Determinants of morbidity in late preterm infants

Objective

To assess the effect of selected maternal medical conditions and complications of pregnancy on the risk for morbidity among late preterm neonates.

Design

Prospective cohort study.

Material and methods

A total of 548 late preterm neonates (34^0/7 to 36^6/7 weeks' gestation) delivered from August 2006 to July 2009, were included. Information regarding demographics, gestational age, mode of delivery, maternal age and parity, pre-existing medical conditions and complications of pregnancy were obtained and associated with neonatal morbidity, both independently and as joint exposures. Newborn morbidity was defined by combining specific diagnoses, length of hospital stay, and transfer to the Neonatal Intensive Care Unit.

Results

Overall, 165 (30.1%) of the late preterm infants suffered from morbidity. The morbidity rates were 16.8% at 36 weeks' gestation, and then approximately doubled from 38.2% at 35 weeks to 59.7% at 34 weeks. The joint effect of gestational age (OR 8.43 for 34 weeks and 3.60 for 35 weeks' gestation), small for gestational age (SGA) (OR 4.18), multiple gestation (OR 3.68) and lack of antenatal steroid administration (OR 4.03), was greater than the independent effect of each of these factors, and greater than additive. Emergency caesarean section (OR 1.43) and antepartum haemorrhage (OR 3.07) were also associated with a significant impact on neonatal morbidity.

Conclusions

The risk for morbidity among late preterm infants, changes with each passing week of gestation. This risk seems to be intensified, when other exposures such as SGA, multiple gestation, emergency caesarean section, lack of antenatal steroid administration and antepartum haemorrhage, are also present.     

Neonatal morbidity in singleton late preterm infants compared with full-term infants

Aim: The aim of this study was to test the hypothesis that singleton late preterm infants (34 0/7 to 36 6/7 weeks of gestation) compared with full‐term infants have a higher incidence of short‐term morbidity and stay longer in hospital. Methods: In this retrospective, multicentre study, electronic data of children born at five hospitals in Switzerland were recorded. Short‐term outcome of late preterm infants was compared with a control group of full‐term infants (39 0/7 to 40 6/7 weeks of gestation). Multiple gestations, pregnancies complicated by foetal malformations, maternal consumption of illicit drugs and infants with incomplete documentation were excluded. The results were corrected for gender imbalance. Results: Data from 530 late preterm and 1686 full‐term infants were analysed. Compared with full‐term infants, late preterm infants had a significant higher morbidity: respiratory distress (34.7% vs. 4.6%), hyperbilirubinaemia (47.7% vs. 3.4%), hypoglycaemia (14.3% vs. 0.6%), hypothermia (2.5% vs. 0.6%) and duration of hospitalization (mean, 9.9 days vs. 5.2 days). The risk to develop at least one complication was 7.6 (95% CI: 6.2–9.6) times higher among late preterm infants (70.8%) than among full‐term infants (9.3%). Conclusion: Singleton late preterm infants show considerably higher rate of medical complications and prolonged hospital stay compared with matched full‐term infants and therefore need more medical and financial resources.     

Early childhood health and morbidity,including respiratory function in late preterm and early term births

Late preterm (LP) and early term (ET) infants have generally been considered in the same way as their healthy full term (FT) counterparts. It is only in the last decade that an increased risk of later poor health in children born LP has been recognised; evidence for health outcomes following ET birth is still emerging. However, reports are largely consistent in highlighting an increased risk, which lessens approaching FT but is measurable and persists into adolescence and beyond. The most thoroughly explored area to date is respiratory morbidity. This article reviews the body of available evidence for effects of LP birth on pulmonary function and ongoing morbidity, and other areas where an increased risk of health problems has been identified in this population. Implications for delivery of health care are considered and areas for further research are highlighted.     

Epidemiology of preterm birth and neonatal outcome

In industrialized countries, 5–11% of infants are born preterm (<37 weeks' gestation), and the rate has been increasing since the early 1980s. Preterm births account for 70% of neonatal deaths and up to 75% of neonatal morbidity, and contribute to long-term neurocognitive deficits, pulmonary dysfunction and ophthalmologic disorders. In the past several decades, major progress has been made in improving the survival of extremely premature newborns, mostly attributable to timely access to effective interventions that ameliorate prematurity-associated mortality and morbidity such as antenatal administration of corticosteroids and exogenous surfactant therapy, rather than preventing preterm births. However, the societal and healthcare costs to care for survivors with severe morbidity and neurological handicaps remain substantial. Future research should concentrate on the ways to reduce long-term health sequelae and developmental handicaps among survivors of infants born preterm, as well as elucidating the mechanisms and aetiology of preterm births.     

晚期早产儿低氧性呼吸衰竭的病死率及其影响因素分析

目的 探讨山东省中东部地区晚期早产儿低氧性呼吸衰竭病例的分布情况及其病死率的的影响因素,为提高晚期早产儿呼吸衰竭临床诊治水平提供理论依据,为今后山东全省乃至全国的相关研究提供参考依据.方法 采用整群抽样的原则选取山东省中东部地区7所医院内NICU自2010年1月1日至2012年12月31日收治的,诊断为呼吸衰竭的晚期早产儿216例.分析患儿的基本资料、原发疾病、临床诊疗方法、结局、病死率及影响因素.结果 （1）共收回调查问卷216份,男女比例为1.3∶1,发生呼吸衰竭的病因各地区不尽相同.（2）平均出生体重为（2660＆#177;686）g,最小体重1 900 g,最大体重3 600 g.合并先天畸形38例,其中6例合并2种以上畸形.先天畸形中,先天性心脏病（包括动脉导管未闭）16例.孕母年龄最小18岁,最大42岁,平均32岁;分娩方式中经阴顺产和剖宫产例数相当,分别为110例和106例.孕母产前应用糖皮质激素促进胎肺成熟137例.（3）患儿主要原发疾病为呼吸窘迫综合征112例、肺部感染和败血症52例.常见并发症主要为肺部感染、败血症23例,动脉导管未闭89例,重要脏器出血7例.（4）不同胎龄呼吸衰竭晚期早产儿病死率总体上差异有统计学意义（χ2 =157.148,P=0.000）,胎龄越小,病死率越高.（5）影响病死率的因素中,合并先天畸形[OR=2.063,95％CI （1.297,3.264）]、低出生体重[OR=4.335,95％CI（1.636,11.497）]、重要脏器出血[OR =4.598,95％ CI（1.370,14.925）]、单用常频机械通气[OR =0.531,95％CI（0.314,0.902）]的呼吸衰竭晚期早产儿死亡风险高.结论 目前山东省中东部地区因各种疾病导致的呼吸衰竭发生率较低,原发疾病主要为呼吸窘迫综合征、肺部感染和重度室息.晚期早产儿呼吸衰竭治疗时间更长,多种治疗手段的应用显著改善患儿预后.     

287例晚期早产儿早产危险因素及并发症研究

目的：探讨晚期早产儿(late preterm infant, LPI) 早产相关危险因素及临床常见并发症。方法：对287例LPI临床资料进行回顾性分析,同时随机抽取288例同期住院的足月新生儿作对照,应用logistic回归分析的方法筛选LPI早产的危险因素,并分析其常见临床并发症的发生等情况。结果：Logistic回归显示双胎、妊娠期糖尿病、先兆子癎及子癎、前置胎盘、胎盘早剥及胎膜早破为LPI早产发生的危险因素。LPI住院时间明显长于足月儿,其各系统并发症发生率均较高,其中以贫血、吸入性肺炎、低血糖症、颅内出血等为主。结论：LPI生后易发生多种并发症,应注意密切观察,及时救治。避免围产期异常分娩因素的发生是降低LPI出生的关键。     

妇女孕前体重指数对晚期早产儿不良结局的影响

目的探讨妇女孕前体重指数(BMI)与晚期早产儿(LPI)不良结局的关系。方法选择2011年1月至2015年12月的367例住院LPI为研究对象。分析母亲孕前BMI水平的相关因素,以及与LPI不良结局(1 min Apgar评分≤7分、产房复苏、住院天数7 d以及呼吸机通气时间≥6 h)的关系。结果母亲孕前BMI降低、正常、增高的分别有64例(17.4%)、243例(66.2%)以及60例(16.4%)。母亲孕前BMI降低是LPI 1 min Apgar评分≤7分(OR=3.243,95%CI:1.102~9.546)和需要产房复苏(OR=3.492,95%CI:1.090~11.190)的危险因素,孕前高BMI是LPI住院时间7 d(OR=1.992,95%CI:1.024~3.874)的危险因素。结论妇女孕前BMI对LPI结局产生影响,建议妇女孕前控制BMI水平在正常范围内,减少LPI不良结局发生。     

Spanish population‐study shows that healthy late preterm infants had worse outcomes one year after discharge than term‐born infants

Aim

This study assessed the risks associated with healthy late preterm infants and healthy term‐born infants using national hospital discharge records.

Method

We used the minimum basic data set of the Spanish hospital discharge records database for 2012–2013 to analyse the hospitalisation of newborn infants. The outcomes were in‐hospital mortality and hospital re‐admissions at 30 days and one year after their first discharge.

Results

Of the 95 011 newborn infants who were discharged, 2940 were healthy late preterm infants, born at 34 + 0–36 + 6 weeks, and 18 197 were healthy term‐born infants. The mean and standard deviation (SD) length of hospital stay were 6.0 (4.5) days in late preterm infants versus 2.8 (1.3) days in term‐born infants (p < 0.001). Re‐admissions were also higher in the late preterm group at 30 days (9.0% versus 4.4%) and one year (22.0% versus 12.4) (p < 0.001). The relative risk for death at one year was 4.9 in the late preterm group, when compared to the term‐born infants (p = 0.026).

Conclusion

The hospital discharge codes for otherwise healthy newborn preterm infants were associated with significantly worse 30‐day and one‐year outcomes when their re‐admission and mortality rates were compared with healthy term‐born newborn infants.     

Diabetic mothers and their newborn infants – rooming‐in and neonatal morbidity

Aim: As a result of increased neonatal morbidity, the infants of diabetic mothers have routinely been admitted to a neonatal special care unit (NSCU). We therefore investigated whether the offer of rooming‐in diabetic mothers and their newborn infants has an effect on neonatal morbidity. Methods: The records of an old cohort of 103 infants routinely admitted to the NSCU, and a new cohort (N = 102), offered rooming‐in were assessed for neonatal morbidity. Results: Eighty‐four (82%) of the new cohort infants followed their mothers to the maternity ward; whereas 19 (18%) were transferred to the NSCU chiefly because of prematurity. Ten infants were later transferred to the NSCU for minor problems. Neonatal morbidity and neonatal hypoglycaemia were significantly less common in the new cohort than in the old cohort [27 (26%) vs. 55 (54%), p < 0.001 and 42 (41%) vs. 64 (63%), p = 0.0027 respectively]. Maternal HbA1c in late pregnancy was significantly lower in the new cohort, but the only independent predictors of neonatal morbidity were belonging to the old cohort and preterm delivery. Conclusion: Neonatal care with rooming‐in mothers with type 1 diabetes and their newborn infants seems safe and is associated with reduced neonatal morbidity, when compared with routine separation of infants from their mothers.     

Changes in care and short-term outcome for very preterm infants in Estonia

Aim: To identify recent changes in short‐term outcome and care for very preterm infants in Estonia. Methods: Comparison of two population‐based cohorts of very preterm infants born alive at 22–31 gestational weeks. In 2007–2008, data were recorded prospectively in a neonatal register. For the cohort born in 2002–2003, the same variables were extracted retrospectively from the hospital records. Infants were followed up to discharge or death. Results: The cohort of 2007−2008 contained a higher proportion of infants born by caesarean section and of infants who received antenatal corticosteroids, maternal antibiotics, or surfactant therapy than the earlier cohort. A higher proportion of infants was admitted for care in 2007–2008 (98% vs. 94%; p = 0.013). During the study period, survival until discharge increased (85% vs. 78%; p = 0.041), although the length of hospital stay was unchanged. The use of mechanical ventilation, inotropes, and postnatal antibiotics decreased. Neonatal morbidity remained unchanged, except for a decrease in severe periventricular/intraventricular hemorrhage. Conclusion: The outcome for very preterm infants in Estonia has improved since 2002. With proactive perinatal management and less invasive neonatal care, survival until discharge increased without concomitant increases in neonatal morbidity and the length of hospital stay.     

超早产儿出生时间与复苏结局的关系

目的 探讨非工作时间(工作日夜间6 pm～8 am、周末和国家法定节假日)出生的与正常工作时间出生的超早产儿复苏过程和早期结局有无差异.方法 回顾性收集2010年1月1日至2020年12月31日于北京大学第三医院出生并转入新生儿重症监护病房的超早产儿病例.根据出生时间的不同分为工作时间出生组(n=77)和非工作时间出生...     

Predicting developmental outcomes in very preterm infants: validity of a neonatal neurobehavioral assessment

Aim: This study explored inter‐rater reliability, discriminative, construct and predictive validity of the Neurobehavioral Assessment of the Preterm Infant (NAPI) in a gestational‐age‐based cohort. Methods: The NAPI was conducted at 35 weeks post‐menstrual age for 170 infants born <32 weeks. Cognitive and motor development was assessed at 2 years using the Mental Development Index (MDI) and Psychomotor Development Index (PDI) of Bayley Scales of Infant Development‐II for 159 infants. Results: Only NAPI motor and irritability scores were significantly different between very (29–3 w) and extremely preterm (<28 w) infants. Results regarding construct validity were variable: there were weak correlations between NAPI motor scores and gestational age (r = ?0.23; p = 0.003), days in NICU (r = ?0.24; p = 0.001); NAPI alertness scores and days in NICU (r = ?0.16; p = 0.037); and NAPI irritability scores and gestational age (r = 0.21; p = 0.006). There were no significant associations with other markers of adverse outcome. Only NAPI irritability scores were correlated with MDI scores (r = ?0.16; p = 0.040) but accounted for little additional variance after adjustment for neonatal factors (ΔR² = 0.035; p = 0.012). Conclusion: We found little evidence of the utility of the NAPI as a measure of short‐term neurobehavioural function or for predicting neurodevelopmental outcomes in very preterm infants. It may have greater predictive power when used serially to detect delayed neurobehavioural maturation.     

高危晚期早产儿脑病临床特点及磁共振影像学评估

目的了解高危晚期早产儿(LPI)脑病的危险因素、临床特点及磁共振(MRI)影像学变化。方法对2009年1月至2014年12月住院且存在脑损伤高危因素的LPI,进行头颅MRI检查,分析LPI脑病危险因素、临床特点及头颅MRI特征。结果完成MRI检查的LPI共1 007例,影像学符合早产儿脑病患儿313例(31.1%)。LPI脑病中白质损伤占76.7%。LPI脑病的发生与胎龄无相关性,但随着出生体重增加,脑病检出率逐渐增高(P0.05)。Logistic回归分析结果显示:复苏史是早产儿脑病发生的独立危险因素(P0.01)。结论早产儿脑病在高危LPI中亦较常见,特别是脑白质损伤。复苏病史是LPI脑病的独立危险因素,需引起重视。