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Background: Congenital heart diseases (CHDs), particularly atrial and ventricular septal defects, pose significant health risks and common challenges in detection via echocardiography. Doctors often employ the cardiac structural information during the diagnostic process. However, prior CHD research has not determined the influence of including cardiac structural information during the labeling process and the application of data augmentation techniques. Methods: This study utilizes advanced artificial intelligence (AI)-driven object detection frameworks, specifically You Look Only Once (YOLO)v5, YOLOv7, and YOLOv9, to assess the impact of including cardiac structural information and data augmentation techniques on the identification of septal defects in echocardiographic images. Results: The experimental results reveal that different labeling strategies substantially affect the performance of the detection models. Notably, adjustments in bounding box dimensions and the inclusion of cardiac structural details in the annotations are key factors influencing the accuracy of the model. The application of deep learning techniques in echocardiography enhances the precision of detecting septal heart defects. Conclusions: This study confirms that careful annotation of imaging data is crucial for optimizing the performance of object detection algorithms in medical imaging. These findings suggest potential pathways for refining AI applications in diagnostic cardiology studies.

Doctors conventionally analyzed echocardiographic images for diagnosing congenital heart diseases (CHDs). However, this process is laborious and depends on the experience of the doctors. This study investigated the use of deep learning algorithms for the image detection of the ventricular septal defect (VSD), the most common type. Color Doppler echocardiographic images containing three types of VSDs were tested with color doppler ultrasound medical images. To the best of our knowledge, this study is the first one to solve this object detection problem by using a modified YOLOv4–DenseNet framework. Because some techniques of YOLOv4 are not suitable for echocardiographic object detection, we revised the algorithm for this problem. The results revealed that the YOLOv4–DenseNet outperformed YOLOv4, YOLOv3, YOLOv3–SPP, and YOLOv3–DenseNet in terms of metric mAP-50. The F1-score of YOLOv4-DenseNet and YOLOv3-DenseNet were better than those of others. Hence, the contribution of this study establishes the feasibility of using deep learning for echocardiographic image detection of VSD investigation and a better YOLOv4-DenseNet framework could be employed for the VSD detection.

Kawasaki disease (KD) typically occurs in children aged under 5 years and can cause coronary artery lesions (CALs). Early diagnosis and treatment with intravenous immunoglobulin can reduce the occurrence of CALs; therefore, identifying a good biomarker for diagnosing KD is essential. Here, using next-generation sequencing in patients with recurrent KD, those with viral infection, and healthy controls, we identified dysregulated circulating microRNAs as diagnostic biomarkers for KD. Pathway enrichment analysis illustrated the putative role of these miRNAs in KD progression. Their expression levels were validated using real-time polymerase chain reaction (qPCR). Fifteen dysregulated circulating miRNAs (fold changes >2 and p < 0.001). Receiver operating characteristic analysis revealed that high miR-24-3p expression levels may be a potential biomarker for KD diagnosis. In conclusion, we identified miR-24-3p significantly higher in KD patients, which may be a potential diagnostic biomarker for KD.

Abstract Riociguat, a soluble guanylate cyclase stimulator, is approved for treatment of adults with pulmonary arterial hypertension (PAH). The safety, tolerability, and pharmacokinetics (PK) of oral riociguat in a pediatric population with PAH was assessed in PATENT–CHILD (NCT02562235), a multicenter, single‐arm, 24‐week, open‐label, Phase 3 study. Patients aged 6–17 years in World Health Organization functional class (WHO‐FC) I–III treated with stable endothelin receptor antagonists and/or prostacyclin analogs received riociguat equivalent to 0.5–2.5 mg three times daily in adults, as either oral pediatric suspension or tablets, based on bodyweight. Primary outcomes were safety, tolerability, and PK of riociguat. Twenty‐four patients (mean age 12.8 years), 18 of whom were in WHO‐FC II, were enrolled. Adverse events (AEs), mostly mild or moderate, were reported in 20 patients (83%). Four patients (17%) experienced a serious AE; all resolved by study end and two (8%) were considered study‐drug related. Hypotension was reported in three patients and hemoptysis in one (all mild/moderate intensity). Riociguat plasma concentrations in pediatric patients were consistent with those published in adult patients. From baseline to Week 24, mean ± standard deviation increase in 6‐minute walking distance was 23 ± 69 m (n = 19), and mean decrease in NT‐proBNP was –66 ± 585 pg/ml (n = 14). There was no change in WHO‐FC. Two patients experienced clinical worsening events of hospitalization for right heart failure. PK results confirmed a suitable riociguat dosing strategy for pediatric patients with PAH. The data suggest an acceptable safety profile with potential efficacy signals.

ObjectiveKawasaki disease (KD) is the most common form of pediatric vasculitis. We evaluated the influence of KD on cardiopulmonary function and analyzed the echocardiographic findings of patients with KD through serial follow-ups from childhood to adolescence.MethodsThis was a retrospective study. We recruited patients with KD after the acute stage who underwent at least two (with >1-year interval between visits) cardiopulmonary exercise testing (CPET) and echocardiographic examinations in the last 10 years. Cardiopulmonary function was determined through CPET on a treadmill. The maximum Z score (Max-Z) of the proximal left anterior descending coronary artery or right coronary artery was determined using echocardiography. Healthy peers matched for age, sex, and body mass index with serial CPET and echocardiographic data were recruited as a control group.ResultsEach group consisted of 30 participants with comparable basic characteristics. No significant differences in the variables of the first CPET were observed between the two groups. In the final CPET, the control group had a higher percentage of measured oxygen consumption (Vo2) at the anaerobic threshold (AT) to the predicted peak Vo2 (p = 0.016), higher percentage of measured peak Vo2 to the predicted peak Vo2 (p = 0.0004), and higher Vo2 at AT (p < 0.0001) than those of the KD group. No significant difference in the percentage of distribution of Max-Z was observed between the first and final echocardiographic examinations.ConclusionsChildren with a history of KD had comparable exercise capacity to their healthy peers. However, in the follow-up, the aerobic metabolism and peak exercise load capacities of adolescents with KD were significantly lower than those of control adolescents.

Individuals with mitral valve prolapse (MVP) have exercise intolerance even without mitral valve regurgitation. Mitral valve degeneration may progress with aging. We aimed to evaluate the influence of MVP on the cardiopulmonary function (CPF) of individuals with MVP through serial follow-ups from early to late adolescence. Thirty patients with MVP receiving at least two cardiopulmonary exercise tests (CPETs) using a treadmill (MVP group) were retrospectively analyzed. Age-, sex-, and body mass index-matched healthy peers, who also had serial CPETs, were recruited as the control group. The average time from the first CPET to the last CPET was 4.28 and 4.06 years in the MVP and control groups, respectively. At the first CPET, the MVP group had a significantly lower peak rate pressure product (PRPP) than the control group (p = 0.022). At the final CEPT, the MVP group had lower peak metabolic equivalent (MET, p = 0.032) and PRPP (p = 0.031). Moreover, the MVP group had lower peak MET and PRPP as they aged, whereas healthy peers had higher peak MET (p = 0.034) and PRPP (p = 0.047) as they aged. Individuals with MVP had poorer CPF than healthy individuals as they develop from early to late adolescence. It is important for individuals with MVP to receive regular CPET follow-ups.

Pulmonary stenosis (PS) affects cardiopulmonary function and exercise performance. Cardiopulmonary exercise testing (CPET) together with transthoracic echocardiography (TTE) can measure exercise performance, PS progression, and treatment effects. We assessed exercise capacity in PS patients using these methods. We enrolled 28 PS patients aged 6–35 years who received surgery, balloon pulmonary valvuloplasty, and follow-up care. The control population was selected by a 1:1 matching on age, sex, and body mass index. Baseline and follow-up peak pulmonary artery pulse wave velocity (PAV) were compared using TTE. Initial CPET revealed no significant differences in anaerobic metabolic equivalent (MET), peak oxygen consumption (VO2), and heart rate recovery between the two groups, nor were significant differences in pulmonary function identified. Within the PS group, there were no significant differences in MET, peak VO2, and heart rate recovery between the baseline and final CPET. Similarly, no significant differences were observed between the baseline and final PAV. The exercise capacity of patients with properly managed PS was comparable to that of healthy individuals. However, during the follow-up, declining trends in pulmonary function, aerobic metabolism, and peak exercise load capacity were observed among adolescents with PS. This study provides long-term data suggesting that PS patients should be encouraged to perform physical activity. Regular reevaluation should also be encouraged to limit performance deterioration.

Vascular endothelial growth factor (VEGF) is an important factor in mediating the inflammation of Kawasaki disease (KD). The literature regarding the relationship between VEGF and KD is sparse. The purpose of this study was to investigate the correlation of VEGF and KD. In a prospective study of 42 Taiwanese KD patients (18.9 ± 12.2 months, M/F 22/20) treated with intravenous immunoglobulin (IVIG), a series of VEGF levels was measured from the acute to convalescent phases. KD patients were classified into two subgroups with (n =20) and without (n = 22) acute coronary artery lesions (CALs). Control samples were obtained from 30 febrile controls (19.1 ± 13.7 months, M/F 13/17). In KD patients, VEGF levels in the pre-IVIG acute phase were significantly higher than those in the subacute and convalescent phases (both p < 0.001). In KD patients with CALs, VEGF levels significantly increased immediately in the post-IVIG phase (p = 0.039), and then significantly decreased in the subacute phase (p = 0.002). KD patients with acute CALs had higher median VEGF levels than those without acute CALs from acute to convalescent phases. In the subacute phase, KD patients with acute CALs had significantly higher VEGF levels (p = 0.022) than those without acute CALs. Our data show that VEGF did not decrease after IVIG treatment, and increased significantly after IVIG treatment in KD patients with acute CALs in acute phase. VEGF might be related to the complications of CALs in KD patients.

BackgroundKawasaki disease is the most common cause of acquired heart disease among febrile children under the age of 5 years old. It is also a clinically diagnosed disease. In this study, we developed and assessed a novel score system using objective parameters to differentiate Kawasaki disease from febrile children.MethodsWe analyzed 6,310 febrile children and 485 Kawasaki disease subjects in this study. We collected biological parameters of a routine blood test, including complete blood count with differential, C-reactive protein, aspartate aminotransferase, and alanine aminotransferase. Receiver operating characteristic curve, logistic regression, and Youden's index were all used to develop the prediction model. Two other independent cohorts from different hospitals were used for verification.ResultsWe obtained eight independent predictors (platelets, eosinophil, alanine aminotransferase, C-reactive protein, hemoglobin, mean corpuscular hemoglobin, mean corpuscular hemoglobin concentration, and monocyte) and found the top three scores to be eosinophil >1.5% (score: 7), alanine aminotransferase >30 U/L (score: 6), and C-reactive protein>25 mg/L (score: 6). A score of 14 represents the best sensitivity value plus specificity prediction rate for Kawasaki disease. The sensitivity, specificity, and accuracy for our cohort were 0.824, 0.839, and 0.838, respectively. The verification test of two independent cohorts of Kawasaki disease patients (N = 103 and 170) from two different institutes had a sensitivity of 0.780 (213/273).ConclusionOur findings demonstrate a novel score system with good discriminatory ability for differentiating between children with Kawasaki disease and other febrile children, as well as highlight the importance of eosinophil in Kawasaki disease. Using this novel score system can help first-line physicians diagnose and then treat Kawasaki disease early.

BACKGROUND:The myocardial adaptive mechanism in patients with repaired tetralogy of Fallot (rTOF) is less understood. We aimed to investigate biventricular myocardial adaptive remodeling in rTOF patients. METHODS:We recruited 32 rTOF patients and 38 age- and sex-matched normal controls. The pulmonary stenosis of rTOF patients was measured using catheterized pressure gradient between right ventricle (RV) and pulmonary artery (PGRVPA). rTOF patients with PGRVPA < 15 mmHg and ≥15 mmHg were classified as low pulmonary stenosis (rTOFlow, n = 19) and high pulmonary stenosis (rTOFhigh, n = 13) subgroups, respectively. Magnetic resonance imaging tissue phase mapping was employed to evaluate the voxelwise biventricular myocardial motion in longitudinal (Vz), radial (Vr), and circumferential (Vφ) directions. RESULTS:The rTOFlow subgroup presented higher pulmonary regurgitation fraction than rTOFhigh subgroup (p < 0.001). Compared with the normal group, only rTOFlow subgroup presented a decreased RV ejection fraction (RVEF) (p < 0.05). The rTOFlow subgroup showed decreased systolic and diastolic Vz in RV and LV, whereas rTOFhigh subgroup showed such change only in RV. In rTOFlow subgroup, RVEF significantly correlated with RV systolic Vr (r = 0.56, p < 0.05), whereas LVEF correlated with LV systolic Vz (r = 0.51, p = 0.02). Prolonged QRS correlated with RV systolic Vr (r = -0.58, p < 0.01) and LV diastolic Vr (r = 0.81, p < 0.001). No such correlations occurred in rTOFhigh subgroup. CONCLUSIONS:The avoidance of unfavorable functional interaction in RV and LV in rTOFhigh subgroup suggested that adequate pulmonary stenosis (PGRVPA ≥ 15 mmHg in this sereis) has a protective effect against pulmonary regurgitation.

Abstract Background Kawasaki disease (KD) patients could develop coronary artery lesion (CAL) which threatens children's life. A previous study identified KD biomarker miRNAs that could discriminate KD patients from febrile non‐KD patients. We wonder whether these KD prediction biomarkers could be further applied to predict CAL formation in KD patients. Methods To examine this hypothesis, we conducted a meta‐analysis, miRNA mimic transfection, in vitro cell model and microarray assays. Results We first showed that miR‐182‐5p and miR‐183‐5p kept higher levels in the KD patients with CAL than those without CAL (p

Autoimmune encephalitis (AE) is a severe neurological disease. The brain of the AE patient is attacked by a dysregulated immune system, which is caused by the excessive production of autoantibodies against neuronal receptors and synaptic proteins. AE is also characterized by the uncontrolled B lymphocyte infiltration through the blood–brain barrier (BBB) layer, and the investigation of the underlying mechanism involved in this infiltration may facilitate the discovery of novel therapies for AE. However, few AE-related studies have focused on this issue. In this study, we aimed to identify the factors involved in B lymphocyte infiltration in AE. For this purpose, we first enrolled four healthy control and five AE subjects, collecting their serum and/or total white blood cell samples. The white blood cell samples were further used for collecting RNA and DNA. Then, we simulated the in vivo B lymphocyte infiltration with an in vitro leukocyte transendothelial migration model. It turned out that AE serum treatment significantly and specifically promoted B cells to penetrate the BBB endothelial layer without affecting neutrophils. Next, through genome-wide DNA methylation assays on bisulfite-conversion DNA samples, we identified S100A6 and S100A11 as potential hypo-methylated disease genes in the AE samples. Further qPCR assays demonstrated their upregulation in AE samples, reflecting the negative correlations between gene expression and DNA methylation. Finally, recombinant S100A6 protein treatment significantly increased B lymphocyte infiltration through the BBB endothelial layer, which partially recapitulated the effect of AE serum. In summary, by using an in vitro leukocyte transendothelial migration model, we confirmed that S100A6 promoted B lymphocyte to penetrate the BBB endothelial layer, which is similar to the in vivo clinical manifestations of AE. Therefore, further studies on how the S100A6 protein facilitates B lymphocyte infiltration and on whether other factors in serum also contribute to this phenomenon are likely to improve our understanding of AE and hopefully to reveal novel therapeutic targets for this emerging treatable neurological disorder.

A quick prediction method may help confirm the diagnosis of Kawasaki disease (KD), and reduce the risk of coronary artery lesions. The purpose of this study was to evaluate potential candidate diagnostic serum proteins in KD using isobaric tagging for relative and absolute quantification (iTRAQ) gel-free proteomics. Ninety two subjects, including 68 KD patients (1.6 ± 1.2 years, M/F 36/32) and 24 fever controls with evident respiratory tract infection (2.1 ± 1.2 years, M/F 13/11) were enrolled. Medical records were reviewed for demographic and laboratory data. The iTRAQ gel-free proteomics was used to screen serum proteins completely and compare the difference between two groups followed by specific validation with ELISA. The candidate proteins and conventional laboratory items were selected for the prediction model of KD diagnosis by support vector machine. Five selected candidate proteins, including protein S100-A8, protein S100-A9, protein S100-A12, neutrophil defensin 1, and alpha-1-acid glycoprotein 1 were identified for developing the prediction model of KD diagnosis. They were used to develop an efficient KD prediction model with an area under receiver operating characteristic (auROC) value of 0.92 (95% confidence interval: 0.84, 0.98). These protein biomarkers were significantly correlated with the conventional laboratory items as follows: C-reactive protein, glutamic pyruvic transaminase, white blood count, platelet, segment and hemoglobin. These conventional laboratory items were used to develop a prediction model of KD diagnosis with an auROC value of 0.88 (95% confidence interval: 0.80, 0.96). Our result demonstrated that the prediction model with combined five selected candidate protein levels may be a good diagnostic tool of KD. Further prediction model with combined six conventional laboratory data is also an acceptable alternative method for KD diagnosis.

(1) Background: Desquamation is a common characteristic of Kawasaki disease (KD). In this study, we analyzed patients’ varying desquamation levels in their hands or feet, in correlation with clinical presentation, to assess the relationship. (2) Methods: We retrospectively reviewed children with KD. We analyzed their age, laboratory data before intravenous immunoglobulin (IVIG) treatment and coronary artery abnormalities (CAA) based on the desquamation level of their hands and feet. We classified the desquamation level from 0 to 3 and defined high-grade desquamation as grade 2 and 3. (3) Results: We enrolled a total 112 patients in the study. We found the hands’ high-grade desquamation was positively associated with age and segmented neutrophil percentage (p = 0.047 and 0.029, respectively) but negatively associated with lymphocyte and monocyte percentage (p = 0.03 and 0.006, respectively). Meanwhile, the feet’s high-grade desquamation was positively associated with total white blood cell counts (p = 0.033). Furthermore, we found that high-grade hand desquamation had less probability of CAA formation compared with that of a low grade (7.1% vs. 40.8%, p = 0.016). (4) Conclusions: This report is the first to demonstrate that the desquamation level of hands or feet in KD is associated with different coronary artery abnormalities and laboratory findings.

The usual initial dose of prostaglandin E1 (PGE1) for ductal-dependent congenital heart disease (CHD) is 50–100 ng/kg/minute. The aim of this study was to review our experience of a low initial dose of PGE1 treatment in early newborns with congenital heart disease and patent ductus arteriosus (PDA)-dependent pulmonary flow. Methods: We reviewed the clinical data of 33 newborns with CHD and PDA-dependent pulmonary circulation who were admitted from January 2005 to December 2010. Clinical parameters were collected, including, PGE1 dosage, oxygenation condition, vital signs, and other related clinical parameters during admission. Echocardiography was employed to assess the status of the PDA as clinically indicated. Results: Thirty-three newborns, including 17 males and 16 females, with CHD and PDA-dependent pulmonary circulation were enrolled in the study. Their mean age was 2.9 ± 5.1 (within the range of 1–26) days with a median of 1.0 day. Among the 33 cases, 25 were diagnosed with pulmonary atresia and eight with critical pulmonary stenosis. Twenty-five of our patients were treated with the initial low-dosage regimen of 20.0 ± 7.4 ng/kg/minute in our neonatal intensive care unit. None of these 25 patients with had significant apnea necessitating intubation and none had hypotension, fever, convulsion or cortical hyperostosis. Three of the eight patients who were treated with high-dose PGE1 (39 ± 13.2 ng/kg/minute) before referral to our unit had apnea and intubation after PGE1 use. All patients had adequate PDA patency with a low maintenance dose of 10.5 ± 5.3 ng/kg/minute before operation under our protocol. Conclusion: In our experience, adequate PDA flows in early newborns with CHD and PDA-dependent pulmonary circulation could be achieved at a much lower dose than recommended in the literature. The lower dose of PGE1 also causes much fewer complications, such as apnea, fever, and hypotension. For early newborns with CHD and PDA-dependent pulmonary circulation, treatment with a lower initial dose of PGE1 of 20 ng/kg/minute and a maintenance dose of 10 ng/kg/minute is recommended.

Background Vaccination is one of the best ways to control the SARS-CoV-2 outbreak. In Taiwan, healthcare workers were prioritized for vaccination, but the effectiveness of these vaccines for them remains unclear. Thus, it’s essential to examine their neutralizing antibodies after prime-boost vaccinations.Methods In this prospective observational study, 514 healthcare workers from Chang Gung Memorial hospitals in Taiwan were included between 19 March 2021 and 21 August 2021. The two doses of COVID-19 vaccines were either a match or a mixing of AZD1222 and mRNA-1273, e.g. AZD1222 + AZD1222 (n = 406), mRNA-1273 + mRNA-1273 (n = 62), and AZD1222 + mRNA-1273 (n = 46). Blood specimens were drawn after two doses of vaccines, defined as post-vaccine days [median 34.00 days and interquartile range (IQR) 29.00–42.00 days], and examined for the neutralizing antibodies via SARS-CoV-2 neutralization kits. The results were analyzed as a percentage of inhibition based on the negative control.Results After 2 vaccination doses, subjects with AZD1222 + mRNA-1273 (median 97.15%, IQR 96.06–98.06%) and mRNA-1273 + mRNA-1273 (median 97.47%, IQR 96.75–97.89%) exhibited higher neutralizing antibodies than those receiving AZD1222 + AZD1222 vaccines (median 71.28%, IQR 49.39–89.70%) (the percentage was referred to inhibition of surrogate virus). The post-vaccination days negatively impacted the neutralizing antibodies, except for the mRNA-1273 + mRNA-1273 group. The presence of fever, headache, and myalgia after the second dosage was reflected in the higher neutralizing antibodies (median of no fever 76.00% vs. fever 97.00%, p

We aimed to investigate which factors are associated with coronary artery lesions (CALs) during the acute and chronic stages in Taiwanese children with Kawasaki disease (KD). A total of 216 children with KD were enrolled. Clinical and laboratory data were obtained for each child within 7 days of illness. The patients were classified into KD children without acute CALs (n=135) and those with acute CALs (n=81) according to echocardiography data at Week 2 after treatment. Then, KD children with acute CALs were further divided into those without chronic CALs (n=55) and with chronic CALs (n=26) according to annual echocardiography data. During acute stage of KD, neutrophil count (

To investigate parents’ views about new vaccines, we surveyed the attitudes and awareness toward immunization program among parents of children younger than 14 years in Taiwan. Methods: Parents of children were invited to complete a questionnaire in a tertiary referral medical center in Kaoshiung, southern Taiwan from 2006 to 2008. A total of 535 questionnaires were completed. We used descriptive data for the analysis of parents’ views and attitudes toward the current vaccination program in Taiwan. Results: Of the 535 respondents, most parents (93%) did not think the current vaccination program was satisfactory. Few (approximately 8%) preferred self-paid vaccines. About 63% of parents believed that the new (self-paid) vaccines provided more protection, whereas 48% deemed them too expensive. The most popular reason for preferring the new vaccines was greater protection (73%). One-half of parents considered the new vaccines to be expensive. Regarding parental awareness of side effect of vaccination, fever was the most well known and of greatest concern (91%). Most parents (68%) had good awareness of conjugated pneumococcal vaccines, and only few (13%) had heard of the human papilloma virus vaccine. Most parental information of vaccines came from pamphlets at the hospital (56%). Conclusion: We found the awareness of parents about new vaccines to be insufficient. They also considered the new vaccines to be expensive.

Recent advances in multi-slice computed tomography (MSCT) and three-dimensional computed tomography (3D CT) provide good-resolution images and short scan time for complete diagnosis of congenital heart disease (CHD). In the present study, we found that MSCT rapidly provides clinically relevant information for diagnosing extracardiac vascular anatomy in neonates with CHD. It is less invasive, necessitating only minimum or no sedation and a relatively small amount of contrast material. These advantages are crucial, especially for critically ill neonates. Methods: Between January 2007 and December 2008, MSCT scans were conducted on 41 neonates who were admitted to our neonatal intensive care unit. All the neonates were suspected to have complex CHD after an initial echocardiography examination. The scans were focused on detecting extracardiac vascular anatomy and abnormalities. All the image data sets were sent to image processing workstations for multiplanar interactive viewing and 3D reconstruction. Results: High-resolution MSCT scan images were obtained from 41 patients. Reported indications and findings of extracardiac abnormalities and related structural anatomy pertaining to congenital heart disease from MSCT and 3D CT findings were confirmed by clinical and surgical findings by a team of multidisciplinary congenital heart disease specialists. Conclusion: Based on clinical and surgical confirmation of the MSCT scan results from a multidisciplinary congenital heart disease specialist team, we concluded that adequate information on CHD, specifically that regarding extracardiac abnormalities of the anatomy, can be obtained and MSCT can be used to replace cardiac catheterization.

There has been concern over the effect of vigorous bubbling on the delivery pressure during the operation of the bubble nasal continuous positive airway pressure (CPAP) system. We investigated the relationship between intra-tubing pressure changes and flow rates in a closed bubble CPAP system in vitro. Methods: Using an experimental (in vitro) model, the distal connecting tube of the CPAP system was immersed under the water seal to a depth of 5 cm. Sixteen different flow rates, ranging from 2 L/min to 20 L/min, were tested. The procedure was repeated 10 times at each flow rate, and the intra-tubing pressure was recorded. Results: The intra-tubing pressure within the model increased as the air flow rates were adjusted from 2 L/min to 20 L/min. The relationship was represented by the following equation, pressure (cmH2O) = 5.37 + 0.15 × flow rate (L/min) (R2 = 0.826, p < 0.001). Conclusion: These results demonstrated that the intra-tubing pressure in a bubble CPAP system was highly correlated with flow rate in vitro.

Previous studies have demonstrated a positive correlation between foot length (FL) and birth body weight (BBW), birth body length (BBL), and head circumference (HC). However, there is no data on birth FL in Taiwan. The aim of this study was to evaluate FL measurement in Taiwanese neonates as a method of estimating other anthropometric indices. Methods: In this retrospective study, we enrolled 256 babies born at our hospital and Kaohsiung Veterans General Hospital from 2003-2005. Medical records were reviewed for sex, BBW, BBL, HC, gestational age, and birth FL. Ill newborns, small-for-gestational-age babies, or those with poor birth footprints were excluded. FL at birth was measured from the center of the back of the heel to the tip of the big toe. Linear regression analysis was used to investigate the relation of FL to BBW and BBL. The intraclass correlation coefficient was used to assess inter-rater reliability. Results: A total of 256 babies were reviewed. There were 136 male and 120 female neonates. The gestational age was 38.5 ± 1.3 (mean ± standard deviation) weeks, ranging from 35-42 weeks. The BBW was 3137 ± 396 g. The BBL was 51.1 ± 2.1 cm. The HC was 33.5 ± 1.7 cm. The FL was 7.4 ± 0.46 cm. The regression equation for BBW (y) on FL (x) was as follows: y = 486.2 + 360.4x (p < 0.001, r = 0.421). The regression equation for BBL (y) on FL (x) was as follows: y = 40.1 + 1.45x (p < 0.001, r = 0.305). The regression equation for HC (y) on FL (x) was as follows: y = 14.8 + 2.53x (p < 0.001, r = 0.423). FL showed excellent reliability, with an intraclass correlation coefficient of 0.965 (p < 0.001). Conclusion: Our study demonstrated a significant degree of correlation between FL and BBW, BBL and HC. However, it did not reliably estimate BBW, BBL, or HC—the three anthropometric indices were weakly correlated (r < 0.5) with FL.