Histologic chorioamnionitis and severity of illness in very low birth weight newborns.

OBJECTIVE: Estimating the risk of in-hospital mortality in the neonatal intensive care unit provides important information for health care providers, and several neonatal illness severity scores have been developed. Histologic chorioamnionitis (HCA) is a known cause of neonatal morbidity and mortality. To date, the relationship between HCA and neonatal illness severity scores has not been rigorously tested. In this study, the relationships among HCA, initial illness severity, and neonatal outcomes were analyzed in very low birth weight (VLBW) newborns admitted to the neonatal intensive care unit. DESIGN: Prospective. SETTING: Neonatal intensive care unit. PATIENTS: A total of 116 VLBW inborn infants (gestational age, 28.1 +/- 2.82 wks; birth weight, 1009 +/- 312 g) were categorized as HCA-positive (n = 67) and HCA-negative (n = 49). INTERVENTIONS: Placental histology was performed to identify HCA. Illness severity evaluation included several different neonatal illness severity scores-Clinical Risk Index for Babies (CRIB), CRIB-II, Score for Neonatal Acute Physiology-II (SNAP-II), and Score for Neonatal Acute Physiology Perinatal Extension-II (SNAPPE-II)-as well as the recording of severe morbidity and in-hospital mortality. MEASUREMENTS AND MAIN RESULTS: HCA-positive VLBW newborns showed significantly lower gestational age (p < .0001) and birth weight (p = .0010), together with higher CRIB, CRIB-II, SNAP-II, and SNAPPE-II scores at admission to the NICU (p 5 (odds ratio [OR], 21.37; 95% confidence interval [CI], 6.24-73.21); CRIB-II > 10 (OR, 56.17; 95% CI, 6.75-467.2); SNAP-II > 22 (OR, 43.05; 95% CI, 11.9-155.7), and SNAPPE-II > 42 (OR, 48.95; 95% CI, 10.18-235.4) (all p values <.0001). CONCLUSIONS: Our findings indicate that HCA is a major predictor of morbidity and mortality in VLBW newborns.     

Severe retinopathy of prematurity and its association with different rates of survival in infants of less than 1251 g birth weight

BACKGROUND: There is controversy over whether improved survival of preterm infants has resulted in a higher incidence of severe (grade 3 or greater) retinopathy of prematurity (ROP). AIM: To compare survival rates and rates of > or = stage 3 ROP-that is, with a high risk of sequelae-in preterm infants in five English cities where, anecdotally, the incidence of ROP is reported to show considerable variation. METHODS: All infants of birth weight < 1500 g and or gestational age < 32 weeks, born in 1994 in one of the cities or transferred in within 48 hours, were studied. The populations were adjusted for case mix variation using CRIB (clinical risk index for babies, a disease severity scoring system). The incidence of severe ROP, the actual death rate, and that adjusted for disease severity were determined. RESULTS: The rate of severe ROP per 1000 births was higher in city 1 than in all the other cities. This increase in comparison with city 2 and city 4 was significant (city 1, 167 (95% confidence interval (CI) 96 to 260); city 2, 24 (6 to 59); city 4, 16 (1 to 84)). A significant difference was not seen between city 1 and cities 3 (23 (1 to 120)) and 5 (74 (21 to 79)). The relative risk of developing severe ROP in city 1 compared with all the other cities was 5.5 (2.5 to 11.9). The actual death rate per 1000 births in city 1 was significantly lower than that predicted by modelling death against CRIB score (city 1: actual 270; predicted 385 (95% CI 339 to 431)). In contrast, the other cities had actual death rates as predicted, or worse than predicted, by CRIB. INTERPRETATION: A significantly higher incidence of severe ROP was identified in one of the five cities studied. Variation in survival rates among high risk infants may explain this observation.     

CRIB,CRIB‐II,birth weight or gestational age to assess mortality risk in very low birth weight infants?

AIM: The mortality risk of very low birth weight (VLBW) (<1500 g) infants has been estimated by the Clinical Risk Index for Babies (CRIB). Superior discriminatory power has been claimed for the revised CRIB-II score based on birth weight, gestational age, sex, temperature and base excess (BE) at admission. This analysis compared the power of CRIB, CRIB-II, birth weight and gestational age to predict death prior to discharge. METHODS: Of 1485 consecutive VLBW infants admitted between January 1, 1991 and December 31, 2006, who survived for >or=12 h, CRIB and CRIB-II calculations were possible in 1358 infants (92%). Predictive power of variables was assessed by comparing areas under receiver operator characteristics curves (AUC). RESULTS: CRIB (AUC [95% confidence intervals] 0.82 [0.78-0.86]) performed significantly better than birth weight (0.74 [0.69-0.79]) or gestational age (0.71 [0.66-0.76]), while CRIB-II (0.69 [0.64-0.74]) was rather inferior to CRIB and did not differ significantly from birth weight or gestational age. No substantial changes were seen when substituting worst BE during the first 12 h of life for BE at admission when calculating CRIB-II. CONCLUSIONS: CRIB-II does not result in improved estimation of mortality risk in VLBW infants as compared to CRIB, birth weight or gestational age.     

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目的 探讨极低出生体重儿(VLBWI)脑室周围-脑室内出血(PVH-IVH)的高危因素。方法 回顾性对照分析2009年10月至2010年11月青岛大学医学院附属医院VLBWI117例病例,PVH-IVH39例为PVH-IVH组,按胎龄、出生体重1∶2配对的无PVH-IVH78例为对照组,对其相关因素采用SAS9.0软件进行配对条件Logistic回归分析。结果 130例VLBWI中发生PVH-IVH39例,发生率为30.00%。应用1∶2配对的条件Logistic回归分析示经阴分娩(OR=1461.699,CI7.216～296094.700,P<0.0001)、胎儿宫内窘迫(OR=95.172,CI2.213～4093.612,P=0.0006)、机械通气(OR=65.124,CI2.258～1878.432,P=0.0228)、动脉导管未闭(PDA)(OR=42.051,CI1.935～913.839,P=0.0283)、低钠血症(OR=33.415,CI0.936～1192.593,P=0.0475)、低钙血症(OR=25.175,CI1.328～477.243,P=0.0325)是VLBWI发生PVH-IVH的高危因素;产前使用激素(OR=0.061,CI0.004～0.884,P=0.0017)是避免患儿发生PVH-IVH的保护因素。结论 经阴分娩、胎儿宫内窘迫、机械通气、PDA及电解质紊乱是VLBWI发生PVH-IVH的高危因素,而产前使用激素可预防PVH-IVH的发生,因此PVH-IVH的发生是多种因素相互作用的复杂结果。在围生期工作中应当高度重视这些因素,以提高早产儿的生存质量。     

Assessing mortality risk in very low birthweight infants: a comparison of CRIB, CRIB-II, and SNAPPE-II

BACKGROUND: Illness severity scores are increasingly used for risk adjustment in clinical research and quality assessment. Recently, a simplified version of the score for neonatal acute physiology (SNAPPE-II) and a revised clinical risk index for babies (CRIB-II) score have been published. AIM: To compare the discriminatory ability and goodness of fit of CRIB, CRIB-II, and SNAPPE-II in a cohort of neonates < 1500 g birth weight (VLBWI). METHODS: Data from 720 VLBWI, admitted to 12 neonatal units in Lombardy (Northern Italy) participating in a regional network, were analysed. The discriminatory ability of the scores was assessed measuring the area under the receiver operating characteristic curve (AUC). Outcome measure was in-hospital death. RESULTS: CRIB and CRIB-II showed greater discrimination than SNAPPE-II (AUC 0.90 and 0.91 v 0.84, p < 0.0004), partly because of the poor quality of some of the data required for the SNAPPE-II calculation-for example, urine output-but also because of the relative weight given to some items. In addition to each score, several variables significantly influenced survival in logistic regression models. Antenatal steroid prophylaxis, singleton birth, absence of congenital anomalies, and gestational age were independent predictors of survival for all scores, in addition to caesarean section and not being small for gestation (for SNAPPE-II) and a five minute Apgar score of > or = 7 (for SNAPPE-II and CRIB). CONCLUSIONS: CRIB and CRIB-II had greater discriminatory ability than SNAPPE-II. Risk adjustment using all scores is imperfect, and other perinatal factors significantly influence VLBWI survival. CRIB-II seems to be less confounded by these factors.     

需要机械通气的极低出生体重儿院内病死率及病死风险因素的前瞻性研究

目的：描述危重极低出生体重儿（VLBWI）的临床特征、接受治疗状况及其转归,评估其病死风险相关因素,评价CRIB、SNAPPE-II评分系统预测我国早产儿病死风险的价值。方法：对2010年1月至2011年10月间新生儿重症监护室（NICU）收治的127例需要机械通气的VLBWI进行前瞻性数据收集。结果：纳入患儿平均胎龄为31±2 周,平均体重为1290±170 g,男女比例为1.23∶1,超低出生体重儿占6.3%。接受肺表面活性剂（PS）治疗者占 48.0%;接受气管插管机械通气的患儿占49.6%。总的院内病死率为41.7%。低出生体重、多胎分娩、剖宫产、低PaO2/FiO2比值是病死的独立风险因素,OR值分别为1.611、7.572、4.062、0.133,P<0.05。SNAPPE-II和CRIB评分系统可较好地预测病死转归,ROC曲线下面积分别为0.806、0.777。结论：VLBWI总的病死率仍处于较高水平;低出生体重、多胎分娩、剖宫产、低PaO2/FiO2比值是VLBWI病死的高危因素。应用新生儿危重评分系统可对研究对象疾病危重程度进行量化。     

Short-term outcome after active perinatal management at 23-25 weeks of gestation. A study from two Swedish perinatal centres. Part 3: neonatal morbidity

Aim: To determine major neonatal morbidity in surviving infants born at 23-25 weeks, and to identify maternal and infant factors associated with major morbidity. Methods: The medical records of 224 infants who were delivered at two tertiary care centres in 1992-1998 were reviewed retrospectively. At these centres, policies of active perinatal and neonatal management were universally applied. Of the 213 liveborn infants, 140 (66%) survived to discharge. Data were analysed by gestational age and considered in three time periods. Logistic regression models were used to identify factors associated with morbidity. Results: Of the survivors, 6% had intraventricular haemorrhage grade ≥3 (severe IVH) or periventricular leukomalacia (PVL), 15% retinopathy of prematurity ≥stage 3 (severe ROP) and 36% bronchopulmonary dysplasia (BPD). On logistic regression analysis, severe IVH or PVL was associated with duration of mechanical ventilation (odds ratio, OR: 1.53 per 1-wk increment in duration; 95% confidence interval, CI: 1.01-2.33). Severe ROP was associated with the presence of a patent ductus arteriosus (PDA) (OR: 3.31; 95% CI: 1.11-9.90) and birth in time period 3 versus time periods 1 and 2 combined (OR: 6.28; 95% CI: 2.10-18.74). BPD was associated with duration of mechanical ventilation (OR: 2.71 per 1-wk increment in duration; 95% CI: 1.76-4.18) and with the presence of any obstetric complication (OR: 2.67; 95% CI: 1.07-6.65). Gestational age and birthweight were not associated with major morbidity. Of all survivors, 81% were discharged home without severe IVH, PVL or severe ROP.

Conclusions: Increased survival as a result of active perinatal and neonatal management was associated with favourable morbidity rates compared with those in recent studies. Among survivors born at 23-25 weeks, neither gestational age nor birthweight was a significant determinant of major morbidity.     

Trends in outcomes for very preterm infants in the southern region of Sweden over a 10-year period

Aim: To investigate trends in mortality and morbidity in very preterm infants.
Methods: Population-based perinatal register; liveborn infants 22 + 0 to 31 + 6 gestational weeks were investigated (time period 1995–2004). Time trends for mortality and common morbidities were explored using logistic regression analyses.
Results: Data from 1614 liveborn infants were included. There was an increase in live born infants below 25 gestational weeks, annual odds ratio (OR) 1.15 (95% CI: 1.08–1.23) and a decrease in mortality annual OR 0.82 (95% CI: 0.69–0.98). The rates of bronchopulmonary dysplasia (BPD) and sepsis increased during the study period, annual ORs of 1.10 (95% CI: 1.04–1.17) and 1.09 (95% CI: 1.03–1.16). The duration of mechanical ventilation increased for surviving infants <25 gestational weeks (p = 0.003), while the duration of continuous positive airway pressure (CPAP) increased for infants <28 gestational weeks (p = <0.001). There were no changes in the rates of intraventricular haemorrhages (IVH, 3–4), retinopathy of prematurity (ROP, 3–5), seizures or necrotizing enterocolitis (NEC).
Conclusion: During the 10-year period changes in mortality and morbidity were most pronounced for infants with GA <28 gestational weeks. The increasing rate of sepsis was present in infants <28 gestational weeks, whereas the increase in BPD was demonstrated in the whole study population <32 gestational weeks.     

Comparison of different growth curves in the assessment of extrauterine growth restriction in very low birth weight preterm infants

BackgroundPreterm infants are at risk of extrauterine growth restriction (EUGR) and associated complications in the long term. Growth curves are important in assessing postnatal growth in these infants. The aim of this study was to determine the prevalence of EUGR in preterm infants and the factors associated with EUGR using two different growth curves.MethodsWe retrospectively evaluated 596 preterm infants with birth weight ≤1500 g. Small for gestational age (SGA) was defined as birth weight <10th percentile for gestational age. EUGR was defined as discharge weight z score <?2. All z scores were determined using both the Fenton 2013 and Intergrowth-21st (IG-21) growth curves.ResultsThe infants’ median gestational age was 28 weeks (27–29) and median birth weight was 1080 g (900–1243). The prevalence of SGA was 9.2% with IG-21 curves and 5% with Fenton curves (p < 0.001). The median discharge weight was 2060 g (1860–2363). The prevalence of EUGR was significantly higher with the Fenton curves than with the IG-21 curves (38% vs. 31.7%, p < 0.001). The mean discharge weight z score was ?1.82±1.29 with Fenton and ?1.44±1.49 with IG-21 curves. In multivariate analysis, significant risk factors for EUGR according to the Fenton curves were SGA (odds ratio [OR]: 19.15, 95% confidence interval [CI]: 4.4–82.59), respiratory distress syndrome (RDS) (OR 1.64, 95% CI 1.12–2.4), late neonatal sepsis (LNS) (OR: 2.27, 95% CI: 1.5–3.44), and >16 days to full enteral feeding (OR: 1.8, 95% CI: 1.22–2.68). Similarly, independent risk factors for EUGR according to the IG-21 curve were SGA (OR: 16.3, 95% CI: 7.23–36.9), RDS (OR: 1.81, 95% CI: 1.16–2.83), LNS (OR: 2.29, 95% CI: 1.43–3.68), and >16 days to full enteral feeding (OR: 2.11, 95% CI: 1.38–3.23).ConclusionThe growth curves used for diagnosis may lead to differences in EUGR rates in intensive care units and the factors identified as associated with EUGR. At-risk infants should be evaluated for EUGR and their weight and nutritional support should be monitored carefully. Comparisons of long-term outcomes are needed to assess the suitability of growth curves used for EUGR follow-up.     

Risk factors for intraventricular hemorrhage in very low birth weight infants in Tehran, Iran

Intraventricular hemorrhage (IVH) is an important cause of morbidity and mortality in very low birth weight (VLBW) infants; 80-90% of cases occur between birth and the third day of life. In a retrospective case control clinical study, files of all premature infants with birth weights <1500 grams admitted between April 2004 and October 2005 to the Neonatal Intensive Care Unit (NICU) of Akbar Abadi Hospital were reviewed. We determined risk factors that predispose to the development of high-grade IVH (grades 3 and 4) in VLBW infants. Thirty-nine infants with IVH grade 3 and 4 were identified. A control group of 82 VLBW infants were also selected. Prenatal data, delivery characteristics, neonatal course data and reports of cranial ultrasonography were carefully collected for both groups. Those variables that achieved significance (p<0.05) in univariate analysis were entered into multivariate logistic regression analysis. A total of 325 VLBW infants were evaluated. Mortality rate was 21.5%. Multivariate logistic analysis showed that the following factors are associated with greater risk of high-grade IVH occurrence: lower gestational age (OR: 3.72; 95% CI: 1.65-8.38), birth weight (OR: 3.42; 95% CI: 1.65-8.38), mechanical ventilation (OR: 4.14; 95% CI: 1.35-12.2), tocolytic therapy with magnesium sulfate (OR: 4.40; 95% CI: 1.10-24.5), hyaline membrane disease (HMD, OR: 3.16; 95% CI: 1.42-7.45), symptomatic hypotension (OR: 2.32; 95% CI: 1.06-5.42), hypercapnia (OR: 1.9; 95% CI: 1.1-3.4) and Apgar score at 5 minutes (OR: 1.58; 95% CI: 1.59-6.32).     

Factors associated with survival of very-low-birth-weight infants in a Brazilian fee-paying maternity in the 1990s

This study describes intra-hospital survival rates of very-low-birth-weight infants, as well as factors present at birth associated with survival, during a period of 10 years. This is a Retrospective cohort study performed in a 3rd level nursery at Santa Joana Maternity Hospital, a fee-paying institution in Sao Paulo, Brazil. From January 1991 to December 2000, 963 live-born infants with a birth weight of 500-1499 g, without congenital anomalies, were followed until discharge. Survival was studied according with year of birth, and stratified by birth weight and gestational age. Factors present at birth associated with survival were analyzed by logistic regression. Patient characteristics were: birth weight 500-999 g (38%), gestational ages or=750 g, and gestational age >or=26 weeks.     

胎龄≤32周早产儿低血糖的危险因素分析

目的 探讨胎龄≤32周早产儿出生后发生低血糖的危险因素。方法 回顾性纳入2017年1月至2020年6月入住新生儿重症监护病房的86例胎龄≤32周低血糖早产儿作为低血糖组,随机选取同期住院监测血糖正常的早产儿172例为对照组。采用单因素分析与多因素logistic回归分析筛选早产儿低血糖的危险因素。结果 研究期间早产儿共计515例,其中低血糖86例（16.7%）。低血糖组小于胎龄儿（SGA）、剖宫产出生、孕母高血压、产前使用激素的比例均高于对照组（P < 0.05）,而出生体重及血糖检测前已静脉使用葡萄糖的比例均低于对照组（P < 0.05）。SGA（OR=4.311,95% CI：1.285~14.462）、孕母高血压（OR=2.469,95% CI：1.310~4.652）和产前使用激素（OR=6.337,95% CI：1.430~28.095）为早产儿低血糖的危险因素（P < 0.05）,静脉使用葡萄糖（OR=0.318,95% CI：0.171~0.591）为早产儿低血糖的保护因素（P < 0.05）。结论 SGA、孕母高血压和产前使用激素可增加胎龄≤32周早产儿早期发生低血糖的风险;对胎龄≤32周早产儿,建议生后尽早静脉使用葡萄糖,以减少低血糖的发生。     

Italian multicentre study on retinopathy of prematurity

The aim of this prospective multicentre study was to evaluate the influence of a number of perinatal factors on the development of ROP in high risk preterm infants with gestational age ≤30 weeks. All infants consecutively born in, or transferred to, one of the 14 participating centres from 1 January 1992 through 31 December 1993, who had a gestational age of 30 weeks or less and no congenital anomalies and survived to the age of 6 months, were included in the study. Of the 380 infants with mean ± SD gestational age of 28.4 ± 1.6 weeks (range 23–30 weeks) and birth weight of 1157 ± 335 g (range 485–2480 g) that were eligible for the study, 82 (21.5%) developed ROP stage 1 or 2 and 57 (15%) ROP stage 3 or 3+. Step-wise logistic regression analysis showed that the following factors had a significant predictive value for the development of ROP stage 3 or 3+: gestational age (Odds Ratio (OR)=0.6144 for each increment of 1 week of gestational age), birth weight (OR=0.843 for each increment of 100 g of birth weight), prenatal steroids (OR 4.044 for lacking or incomplete prophylaxis), RDS (OR 2.294), oxygen dependency at 60 days (OR 2.085), necrotising enterocolitis (OR 2.597). Conclusion This study confirms the role of prematurity, low birth weight and RDS in the pathogenesis of ROP, and emphasises the importance of prenatal steroid prophylaxis of RDS in very preterm infants. Furthermore, our data suggest that infants with oxygen dependency at 60 days or necrotising enterocolitis are at very high risk of developing ROP. Received: 29 September 1996 and in revised form: 28 January 1997 / Accepted: 1 April 1997     

Predictors of extubation outcomes among extremely and very preterm infants: a retrospective cohort study

ObjectiveTo explore the clinical or sociodemographic predictors for both successful and failed extubation among Chinese extremely and very preterm infantsMethodsA retrospective cohort study was carried out among extremely and very preterm infants born at less than 32 weeks of gestational age (GA).ResultsCompared with the infants who experienced extubation failure, the successful infants had higher birth weight (OR 0.997; CI 0.996–0.998), higher GA (OR 0.582; 95% CI 0.499–0.678), a caesarean section delivery (OR 0.598; 95% CI 0.380–0.939), a higher five-minute Apgar score (OR 0.501; 95% CI 0.257–0.977), and a higher pH prior to extubation (OR 0.008; 95% CI 0.001–0.058). Failed extubation was associated with older mothers (OR 1.055; 95% CI 1.013–1.099), infants intubated in the delivery room (OR 2.820; 95% CI 1.742–4.563), a higher fraction of inspired oxygen (FiO₂) prior to extubation (OR 5.246; 95% CI 2.540–10.835), higher partial pressure of carbon dioxide (PCO₂) prior to extubation (OR 7.820; 95% CI 3.725–16.420), and higher amounts of lactic acid (OR 1.478;95% CI 1.063–2.056).ConclusionsHigher GA, higher pre-extubation pH, lower pre-extubation FiO₂ and PCO, and lower age at extubation are significant predictors of successful extubation among extremely and very preterm infants.     

Occurrence and severity of bronchopulmonary dysplasia and respiratory distress syndrome after a preterm birth

BACKGROUND:

Despite notable advances in neonatal care, bronchopulmonary dysplasia (BPD) remains an important complication of preterm birth, frequently resulting in prolonged hospital stay and long-term morbidity.

METHODS:

A historical cohort study of all preterm infants (gestational age younger than 37 weeks) admitted to the Montreal Children’s Hospital (Montreal, Quebec) between January 1, 1980, and December 31, 1992, was conducted. Information collected included demographic data, maternal and perinatal history, and main neonatal outcomes. Independent risk factors associated with BPD were identified by univariate analysis using one-way ANOVA, t tests or Mantel-Haenszel χ² testing. Severity of disease was studied using an ordinal multinomial logistic regression model.

RESULTS:

In total, 1192 preterm infants were admitted, of whom 551 developed respiratory distress syndrome and 322 developed BPD. For each additional week of prematurity, the risk of developing BPD increased by 54% (adjusted OR 1.54/week [95% CI 1.45 to 1.64]). For each point subtracted on the 1 min Apgar score, the risk of developing BPD was increased by 16% (OR 1.16 [95% CI 1.1 to 1.3]). BPD was also associated with the presence of patent ductus arteriosus (OR 3.5 [95% CI 2.1 to 6.0]), pneumothorax in the first 48 h (OR 9.4 [95% CI 3.6 to 24.8]) or neonatal pneumonia/sepsis in the neonatal period (OR 1.9 [95% CI 1.1 to 3.2]). Severity of BPD was associated with gestational age, 1 min Apgar score, very low birth weight and the presence of neonatal pneumonia/sepsis.

CONCLUSION:

Factors associated with BPD following a preterm birth were the degree of prematurity, birth weight, Apgar score at 1 min, and the presence of patent ductus arteriosus, pneumothorax or neonatal pneumonia/sepsis.     

Race, Candida sepsis, and retinopathy of prematurity

The objective of this observational cohort study at Georgetown University Hospital from January 1, 1994 through December 31, 1997 was to investigate race, Candida sepsis, and duration of oxygen exposure in infants with retinopathy of prematurity (ROP) with birth weight < or = 1,000 g. The incidence of ROP was 70.8% (114/161). The incidence of stage III or greater ROP in the Caucasian infants was significantly higher at 46.7% (14/30) than in the African-American infants at 23.8% (20/84) with p < 0.02. In addition, the incidence of threshold disease was higher in Caucasian infants 33.3% (10/30) when compared to African-American infants 9.5% (8/84) with p < 0.002. Using multiple logistic regression, African-American race was found to be an independent protective factor against developing severe ROP [adjusted odds ratio 0.39; 95% confidence interval (UCI) 0.16-0.97]. Extremely-low-birth-weight African-American infants with comparable severity of illness (including birth weight, gestational age, duration of supplemental oxygen exposure, and Candida sepsis) are less likely to develop severe ROP than Caucasian infants.     

Neurodevelopment and predictors of outcomes of children with birth weights of less than 1000 g: 1992-1995

OBJECTIVE: To examine the neurosensory and cognitive status of extremely low-birth-weight (ELBW; < 1,000 g) children born from January 1, 1992, through December 31, 1995, and to identify the significant predictors of outcome. DESIGN: An inception cohort of ELBW infants admitted to the neonatal intensive care unit (NICU) and observed to 20 months' corrected age. SETTING: A tertiary level urban NICU and follow-up clinic at a university hospital. POPULATION: Of 333 ELBW infants without major congenital malformations admitted to the NICU, 241 (72%) survived to 20 months' corrected age. We studied 221 children (92%) at a mean of 20 months' corrected age. The mean birth weight was 813 g; mean gestational age, 26.4 weeks. MAIN OUTCOME MEASURES: Assessments of cognitive and neurosensory development. RESULTS: Major neurosensory abnormality was present in 54 children (24%), including 33 (15%) with cerebral palsy, 20 (9%) with deafness, and 2 (1%) with blindness. The mean (+/- SD) Bayley-Mental Developmental Index (MDI) score was 74.7 +/- 17. Ninety-two children (42%) had a subnormal MDI score (<70). Neurodevelopmental impairment (neurosensory abnormality and/or MDI score <70) was present in 105 children (48%). Multiple stepwise logistic regression analysis that considered sex, social risk, birth weight, and neonatal risk factors revealed significant predictors of a subnormal MDI score to be male sex (odds ratio [OR], 2.73; 95% confidence interval [CI], 1.52-4.92), social risk (OR, 1.48; 95% CI, 1.09-2.00), and chronic lung disease (OR, 2.18; 95% CI, 1.20-3.94). Predictors of neurologic abnormality were a severely abnormal finding on cerebral ultrasound (OR, 8.09; 95% CI, 3.69-17.71) and chronic lung disease (OR, 2.46; 95% CI, 1.12-5.40); predictors of deafness were male sex (OR, 2.79; 95% CI, 1.02-7.62), sepsis (OR, 3.15; 95% CI, 1.05-9.48), and jaundice (maximal bilirubin level, >171 micromol/L [>10 mg/dL]) (OR, 4.80; 95% CI, 1.46-15.73). CONCLUSION: There is an urgent need for research into the etiology and prevention of neonatal morbidity.     

Association of genetic polymorphisms of vascular endothelial growth factor and risk for proliferative retinopathy of prematurity

The intention of our retrospective study was to determine whether vascular endothelial growth factor (VEGF) genetic polymorphisms are associated with risk for proliferative retinopathy of prematurity (ROP), a condition that is characterized by abnormal retinal neovascularization and can lead to retinal detachment and result in blindness. We enrolled 86 very low birth weight infants (birth weight < or =1500 g) who had been treated with cryo/laser therapy because of the risk for proliferative ROP (treated group). Their VEGF T-460C and G+405C genotypes were determined from dried blood samples and were compared with VEGF genotypes of 115 VLBW infants who were not treated with cryo/laser therapy (untreated group). We found that the allele frequency of VEGF +405C was higher in the treated group than in the untreated group (0.30 versus 0.41; p <0.05). The likelihood of being treated for ROP was higher in heterozygous and homozygous carriers of VEGF +405C alleles [odds ratios adjusted for risk factors of ROP (95% CI): 2.00 (1.02-3.92; p=0.04) and 3.37 (1.17-9.65; p=0.007), respectively]. VEGF -460TT/+405CC haplotype was more prevalent in the treated patients than in the untreated patients (13 of 86 versus 1 of 115; p <0.001), and the association remained significant (p <0.01) even after the adjustment for risk factors of ROP (gestational age, supplemental oxygen therapy, and gender). These findings suggest that the VEGF genotype may be associated with risk for proliferative ROP in VLBW infants.     

Human milk reduces the risk of retinal detachment in extremely low-birthweight infants

BACKGROUND: Retinopathy of prematurity (ROP) is a major cause of blindness in children. Because the use of oxygen is a known risk factor for development of ROP, supplemental oxygen is used carefully. However, it does not necessarily reduce the morbidity of ROP-induced blindness. The aim of the present study was to identify the possible risk factors for progression to retinal detachment, a most relevant cause of visual impairment, in extremely low-birthweight infants (ELBWI). METHODS: The medical records of the 42 ELBWI who were admitted to the neonatal intensive care unit in Asahikawa Kosei Hospital from April 1999 to March 2004 were retrospectively reviewed. Seven infants (16.7% of the ELBWI) developed retinal detachment and two of them became blind. Perinatal and postnatal variables in these infants with retinal detachment were compared with those in infants without retinal detachment. RESULTS: A striking difference in the daily intake of human milk was found between the infants with or without retinal detachment when their gestational ages at birth were matched. The infants without retinal detachment were fed more human milk (67-83% volume of total nutritional intake) as compared to those with retinal detachment (24-38% volume of total nutritional intake) at a specific postnatal period, 5-7 weeks postnatal age. CONCLUSIONS: Human milk may contain some beneficial factors to reduce the severity of ROP. Identifying these factors in human milk may contribute to development of a strategy to rescue premature infants from blindness.     

Respiratory distress syndrome in infants with impaired intrauterine growth

The recently introduced intrauterine growth curve, based on ultrasonically estimated foetal weights, was retrospectively applied to an inborn population of 883 infants bom before 33 gestational weeks at the University Hospital of Lund, during 1985–94. The estimation of birthweight deviation resulted in 630 (71.3%) infants with a birthweight appropriate for gestational age (AGA), 244 (27.6%) infants with a birthweight small for gestational age (SGA) and 9(1.1%) infants with a birthweight large for gestational age. Birthweight deviation was associated with an increased mortality [odds ratio (OR) adjusted for gestational age 1.29 per SD (12%) change in birthweight for gestational age, 95% CI: 1.10–1.50; p = 0.002]. At gestational age 25–28 weeks, SGA-infants had an increased incidence of respiratory distress syndrome (RDS) as compared to AGA-infants (OR adjusted for gestational age: 1.98,95% CI: 1.12–3.52; p = 0.019). At gestational age 29–32 weeks, SGA-infants had a lower incidence of RDS as compared to AGA-infants (OR adjusted for gestational age: OR 0.52,95% CI: 0.34–0.80; p = 0.003). After adjustment for confounding variables, infants born at gestational age 25–28 weeks from mothers with pre-eclampsia, appeared to be a high-risk group for RDS, whereas at the age of 29–32 gestational weeks, negative birthweight deviation had a protective effect against RDS. Antenatal corticosteroid administration appeared to have a less beneficial effect on mortality, RDS and cerebral haemorrhage in infants born SGA vs in those born AGA.