Background: Pulmonary arterial hypertension (PAH) is a serious disease with poor prognosis, especially in infants or preterm babies and there is still no optimal treatment for this disease. Noradrenalin (NE) is a vasoactive mediator which is released by sympathetic ganglion. According to previous studies, NE/α1-adrenoreceptors is not only in regulating normal physiologic responses, but also in the pathogenesis of PAH. However, the mechanisms of NE in PAH are not fully understood. Methods: Human PASMC (PASMC) was used in this study. Cell viability assay and Wound healing assay were used to evaluate the proliferation and migration of PASMC. Immunoprecipitation and western blots analysis were used to investigate the mechanisms which involved in NE-induced PASMC proliferation. Results: We investigated that NE could induce human PASMC proliferation and migration. Furthermore, we first find that endothelin 1 (ET-1) signaling pathway plays an important role in NE-induced PASMC proliferation. ET1 is a critical molecular which is known for regulating cell growth and migration. We investigated that NE could increase NE-1 secretion, further enhancing ET-1 bind to its receptors. For further clarifying the downstream signals in NE/ET-1 induced PASMC proliferation, we detected the phosphorylation and expression levels of ERK and JNK. Conclusions: By combining the results from ours and previous studies, we believed that JNK/c-jun pathway may play an important role in NE-induced PASMC proliferation. Key Words: Noradrenaline; Pulmonary Arterial Hypertension; Pulmonary Artery Smooth Muscle Cells; Endothelin-1; JNK/c-Jun Signaling.

Background/purpose: The use of high-flow nasal cannulas (HFNC) in patients admitted to the pediatric intensive care unit (PICU) has gradually increased worldwide; however, details on clinical efficacy remain limited in Taiwan. Therefore, we explored the clinical characteristics and outcomes of pediatric patients using HFNC in the PICU.MethodsMedical records were retrospectively collected from pediatric patients (aged <18 years) who received HFNC support from December 2021 to January 2023 in the PICU of a medical center. Outcome parameters included treatment failure (defined as increased respiratory support to advanced non-invasive ventilators or intubations), duration of support from HFNC, and changes in clinical parameters after initiating HFNC.ResultsA total of 261 episodes of HFNC use were included, with a failure rate of 24.5% and a median support length of 4 days. Multivariable analysis showed that infant age (adjusted odds ratio [aOR]: 2.1, p = 0.02) and accompanying complex chronic disease (aOR: 4.4, p = 0.014) were risk factors for treatment failure and a diagnosis of asthma or bronchiolitis had a lower hazard of treatment failure (aOR: 0.29, p = 0.025) than other diagnoses did. Improvements in clinical parameters, including pulse rate, respiratory rate, SpO2, and CO2 levels, were observed 24 h after the initiation of HFNC.ConclusionThe application of HFNC in the PICU in Taiwan is effective but should be performed with care in infants with accompanying complex chronic diseases. In addition to low treatment failure, HFNC utilizations stabilized the clinical parameters of children with asthma/bronchiolitis within one day.

BACKGROUND:Children with coronavirus disease 2019 (COVID-19) present with mild but persistent pulmonary disease. Limited studies have explored post-infection aerobic capacity and quantification of symptoms. This study aimed to quantify post-COVID-19 fatigue, dyspnea, and pulmonary functional capacity while exploring associated factors. METHODS:This prospective cohort study enrolled 6-12-year-old children with COVID-19. Participants' parents completed questionnaires assessing post-COVID-19 fatigue (Pediatric Quality of Life Inventory Multidimensional Fatigue Scale, including general, sleep, and cognition, with high scores indicating less severity) and dyspnea (Modified Medical Research Council Dyspnea Scale). Six-minute walk tests (6MWT) were performed with records of distances to assess pulmonary functional capacity. RESULTS:This study enrolled 21 children with seven (33 %) exhibiting persistent symptoms post-COVID-19 infection. These children had a lower COVID-19 vaccination rate (57 % vs. 100 %, p = 0.026) and a reduced sleep-related fatigue scale (69.0 vs. 80.4, p = 0.043) than those without persistent symptoms. Nineteen children performed the 6MWT achieving a mean distance of 623 m (standard deviation, SD: 231) and a mean Z-score of 2.8 (SD: 1.4). Linear regression analysis identified older age as a risk factor for fatigue (β-coefficient -0.45, p = 0.040), and the cognitive fatigue scale correlated with the Z-score of the 6MWT distances (β-coefficient: -0.56, p = 0.013). CONCLUSION:Children with post-COVID-19 symptoms had lower vaccination rates and higher sleep-related fatigue levels. Older children experienced more severe fatigue and the performance of 6MWT correlated with cognition-related fatigue scale.

BACKGROUND:Chronic kidney disease (CKD) represents a significant global health concern. Zinc protoporphyrin (ZnPP), a byproduct formed during disrupted iron metabolism, is frequently elevated in individuals with renal dysfunction. The contribution of ZnPP to kidney pathology remains inadequately understood. Here, we investigated the role of ZnPP in CKD progression in vitro and in vivo. METHODS:A adenine-induced CKD mouse model and the renal tubular epithelial cell lines (HK-2 and NRK-52E) were used. In some experiments, CKD mice were treated with the N,N,N',N'-tetrakis (2-pyridinylmethyl)-1,2-ethanediamine (TPEN), a potent zinc chelator as a ZnPP inhibitor. The ferroptosis-related signaling molecules were determined. RESULTS:ZnPP accumulation, iron overload, ferroptotic activity, and kidney damage, including fibrosis, in CKD mouse kidneys were observed. In vitro, ZnPP exposure increased intracellular labile iron and reactive oxygen species, ultimately inducing ferroptosis in tubular cells. ZnPP disrupted iron regulation by enhancing iron uptake through the upregulation of transferrin and divalent metal transporter 1, while suppressing iron storage and export via reduced expression of ferritin heavy chain and ferroportin. The iron chelator deferoxamine significantly mitigated ZnPP-induced iron accumulation, oxidative stress, and cell death. ZnPP also markedly increased heme oxygenase (HO) activity and HO-1 protein expression in renal tubular cells. Administration of TPEN substantially reduced renal ZnPP levels and alleviated ferroptosis and kidney injury in CKD mice. CONCLUSION:These findings highlight ZnPP as a previously unrecognized driver of ferroptosis via HO-1 overactivation and dysregulated iron metabolism in CKD, and suggest that targeting ZnPP-mediated pathways may offer a novel therapeutic strategy for CKD.

BACKGROUND:The Fontan operation is widely regarded as a highly successful and effective palliative measure for many congenital heart diseases. However, among patients who undergo Fontan procedures, Fontan failure inevitably occurs in some cases, giving rise to various complications, including protein-losing enteropathy, plastic bronchitis, refractory arrhythmia, and coagulopathy. When Fontan fails, heart transplantation emerges as one of the treatment options. METHODS:This retrospective study examines the outcomes of heart transplantation in 10 patients experiencing Fontan failure over a span of 23 years at a single institution. RESULTS:The statistical analysis reveals survival rates of 80.0%, 60.0%, and 33.3% at 1, 3, and 5 years posttransplantation, respectively. Moderate or severe atrioventricular valve regurgitation (AVVR) emerges as a risk factor for posttransplantation mortality. Additionally, pretransplant atrial tachycardia is identified as a risk factor for early mortality following heart transplantation. CONCLUSIONS:Moderate or severe AVVR is a risk factor for posttransplantation mortality in patients with Fontan circulation failure, while pretransplant atrial tachycardia is a risk factor for early mortality after cardiac transplantation.

Chronic kidney disease (CKD) leads to the accumulation of uremic toxins such as indoxyl sulfate (IS), which has been linked to myopathy. Iron is essential for muscle growth and differentiation, with ferrous iron (Fe2+) contributing to intracellular oxidative stress. Although IS known to affect muscle differentiation and regeneration, the underlying mechanisms remain poorly understood. Both iron overload and deficiency can negatively impact muscle growth. We hypothesized that IS impairs myoblast differentiation by disrupting the balance between intracellular oxidative stress and iron metabolism. To test this, we exposed C2C12 myoblasts and primary human skeletal muscle myoblasts to IS during the proliferation phase and maintained IS exposure throughout the differentiation process. IS treatment reduced both intracellular reactive oxygen species (ROS) and free Fe2+ levels during differentiation. It also altered intracellular iron metabolism and upregulated the gene expression and activity of antioxidant-related enzymes, maintaining the cells in a high-antioxidant state and establishing a new oxidative balance. Unexpectedly, Fe2+ (FeSO4) supplementation, with or without IS, significantly increased ROS levels and further exacerbated the inhibition of myoblast differentiation induced by IS, suggesting that cellular redox homeostasis was disrupted. These findings reveal that IS induces an imbalance in cellular iron metabolism and oxidative stress, providing new insights into an alternative mechanism by which IS inhibits muscle differentiation and regeneration.

There is limited research about the direct effects of diesel exhaust particles (DEPs) on cardiomyocytes. The respirable DEPs asorbed many organic substances such as polycyclic aromatic hydrocarbons (PAHs). Here, we used the standard DEPs, enriched in PAHs and their derivatives, from the National Institute of Standards and Technology of the United States and extracted the organic compounds of DEPs (DEPEs) to examine the effects and mechanisms of DEPEs on rat primary neonatal cardiomyocytes (NRCMs) and rat embryonic H9c2 cardiomyocytes. No cytotoxicity was found at DEPEs concentrations up to 25 μg/mL in NRCMs. By evidence of immunofluorescence of desmin, cellular protein content, and mRNA levels of brain natriuretic peptide and β-myosin heavy chain, the cell hypertrophy was induced by DEPEs in NRCMs. DEPEs induced cytotoxicity in H9c2 cells at the concentration of 15 μg/mL and up. DEPEs exposure significantly induced apoptosis and protein expression of phosphorylated JNK and endoplasmic reticulum stress markers glucose-regulated protein 78 and C/EBP-homologous protein in H9c2 cells. Altogether, the direct effects of PAHs-enriched DEPEs include cytotoxic effects observed in H9c2 cells at higher concentrations and hypertrophic effects in NRCMs at concentrations without cytotoxicity. These results provide the better understanding of direct effects of DEPs on cardiomyocytes.

Background: Since April 2022, the SARS-CoV-2 Omicron variant has caused a notable increase in pediatric COVID-19 cases in Taiwan. During the acute phase of infection, some children required admissions to pediatric intensive care units (PICU). This study aimed to analyze their clinical presentations and outcomes while exploring associated factors. Methods: Medical records were retrospectively collected from patients with COVID-19 (aged <18 years) admitted to our PICU from April 2022-March 2023. Early stage is defined as the period without adequate vaccination and treatment guidelines for children from April-June 2022, and the remaining months are referred to as late stage. Clinical characteristics and outcomes were compared between patients in early and late stages. Results: We enrolled 78 children with COVID-19, with a median length of stay (LOS) in PICU of 3 days and a 5% mortality rate. Patients admitted during the early stage had lower vaccination rates (7% vs. 50%), higher pediatric logistic organ dysfunction scores (2 vs. 0.1), and longer LOS in the PICU (6 vs. 2 days) than those admitted during the late stage. Multivariate analysis identified admission during the early stage as a risk factor for prolonged LOS (>7 days) in the PICU (odds ratio: 3.65, p = 0.047). Conclusion: Without available vaccinations and suitable treatment guidelines, children with COVID-19 tended to have more severe illness and prolonged LOS in the PICU. These observations highlight the importance of vaccinations and familiarity of medical providers with adequate management of this newly-emerging infectious disease.

BACKGROUND:Extracorporeal membrane oxygenation (ECMO) is a rescue therapy for neonates with refractory respiratory failure. However, outcomes and associated risk factors in Taiwanese population are lacking. METHODS:This single-center retrospective cohort study recruited all neonates who received ECMO support for respiratory failure in our institute from 2009 to 2023. The primary outcome was the survival to hospital discharge. The secondary outcome was favorable neurological outcome. Demographic data, indications, management, and laboratory data were compared between survived and non-survived groups to identify factors associated with outcomes. RESULTS:Forty-eight patients were enrolled in this study and 23 (48 %) survived to hospital discharge. Among survived patients, 20 (42 %) had favorable neurological outcomes. One year survival was 40 %. Comparisons between the survived group and the non-survived found that factors associated with overall mortality included premature birth (hazard ratio, 2.77), low birth weight (hazard ratio, 2.67), bicarbonate level <20 mmol/L 24 h after ECMO initiation (hazard ratio, 3.75), and need of renal replacement therapy (hazard ratio, 4.01). Multivariate analysis identified low birth weight and requirement for renal replacement therapy as independent risk factors for mortality. CONCLUSION:The survival rate after ECMO support for neonates with respiratory failure in this cohort is 48 %. Low birth weight and the requirement for renal replacement therapy are associated with mortality.

OBJECTIVES:Airway anomalies increase risk of morbidity and mortality in postoperative pediatric patients with congenital heart disease (CHD). We aimed to identify airway anomalies and the association with intermediate outcomes in patients undergoing surgery for CHD. DESIGN:Single-center, hospital-based retrospective study in Taiwan, 2017-2020. SETTING:A tertiary referral hospital in Taiwan. PATIENTS:All pediatric patients who underwent surgery for CHD and were admitted to the PICU and had data about airway evaluation by cardiopulmonary CT scan or bronchoscopy. INTERVENTIONS:None. MEASUREMENTS AND MAIN RESULTS:Among 820 CHD patients identified as having undergone airway evaluation in the PICU, 185 (22.6%) were diagnosed with airway anomalies, including structural lesions in 146 of 185 (78.9%), and dynamic problems were seen in 87 of 185 (47.0%). In this population, the explanatory factors associated with greater odds (odds ratio [OR]) of airway anomaly were premature birth (OR, 1.90; p = 0.002), genetic syndromes (OR, 2.60; p < 0.001), and in those with preoperative ventilator use (OR, 4.28; p < 0.001). In comparison to those without airway anomalies, the presence of airway anomalies was associated with higher hospital mortality (11.4% vs. 2.7%; p < 0.001), prolonged intubation days (8 d [1-27 d] vs. 1 d [1-5 d]; p < 0.001), longer PICU length of stay (23 d [8-81 d] vs. 7 d [4-18 d]; p < 0.001), and greater hazard of intermediate mortality (adjusted hazard ratio, 2.60; p = 0.001). CONCLUSIONS:In our single-center retrospective study, 2017-2020, between one-in-five and one-in-four of our postoperative CHD patients undergoing an airway evaluation had airway anomalies. Factors associated with greater odds of airway anomaly included, those with premature birth, or genetic syndromes, and preoperative ventilator use. Overall, in patients undergoing airway evaluation, the finding of an airway anomalies was associated with longer postoperative intubation duration and greater hazard of intermediate mortality.

BACKGROUND:The incidence of pediatric hospitalizations has significantly increased since the spread of the omicron variant of COVID-19. Changes of characteristics in respiratory and neurological symptoms have been reported. We performed a retrospective, cross-sectional study to characterize the MRI change in children with an emphasis on the change of cerebral vasculatures. METHODS:We retrospectively collected clinical and MRI data of 31 pediatric patients with neurological symptoms during the acute infection and abnormalities on MRI during the outbreak of omicron variant from April 2022 to June 2022 in Taiwan. The clinical manifestations and MRI abnormalities were collected and proportion of patients with vascular abnormalities was calculated. RESULTS:Among 31 pediatric patients with post-COVID-19 neurological symptoms, MRI abnormalities were observed in 15 (48.4%), predominantly encephalitis/encephalopathy (73.3%). Notable MRI findings included focal diffusion-weighted imaging (DWI) hyperintensity in cerebral cortex and thalamus, diffuse cortical T2/DWI hyperintensity, and lesions in the medulla, pons, cerebellum, and splenium of corpus callosum. Vascular abnormalities were seen in 12 (80%) patients with MRI abnormalities, mainly affecting the middle cerebral arteries. The spectrum of neurological manifestations ranged from seizures to Alice in Wonderland syndrome, underscoring the diverse impact of COVID-19 on pediatric patients. CONCLUSION:A high proportion of vascular abnormalities was observed in pediatric patients with neurological involvements, suggesting that vascular involvement is an important mechanism of neurological manifestations in omicron variant infection.

Objectives: This study aimed to identify clinical characteristics to differentiate multisystem inflammatory syndrome in children (MIS-C) and Kawasaki disease (KD) in Taiwan, an island with a delayed cluster of MIS-C and a high incidence of KD. Additionally, we studied risk factors for developing severe complications in patients with MIS-C. Methods: We conducted a retrospective, multicenter, cohort, and observational study that linked data on patients with MIS-C between May and December 2022 and patients with KD between 2019 and 2021 from 12 medical centers. Hemodynamic compromise, defined as the need for inotropic support or fluid challenge, was recorded in patients with MIS-C. We also evaluated maximal coronary Z-scores before treatment and one month after disease onset. Results: A total of 83 patients with MIS-C and 466 patients with KD were recruited. A 1:1 age and gender-matched comparison of 68 MIS-C and KD pairs showed that MIS-C patients had a lower percentage of positive BCG red halos, lower leukocyte/platelet counts, more gastrointestinal symptoms, and a higher risk of hemodynamic compromise. In Taiwan, 38.6% of MIS-C patients experienced hemodynamic compromise, with presence of conjunctivitis and elevated levels of procalcitonin (>1.62 ng/mL) identified as independent risk factors. Conclusion: We identified two independent risk factors associated with hemodynamic compromise in MIS-C patients. The comparison between matched MIS-C and KD patients highlighted significant differences in clinical presentations, like BCG red halos, which may aid in the differential diagnosis of the two disease entities, especially in regions with a high incidence rate of KD.

Background: Multisystem inflammatory syndrome in children (MIS-C) is a novel disease associated with COVID19. The COVID-19 epidemic peaked in May 2022 in Taiwan, and we encountered our first case of MIS-C in late May 2022. We aimed to present patients' clinical manifestations and identify risk factors for shock. Methods: We included patients diagnosed with MIS-C at two medical centers from May 2022 to August 2022. We separated those patients into two groups according to whether they experienced shock. We collected demographic, clinical manifestation, and laboratory data of the patients and performed statistical analysis between the two groups. Results: We enrolled 28 patients, including 13 (46 %) with shock and 15 (54 %) without shock. The median age was 6.4 years (IQR: 1.9-7.5). In single variable analysis, patients with shock tended to be older, had more neurological symptoms, more conjunctivitis and strawberry tongue, lower lymphocyte count, lower platelet counts, and higher C-reactive protein, higher procalcitonin, higher ferritin, and higher D-dimer levels than those without shock. The area under the ROC curve that used procalcitonin to be the risk factor of shock with MIS-C was 0.815 (95 % CI 0.644 to 0.987). The cutoff value obtained by ROC analysis of procalcitonin was 1.68 ng/mL. With this cutoff, the test characteristics of procalcitonin were as follows: sensitivity 77 %, specificity 93 %, positive predictive value 91 %, negative predictive value 82 %. Multivariable analysis revealed that procalcitonin was the only independent risk factor of shock with MIS-C on admission (OR, 26.00, 95 % CI, 1.01-668.89). Conclusions: MIS-C patients with high initial procalcitonin levels have higher risks of experiencing shock and may need ICU admission.

Aims: Advanced glycation end-products (AGEs) are implicated in the age-related decline of renal function, exacerbated by conditions, such as hyperglycemia and oxidative stress. The accumulation of AGEs in the kidneys contributes to the progressive decline in renal function observed with aging. However, the precise role and mechanisms of AGEs in the age-related decline of renal function remain unclear. In this study, we investigated the impact and potential mechanisms of AGEs on aging kidneys in naturally aging mice. Materials and methods: Male C57BL/6 mice were divided into three groups: 6-, 57-, and 107-week-old. First, the 6and 107-week-old mice were euthanized. The remaining mice were divided into young (6 weeks) and old (57 weeks) groups. The 57-week-old mice were orally administered aminoguanidine (100 mg/kg/day), an AGEs inhibitor, or vehicle for 13 weeks, resulting in a final age of 70 weeks. The serum and kidney tissues were collected for biochemical measurement, histological examination, immunohistochemistry staining, and immunoblotting analysis. Key findings: Our findings revealed a notable accumulation of AGEs in both serum and kidney tissue specimens and renal dysfunction in naturally aging mice. Aminoguanidine not only reversed AGEs accumulation but also ameliorated renal dysfunction. Additionally, aminoguanidine attenuated the upregulation of fibrosis markers (phosphorylated p38/alpha-SMA and C/EBP homologous protein, CHOP), senescence markers (p53 and p21), and oxidative stress marker (4-HNE) in the aging kidneys. Significance: These findings underscore the critical role of AGEs in age-related renal dysfunction and highlight the therapeutic potential of aminoguanidine in mitigating fibrosis and senescence, offering prospective avenues for combating age-associated renal ailments.

Community‐acquired pneumonia (CAP) is a serious clinical concern. A lack of accurate diagnosis could hinder pathogen‐directed therapeutic strategies. To solve this problem, we evaluated clinical application of nested multiplex polymerase chain reaction (PCR) in children with severe CAP. We prospectively enrolled 60 children with severe CAP requiring intensive care between December 2019 and November 2021 at a tertiary medical center. Nested multiplex PCR respiratory panel (RP) and pneumonia panel (PP) were performed on upper and lower respiratory tract specimens. We integrated standard‐of‐care tests and quantitative PCR for validation. The combination of RP, PP, and standard‐of‐care tests could detect at least one pathogen in 98% of cases and the mixed viral‐bacterial detection rate was 65%. The positive percent agreement (PPA), and negative percent agreement (NPA) for RP were 94% and 99%; the PPA and NPA for PP were 89% and 98%. The distribution of pathogens was similar in the upper and lower respiratory tracts, and the DNA or RNA copies of pathogens in the lower respiratory tract were equal to or higher than those in the upper respiratory tract. PP detected bacterial pathogens in 40 (67%) cases, and clinicians tended to increase bacterial diagnosis and escalate antimicrobial therapy for them. RP and PP had satisfactory performance to help pediatricians make pathogenic diagnoses and establish therapy earlier. The pathogens in the upper respiratory tract had predictive diagnostic values for lower respiratory tract infections in children with severe CAP.

Background: Pneumonia is a common disease in children, and causes a substantial burden both on patients and health care systems. Comparison between community-acquired pneumonia (CAP) and hospital-acquired pneumonia (HAP) and the prognosticator of hospitalized pneumonia patients in Taiwan is unclear.Materials and Methods: In this retrospective study, data from hospitalized children aged <18 years with a diagnosis of pneumonia from 2012 to 2013 in our institutional database were investigated. Demographic characteristics, laboratory data, identified pathogens, and treatment course was recorded for analysis. A value of P < 0.05 was considered statistically significant.Results: A total of 548 patients with 598 episodes of pneumonia (male/female ratio = 1.08) were enrolled in the database. Underlying diseases are more common in patients with HAP than those with CAP. Patients with HAP had a higher mortality and length of hospital and intensive care unit (ICU) stay than that of those with CAP. C-reactive protein (CRP) and band form plus segment neutrophil percentage were higher in patients with CAP. In multivariate analysis of CAP group, underlying disease, CRP, and band form plus segment neutrophil percentage were independent prognosticators of admission to ICU. Underlying disease and CRP were independent prognosticators of mortality. The most common pathogens were respiratory syncytial virus, Streptococcus pneumoniae, and influenza virus.Conclusions: Patients with HAP had significantly higher mortality rates and longer lengths of hospital and ICU stay than those with CAP. CRP was an independent prognosticator of admission to ICU and mortality in patients with CAP, and also served as a prognosticator of mortality in patients with HAP.

BACKGROUND/PURPOSE:Coronavirus disease 2019 (COVID-19) pandemic challenges pediatric health globally by limited medical accessibility. In response to COVID-19 epidemic in Taiwan, public restrictions were applied and the Level 3 alert was announced from May to July in 2021 for local outbreak. This study aims to analyze patients' clinical features and outcomes in the pediatric intensive care unit (PICU) during the COVID-19 epidemic with the Level 3 alert in Taiwan.METHODS:Medical records were retrospectively collected in patients admitted to the PICU of National Taiwan University Children's Hospital from May to July 2021 (Level 3 alert) and May to July 2019 and 2020 (control periods). Clinical characteristics and outcomes were compared between patients in the period with the Level 3 alert and control periods.RESULTS:During the study period, PICU monthly admissions significantly decreased in the Level 3 alert period and were negatively correlated with monthly newly confirmed COVID-19 cases. Patients admitted during the Level 3 alert were older, had higher disease severity, lower proportion of cardiovascular disease, and higher proportion of hematology-oncology diseases than those in the control group. After adjusting for the above factors, admission during Level 3 alert was an independent factor for higher mortality rate and prolonged length of stay (>14 days) in the PICU.CONCLUSION:During the COVID-19 epidemic with strict public restrictions, critically ill patients admitted to the PICU decreased but had increased disease severity, prolonged length of stay in the PICU, and higher mortality, reflecting the impact of quarantine and limited medical access.

Background Bronchiolitis is a common airway infection in young children. Hemodynamically significant congenital heart disease (CHD) predicts a more complicated course. However, the role of airway anomalies remains unknown. Methods We retrospectively reviewed the records of patients under 2 years old, diagnosed with CHD, and admitted between January 2011 and December 2013, before the palivizumab era. Records of bronchiolitis admissions were also extracted. Patients were grouped according to CHD condition and airway anomalies. Results A total of 230 patients with CHD were enrolled. A total of 180 (78%) and 71 (31%) patients had hemodynamically significant CHD and airway anomalies, respectively. A total of 52 (22.6%) patients were admitted for bronchiolitis 78 times. Among them, 33 (63.5%) had hemodynamically significant CHD, and 28 (53.8%) had airway anomalies. In patients with bronchiolitis admissions, the mean ventilator use, intensive care unit stay, and hospital stay were 1.08, 4.08, and 15.19 days, respectively. When compared, the mean hospital stay for bronchiolitis patients with airway anomalies was significantly longer than that of those without airway anomalies (19.8 vs. 9.9 days, p = 0.008). When further divided the patients by the presence hemodynamic significance, patients with hemodynamically significant CHD and airway anomaly had longer hospital stay than those who had neither. (21.7 vs. 8.3 days, p = 0.004) Airway anomaly was a significant risk factor for longer hospital stay in linear regression model ( p = 0.007). Conclusions Airway anomalies are common in children with CHD and are associated with longer hospital stays on bronchiolitis admission. An active survey for airway anomalies and adequate prophylaxis for bronchiolitis infection might be important in the care of children with CHD associated with airway anomalies.