Predictors of Clinical Outcome in the Newborns of Persistent Pulmonary Hypertension Treated with Inhaled Nitric Oxide

PURPOSE: Inhaled nitric oxide (iNO) has been known to improve oxygenation in newborns with persistent pulmonary hypertension (PPHN). This study was performed to evaluate the predictors of clinical outcome in the newborn infants with PPHN treated with iNO. METHODS: Between September 1998 and August 2002, 23 newborn infants with PPHN treated with iNO were enrolled in this study. Reduction of oxygenation index (OI) and AaDO2 to 30% or more were defined as clinical response. Accoding to the response time within or after 12 hours, the clinical response was sub-categorized as early or delayed response, respectively. RESULTS: The mean gestational age and birth weight of 23 newborn infants were 36.7+/-4.4 weeks and 2,644+/-907 g. The mean baseline OI and AaDO2 were 22.20+/-13.63 and 477.16+/-127.96. There were ten non-responsders, eight early responsders and five delayed responders. Eleven neonates showed sustained response for 24 hours. The mean AaDO2, and PaO2 were decreased after 12 hours (P<0.05), while there was no difference in oxygenation index, arteral pH and PaCO2. The mortality rates of non-responders or not- sustained responders were higher than those of responders or sustained responders (P< 0.05). The birth weight of death group was lower than that of survival group and AaDO2, and OI at 12 hours after iNO therapy in survival group were lower than those in death group. CONCLUSION: Predictors of the clinical outcome of iNO therapy were clinical response patterns after iNO therapy, time taken until clinical response, duration of response and change of oxygenation at 12 hours after iNO therapy.

Predictors of Clinical Outcome in the Newborns of Persistent Pulmonary Hypertension Treated with Inhaled Nitric Oxide

PURPOSE: Inhaled nitric oxide (iNO) has been known to improve oxygenation in newborns with persistent pulmonary hypertension (PPHN). This study was performed to evaluate the predictors of clinical outcome in the newborn infants with PPHN treated with iNO. METHODS: Between September 1998 and August 2002, 23 newborn infants with PPHN treated with iNO were enrolled in this study. Reduction of oxygenation index (OI) and AaDO2 to 30% or more were defined as clinical response. Accoding to the response time within or after 12 hours, the clinical response was sub-categorized as early or delayed response, respectively. RESULTS: The mean gestational age and birth weight of 23 newborn infants were 36.7+/-4.4 weeks and 2,644+/-907 g. The mean baseline OI and AaDO2 were 22.20+/-13.63 and 477.16+/-127.96. There were ten non-responsders, eight early responsders and five delayed responders. Eleven neonates showed sustained response for 24 hours. The mean AaDO2, and PaO2 were decreased after 12 hours (P<0.05), while there was no difference in oxygenation index, arteral pH and PaCO2. The mortality rates of non-responders or not- sustained responders were higher than those of responders or sustained responders (P< 0.05). The birth weight of death group was lower than that of survival group and AaDO2, and OI at 12 hours after iNO therapy in survival group were lower than those in death group. CONCLUSION: Predictors of the clinical outcome of iNO therapy were clinical response patterns after iNO therapy, time taken until clinical response, duration of response and change of oxygenation at 12 hours after iNO therapy.

Statistical Study of Extremely Low Birth Weight (ELBW) Infants / 대한주산의학회잡지

PURPOSE: The purpose of our study was to review the perinatal clinical characteristics of extremely low birth weight(ELBW) infants and determine their risk factors of their deaths. METHODS: The medical records of 96 infants weighing less than 1,000g, who were born at Seoul National University Hospital and admitted to our neonatal intensive care unit(NICU) were analyzed retrospectively on the basis of clinical characteristics, obstetrical problems, postnatal complications and outcome. RESULTS: The annual birth rate of ELBW infants was 0.11% to 0.90% of total live births and the mean annual birth rate was 0.56% at Seoul National University Hospital. Preeclampsia was the most common obstetrical problem(34.4%), followed by incompetent internal os of cervix(IIOC) (13.5%), multiple pregnancy(13.5%) and in vitro fertilization(IVF)(13.5%). Respiratory distress syndrome(RDS) was the most common postnatal complication(78.1%), followed by sepsis(60.4%) and apnea(39.6%). Comparing the ELBW infants weighing less than 750g with those weighing more than 751g, sepsis was more frequent in the latter group(p<0.05), whereas high grade intraventricular hemorrhage(grade Ill) was more frequent in the former group(p<0.05). Otherwise there was no statistically significant difference concerning the frequency of perinatal complications between two groups. Comparing the ELBW infants born before the year 1991, when surfactant treatment started to be used routinely at our NICU, with those born after the year 1991, apnea and sepsis could be observed more frequent in the latter group(p<0.05). Otherwise there was no statistically significant difference in the frequency of perinatal complications between two groups, The survival rate of ELBW infants was 0.0% in 1986, 50.0% in 1991 and 40.0% in 1995. The risk factors of neonatal deaths of ELBW infants included birth weight, gestational period, mode of delivery, IIOC, RDS, apnea, pneumonia, pneumothorax, acute renal failure(ARF) and infections(except pneumonia), but analyzing these risk factors by multivariate logistic regression analysis, the resultant significant independent risk factors consisted only of birth weight, RDS and pneumonia(p<0.05). There was no statistically significant difference in survival rate between ELBW infants born before and after the year 1991, but there was a tendency toward increasing survival rates in the latter group. CONCLUSION: Recently, the survival rate of ELBW infants is improving steadily, but is still lower than that of western countries and postnatal morbidity remains high. Therefore, there is an urgent need to give more efforts to the neonatal intensive care of ELBW inFants in order to increase survival rates and reduce postnatal morbidity. But it is more important to reduce preterm birth by the treatment of preventable obstetrical risk factors.