PURPOSE: In this study, we investigated the clinical features and prognostic factors of early-onset sepsis (EOS) in neonatal intensive care unit (NICU) patients. METHODS: A retrospective analysis was conducted on medical records from January 2010 to June 2017 (7.5 years) of a university hospital NICU. RESULTS: There were 45 cases of EOS (1.2%) in 3,862 infants. The most common pathogen responsible for EOS was group B Streptococcus (GBS), implicated in 10 cases (22.2%), followed by Escherichia coli, implicated in 9 cases (20%). The frequency of gram-positive sepsis was higher in term than in preterm infants, whereas the rate of gram-negative infection was higher in preterm than in term infants (P < 0.05). The overall mortality was 37.8% (17 of 45), and 47% of deaths occurred within the first 3 days of infection. There were significant differences in terms of gestational age (26.8 weeks vs. 35.1 weeks) and birth weight (957 g vs. 2,520 g) between the death and survival groups. After adjustments based on the difference in gestational age and birth weight between the 2 groups, gram-negative pathogens (odds ratio [OR], 42; 95% confidence interval [CI], 1.4–1,281.8) and some clinical findings, such as neutropenia (OR, 46; 95% CI, 1.3–1,628.7) and decreased activity (OR, 34; 95% CI, 1.8–633.4), were found to be associated with fatality. CONCLUSION: The common pathogens found to be responsible for EOS in NICU patients are GBS and E. coli. Gram-negative bacterial infections, decreased activity in the early phase of infection, and neutropenia were associated with poor outcomes.
Birth Weight ; Escherichia coli ; Gestational Age ; Gram-Negative Bacterial Infections ; Humans ; Infant ; Infant, Newborn ; Infant, Premature ; Intensive Care, Neonatal* ; Medical Records ; Mortality ; Neutropenia ; Prognosis ; Retrospective Studies ; Sepsis* ; Streptococcus

BACKGROUND: Preterm infants have difficulty maintaining body temperature after birth. However, clinical guidelines advocate that neonatal body temperature should be maintained at 36.5°C–37.5°C. PURPOSE: We aimed to investigate the incidence of admission hypothermia in very low birth weight (VLBW) infants and to determine the association of admission temperature with in-hospital mortality and morbidities. METHODS: A cohort study using prospectively collected data involving 70 neonatal intensive care units (NICUs) that participate in the Korean Neonatal Network. From registered infants born between January 2013 and December 2015, 5,343 VLBW infants born at less than 33 weeks of gestation were reviewed. RESULTS: The mean admission temperature was 36.1°C±0.6°C, with a range of 31.9°C to 38.4°C. Approximately 74.1% of infants had an admission hypothermia of <36.5°C. Lower birth weight, intubation in the delivery room and Apgar score <7 at 5 minutes were significantly related to admission hypothermia. The mortality was the lowest at 36.5°C–37.5°C and adjusted odd ratios for all deaths increased to 1.38 (95% confidence interval [CI], 1.04–1.83), 1.44 (95% CI, 1.05–1.97) and 1.86 (95% CI, 1.22–2.82) for infants with admission temperatures of 36.0°C–36.4°C, 35.0°C–35.9°C, and <35.0°C, respectively. Admission hypothermia was also associated with high likelihoods of bronchopulmonary dysplasia, pulmonary hypertension, proven sepsis, pulmonary hemorrhage, air-leak, seizure, grade 3 or higher intraventricular hemorrhage and advanced retinopathy of prematurity requiring laser therapy. CONCLUSION: A large portion of preterm infants in Korea had hypothermia at NICU admission, which was associated with high mortality and several important morbidities. More aggressive interventions aimed at reducing hypothermia are required in this high-risk population.
Apgar Score ; Birth Weight ; Body Temperature ; Bronchopulmonary Dysplasia ; Cohort Studies ; Delivery Rooms ; Hemorrhage ; Hospital Mortality ; Humans ; Hypertension, Pulmonary ; Hypothermia ; Incidence ; Infant ; Infant, Newborn ; Infant, Premature ; Infant, Very Low Birth Weight ; Intensive Care Units ; Intensive Care Units, Neonatal ; Intubation ; Korea ; Laser Therapy ; Mortality ; Parturition ; Pregnancy ; Prospective Studies ; Retinopathy of Prematurity ; Seizures ; Sepsis

PURPOSE: This study aimed to investigate the incidence and clinical features of late-onset circulatory collapse (LCC) in preterm infants. METHODS: Medical records of 327 preterm infants (born before 32 gestational weeks) admitted to the neonatal intensive care unit of Seoul National University Bundang Hospital between January 2014 and December 2017 were reviewed. LCC was defined as sudden onset of refractory hypotension occurring after 7 days of life without obvious causes, which responded to glucocorticoid administration. Clinical characteristics and outcomes in infants with LCC were compared with those in infants with hypotension associated with identifiable causes, which developed after 7 days of life. RESULTS: Among 327 preterm infants who enrolled in this study, 65 infants developed hypotension with oliguria after 7 days of life. Among these 65 infants, 35 (53.8%) met the criteria for LCC and 30 (46.2%) were diagnosed with hypotension associated with other identifiable causes. No statistically significant differences were observed in the baseline pre- and perinatal characteristics between infants with LCC and those with hypotension associated with other causes. Infants with hypotension associated with other causes showed a higher mortality rate than those with LCC (33.3% vs. 5.7%, P=0.004). The mean gestational age and birth weight of infants with LCC were 27+5±2+1 weeks and 963±245 g, respectively. LCC occurred at a mean postnatal age of 18 days. The median body weight at the time of diagnosis of LCC was 1,200 g. No association was observed between LCC and gestational age. CONCLUSION: Among preterm infants born before 32 gestastional weeks who developed hypotension after 7 days of life, nearly 50% were diagnosed with LCC without apparent identifiable causes. Infants with LCC showed a lower mortality rate than those with hypotension associated with other causes.
Birth Weight ; Body Weight ; Diagnosis ; Gestational Age ; Humans ; Hydrocortisone ; Hypotension ; Incidence ; Infant ; Infant, Newborn ; Infant, Premature ; Intensive Care, Neonatal ; Medical Records ; Mortality ; Oliguria ; Seoul ; Shock

PURPOSE: Despite the increasing use of continuous renal replacement therapy (CRRT) in the neonatal intensive care unit (NICU), few studies have investigated its use in preterm infants. This study evaluated the prognosis of preterm infants after CRRT and identified risk factors of mortality after CRRT. MATERIALS AND METHODS: A retrospective review was performed in 33 preterm infants who underwent CRRT at the NICU of Samsung Medical Center between 2008 and 2017. Data of the demographic characteristics, predisposing morbidity, cardiopulmonary function, and CRRT were collected and compared between surviving and non-surviving preterm infants treated with CRRT. Univariable and multivariable analyses were performed to identify factors affecting mortality. RESULTS: Compared with the survivors, the non-survivors showed younger gestational age (29.3 vs. 33.6 weeks), lower birth weight (1359 vs. 2174 g), and lower Apgar scores at 1 minute (4.4 vs. 6.6) and 5 minutes (6.5 vs. 8.6). At the initiation of CRRT, the non-survivors showed a higher incidence of inotropic use (93% vs. 40%, p=0.017) and fluid overload (16.8% vs. 4.0%, p=0.031). Multivariable analysis revealed that fluid overload >10% at CRRT initiation was the primary determinant of mortality after CRRT in premature infants, with an adjusted odds ratio of 14.6 and a 95% confidence interval of 1.10–211.29. CONCLUSION: Our data suggest that the degree of immaturity, cardiopulmonary instability, and fluid overload affect the prognosis of preterm infants after CRRT. Preventing fluid overload and earlier initiation of CRRT may improve treatment outcomes.
Birth Weight ; Gestational Age ; Humans ; Incidence ; Infant, Newborn ; Infant, Premature ; Intensive Care, Neonatal ; Mortality ; Odds Ratio ; Prognosis ; Renal Replacement Therapy ; Retrospective Studies ; Risk Factors ; Survivors

BACKGROUND: To investigate the incidence of surgical intervention in very low birth weight (VLBW) infants and the impact of surgery on neurodevelopmental outcomes at corrected ages (CAs) of 18–24 months, using data from the Korean Neonatal Network (KNN). METHODS: Data from 7,885 VLBW infants who were born and registered with the KNN between 2013 to 2016 were analyzed in this study. The incidences of various surgical interventions and related morbidities were analyzed. Long-term neurodevelopmental outcomes at CAs of 18–24 months were compared between infants (born during 2013 to 2015, n = 3,777) with and without surgery. RESULTS: A total of 1,509 out of 7,885 (19.1%) infants received surgical interventions during neonatal intensive care unit (NICU) hospitalization. Surgical ligation of patent ductus arteriosus (n = 840) was most frequently performed, followed by laser therapy for retinopathy of prematurity and laparotomy due to intestinal perforation. Infants who underwent surgery had higher mortality rates and greater neurodevelopmental impairment than infants who did not undergo surgery (P value < 0.01, both). On multivariate analysis, single or multiple surgeries increased the risk of neurodevelopmental impairment compared to no surgery with adjusted odds ratios (ORs) of 1.6 with 95% confidence interval (CI) of 1.1–2.6 and 2.3 with 95% CI of 1.1–4.9. CONCLUSION: Approximately one fifth of VLBW infants underwent one or more surgical interventions during NICU hospitalization. The impact of surgical intervention on long-term neurodevelopmental outcomes was sustained over a follow-up of CA 18–24 months. Infants with multiple surgeries had an increased risk of neurodevelopmental impairment compared to infants with single surgeries or no surgeries after adjustment for possible confounders.
Cohort Studies ; Ductus Arteriosus, Patent ; Follow-Up Studies ; Hospitalization ; Humans ; Incidence ; Infant ; Infant, Newborn ; Infant, Very Low Birth Weight ; Intensive Care, Neonatal ; Intestinal Perforation ; Korea ; Laparotomy ; Laser Therapy ; Ligation ; Mortality ; Multivariate Analysis ; Odds Ratio ; Retinopathy of Prematurity

BACKGROUND: This study was performed to determine survival and morbidity rates in very low birth weight infants (VLBWIs) in the Korean Neonatal Network (KNN), and to compare neonatal outcomes with those in other countries. METHODS: Data were collected for 8,269 VLBWIs with gestational age (GA) ≥ 22 weeks who were born between January 1, 2013 and December 31, 2016, and admitted to the neonatal intensive care units of the KNN. RESULTS: The survival rate of all VLBWIs and of infants with GA 22–23, 24–25, 26–27, 28–29, 30–32, and > 32 weeks were 86% (total), 33%, 65%, 84%, 94%, 97%, and 98%, respectively. The bronchopulmonary dysplasia (BPD) rates of all VLBWIs and of infants with GA 22–23, 24–25, 26–27, 28–29, 30–32, and > 32 weeks were 30% (total), 88%, 64%, 47%, 26%, 14%, and 5%, respectively. The intraventricular hemorrhage rates (≥ grade III) of all VLBWIs and of infants with GA 22–23, 24–25, 26–27, 28–29, 30–32, and > 32 weeks were 10% (total), 45%, 27%, 12%, 5%, 2%, and 1%, respectively. In an international comparison, the survival rate of VLBWIs with GA 24–27 weeks in KNN was lower, and the BPD rate of VLBWIs in the KNN was higher than that of the neonatal networks of other countries. CONCLUSION: Despite overall improvements in neonatal outcomes, the survival and morbidity rates of more immature infants with GA 22–27 weeks need further improvement. Therefore, it would be necessary to develop more optimal treatment strategies and perform more active quality improvement to further improve neonatal outcomes of VLBWIs in Korea.
Bronchopulmonary Dysplasia ; Gestational Age ; Hemorrhage ; Humans ; Infant Mortality ; Infant ; Infant, Newborn ; Infant, Premature ; Infant, Very Low Birth Weight ; Intensive Care Units, Neonatal ; Korea ; Quality Improvement ; Survival Rate

PURPOSE: The purpose of this study was to investigate the outcome after changes in the treatment strategies for very low birth weight infant (VLBWI) in a single neonatal intensive care unit (NICU) center. METHODS: We performed a retrospective review of 300 VLBWI born from 1st January 2010 to 31th December 2016. We compared the outcomes including survival rate, birth weight (BW), gestational age (GA), and morbidities between period I (2010–2013, P-I) and period II (2014–2016, P-II). RESULTS: The average survival rate was not different between P-I and P-II. However, the survival rate of ≤24 weeks' GA, 25 weeks' GA, 26 weeks' GA were 57%, 69%, 93% respectively in P-II and 31%, 59%, 87% in P-I respectively. The survival rate of infants with birth weight <500 g, 500–749 g, 750–999 g were 100%, 55%, 90% respectively in P-II and 50%, 24%, 80%, respectively in P-I. The incidence of bronchopulmonary dysplasia (BPD) was higher in P-II than in P-I (P=0.012) and moderate-to-severe BPD was also higher in P-II (P=0.004). Incidence of patent ductus arteriosus (PDA) with treatment, necrotizing enterocolitis (stage≥2), and abnormal brain sonography were significantly lower in P-II (P=0.027, P=0.032, P=0.005). Incidences of retinopathy of prematurity (ROP) with laser treatment and early sepsis were not different. CONCLUSION: The survival rate and complications of VLBWI were improved in period II, especially in less than 750 g and below 26 weeks, except incidence of BPD. Changes of NICU strategies were effective to improve mortality and morbidity in VLBWI.
Birth Weight ; Brain ; Bronchopulmonary Dysplasia ; Ductus Arteriosus, Patent ; Enterocolitis, Necrotizing ; Gestational Age ; Humans ; Incidence ; Infant ; Infant, Newborn ; Infant, Very Low Birth Weight ; Intensive Care Units ; Intensive Care, Neonatal ; Mortality ; Retinopathy of Prematurity ; Retrospective Studies ; Sepsis ; Survival Rate

PURPOSE: This study investigated predictive factors for severe neonatal thrombocytopenia, which greatly increases the need for intensive care and is associated with a high mortality rate in premature infants. Factors adopted for prompt identification of at-risk newborns include blood test results and birth history. This study analyzed the relationship between the presence of severe neonatal thrombocytopenia and the mortality rate. The causes of thrombocytopenia in premature infants were also examined. METHODS: This retrospective study evaluated 625 premature infants admitted to the neonatal intensive care unit (NICU) at Chung-Ang University Medical Center. The neonates were classified into 3 groups according to the severity of thrombocytopenia: mild (100×10⁹/L≤platelet < 150×10⁹/L), moderate (50×10⁹/L≤platelet < 100×10⁹/L), or severe (platelet < 50×10⁹/L). Analysis of blood samples obtained at the onset of thrombocytopenia included platelet count, white blood cell (WBC) count, hemoglobin level, hematocrit level, absolute neutrophil count, and high-sensitivity C-reactive protein level. RESULTS: Of the 625 premature infants admitted to our NICU, 214 were detected with thrombocytopenia. The mortality rate in thrombocytopenic neonates was 18.2% (39/214), whereas a mortality rate of only 1.0% was observed in non-thrombocytopenic neonates. The major causes of thrombocytopenia were perinatal insufficiency and sepsis in premature infants. Severe thrombocytopenia was noted more frequently in premature infants with higher WBC counts and in those with a younger gestational age. CONCLUSION: Platelet count, WBC count, and gestational age are reliable predictors for severe neonatal thrombocytopenia. The major causes of thrombocytopenia were perinatal insufficiency and sepsis in premature infants.
Academic Medical Centers ; C-Reactive Protein ; Classification ; Critical Care ; Gestational Age ; Hematocrit ; Hematologic Tests ; Humans ; Infant, Newborn ; Infant, Premature ; Intensive Care, Neonatal ; Leukocytes ; Mortality ; Neutrophils ; Platelet Count ; Reproductive History ; Retrospective Studies ; Sepsis ; Thrombocytopenia ; Thrombocytopenia, Neonatal Alloimmune

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.
Birth Weight ; Body Temperature ; Delivery Rooms ; Fever ; Gestational Age ; Hemorrhage ; Humans ; Hypothermia* ; Incidence ; Infant ; Infant, Newborn ; Infant, Premature* ; Infant, Very Low Birth Weight ; Intensive Care, Neonatal ; Mortality ; Qi ; Quality Improvement*

BACKGROUND: Although the number of high-risk neonates has increased in Korea, hospitals were reluctant to open or maintain neonatal intensive care unit (NICU) due to the low medical cost. Consequently, there were regional disparities in facilities, equipment, and neonatal health outcomes. For these reasons, the Korean government began to invest in neonatal care during the last decade. We identified the status of NICUs in Korea and assessed changes after the government-driven policies. METHODS: We surveyed 87 of 89 hospitals that operated NICUs in 2015. The questionnaire assessed the number of NICU beds, admission and mortality rates of very low birthweight infants (VLBWIs), personnel status, equipment and facilities, and available multidisciplinary approach. Current data was compared with the previous studies and changes in the status and function of the nationwide NICU from 2009 and 2011. RESULTS: During the last 7 years, there was an increase of 462 NICU beds, which met the required number estimated by the number of births and covered about 90% of regional VLBWI births. Status of facilities and equipment improved in all regions in Korea but there were still regional differences in multidisciplinary approach and human resources. The difference in odds ratios for mortality of VLBWI between regions decreased compared to 2009. CONCLUSION: There was improvement in regional disparities of neonatal care and mortality of premature babies with the government investment in Korea. Further supports are required for human resources and referral system.
Humans ; Infant ; Infant Health ; Infant, Newborn ; Intensive Care, Neonatal ; Investments ; Korea ; Mortality ; Odds Ratio ; Parturition ; Referral and Consultation