Population-based trends in mortality and neonatal morbidities among singleton,very preterm,very low birth weight infants over 16 years

BackgroundImproved survival of singleton very preterm, very low birth weight (VPTVLBW) infants has been associated with increasing rates of severe neonatal morbidities.AimTo assess changes in mortality and neonatal morbidities among singleton VPT-VLBW infants.Study designPopulation-based observational study of data collected by the Israel Neonatal Network.Subjects10,705 singleton VPT-VLBW infants born at 24–32 gestational weeks in 1995–2010.Outcome measuresMortality and major neonatal morbidities over 3 time periods: 1995–2000, 2001–2005, and 2006–2010. Major neurological morbidities comprised intraventricular hemorrhage grades 3–4, periventricular leukomalacia and retinopathy of prematurity grades 3–4.ResultsThe mortality rate decreased over time from 20.2% to 13.8% for all birth weight and gestational age groups. Compared to the 1995–2000 period, the adjusted odds ratios (aORs) (95% confidence intervals,) for mortality in 2001–2005 and 2006–2010 were 0.78 (0.67–0.90) and 0.72 (0.62–0.84), respectively. The combined outcomes of death or major neurological morbidities, aOR 0.74 (0.65–0.84) and death or major neurological morbidities and/or bronchopulmonary dysplasia aOR 0.85 (0.75–0.96) decreased significantly between the first and last periods. A significant improvement in mortality rates and survival without one or more major neonatal morbidity was observed for all birth weight and gestational age groups.Among 8,886 surviving infants the rates of major neurological morbidities decreased from 16.4% to 12.8%, aOR 0.80 (0.68–0.95).ConclusionThe improving survival of singleton VTP-VLBW infants was not associated with a concomitant increase in the risk for major neonatal neurological morbidities among surviving infants. Bronchopulmonary dysplasia, however, remained a significant burden. This analysis emphasizes the need to direct efforts towards the prevention and treatment of adverse respiratory sequelae.     

Incidence of and risk factors for neonatal morbidity after active perinatal care: extremely preterm infants study in Sweden (EXPRESS)

Aims: The aim of this study was to determine the incidence of neonatal morbidity in extremely preterm infants and to identify associated risk factors. Methods: Population based study of infants born before 27 gestational weeks and admitted for neonatal intensive care in Sweden during 2004–2007. Results: Of 638 admitted infants, 141 died. Among these, life support was withdrawn in 55 infants because of anticipation of poor long‐term outcome. Of 497 surviving infants, 10% developed severe intraventricular haemorrhage (IVH), 5.7% cystic periventricular leucomalacia (cPVL), 41% septicaemia and 5.8% necrotizing enterocolitis (NEC); 61% had patent ductus arteriosus (PDA) and 34% developed retinopathy of prematurity (ROP) stage ≥3. Eighty‐five per cent needed mechanical ventilation and 25% developed severe bronchopulmonary dysplasia (BPD). Forty‐seven per cent survived to one year of age without any severe IVH, cPVL, severe ROP, severe BPD or NEC. Tocolysis increased and prolonged mechanical ventilation decreased the chances of survival without these morbidities. Maternal smoking and higher gestational duration were associated with lower risk of severe ROP, whereas PDA and poor growth increased this risk. Conclusion: Half of the infants surviving extremely preterm birth suffered from severe neonatal morbidities. Studies on how to reduce these morbidities and on the long‐term health of survivors are warranted.     

Placental transfer and decay of varicella-zoster virus antibodies in preterm infants

OBJECTIVES: To compare the placental transfer of maternal varicella-zoster (VZV) antibodies to preterm and term infants and to investigate antibody decay during the first 6 months of life in the preterm infants.Study design: Maternal and umbilical cord blood samples were taken from 113 healthy mother-newborn pairs: 64 term (gestational age > or =37 weeks) and 49 preterm (gestational age < or =35 weeks). Premature infants were further tested at 1, 2, and 6 months. Anti-VZV antibody to membrane antigen was measured with the immunofluorescent technique. RESULTS: Preterm infants of gestational age < or =28 weeks had positive cord antibody and a geometric mean titer significantly lower than those in preterm infants of gestational age 29 to 35 weeks and term infants (25% vs 95% and 95%, respectively, P <.001 for each, and 2.5 +/- 2.2 vs 10.5 +/- 2.4 and 12.6 +/- 2.4, respectively, P <.001 for each). There was no difference between the preterm 29 to 35 weeks of gestation and term groups. Fetal-maternal ratios for both preterm groups were <1 and were significantly less than the fetal-maternal ratio in the term infants. The transfer of maternal antibodies to term infants was significantly greater than to the 29- to 35-week preterm infants (P =.01). At 2 months of age, 25% of 29- to 35-week preterm infants and no preterm infant < or =28 weeks had a positive titer. At 6 months of age, all preterm infants were seronegative, and the geometric mean titer in both groups declined to undetectable levels. CONCLUSION: Transplacental transfer of maternal VZV antibodies is diminished in preterm infants. VZV antibody levels are significantly lower in preterm infants born at < or =28 weeks' gestational age compared with those in preterm infants 29 to 35 weeks' gestational age and term infants. Anti-VZV titers decrease to undetectable levels in preterm infants by 6 months of age or earlier; thus these infants appear to be susceptible to chickenpox before the scheduled 12-month vaccination.     

Fetal malnutrition and its impacts on neonatal outcome in preterm infants

Fetal malnutrition is an important risk factor for both early and late neonatal outcome and adult diseases. In this study, we aimed to investigate the incidence and characteristics of fetal malnutrition and its impacts on early neonatal morbidity and mortality in preterm infants by using the clinical assessment of nutritional status score (CANSCORE). Preterm infants whose gestational ages were between 28-34 weeks were included in the study. Detailed prenatal and natal history, anthropometric measurements, and intrauterine growth status were defined, and CANSCORE was applied to all infants. Infants were separated into two groups according to total score as malnourished (total score < 25) and well nourished (total score > or = 25). Early and late neonatal morbidities, which were observed during the clinical progress, were noted in all infants. A total of 93 preterm infants were enrolled in the study. The incidence of fetal malnutrition was 54.8% (n = 51) in all infants. The incidences of maternal hypertension and preeclampsia, oligohydramnios and disturbed umbilical artery Doppler flow in the prenatal period and the incidences of neonatal hypoglycemia, polycythemia, feeding intolerance, and necrotizing enterocolitis in the postnatal period were significantly higher in preterm infants with fetal malnutrition. Fetal malnutrition contributes significantly to many early and late neonatal morbidities in preterm infants, and it should be identified in every preterm infant in the first days of life for predicting neonatal outcome, even though they are appropriately grown.     

极早产儿初始无创持续气道正压呼吸支持失败的多中心队列研究

目的分析出生胎龄<32周的极早产儿初始无创持续气道正压(CPAP)呼吸支持失败的危险因素及其不良结局。方法采取多中心前瞻性观察性队列研究,收集山东新生儿协作网中30家医院新生儿重症监护病房2019年出生的出生胎龄 25~31⁺⁶周极早产儿的围生期资料、临床救治情况和结局。根据生后初始无创CPAP的结局分为失败组和成功组。采用χ²检验或Fisher确切概率法和非参数检验比较两组间危险因素的差异,并对差异有统计学意义的危险因素进一步进行二元Logistic回归分析。结果共纳入极早产儿 1 040例,其中男577例(55.5%),女463例(44.5%);出生胎龄25~28+6周195例(18.8%),29~31⁺⁶周845例(81.2%);出生体重<1 000 g 81例(7.8%),出生体重≥1 000 g 959例(92.2%)。失败组138例(13.3%),成功组902例(86.7%)。出生胎龄 25~28⁺⁶周、29~31⁺⁶周的初始无创CPAP失败率分别为24.6% (48/195)、10.7% (90/845)。多因素Logistic回归分析显示,较小的出生胎龄、母亲妊娠期高血压疾病、生后发生Ⅲ~Ⅳ级呼吸窘迫综合征(RDS)、需用肺表面活性物质(PS)≥2次、吸入氧浓度>0.30是初始无创CPAP失败的独立危险因素(OR=0.718、1.847、4.003、6.712、1.948,95%CI:0.590~0.873、1.130~3.018、2.435~6.579、3.160~14.259、1.189~3.192,均P<0.05);失败组的病死率和新生儿肺出血、中重度支气管肺发育不良、重度脑室内出血不良结局的发生率均明显高于成功组(OR=4.436、26.393、1.998、4.545,95%CI:2.106~9.344、9.690~71.885、1.031~3.875、1.615~12.795,均P<0.05)。结论出生胎龄<32周的极早产儿初始无创CPAP失败主要不良结局的发生率较高;出生胎龄较小、母亲存在妊娠期高血压疾病,生后发生Ⅲ~Ⅳ级RDS、需用PS≥2次以及吸入氧浓度>0.30的是初始无创CPAP失败的危险因素。     

Early versus late indomethacin treatment for patent ductus arteriosus in premature infants with respiratory distress syndrome

OBJECTIVE: To compare efficacy and side effects of early versus late indomethacin treatment for patent ductus arteriosus (PDA) in premature infants. METHODS: One hundred twenty-seven neonates receiving ventilatory assistance (gestational age: 26-31 weeks) with PDA confirmed by echocardiography were randomly assigned in a prospective multicenter trial to either early (day 3, n = 64) or late (day 7, n = 63) intravenous indomethacin treatment (3 x 0.2 mg/kg every 12 hours). Treatment history and side effects were registered. RESULTS: The PDA closure rate was higher in the early treatment group at both 6 (73% vs 44%, P =.0008) and 9 days of age (91% vs 78%, P =.047). However, there was no significant difference in PDA ligation. Urine output was significantly lower (P <.0001), serum creatinine level was higher (P =.016), and more indomethacin courses were administered in the early treatment group (70 vs 26). Respiratory support, number of deaths, and intraventricular hemorrhages were similar in both groups. However, on the whole, major adverse events (death, necrotizing enterocolitis, and/or localized perforation, extension of hemorrhage, or cystic leukomalacia) occurred more frequently in the early treatment group (P =.017). CONCLUSION: Early indomethacin treatment improves PDA closure but is associated with increased renal side effects and more severe complications and has no respiratory advantage over late indomethacin administration in ventilated, surfactant-treated, preterm infants <32 weeks' gestational age.     

Umbilical cord levels of interleukin-1 receptor antagonist and neonatal outcome

BACKGROUND: Previous studies indicate that there may be infant gender differences in cytokine expression associated with differences in neonatal morbidity. OBJECTIVE: We tested the hypothesis that umbilical cord interleukin-1 receptor antagonist (IL-1ra) correlates with infant gender and neonatal outcome in preterm infants. STUDY DESIGN: IL-1ra was measured in cord blood taken from 58 preterm infants (33 males, 25 females) with gestational age less than 32 weeks. Receiver operating characteristics (ROC) curve were used for identifying IL-1ra values with high sensitivity and specificity for neonatal morbidity and adverse outcome, i.e., death or survival with severe intraventricular hemorrhage or periventricular leukomalacia. RESULTS: In the female infants, but not the male infants, cord IL-1ra values correlated with postnatal depression, expressed as Apgar scores at 1 min (correlation coefficient, r(s); p value: -0.542; 0.005), 5 min (-0.571; 0.018), and 10 min (-0.442; 0.035); and postnatal age at intubation (-0.799; 0.001). The ROC area under the curve (AUC) was 0.735 for adverse outcome (p=0.013), and 0.683 for bronchopulmonary dysplasia (p=0.021) when all infants were included. However, there was a significant gender difference in the ROC curve for adverse outcome (p=0.026), with AUC 0.640 (p=0.240) in males and AUC 0.929 (p=0.008) in females. Above a chosen cutoff at 13,500 ng/l for IL-1ra cord the sensitivity and specificity for predicting adverse outcome was 100 and 81%, respectively in females versus 50 and 84% in males. CONCLUSION: Increased levels of cord IL-1ra levels are associated with neonatal morbidity and adverse outcome in preterm infants. Comparable levels of IL-1ra have different predictive value depending on infant gender.     

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.     

Adverse reactions to immunization with newer vaccines in the very preterm infant

OBJECTIVE: To study the frequency and types of adverse reactions to currently available vaccines in very preterm infants. METHODS: Case notes were obtained for very preterm infants < or =30 weeks' gestational age who received their first immunization at the Royal Women's Hospital, Melbourne, during 1999-2003. Data were extracted for the time periods 48 h before and 48 h after immunizations, with the data extraction blinded as to whether the period being evaluated was pre- or post-immunization. Data collected focused on the frequency and severity of apnoea, respiratory support, fever and clinical consequences of adverse reactions. RESULTS: A total of 48 very preterm infants were immunized during the period; 37 infants had Comvax (Haemophilus influenzae type B and hepatitis B vaccine), Infanrix (diphtheria, tetanus and acellular pertussis vaccine) and inactivated poliomyelitis vaccine, and 11 infants had Comvax and Infanrix only. Their mean (SD) gestational age at birth was 26.4 (1.7) weeks with mean birthweight of 872 (235) g. The mean postnatal age at immunization was 76 (20) days. Low-grade fever (>37.5 degrees C per axilla) occurred in 16 (33%) infants after immunization, but none before immunization (P < 0.001). There was no substantial change in recorded apnoea. No serious adverse events were noted. Four (8%) infants underwent a septic work up post-immunization. The C-reactive protein was increased in all four infants, but other tests for sepsis were negative. CONCLUSION: Fever remains a common adverse event following immunization of the preterm infant in spite of the development of a new generation of vaccines.     

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。     

The contribution of red blood cell transfusion to neonatal morbidity and mortality

Anaemia of prematurity will affect 90% of all very preterm infants, resulting in at least one red blood cell (RBC) transfusion. A significant proportion of preterm infants require multiple transfusions over the course of hospital admission. Growing evidence supports an association between transfusion exposure and adverse neonatal outcomes. In adults, transfusion‐associated sepsis, transfusion‐related acute lung injury and haemolytic reactions are the leading causes of transfusion‐related morbidity and mortality; however, these are seldom recognised in newborns. The association between transfusion and adverse outcomes remains inconclusive. However, the evidence from preclinical studies demonstrates that RBC products can directly modulate immune cell function, a pathway termed transfusion‐related immunomodulation (TRIM), which may provide a mechanism linking transfusion exposure with neonatal morbidities. Finally, we discuss the impact of TRIM on transfusion medicine, how we may address these issues and the emerging areas of research aimed at improving the safety of transfusions in this vulnerable population.     

Lower concentration of pulmonary hepatocyte growth factor is associated with more severe lung disease in preterm infants

OBJECTIVES: Hepatocyte growth factor (HGF) participates in normal lung development and in regeneration after lung injury in animals. We studied the role of HGF during the perinatal period and in the development of bronchopulmonary dysplasia (BPD). STUDY DESIGN: HGF was measured in 172 tracheal aspirate fluid samples (TAF) from 17 preterm infants in whom BPD subsequently developed (gestational age, 27.2+/-1.7 weeks; body weight, 828+/-210 g) and from 15 who survived without BPD (gestational age, 26.8+/-1.9 weeks; body weight, 994+/-265 g) during the first 2 postnatal weeks. RESULTS: Infants with subsequent development of BPD had lower HGF in TAF (45+/-9 pg/mL per IgA-sc) than those surviving without BPD (102+/-32 pg/mL per IgA-sc; P=.028). Lower HGF in TAF were seen in infants with more severe acute respiratory distress as defined as requirement for surfactant therapy (50+/-14 vs 146+/-50 pg/mL per IgA-sc in infants requiring no surfactant; P=.0001), for higher number of surfactant doses (r=-0.16, P=.06), and for mechanical ventilation >1 week (167+/-51 vs 51+/-14 pg/mL per IgA-sc in infants intubated <1 week; P=.0012). CONCLUSIONS: These data show an association between lower HGF concentration in TAF and more severe lung disease in human preterm infants in the early neonatal period.     

Early iron supplementation in very low birth weight infants – a randomized controlled trial

Aim: To evaluate if supplementing iron at 2 weeks of age improves serum ferritin and/or haematological parameters at 2 months of life in very low birth weight (VLBW) infants.
Methods: Preterm VLBW infants who received at least 100 mL/kg/day of oral feeds by day 14 of life were randomized to either 'early iron' (3–4 mg/kg/day orally from 2 weeks) or 'control' (no iron until 60 days) groups. Infants were followed up fortnightly and all morbidities were prospectively recorded. Serum ferritin was measured at 60 days by enzyme immunoassay method.
Results: Forty-six infants were included in the study; primary outcome was available for 42 infants. There was no difference in either serum ferritin (mean: 50.8 vs. 45.3 μg/L; adjusted difference in means: 5.8, 95% CI: −3.0, 14.6; p = 0.19) or haematocrit (32.5 ± 5.3 vs. 30.8 ± 6.3%; p = 0.35) at 60 days between the early iron and control groups. The magnitude of fall in serum ferritin from baseline to the end of study period was also not different between the groups (4.9 vs. 13.8 μg/L; difference in means: 8.8; 95% CI: −0.3, 17.9; p = 0.06). The requirement of blood transfusions (9.5 vs. 13%; p = 0.63) and a composite outcome of common neonatal morbidities (19% vs. 21.7%; p = 0.55) were also not different between the two groups.
Conclusion: Supplementing iron at 2 weeks of age in preterm VLBW infants did not improve either serum ferritin or the haematological parameters at 2 months when compared to the standard practice of starting iron from 8 weeks of age.     

Adverse neurodevelopmental outcome in preterm infants: risk factor profiles for different gestational ages

Aim: Assessment of risk predictors for adverse neurodevelopmental outcome at 1 year of age in preterm infants with a gestational age <30 weeks (Group I) and 30–32 weeks (Group II).
Methods: Between January 2003 and December 2006, we prospectively enrolled 310 live-born infants between 23 and 32 weeks of gestation. The association between candidate risk factors and delayed motor or mental development (Bayley Scales of infant development II; psychomotor or mental developmental index <85) was analysed by means of logistic regression analysis.
Results: Two hundred and fifty infants were eligible for follow-up, and 205 (82.0%) completed the follow-up visit. Intracerebral haemorrhage, small for gestational age and late-onset sepsis were associated with an increased risk for delayed development in Group I (p < 0.05, each). Premature rupture of membranes was a risk condition relevant to Group II. Antenatal steroids were associated with a decreased risk of neurodevelopmental delay in both groups.
Conclusion: This study identified distinct risk factors for adverse outcome in preterm infants of lower (<30 weeks) and higher (30–32 weeks) gestational age. In the lower gestational age group, neonatal risk predictors are most important. Antenatal steroids appear to decrease the risk for adverse outcome in both age groups.     

Intrauterine growth and gestational age in preterm infants with cerebral palsy

In a case-control study, gestational age and intrauterine growth of 191 preterm singleton infants 1971–1982 with cerebral palsy were compared to all preterm live-born singletons in Denmark in 1982 (N = 2203). The distribution of gestational age among preterm cases was slightly bimodal with maximum values at 29 and 32 weeks. The risk for cerebral palsy was highest in the infants with gestational age 28–30 weeks (OR = 5.6 (4.0 – 7.8), 95% confidence interval). Birth weight deviation, in the 34–36 weeks infants, expressed as the number of standard deviations from the mean birth weight for gestational age, was more negative in cases than in controls (P < 0.001). The frequency of small for gestational age (SGA) was 13% in cases and 9% in controls (OR = 1.5 (0.96 – 2.3), 95% confidence interval). The odds for cerebral palsy being SGA, was lower in 28–30 weeks (OR = 0.22 (0.06 – 0.86), 95% confidence interval), the same in 31–33 weeks (OR = 0.83 (0.35 – 2.0), 95% confidence interval) and higher in 34–36 weeks (OR = 5.2 (2.9 – 9.5), 95% confidence interval). In conclusion, preterm infants with cerebral palsy are born earlier than other preterm infants. Small for gestational age is associated with cerebral palsy in preterm infants only above 33 weeks.     

Recombinant erythropoietin and blood transfusion in selected preterm infants

OBJECTIVES: To comprehensively identify preterm infants likely to require blood transfusion and to investigate the effectiveness of recombinant erythropoietin in this high risk subgroup. DESIGN: Double blind randomised controlled trial. SETTING: Neonatal Intensive Care Unit, Middlemore Hospital, Auckland, New Zealand. PATIENTS: Preterm infants < 33 weeks gestation and < 1700 g birth weight meeting specific criteria indicating a high possibility of requiring blood transfusion. INTERVENTIONS: Predictors of blood transfusion were determined by analysis of preterm infants admitted to a neonatal intensive care unit over a two year period. Using the criteria developed, high risk infants entered the study and received erythropoietin or sham treatment until 34 weeks completed gestation. The sample size was calculated to detect a reduction of one blood transfusion per infant (significance level 5%, power 80%). RESULTS: The selection criteria had a positive predictive value for transfusion of 91% and a negative predictive value of 94%. Mean birth weights and gestational ages were similar in the two groups. Absolute reticulocyte counts and haemoglobin values were higher in the group receiving erythropoietin. There was no significant difference in the number of blood transfusions received in the treatment and control groups. However, comparing transfusions given to < 1000 g infants after 30 days of age, there were significantly fewer transfusions in the erythropoietin group (mean (SD) 0.5 (0.7) in those receiving erythropoietin and 1.6 (1.1) in the controls). No adverse effects were noted. CONCLUSIONS: The selection criteria for the study were highly predictive of subsequent transfusion. In the group receiving erythropoietin, a reduction in transfusion requirements was apparent only in the < 1000 g birthweight group after 1 month of age.     

胎龄<32周早产儿中重度支气管肺发育不良危险因素的多中心回顾性分析

目的 分析胎龄<32周早产儿中重度支气管肺发育不良（bronchopulmonary dysplasia,BPD）的危险因素。 方法 回顾性收集2019年1月1日至2020年12月31日江苏省新生儿围产期协作网17家单位新生儿重症监护室收治的胎龄<32周且住院时间≥28 d诊断为BPD早产儿的临床资料,依据胎龄和BPD严重程度分组,采用多因素logistic回归分析不同胎龄段发生中重度BPD的危险因素。 结果 2年间17家协作单位新生儿重症监护室收治的胎龄<32周早产儿共2 603例,诊断BPD的961例,BPD发生率为36.92%（961/2 603）,中重度发生率为8.64%（225/2 603）,24⁺⁰~25⁺⁶周早产儿中重度BPD发生率为56.5%（26/46）,26⁺⁰~27⁺⁶周早产儿中重度BPD发生率为31.0%（66/213）,28⁺⁰~29⁺⁶周早产儿中重度BPD发生率为16.9%（75/445）,30⁺⁰~31⁺⁶周早产儿中重度BPD发生率为22.6%（58/257）。多因素logistic回归分析显示,各胎龄段早产儿中重度BPD危险因素不尽相同：24⁺⁰~25⁺⁶周为需治疗的动脉导管未闭;26⁺⁰~27⁺⁶周为胎膜早破≥18 h、复苏正压通气、临床败血症、机械通气时间≥14 d;28⁺⁰~29⁺⁶周为机械通气时间≥14 d、新生儿肺炎、需治疗的动脉导管未闭;30⁺⁰~31⁺⁶周为复苏正压通气、新生儿肺炎、早产儿贫血（均P<0.05）。 结论 胎龄<32周早产儿中重度BPD是多种因素共同作用的结果,并且每个胎龄段存在不尽相同的高危因素,对不同胎龄段提前采取有针对性举措,将有助于减轻BPD严重程度。     

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.     

Feeding problems in preterm infants of preeclamptic mothers

Aim: Maternal disease can cause prematurity and neonatal complications, notably feeding problems. To determine the relationship between maternal disease and the nature and severity of neonatal feeding problems, we compared feeding profiles, time to demand feeding and length of hospital stay between preterm infants of preeclamptic mothers, mothers with amniotic infection and mothers with other disease causing prematurity. Methods: The retrospective study used labour ward data collected from 2002 to 2005 in a tertiary university centre to analyse three groups of singletons born at <32 completed gestational weeks to mothers with preeclampsia (n = 61), amniotic infection (n = 55) and non‐preeclamptic non‐amniotic infection controls (n = 55). The groups were similar in gestational age, birthweight and sex ratio; all infants received enteral feeding according to departmental guidelines. Feeding profiles and enteral/oral nutrition were compared. Results: Feeding problems occurred in 46% of the preeclamptic group, 11% of the amniotic infection group and 13% of controls. Full oral demand feeding was established at 36 0/7 weeks postmenstrual age, 35 3/7 weeks (P = 0.03) and 35 2/7 weeks (P < 0.0001), respectively. Feeding problems were the main cause of delay (7–10 days) in hospital discharge in the preeclamptic group (P = 0.0002). Conclusions: Feeding problems are greater, and hospital stay longer, in preterm infants of preeclamptic mothers than in other preterm infants.     

Validation of actigraphy for determining sleep and wake in preterm infants

Background: Actigraphy has been widely used in adults and children for the determination of sleep and wake. However, there have been limited studies in infants and to date there have been no studies to validate the reliability of actigraphy in preterm infants.
Aim: To evaluate the usefulness of actigraphy in preterm infants in a neonatal unit setting for determining sleep–wake by comparing results with those recorded from behavioural observations.
Methods: Thirty-eight studies were carried out in 10 preterm infants (8M/2F) born at 29–34 weeks gestational age. Sleep–wake patterns were assessed over 24 h with behavioural observations and compared to actigraphy (Actiwatch AW64, Mini Mitter Company Inc., Sunriver, OR, USA). The studies were grouped into gestational ages 30–33 weeks (n = 8), 34–36 weeks (n = 20) and 37–40 weeks (n = 10).
Results: Overall, on the low-activity threshold we found agreement rates of 84.5–88.9% between actigraphy and behavioural scoring with the predictive value for determining sleep (PVS) being between 91.3% and 95.6% and sensitivity between 88.2% and 96.8%. However, the actiwatch was not reliable for determining wakefulness with low values for predictive value of wake (PVW,31.1–53.7%) and specificity (31.5–33.6%).
Conclusion: Actigraphy can be used as a reliable indicator of sleep patterns in preterm infants in the neonatal unit setting.