses were adjusted for infant and parental characteristics and socio-economic position. RESULTS: Children born late preterm (34 to <37 weeks) had higher risk of hospitalisation for asthma and other wheezing disorders [hazard ratio (HR) 1.99, 95% confidence interval (CI) 1.48, 2.67] than children born full term (39 to <41 weeks). Early term births (37 to <39 weeks) had HR 1.01 (95% CI 0.84, 1.22), late term births (41 to <42 weeks) had HR 0.77 (95% 0.59, 1.01), and post-term births (≥42 weeks) had HR 0.56 (95% CI 0.32, 0.98). Large for gestational age was associated with lower risk of hospitalisation (HR 0.76, 95% CI 0.57, 0.99). CONCLUSION: The association of preterm birth with childhood wheezing could be biologically mediated. We cannot rule out an association for early term births.

End-of-life decision-making for newborns: a 12-year experience in Hong Kong.

SETTING: Neonatal end-of-life decisions could be influenced by cultural and ethnic backgrounds. These practices have been well described in the West but have not been systematically studied in an Asian population. OBJECTIVES: To determine: (1) different modes of neonatal death and changes over the past 12 years and (2) factors influencing end-of-life decision-making in Hong Kong. DESIGN: A retrospective study was conducted to review all death cases from 2002 to 2013 in the busiest neonatal unit in Hong Kong. Modes of death, demographical data, diagnoses, counselling and circumstances around the time of death, were collected and compared between groups. RESULTS: Of the 166 deaths, 46% occurred despite active resuscitation (group 1); 35% resulted from treatment withdrawal (group 2) and 19% occurred from withholding treatment (group 3). A rising trend towards treatment withdrawal was observed, from 20% to 47% over the 12-year period. Similar number of parents chose extubation (n=44, 27%) compared with other modalities of treatment limitation (n=45, 27%). Significantly more parents chose to withdraw rather than to withhold treatment if clinical conditions were 'stable' (p=0.03), whereas more parents chose withholding therapy if treatment was considered futile (p=0.03). CONCLUSION: In Hong Kong, a larger proportion of neonatal deaths occurred despite active resuscitation compared with Western data. Treatment withdrawal is, however, becoming increasingly more common. Unlike Western practice, similar percentages of parents chose other modalities of treatment limitation compared with direct extubation. Cultural variance could be a reason for the different end-of-life practice adopted in Hong Kong.

The neonatal resuscitation algorithm organized cart is more efficient than the airway-breathing-circulation organized drawer: a crossover randomized control trial.

INTRODUCTION: Although there is consensus on the resuscitation of newborns, there is no standardization on how resuscitation equipment should be organized. This might lead to difficulty and inefficiency in retrieval of the right equipment during resuscitation. The neonatal resuscitation carts organized in accordance with the American Academy of Pediatrics (AAP) Neonatal Resuscitation Program (NRP) algorithm might result in more efficient retrieval of resuscitation equipment. OBJECTIVES: To compare user preference and lengths of time required to retrieve standard resuscitation equipment from an NRP Cart versus a generic storage drawer. STUDY DESIGN: A prospective, randomized, controlled, and crossover trial was conducted during simulation-based NRP provider courses in the Accident & Emergency Training Centre from September to October 2013. The mean time of accurate equipment retrieval and ease of use, which was rated by the participants using a five-point Likert scale (1=most difficult, 5=easiest to use), were compared using the Wilcoxon signed-rank test because of right skew. RESULTS: A total of 55 individuals participated in this study. The mean length of time required for equipment retrieval from the NRP Cart was significantly less than that from the drawer (Z=-3.90, P<0.01, median=36.23 s, interquartile range=97 s). In general, the NRP Cart was 32% faster than the drawer when extensive resuscitation equipment was required. All the participants rated the NRP Cart as easier to use than the drawer, with a median score of 4 for NRP Cart and 3 for the drawer (Z=-4.10, P<0.01, interquartile range=2). CONCLUSION: The NRP Cart was superior to the generic drawer in terms of the speed of equipment retrieval and user acceptability.

Late prematurity and adiposity in adolescents: Evidence from "Children of 1997" birth cohort.

OBJECTIVE: The association of late prematurity with later adiposity is unclear, and the mediating role of infant growth is seldom studied. We assessed the association of late prematurity with markers of adiposity in adolescence and tested whether accelerated infant weight gain mediated the association. METHODS: In the Chinese birth cohort "Children of 1997," we used multivariable linear regression to assess the adjusted association of late premature (n = 295), compared to term (n = 6874), births with markers of adiposity at 14 years. We tested whether any association was mediated by accelerated weight gain from birth to 12 months, i.e., a change in weight z-score ≥0.67. RESULTS: Late premature births had greater body mass index (BMI) z-score (0.21, 95% confidence interval (CI) 0.07, 0.35), waist-hip ratio z-score (0.16, 95% CI 0.03, 0.29), and waist-height ratio z-score (0.27, 95% CI 0.14, 0.40) than term births in adolescence. The association of late prematurity with higher adolescent BMI, but not waist ratios, was mediated by accelerated infant weight gain. CONCLUSIONS: Late prematurity was associated with higher BMI and waist ratios in adolescence, but only the association with BMI was mediated by infant weight gain, suggesting vulnerability to metabolic risk in late premature births may arise through multiple pathways.