Expert opinion on evidence after the 2020 Korean Cardiopulmonary Resuscitation Guidelines: a secondary publication.

Considerable evidence has been published since the 2020 Korean Cardiopulmonary Resuscitation Guidelines were reported. The International Liaison Committee on Resuscitation (ILCOR) also publishes the Consensus on CPR and Emergency Cardiovascular Care Science with Treatment Recommendations (CoSTR) summary annually. This review provides expert opinions by reviewing the recent evidence on CPR and ILCOR treatment recommendations. The authors reviewed the CoSTR summary published by ILCOR in 2021 and 2022. PICO (patient, intervention, comparison, outcome) questions for each topic were reviewed using a systemic or scoping review methodology. Two experts were appointed for each question and reviewed the topic independently. Topics suggested by the reviewers for revision or additional description of the guidelines were discussed at a consensus conference. Forty-three questions were reviewed, including 15 on basic life support, seven on advanced life support, two on pediatric life support, 11 on neonatal life support, six on education and teams, one on first aid, and one related to COVID-19. Finally, the current Korean CPR Guideline was maintained for 28 questions, and expert opinions were suggested for 15 questions.

Five-year follow-up of phase II trial of stromal cells for bronchopulmonary dysplasia.

BACKGROUND: We previously performed a phase II randomised double-blind clinical trial of mesenchymal stromal cell (MSCs) transplantation to prevent bronchopulmonary dysplasia in extremely premature infants. Subsequently, we followed the infants enrolled in this clinical trial to determine the safety and effectiveness of MSCs against bronchopulmonary dysplasia at 5-year follow-up. METHODS: We evaluated infants at 5 years of age receiving placebo or MSCs in a prospective follow-up study. RESULTS: In terms of the primary end point of composite respiratory morbidities, including respiratory problem-related readmission, emergency department visits or oxygen therapy, the MSC group had a rate of 60.7% for composite morbidities, while the control group showed a tendency of higher rate of 83.9% for the same outcomes without statistical significance. In terms of the secondary outcomes, the MSC group infants showed a tendency of being less likely to visit emergency department (control 67.7% vs MSC 35.7%) and to receive oxygen therapy (control 29.0% vs MSC 3.6%). No difference was observed in the incidence of respiratory problem-related hospital readmission or wheezing episodes between the groups. CONCLUSION: Intratracheally instilled MSCs showed the possibility of potential to decrease respiratory symptom-related emergency department visits and oxygen therapy episodes in infants born extremely preterm during the 5 years after a phase II randomised controlled, double-blind trial of MSCs transplantation for bronchopulmonary dysplasia. This small size study suggests preliminary insights that can be further tested using larger sample sizes. TRIAL REGISTRATION NUMBER: NCT01897987.

Breastfeeding and vitamin D.

The recent re-emergence of vitamin D deficiency (VDD) and rickets among breastfed infants without adequate sunlight exposure and vitamin D supplementation has been reported worldwide. Breastfed infants are particularly vulnerable to VDD because of the low vitamin D content of breast milk, restricted sunlight exposure, increased pollution, and limited natural dietary sources of vitamin D. The prevalence of VDD in breastfed infants differs vastly between studies and nations at 0.6%-91.1%. The recommended intake of vitamin D for lactating mothers to optimize their overall vitamin D status and, consequently, of their breast milk is 200-2,000 IU/day, indicating a lack of consensus. Some studies have suggested that maternal high-dose vitamin D supplementation (up to 6,400 IU/day) can be used as an alternate strategy to direct infant supplementation. However, concern persists about the safety of maternal high-dose vitamin D supplementation. Direct infant supplementation is the currently available option to support vitamin D status in breastfed infants. The recommended dose for vitamin D supplementation in breastfed infants according to various societies and organizations worldwide is 200-1,200 IU/day. Most international guidelines recommend that exclusively or partially breastfed infants be supplemented with 400 IU/day of vitamin D during their first year of life. However, domestic studies on the status and guidelines for vitamin D in breastfed infants are insufficient. This review summarizes the prevalence of VDD in breastfed infants, vitamin D content of breast milk, and current guidelines for vitamin D supplementation of lactating mothers and infants to prevent VDD in breastfed infants.

Stem cells for bronchopulmonary dysplasia in preterm infants: A randomized controlled phase II trial.

We previously demonstrated the safety and feasibility of mesenchymal stem cell (MSC) transplantation for bronchopulmonary dysplasia (BPD) in preterm infants in a phase I clinical trial. We thus investigated the therapeutic efficacy of MSCs for BPD in premature infants. A phase II double-blind, randomized, placebo-controlled clinical trial was conducted on preterm infants at 23 to 28 gestational weeks (GW) receiving mechanical ventilator support with respiratory deterioration between postnatal days 5 and 14. Infants were stratified by 23 to 24 GW and 25 to 28 GW and randomly allocated (1:1) to receive stem cells (1 × 107 cells/kg, n = 33) or placebo (n = 33). Although the inflammatory cytokines in the tracheal aspirate fluid were significantly reduced with MSCs, the primary outcome of death or severe/moderate BPD in the control group (18/33, 55%) was not significantly improved with MSC transplantation (17/33, 52%). In the subgroup analysis, the secondary outcome of severe BPD was significantly improved from 53% (8/15) to 19% (3/16) with MSC transplantation in the 23 to 24 GW group but not in the 25 to 28 GW subgroup. In summary, although MSC transplantation might be safe and feasible, this small study was underpowered to detect its therapeutic efficacy in preterm infants at 23 to 28 GW. Accordingly, we are now conducting an additional larger and controlled phase II clinical trial focusing on infants at 23 to 24 GW (NCT03392467). ClinicalTrials.gov identifier: NCT01828957.

Epidemiology of respiratory syncytial virus infection in infants born at less than thirty-five weeks of gestational age.

BACKGROUND: The aims of this study were to observe the respiratory syncytial virus (RSV) hospitalization rate and to identify the risk factors for hospitalization for RSV infection among infants in Korea born at <35 weeks of gestational age and who had not previously received palivizumab. METHODS: We conducted a study over a 2.5-year period (between April 2007 and September 2009) that included premature infants (<35 weeks of gestational age) who underwent follow-up during 1 year after discharge from the neonatal intensive care unit. Demographic information was collected for each subject at baseline, and the reasons for hospitalization were obtained during the 1-year follow-up period. RESULTS: The study population included 1022 subjects who completed follow-up interviews. Eight hundred seventeen infants were included in analysis for RSV hospitalization. Excluded from the study were 167 subjects with chronic lung disease who had received palivizumab prophylaxis and 38 subjects who were not tested for RSV. The overall incidence of RSV hospitalization in the group that did not receive palivizumab was 4.5% (37 of 817 patients). Independent risk factors associated with RSV hospitalization were multiple gestation (P = 0.022) and longer duration of mechanical ventilation in the neonatal intensive care unit (P = 0.039). CONCLUSION: This study showed the epidemiology and risk factors of RSV hospitalization in preterm infants in Korea. RSV infection was one of the main causes of hospitalization after discharge from the neonatal intensive care unit in patients born at <35 weeks of gestational age.

An 18-year experience of tracheoesophageal fistula and esophageal atresia.

PURPOSE: To determine the clinical manifestations and outcomes of patients with tracheoesophageal fistula (TEF) and esophageal atresia (EA) born at a single neonatal intensive care unit. METHODS: A retrospective analysis was conducted for 97 patients with confirmed TEF and EA who were admitted to the neonatal intensive care unit between 1990 and 2007. RESULTS: The rate of prenatal diagnosis was 12%. The average gestational age and birth weight were 37(+2) weeks and 2.5±0.7 kg, respectively. Thirty-one infants were born prematurely (32%). Type C was the most common. The mean gap between the proximal and distal esophagus was 2 cm. Esophago-esophagostomy was performed in 72 patients at a mean age of 4 days after birth; gastrostomy or duodenostomy were performed in 8 patients. Forty patients exhibited vertebral, anorectal, cardiac, tracheoesophageal, renal, limb (VACTERL) association with at least 2 combined anomalies, and cardiac anomaly was the most common. The most common post-operative complications were esophageal stricture followed by gastroesophageal reflux. Balloon dilatation was performed for 1.3 times in 26 patients at a mean age of 3 months. The mortality and morbidity rates were 24% and 67%, respectively, and the most common cause of death was sepsis. The weight of approximately 40% patients was below the 10th percentile at 2 years of age. CONCLUSION: Mortality and morbidity rates of patients with TEF and EA are high as compared to those of infants with other neonatal surgical diseases. Further efforts must be taken to reduce mortality and morbidity and improve growth retardation.

Experience with meconium peritonitis.

BACKGROUND: Meconium peritonitis is a sterile chemical peritonitis resulting from intrauterine bowel perforation. With the development of neonatal care, the prognosis of meconium peritonitis improved much. We report our clinical experience. METHODS: The medical records of patients with meconium peritonitis admitted to the Asan Medical Center from June 1989 to July 2006 were retrospectively reviewed. RESULTS: Of 41 patients (17 males, 24 females), 38 (92.7%) were suspected to suffer from meconium peritonitis prenatally, at a median gestational age of 32 weeks (range, 21-40 weeks). The most common prenatal sonographic finding was fetal ascites followed by dilated bowel. Ten patients were managed conservatively, but 31 patients underwent operations including resection and anastomosis (22), drainage procedure (4), ileostomy (3) and primary repair (2). The operative 31 cases comprised generalized (16), fibroadhesive (10), and cystic types (5). The main causes were intestinal atresia and idiopathic bowel perforation. The mortality rate was 2.4%, and the morbidity rate was 34.1%. CONCLUSIONS: Good survival rate was achieved. But there was rather high morbidity. More gentle and delicate approach should be done to lower the morbidity.

Transfusion-related cytomegalovirus infection among very low birth weight infants in an endemic area.

This study investigated the incidence of acquired cytomegalovirus (CMV) infection in very low birth weight infants (VLBWI) given CMV seropositive blood, and sought to determine whether filtering and irradiation of blood products could help prevent CMV infection and the time required to clear passively-derived anti-CMV IgG among 80 VLBWI transfused with filtered-irradiated blood, 20 VLBWI transfused with nonfiltered- nonirradiated blood and 26 nontransfused VLBWI. CMV IgG and IgM values were obtained from all blood products prior to transfusions, and from VLBWI at birth until the infants became seronegative. Urine was obtained for CMV culture at birth and every 3-4 weeks until 12 weeks after the final transfusion. The incidence of CMV IgG seropositivity among the 126 infants at birth and the blood products given were 96% and 95%, respectively. The incidence of acquired CMV infection was 4/100 (4%) in the transfused group: 2/80 (2.5%) and 2/20 (10%) in the filtered-irradiated and nonfiltered-nonirradiated transfusion groups, respectively. Approximately 9-10 months elapsed to clear passively acquired CMV IgG. The irradiation and filtering of the blood products did not seem to decrease the transfusion-related CMV infection rate in Korea among VLBWI, however, further validation is recommended in a larger cohort of infants.