Clinical aspects of patients visiting the emergency department with febrile seizure

Purpose@#We aimed to analyze the clinical characteristics, recurrence, neurological outcomes, and the impact of coronavirus disease 2019 pandemic in children who visited 2 emergency departments (EDs) with febrile seizure (FS). @*Methods@#We retrospectively reviewed medical records of 3,172 episodes, involving 2,510 children aged 6-60 months whose diagnoses were FSs at the EDs in 2 hospitals from 2013 through 2022. Through the review, we analyzed clinical characteristics and associated factors for the recurrence of FS. As a sub-analysis, the variables were compared between before (2017-2019) and during (2020-2022) the pandemic. @*Results@#A total of 3,172 FS-related visits to the EDs were found in 2,510 children. Of these, 890 children (35.5%) underwent recurrences of FS. The recurrence of FS was associated with boys (63.3% vs. 57.8%; P = 0.007), seizures lasting longer than 5 minutes (16.6% vs. 12.7%; P = 0.007), family history of FS (23.7% vs. 16.2%; P < 0.001), complex FS (13.3% vs. 8.0%; P < 0.001), and epilepsy diagnosed thereafter (9.1% vs. 3.0%; P < 0.001). During the pandemic, we noted a decrease in the number of FS-related visits to the EDs (from 1,274 to 383), an increase in the percentage of complex FS (9.3% vs. 13.8%; P = 0.012), and a decrease in the percentage of recurrent FS (49.4% vs. 33.4%; P < 0.001), compared to before the pandemic. @*Conclusion@#Our study identified factors associated with recurrence of FS, and confirmed the increase in complex FS with the decrease in the recurrence during the coronavirus disease 2019 pandemic. These findings could be helpful when caring for children with FS in EDs.

Major Congenital Anomalies in Korean Livebirths in 2013–2014: Based on the National Health Insurance Database

Background@#In Korea, there have been no reports comparing the prevalence of major congenital anomalies with other countries and no reports on surgical treatment and longterm mortality. We investigated the prevalence of 67 major congenital anomalies in Korea and compared the prevalence with that of the European network of population-based registries for the epidemiological surveillance of congenital anomalies (EUROCAT). We also investigated the mortality and age at death, the proportion of preterm births, and the surgical rate for the 67 major congenital anomalies. @*Methods@#Korean National Health Insurance claim data were obtained for neonates born in 2013–2014 and admitted within one-year-old. Sixty-seven major congenital anomalies were defined by medical diagnoses classified by International Classification of Diseases-10 codes according to the EUROCAT definition version 2014. Mortality and surgery were defined if any death or surgery claim code was confirmed until 2020. Poisson distribution was used to calculate the 95% confidence interval of the congenital anomaly prevalence. @*Results@#The total prevalence of the 67 major anomalies was 433.5/10,000 livebirths. When compared with the prevalence of each major anomaly in EUROCAT, the prevalence of spina bifida, atrial septal defect (ASD), congenital megacolon, hip dislocation and/or dysplasia and skeletal dysplasia were more than five times higher in Korea. In contrast, the prevalence of aortic atresia/interrupted aortic arch and gastroschisis was less than one-fifth in Korea. The proportion of preterm births was 15.7%; however, more than 40% of infants with anencephaly, annular pancreas and gastroschisis were preterm infants. Additionally, 29.2% of the major anomalies were admitted to the neonatal intensive care units at birth, and 25.6% received surgical operation. The mortality rate was 1.7%, and 78.2% of the deaths occurred within the first year of life. However, in neonates with tricuspid valve atresia and stenosis, duodenal atresia or stenosis, and diaphragmatic hernia, more than half died within their first month of life. ASD and ventricular septal defect were the most common anomalies, and trisomy 18 and hypoplastic left heart syndrome were the most fatal anomalies. All infants with aortic atresia/interrupted aortic arch and conjoined twins received surgery. @*Conclusion@#The proportion of surgeries, preterm births and mortality was high in infants with major congenital anomalies. The establishment of a national registry of congenital anomalies and systematic support by national medical policies are needed for infants with major congenital anomalies in Korea.

Application of Machine Learning Approaches to Predict Postnatal Growth Failure in Very Low Birth Weight Infants

Purpose@#The aims of the study were to develop and evaluate a machine learning model with which to predict postnatal growth failure (PGF) among very low birth weight (VLBW) infants. @*Materials and Methods@#Of 10425 VLBW infants registered in the Korean Neonatal Network between 2013 and 2017, 7954 infants were included. PGF was defined as a decrease in Z score >1.28 at discharge, compared to that at birth. Six metrics [area under the receiver operating characteristic curve (AUROC), accuracy, precision, sensitivity, specificity, and F1 score] were obtained at five time points (at birth, 7 days, 14 days, 28 days after birth, and at discharge). Machine learning models were built using four different techniques [extreme gradient boosting (XGB), random forest, support vector machine, and convolutional neural network] to compare against the conventional multiple logistic regression (MLR) model. @*Results@#The XGB algorithm showed the best performance with all six metrics across the board. When compared with MLR, XGB showed a significantly higher AUROC (p=0.03) for Day 7, which was the primary performance metric. Using optimal cut-off points, for Day 7, XGB still showed better performances in terms of AUROC (0.74), accuracy (0.68), and F1 score (0.67). AUROC values seemed to increase slightly from birth to 7 days after birth with significance, almost reaching a plateau after 7 days after birth. @*Conclusion@#We have shown the possibility of predicting PGF through machine learning algorithms, especially XGB. Such models may help neonatologists in the early diagnosis of high-risk infants for PGF for early intervention.

Growth Pattern With Morbidities From Birth to 5 Years of Age in Very Low Birth Weight Infants: Comparison of the Korean National Network and National Health Insurance Service

Background@#Long-term growth data of very low birth weight (VLBW) infants are currently collected in the Korean Neonatal Network (KNN) and National Health Insurance Service (NHIS) database. However, variance in the number of infants, check-up time, and check-up parameters led to decreased credibility of cumulated data. We aimed to compare the data on serial growth outcomes by major morbidities from birth to 5 years in VLBW infants between the KNN and NHIS databases. @*Methods@#We combined the NHIS and KNN data of VLBW infants born between 2013 and 2015. The check-up times in the NHIS database were at 4–6, 9–12, 18–24, 30–36, 42–48, and 54–60 months of age, whereas in the KNN were at 18–24 months of corrected age and at 36 months of age.Result: Among 8,864 VLBW infants enrolled based on the birth certificates from the Statistics Korea, 6,086 infants (69%) were enrolled in the KNN, and 5,086 infants (57%) participated in the NHIS health check-up. Among 6,068 infants, 3,428 infants (56%) were enrolled at a corrected age of 18–24 months and 2,572 infants (42%) were enrolled at a chronological age of 33–36 months according to the KNN follow-up registry. However, based on the national birth statistics data, the overall follow-up rate of the KNN at 36 months of age was as low as 29%. The NHIS screening rate was lower at first (23%); however, it increased over time to exceed the KNN follow-up rate. Growth failure (weight under 10th percentile) at corrected ages of 18–24 months and 36 months were more common in the NHIS than KNN (42% vs. 20%, 37% vs. 34.5%). Infants with bronchopulmonary dysplasia and periventricular leukomalacia showed similar rates of growth failure at 2 years but varying rates at 3 years between the KNN and NHIS. @*Conclusion@#By integrating the KNN and NHIS data indirectly at continuous time points according to morbidities, we found that there are discontinuities and discrepancies between the two databases among VLBW infants. Establishing an integrated system by patient level linking the KNN and NHIS databases can lead to better understanding and improved neonatal outcomes in VLBW infants in Korea.

Survey on the Status of Breastfeeding in Korean Medical Institution Workers

Background@#Human breast milk is essential and provides irreplaceable nutrients for early humans. However, breastfeeding is not easy for various reasons in medical institution environments. Therefore, in order to improve the breastfeeding environment, we investigated the difficult reality of breastfeeding through questionnaire responses from medical institution workers. @*Methods@#A survey was conducted among 179 medical institution workers with experience in childbirth within the last five years. The survey results of 175 people were analyzed, with incoherent answers excluded. @*Results@#Of the 175 people surveyed, a total of 108 people (61.7%) worked during the day, and 33 people (18.9%) worked in three shifts. Among 133 mothers who stayed with their babies in the same nursing room, 111 (93.3%) kept breastfeeding for more than a month, but among those who stayed apart, only 10 (71.4%) continued breastfeeding for more than a month (P = 0.024). Ninety-five (88.0%) of daytime workers, 32 (94.1%) two-shift workers, and 33 (100%) three-shift workers continued breastfeeding for more than a month (P = 0.026). Workers in general hospitals tended to breastfeed for significantly longer than those that worked in tertiary hospitals (P = 0.003). A difference was also noted between occupation categories (P = 0.019), but a more significant difference was found in the comparison between nurses and doctors (P = 0.012). Longer breastfeeding periods were noted when mothers worked three shifts (P = 0.037). Depending on the period planned for breastfeeding prior to childbirth, the actual breastfeeding maintenance period after birth showed a significant difference (P = 0.002). Of 112 mothers who responded to the question regarding difficulties in breastfeeding after returning to work, 87 (77.7%) mentioned a lack of time caused by being busy at work, 82 (73.2%) mentioned the need for places and appropriate circumstances. @*Conclusion@#In medical institutions, it is recommended that environmental improvements in medical institutions, the implementation of supporting policies, and the provision of specialized education on breastfeeding are necessary to promote breastfeeding.

Epidemiology of Macrosomia in Korea: Growth and Development

Background@#Macrosomia, as an infant with birth weight over 4 kg, can have several perinatal, and neonatal complications. This study aimed to estimate the incidence of macrosomia in Korea and to identify the growth and developmental outcomes and other neonatal complications. @*Methods@#In total, 397,203 infants who were born in 2013 with birth weight ≥ 2.5 kg and who underwent infant health check-up between their 1 st and 7 th visit were included from the National Health Insurance Service database. The information was obtained by the International Classification of Diseases-10 codes or self-reported questionnaires in the National Health Screening Program. @*Results@#The distribution of infants by birth weight was as follows: 384,181 (97%) infants in the 2.5–3.99 kg (reference) group, 12,016 (3%) infants in the 4.0–4.49 kg group, 772 (0.2%) infants in the 4.5–4.99 kg group, and 78 (0.02%) infants in the ≥ 5 kg group. Macrosomia showed significantly higher incidence of sepsis, male sex, and mothers with GDM and birth injury. There was a significant difference in weight, height, and head circumference according to age, birth weight group, and combination of age and birth weight, respectively (P < 0.001). The number of infants with the weight above the 90 th percentile in macrosomia at each health check-up showed higher incidence than in reference group. The mean body mass index significantly differed among the groups, as 50.6 in infants with 2.5–3.99 kg of birth weight, 63.5 with 4.0–4.49 kg, 71.0 with 4.5–4.99 kg, and 73.1 with ≥ 5 kg. There was a significant difference in the incidence of poor developmental results between infants with macrosomia and the reference group at 24, 36 and 48 month of age. @*Conclusion@#Macrosomia was significantly associated with the risk of sepsis, birth injury, obesity and developmental problem especially in a boy born from mothers with gestational diabetes mellitus. Careful monitoring and proper strategies for monitoring growth and development are needed.

Hearing Impairments in Preterm Infants: Factors Asso ciated with Discrepancies between Screening and Con firmatory Test Results

Purpose@#The aim of the study was to investigate risk factors of hearing impairments in preterm infants and analyze factors associated with discrepancies between neonatal hearing screening (NHS) and confirmatory test results. @*Methods@#We analyzed the medical records of 352 preterm infants born at 23 to 32 weeks’ gestational age (GA) who underwent both automated auditory brainstem response (aABR) and confirmatory ABR (cABR). @*Results@#Mean GA, mean birth weight, the incidence of small for GA and cesarean section birth were significantly different between the pass and refer groups on aABR and the normal and abnormal groups of cABR. On univariate analysis, bronchopul monary dysplasia (odds ratio [OR], 2.74; 95% confidence interval [CI], 1.00 to 7.48), intraventricular hemorrhage (OR, 7.02; 95% CI, 1.59 to 31.05), and use of furosemide (OR, 3.84; 95% CI, 1.38 to 10.73) were the factors related to refer results on aABR. Peri ventricular leukomalacia (PVL; OR, 4.00; 95% CI, 1.39 to 11.52) and use of vancomycin (OR, 2.86; 95% CI, 1.22 to 6.73) were associated with abnormal cABR. Twenty-five (7.9%) infants had discrepant aABR and cABR results, particularly males and those in whom vancomycin was used. @*Conclusion@#PVL and use of vancomycin were confirmed as independent risk factors for hearing loss in infants born at less than 32 weeks’ GA. Also, discrepancies between the screening and confirmatory test may occur, especially among male infants and those in whom vancomycin was used. The hearing of infants must be assessed more carefully in such groups regardless of NHS results.

Pulmonary Surfactant Replacement Therapy for Respiratory Distress Syndrome in Neonates: a Nationwide Epidemiological Study in Korea

Background@#Pulmonary surfactant (PS) replacement therapy, as a safe and effective treatment for respiratory distress syndrome (RDS) may have further increased with the extended insurance coverage since 2011 in Korea. Thus, this study aimed to investigate the epidemiologic data of PS replacement therapy for RDS in Korea and to analyze the complications associated with RDS. @*Methods@#We included 19,442 infants who were treated with PS and diagnosed with RDS (International Classification of Diseases-10 codes: P22.0) between 2014 and 2018 from the Health Insurance Review and Assessment database. Birth certificate data from Statistics Korea were used to estimate the incidence of RDS. @*Results@#The average incidence of RDS within the study period was 0.99% among live births.Repeated doses of PS were administered to 1,688 infants (8.7%), ranging from 2 doses in 929 infants (4.8%) to 9 doses in 1 infant (0.01%). The incidence of RDS in term infants markedly increased over 5 years from 0.2% to 0.34%. The incidence was similarly increased among the preterm infants. The RDS mortality rate was 6.3% and showed a decreasing trend according to year. The mortality rate was significantly higher in the lower gestational age group. A decreasing trend was observed in the incidence of the complications, such as patent ductus arteriosus, intraventricular hemorrhage, and bronchopulmonary dysplasia, except for pneumothorax in term infants. The complications were also higher in the lower gestational age group and the lower birth weight group. However, pneumothorax was the most frequent complication in the term infant group and in infants with birth weight ≥ 2,500 g. @*Conclusion@#Advancements in neonatal care and extended insurance coverage have increased the use of PS replacement therapy for RDS. This, in turn, decreased neonatal mortality and the incidence of the associated complications. The appropriate therapeutic strategy for RDS should be decided according to the gestational age and lung pathology.

Effect of Nutritional Intervention by the Nutrition Support Team on Postnatal Growth in Preterm Infants

Purpose@#Nutritional intervention by an interdisciplinary nutrition support team (NST) can potentially improve postnatal growth outcomes in preterm infants. This study aimed to measure the growth impact of a nutritional intervention package performed by an NST in a quality improvement effort in a neonatal intensive care unit (NICU). @*Methods@#Fifty-two infants born below 2,000 g and admitted to NICU participated in the Quality Improvement (QI) program between March 2016 and February 2017. The nutritional intervention was applied according to newly established nutritional guidelines on parenteral and enteral nutrition, and an NST performed a weekly nutritional assessment. The Z-scores of weight, height, and head circumference were calculated according to the gestational age and sex. The clinical impact on postnatal growth was compared between the QI and pre-QI groups. The pre-QI group included 69 infants admitted in the same NICU between 2014 and 2015. @*Results@#The time to the initiation of enteral nutrition decreased significantly (P＜0.001). Changes in weight (P=0.027), head circumference (P=0.003), Z-scores between birth, and 40 weeks postconceptional age (PCA) were significantly larger in the QI than the pre-QI group. The percentage of infants weighing below the 10th percentile at one month after birth and at 40 weeks PCA was higher in the pre-QI than the QI group. @*Conclusion@#The implementation of evidence-based best practices for preterm nutrition resulted in significant improvements in the growth outcomes in preterm infants.

Effect of Nutritional Intervention by the Nutrition Support Team on Postnatal Growth in Preterm Infants

Purpose@#Nutritional intervention by an interdisciplinary nutrition support team (NST) can potentially improve postnatal growth outcomes in preterm infants. This study aimed to measure the growth impact of a nutritional intervention package performed by an NST in a quality improvement effort in a neonatal intensive care unit (NICU). @*Methods@#Fifty-two infants born below 2,000 g and admitted to NICU participated in the Quality Improvement (QI) program between March 2016 and February 2017. The nutritional intervention was applied according to newly established nutritional guidelines on parenteral and enteral nutrition, and an NST performed a weekly nutritional assessment. The Z-scores of weight, height, and head circumference were calculated according to the gestational age and sex. The clinical impact on postnatal growth was compared between the QI and pre-QI groups. The pre-QI group included 69 infants admitted in the same NICU between 2014 and 2015. @*Results@#The time to the initiation of enteral nutrition decreased significantly (P＜0.001). Changes in weight (P=0.027), head circumference (P=0.003), Z-scores between birth, and 40 weeks postconceptional age (PCA) were significantly larger in the QI than the pre-QI group. The percentage of infants weighing below the 10th percentile at one month after birth and at 40 weeks PCA was higher in the pre-QI than the QI group. @*Conclusion@#The implementation of evidence-based best practices for preterm nutrition resulted in significant improvements in the growth outcomes in preterm infants.

Evaluation of Newborn Infants with Prenatally Diagnosed Congenital Pulmonary Airway Malformation: A Single-Center Experience

PURPOSE: Congenital pulmonary airway malformation (CPAM)—a rare developmental anomaly—affects the lower respiratory tract in newborns. By comparing the reliability of diagnostic tools and identifying predictive factors for symptoms, we provide comprehensive clinical data for the proper management of CPAM. METHODS: We reviewed the medical records of 66 patients with prenatally diagnosed CPAM delivered at Severance Children's Hospital between January 2005 and July 2017. RESULTS: We enrolled 33 boys and 33 girls. Their mean gestational age and birth weight were 38.8 weeks and 3,050 g, respectively. Prenatal ultrasonography and postnatal radiography, lung ultrasonography, and chest computed tomography (CT) showed inconsistent findings. Chest CT showed superior sensitivity (100%) and positive predictive value (90%). Among the 66 patients, 59 had postnatally confirmed CPAM, three had pulmonary sequestration, one had cystic teratoma, and one had a normal lung. Of the 59 patients with CPAM, 21 (35%; mean age, 23.4 months) underwent surgery, including 15 who underwent video-assisted thoracoscopy. Twenty-five and 12 patients exhibited respiratory symptoms at birth and during infancy, respectively. Apgar scores and mediastinal shift on radiography were significantly associated with respiratory symptoms at birth. However, none of the factors could predict respiratory symptoms during infancy. CONCLUSION: Radiography or ultrasonography combined with chest CT can confirm an unclear or inconsistent lesion. Apgar scores and mediastinal shift on radiography can predict respiratory symptoms at birth. However, symptoms during infancy are not associated with prenatal and postnatal factors. Chest CT combined with periodic symptom monitoring is important for diagnosing and managing patients with prenatally diagnosed CPAM and to guide appropriate timing of surgery.

Successful Treatment of Neonatal Pylorospasm with Intravenous Atropine

Pylorospasm is a cause of delayed gastric emptying in young infants. As in patients with hypertrophic pyloric stenosis, most pylorospasm patients present with projectile vomiting. However, unlike that in case of hypertrophic pyloric stenosis, no persistent pyloric stenotic lesions are present. As such, follow-up using serial gastrointestinal fluoroscopy or ultrasonography can be helpful in diagnosing patients with clinical signs of gastroparesis. Most cases can be treated conservatively, but some patients require pharmacologic treatment. Antispasmodics have been proposed as a treatment for pylorospasm, but their use in neonates and infants has rarely been reported. Herein, we present a case of pylorospasm diagnosed in the neonatal period and successfully treated with intravenous atropine.

The impact of a quality improvement effort in reducing admission hypothermia in preterm infants following delivery / 소아과

PURPOSE: Hypothermia at admission is associated with increased mortality and morbidity in preterm infants. We performed a quality improvement (QI) effort to determine the impact of a decrease in admission hypothermia in preterm infants. METHODS: The study enrolled very low birth weight (VLBW) infants born at Gangnam Severance Hospital between January 2013 and December 2016. This multidisciplinary QI effort included the use of occlusive wraps, warm blankets, and caps; the delivery room temperature was maintained above 23.0℃, and a check-list was used for feedback. RESULTS: Among 259 preterm infants, the incidence of hypothermia (defined as body temperature <36.0℃) decreased significantly from 68% to 41%, and the mean body temperature on neonatal intensive care unit admission increased significantly from 35.5℃ to 36.0℃. In subgroup analysis of VLBW infants, admission hypothermia and neonatal outcomes were compared between the pre-QI (n=55) and post-QI groups (n=75). Body temperature on admission increased significantly from 35.4℃ to 35.9℃ and the number of infants with hypothermia decreased significantly from 71% to 45%. There were no cases of neonatal hyperthermia. The incidence of pulmonary hemorrhage was significantly decreased (P=0.017). Interaction analysis showed that birth weight and gestational age were not correlated with hypothermia following implementation of the protocol. CONCLUSION: Our study demonstrated a significant reduction in admission hypothermia following the introduction of a standardized protocol in our QI effort. This resulted in an effective reduction in the incidence of massive pulmonary hemorrhage.

A New Integrated Newborn Screening Workflow Can Provide a Shortcut to Differential Diagnosis and Confirmation of Inherited Metabolic Diseases

PURPOSE: We developed a new workflow design which included results from both biochemical and targeted gene sequencing analysis interpreted comprehensively. We then conducted a pilot study to evaluate the benefit of this new approach in newborn screening (NBS) and demonstrated the efficiency of this workflow in detecting causative genetic variants. MATERIALS AND METHODS: Ten patients in Group 1 were diagnosed clinically using biochemical assays only, and 10 newborns in Group 2 were diagnosed with suspected inherited metabolic disease (IMD) in NBS. We applied NewbornDiscovery (SD Genomics), an integrated workflow design that encompasses analyte-phenotype-gene, single nucleotide variant/small insertion and deletion/copy number variation analyses along with clinical interpretation of genetic variants related to each participant's condition. RESULTS: A molecular genetic diagnosis was established in 95% (19/20) of individuals. In Group 1, 13 and 7 of 20 alleles were classified as pathogenic and likely pathogenic, respectively. In Group 2, 11 and 6 of 17 alleles with identified causative variants were pathogenic and likely pathogenic, respectively. There were no variants of uncertain significance. For each individual, the NewbornDiscovery and biochemical analysis results reached 100% concordance, since the single newborn testing negative for causative genetic variant in Group 2 showed a benign clinical course. CONCLUSION: This integrated diagnostic workflow resulted in a high yield. This approach not only enabled early confirmation of specific IMD, but also detected conditions not included in the current NBS.

National Registry Data from Korean Neonatal Network: Two-Year Outcomes of Korean Very Low Birth Weight Infants Born in 2013–2014

BACKGROUND: The aim of this study was to observe long-term outcomes of very low birth weight infants (VLBWIs) born between 2013 and 2014 in Korea, especially focusing on neurodevelopmental outcomes. METHODS: The data were collected from Korean Neonatal Network (KNN) registry from 43 and 54 participating units in 2013 and 2014, respectively. A standardized electronic case report form containing 30 items related to long-term follow up was used after data validation. RESULTS: Of 2,660 VLBWI, the mean gestational age and birth weight were 291/7 ± 26/7 weeks and 1,093 ± 268 g in 2013 and 292/7 ± 26/7 weeks and 1,125 ± 261 g in 2014, respectively. The post-discharge mortality rate was 1.2%–1.5%. Weight < 50th percentile was 46.5% in 2013 and 66.1% in 2014. The overall prevalence of cerebral palsy among the follow up infants was 6.2% in 2013 and 6.6% in 2014. The Bayley Scales of Infant Developmental Outcomes version II showed 14%–25% of infants had developmental delay and 3%–8% of infants in Bayley version III. For the Korean developmental screening test for infants and children, the area “Further evaluation needed” was 5%–12%. Blindness in both eyes was reported to be 0.2%–0.3%. For hearing impairment, 0.8%–1.9% showed bilateral hearing loss. Almost 50% were readmitted to hospital with respiratory illness as a leading cause. CONCLUSION: The overall prevalence of long-term outcomes was not largely different among the VLBWI born between 2013 and 2014. This study is the first large national data study of long-term outcomes.

Effective Tidal Volume for Normocapnia in Very-Low-Birth-Weight Infants Using High-Frequency Oscillatory Ventilation

PURPOSE: Removal of CO₂ is much efficient during high-frequency oscillatory ventilation (HFOV) for preterm infants. However, an optimal carbon dioxide diffusion coefficient (DCO₂) and tidal volume (VT) have not yet been established due to much individual variance. This study aimed to analyze DCO₂ values, VT, and minute volume in very-low-birth-weight (VLBW) infants using HFOV and correlates with plasma CO₂ (pCO₂). MATERIALS AND METHODS: Daily respiratory mechanics and ventilator settings from twenty VLBW infants and their two hundred seventeen results of blood gas analysis were collected. Patients were treated with the Dräger Babylog VN500 ventilator (Drägerwerk Ag & Co.) in HFOV mode. The normocapnia was indicated as pCO₂ ranging from 45 mm Hg to 55 mm Hg. RESULTS: The measured VT was 1.7 mL/kg, minute volume was 0.7 mL/kg, and DCO₂ was 43.5 mL²/s. Mean results of the blood gas test were as follows: pH, 7.31; pCO₂, 52.6 mm Hg; and SpO₂, 90.5%. In normocapnic state, the mean VT was significantly higher than in hypercapnic state (2.1±0.5 mL/kg vs. 1.6±0.3 mL/kg), and the mean DCO₂ showed significant difference (68.4±32.7 mL²/s vs. 32.4±15.7 mL²/s). The DCO₂ was significantly correlated with the pCO₂ (p=0.024). In the receiver operating curve analysis, the estimated optimal cut-off point to predict the remaining normocapnic status was a VT of 1.75 mL/kg (sensitivity 73%, specificity 80%). CONCLUSION: In VLBW infants treated with HFOV, VT of 1.75 mL/kg is recommended for maintaining proper ventilation.

Percutaneous Transhepatic Biliary Drainage in a Two-Month-Old Infant with Inspissated Bile Syndrome

Inspissated bile syndrome (IBS) is a relatively rare condition. Many treatment options are available, including medication, surgery, and surgical interventions, such as insertion of cholecystostomy drain, endoscopic retrograde cholangiopancreatography, internal biliary drainage, and percutaneous transhepatic biliary drainage (PTBD). We herein report the first case of IBS that was successfully treated with PTBD in a two-month-old infant in Korea. PTBD was initiated on postnatal day 72. On postnatal day 105, we confirmed complete improvement and successfully removed the catheters. This report suggests that PTBD is a viable and safe treatment option for obstructive jaundice in very young infants.

Clinical Pharmacokinetics of Caffeine in Korean Preterm Infants with Apnea of Prematurity

PURPOSE: Caffeine shows wide interindividual pharmacokinetic (PK) variation, and therapeutic drug monitoring (TDM) may be needed. The PK profile of caffeine in Korean preterm neonates was investigated, and factors influencing the clearance of caffeine were analyzed. METHODS: Fifty-nine preterm neonates receiving caffeine for apnea of prematurity were enrolled in the study (gestational age, 29.5±2.2 weeks and birth weight [BW], 1,318±358 g). Caffeine (20 mg/kg) was intravenously administered to each neonate as a loading dose, followed by a maintenance dose of 5-10 mg/kg/d. A total of 190 serum concentrations were measured for population PK analysis and modeling using nonlinear mixed-effects model (NONMEM®) software. RESULTS: The mean serum concentration of caffeine was 15.4±4.5 mg/L (range 7.8-33.0 mg/L). High serum concentrations (>20 mg/L) were noted in 36 samples (29%). At the first measurement of serum caffeine, the mean postmenstrual age was 33.9±2.3 weeks, mean BW was 1,802±471 g, mean duration of treatment was 7.4±9.4 days, and mean sampling time after the last dose was 21.8±2.1 hours. In the population PK analysis, the clearance was 0.033 L/h and volume of distribution was 0.371 L. Typical clearance was calculated as 0.0293×(BW/70)1.33. Among the subjects receiving 5 mg/kg/d caffeine, the most significant risk factor associated with high serum concentrations (>20 mg/L) was low BW (P=0.024). CONCLUSION: BW was the only covariate that influenced caffeine clearance in preterm neonates. Preterm neonates with low BW should be carefully monitored for apnea and adverse reactions in addition to undergoing TDM.

Postdischarge growth assessment in very low birth weight infants / 소아과

PURPOSE: The goal of nutritional support for very-low-birth-weight (VLBW) infants from birth to term is to match the in utero growth rates; however, this is rarely achieved. METHODS: We evaluated postdischarge growth patterns and growth failure in 81 Korean VLBW infants through a retrospective study. Weight and height were measured and calculated based on age percentile distribution every 3 months until age 24 months. Growth failure was defined as weight and height below the 10th percentile at 24 months. For the subgroup analysis, small-for-gestational age (SGA) and extremely low birth weight (ELBW) infants were evaluated. The growth patterns based on the Korean, World Health Organization (WHO), or Centers for Disease Control and Prevention (CDC) standard were serially compared over time. RESULTS: At postconception age (PCA) 40 weeks, 47 (58%) and 45 infants (55%) showed growth failure in terms of weight and height, respectively. At PCA 24 months, 20 infants (24%) showed growth failure for weight and 14 (18%) for height. Growth failure rates were higher for the SGA infants than for the appropriate-weight-for-gestational age infants at PCA 24 months (P=0.045 for weight and P=0.038 for height). Growth failure rates were higher for the ELBW infants than for the non-ELBW infants at PCA 24 months (P<0.001 for weight and P=0.003 for height). Significant differences were found among the WHO, CDC, and Korean standards (P<0.001). CONCLUSION: Advancements in neonatal care have improved the catch-up growth of VLBW infants, but this is insufficient. Careful observation and aggressive interventions, especially in SGA and ELBW infants, are needed.

Experience and pharmacokinetics of Levetiracetam in Korean neonates with neonatal seizures / 소아과

PURPOSE: The aims of this study were to evaluate the safety and pharmacokinetics of levetiracetam (LEV) in neonates with seizures and to establish a population pharmacokinetics (PPK) model by using the software NONMEM. METHODS: A retrospective analysis of 18 neonatal patients with seizures, who were treated with LEV, including 151 serum samples, was performed. The mean loading dose was 20 mg/kg, followed by a mean maintenance dose of 29 mg/kg/day. RESULTS: Seventeen neonates (94%) had seizure cessation within 1 week and 16 (84%) remained seizure-free at 30 days under the LEV therapy. The mean serum concentration of LEV was 8.7 µg/mL. Eight samples (5%) were found above the therapeutic range. No serious adverse effects were detected. In the PPK analysis for Korean neonates, the half-life was 9.6 hours; clearance, 0.357 L/hr; and volume of distribution, 4.947 L, showing differences from those in adults. CONCLUSION: LEV is a safe and effective option for the treatment of neonatal seizures with careful therapeutic drug monitoring.