Soon Min Lee

Surfactant lavage therapy for meconium aspiration syndrome: a systematic review and meta-analysis.

Background: Lung lavage with diluted surfactant has emerged as an innovative treatment for meconium aspiration syndrome (MAS). However, the treatment effect has not yet been fully established. Objective: To investigate the effects of surfactant lavage therapy for MAS by a systematic meta-analysis. Methods: Relevant studies were identified by database searches in MEDLINE (from 1950), EMBASE (from 1980), and CENTRAL, up to June 2010, and by additional hand searches. Meta-analyses were separately conducted for randomized controlled trials (RCTs) and non-randomized controlled studies (NRSs). Risk of bias was assessed and clinical as well as statistical heterogeneities were also investigated in explaining the potential bias. Results: Two RCTs (87 patients) and eight NRSs (178 patients) were identified. From the results of the meta-analysis of RCTs, surfactant lavage significantly decreased death or the need for extracorporeal membrane oxygenation (RR 0.34, 95% CI 0.11, 0.99). An interventional benefit was indicated for other outcomes, although it was not statistically significant based only on the two RCTs. Results from the analysis of outcomes from NRSs are consistent with those from RCTs and demonstrated a beneficial effect, which could be considered as supporting evidence. Conclusions: Lung lavage with diluted surfactant appeared to improve the clinical outcome in infants with MAS. Given that less than 100 infants were included in the two RCTs, the findings of this study may still be regarded as insufficient evidence. Further research will be needed to confirm the benefit as well as to refine the lavage technique.

New Power Quality Index in a Distribution Power System by Using RMP Model

In this paper, a new power quality index (PQI), which is directly related to the generation of distortion power from nonlinear harmonic loads, is introduced to determine their harmonic pollution ranking in a distribution power system. The electric load composition rate (LCR) and the total harmonic distortion (THD) for the estimated currents on each harmonic load are used to define the proposed PQI. The reduced multivariate polynomial (RMP) model with one-shot training property is applied to realize the PQI. Then, the ranking of distortion power for each nonlinear load, which has adverse effect on the entire system, is determined. It is proven that the relative ranking based on the PQI matches that based on the distortion power directly computed from each harmonic load.

Usefulness of the delta neutrophil index for assessing neonatal sepsis

We investigated the significance of the calculated delta neutrophil index (DNI) as a diagnostic factor for neonatal sepsis.

Kalman-Filter-Based Multilevel Analysis to Estimate Electric Load Composition

This paper presents a novel method by the multilevel analysis (MLA) to estimate the composition rate of electric loads with respect to measured total current waveform by improving the performance of a previous estimation scheme proposed by the authors. The proposed MLA makes it possible to analyze the electric load composition rate (LCR), which indicates the portions of several typical loads connected to a single point of common coupling (PCC), with the partition of several levels. Then, the Kalman-filter (KF) algorithm is applied to solve the estimation problem of LCR based on formulation with current waveforms in each level. The effectiveness of MLA based on the KF in practice is verified by the experimental implementation based on the prototypes setup in laboratory. It consists of a 3-kW photovoltaic grid-connected inverter, which contributes to a small distortion in voltage at PCC, and practical nonlinear loads connected to PCC. Also, the harmonic-current-injection-model-based time-domain simulations are carried out to prove the potential of the proposed method under various circumstances with different nonlinear loads.

A Case of Suspected Isotretinoin-Induced Malformation in a Baby of a Mother Who Became Pregnant One Month after Discontinuation of the Drug

Isotretinoin is a known human teratogen that can cause multiple malformations. At present, women who conceive one cycle after discontinuing isotretinoin are told that their teratogenic risk is not higher than baseline. We present a case of both ear malformation in a newborn whose mother had taken isotretinoin for 2 years until one month prior to the time when she became pregnant. We suggest that further studies of pharmacokinetics and malformation of isotreinoin are needed.

A Reduced Multivariate Polynomial Model for Estimation of Electric Load Composition

This paper describes the estimation of the electric load composition on a consumer side of a distributed power system. The purpose of the estimation is to determine the amount of each load class with respect to the total electric current waveform from instrument readings. For this analysis, the reduced multivariate polynomial (RMP) model is applied when the distributed power system has the electric loads supplied from different voltage levels through a non-ideal transformer. The estimation problem in this study is also considered in relation to the power quality issue.

Survival analysis of spinal muscular atrophy type I.

Purpose The life expectancy of patients with spinal muscular atrophy (SMA) type I is generally considered to be less than 2 years. Recently, with the introduction of proactive treatments, a longer survival and an improved survival rate have been reported. In this study, we analyzed the natural courses and survival statistics of SMA type I patients and compared the clinical characteristics of the patients based on their survival periods. Methods We reviewed the medical records of 14 pediatric patients diagnosed with SMA type I during a 9-year period. We examined the demographic and clinical characteristics of these patients, calculated their survival probabilities, and plotted survival curves as on the censoring date, January 1, 2010. We also compared the characteristics of the patients who died before the age of 24 months (early-death, ED group) and those who survived for 24 months or longer (long-survival, LS group). Results The mean survival time was 22.8±2.0 months. The survival probabilities at 6 months, 12 months, 18 months, 24 months, and 30 months were 92.9%, 92.9%, 76.0%, 76.0%, and 65.1%, respectively. Birth weight was the only factor that showed a statistically significant difference between the ED and LS groups (P=0.048). Conclusion In this study, the survival probabilities at 2 years were far greater than expected. Because of the limited number of patients and information in this study, the contribution of improved supportive care on longer survival could not be clarified; this may be elucidated in larger cohort studies.

Blood Culture Proven Early Onset Sepsis and Late Onset Sepsis in Very-Low-Birth-Weight Infants in Korea

Neonatal sepsis remains one of the most important causes of death and co-morbidity in very-low-birth-weight (VLBW) infants. The aim of this study was to determine the current incidences of early-onset sepsis (EOS) and late-onset sepsis (LOS), the distribution of pathogens, and the impact of infection on co-morbidities in VLBW infants. We analyzed the data including sepsis episode from 2,386 VLBW infants enrolled in Korean Neonatal Network from January 2013 to June 2014. We defined EOS as a positive blood culture occurring between birth and 7 days of life and LOS after 7 days of life. Sepsis was found in 21.1% of VLBW infants. The risk of sepsis was inversely related to birth weight and gestational age. EOS was found in only 3.6% of VLBW infants, however the mortality rate was as high as 34.1%. EOS was associated with the increased odds for bronchopulmonary dysplasia and intraventricular hemorrhage. The vast majority of EOS was caused by Gram-positive organisms, particularly coagulase-negative staphylococci (30.6%). LOS developed in 19.4% of VLBW infants with a 16.1% mortality rate. Pathogens in LOS were dominated by coagulase-negative staphylococci (38.3%). Twenty-five percent and fifty percent of first LOS episode occurred after 12 days and 20 days from birth, respectively. Younger and smaller VLBW infants showed the earlier occurrence day for the 25% of first LOS episode. This study provides a recent nationwide epidemiology of sepsis in VLBW infants in Korea. Based on this study, successful strategies to reduce infections would improve survival and reduce morbidity.

Effects of cytochrome P450 (CYP)2C19 polymorphisms on pharmacokinetics of phenobarbital in neonates and infants with seizures

Background Phenobarbital (PB), commonly used as the preferred treatment for neonatal seizure, is a drug that requires careful dose adjustments based on therapeutic drug monitoring. It has been reported that PB metabolism was affected by cytochrome P450 (CYP)2C19 polymorphisms in adults requiring dose adjustment. Aim This study aimed to evaluate the effects of CYP2C19 genetic polymorphisms on PB pharmacokinetics (PK) in neonates and infants with seizures. Methods CYP2C19 (wild type: CYP2C19*1/*1, heterozygous extensive metabolisers: CYP2C19*1/*2, *1/*3 and poor metabolisers: CYP2C19*2/*2, *2/*3) genetic polymorphisms in 52 neonates and infants with seizures were analysed. PK parameters were compared based on genotypes. The NONMEM program was used for population PK modelling. Results No significant difference in PB clearance (CL), volume of distribution (Vd) and concentrations were shown among the CYP2C19 genotype groups. The results of PK modelling were as follows: Vd=3590 ×(body weight (BWT)/4)0.766 ×(AGE/2)0.283 and CL=32.6×(BWT/4)1.21. Conclusions PB PK parameters of neonates and infants with seizures were not significantly different among the groups with different CYP2C19 genotypes. The addition of CYP2C19 genotyping to PK models did not improve the dosing strategies in neonates and infants.

Doppler ultrasonographic detection of nutcracker syndrome in a young child with intussusception: A case report

UNLABELLED We report on a 2-y-old male with intussusception accompanying nutcracker syndrome detected by renal Doppler ultrasound. Renal Doppler ultrasound revealed a significant difference in the peak velocity between the hilar and aortomesenteric portions of the left renal vein. CONCLUSION Renal Doppler ultrasound has been very useful and effective in detecting nutcracker syndrome in a young child.