Actigraphy correctly predicts sleep behavior in infants who are younger than six months, when compared with polysomnography

Actigraphy has been widely used in adults and children. In infants, validation of actigraphy has typically used a comparison with behaviorally determined sleep state classification rather than polysomnography (PSG). This study validated actigraphy against PSG for determining sleep and waking states in infants who were younger than 6 mo. Twenty-two healthy infants, 13 term and 9 preterm, were studied at three different matched postconceptional ages. Actigraph data were compared with PSG recordings in 1-min epochs. Agreement rate (AR), predictive value for sleep, predictive value for wake, sensitivity. and specificity were calculated and compared between activity thresholds and across ages with two-way ANOVA for repeated measures. Thirty-two validation studies were analyzed. Overall AR with PSG of 93.7 +/- 1.3 and 91.6 +/- 1.8 were obtained at 2-4 wk and 5-6 mo, respectively, at the low activity threshold setting, whereas the auto activity threshold gave the best agreement with PSG at 2-4 mo (AR 89.3 +/- 1.3%). Sensitivity values of 96.2 +/- 1.1% at 2-4 wk, 91.2 +/- 1.5% at 2-4 mo, and 94.0 +/- 1.9% were obtained at these same settings. There was no difference across ages in AR or sensitivity. PVW and specificity values were low in this study. We conclude that actigraphy is a valid method for monitoring sleep in infants who are younger than 6 mo.     

Apnoea of prematurity and arousal from sleep

The incidence of sudden infant death syndrome (SIDS) has been found to be consistently higher in preterm and low birth weight infants than in infants born at term and this increase is inversely related to gestational age. The incidence and severity of apnoea of prematurity, are also inversely related to gestational age. The aim of this study was to investigate whether a neonatal history of apnoea/bradycardia affected the maturation of arousal responses. Twenty-five premature infants were studied. A perinatal risk score was determined for each infant and infants were divided into those with a neonatal history of apnoea/bradycardia (n=16) and those without (n=9). All infants were studied using daytime polysomnography on three occasions: (a) a preterm study around 36 weeks gestation, (b) within 3 weeks of term, and (c) 2-3 months post-term. Multiple measurements of arousal threshold (cm H2O) in response to air-jet stimulation applied alternately to the nares were made in both active sleep (AS) and quiet sleep (QS). Arousal thresholds were elevated in apnoeic infants compared to control infants in both AS (P<0.05) and QS (P<0.001) at the term study and in QS at 2-3 months post-term (P<0.01). In addition, arousal thresholds were positively correlated with perinatal risk score in both sleep states, in all studies, with the exception of AS at 2-3 months when all infants were readily arouseable. We conclude that a history of prematurity with neonatal apnoea has a persisting effect on decreasing arousabilty from sleep and these infants may be at increased risk for SIDS.     

Measurement of transepidermal water loss in Tanzanian cot-nursed neonates and its relation to postnatal weight loss

In healthy cot-nursed Tanzanian neonates ( n = 92, gestation 26–42 weeks) measurements of transepidermal water loss (TEWL) and weight change were performed during the first 24 h after birth at an average ambient humidity of 70% and an environmental temperature of 32°C. Urine production on day 1 (ml/kg per 24h) was documented for a subgroup of 13 preterm and 8 term infants. In a limited group of preterm infants ( n = 5) TEWL measurements, weight and 24 h urine volume measurements were repeated daily for 7 days. Maximum weight loss was determined in 7 preterm (gestational age 30–36 weeks) and 6 term infants. TEWL was estimated by measuring the evaporation rate at three sites of the body using the water vapour pressure gradient method. On day 1, TEWL was highest in the most preterm infants, whereas TEWL and urine production were higher in large for gestational age infants as compared to appropriate for gestational age (AGA) infants of the same gestational age (31–36 weeks). For the whole group, weight loss on day 1 was correlated with TEWL ( r = 0.49, p <0.05). At follow-up TEWL in preterm infants remained almost constant during the first 4 days and decreased after the fourth day, at which time weight gain commenced. Preterm AGA infants (gestational age 24–37 weeks) showed a mean postnatal weight loss of 4.4% of the birth weight, while in term infants this loss was only 2.6%. A reduced postnatal weight loss as compared to Caucasian infants may be explained by a lower water loss during the first days after birth, through both skin evaporation and urine excretion.     

胎膜早破极早产儿的临床特征和主要不良结局的预测因素分析

目的 探讨胎膜早破(prelabor rupture of membranes,PROM)极早产儿的临床特征及其发生早发型败血症(early-onset sepsis,EOS)和死亡的预测因素.方法 回顾性收集2018年1月至2020年5月入住新生儿重症监护室的PROM极早产儿(胎龄<32周)的临床资料.根据胎膜破裂至...     

不同胎龄早产儿生后24 h内血小板及相关参数参考范围

目的 研究不同胎龄早产儿生后24 h内血小板及相关参数参考范围并探讨其临床意义。方法 根据纳入标准和排除标准,收集2018年1~12月入住新生儿重症监护室且出生胎龄为23~36⁺⁶周早产儿1 070例的临床资料进行回顾性分析,观察生后24 h内不同胎龄早产儿血小板参数参考范围。结果 不同胎龄早产儿血小板计数（PLT）及血小板压积（PCT）水平比较差异无统计学意义（P > 0.05）;晚期早产儿组（34~36⁺⁶周,n=667）血小板平均体积（MPV）及血小板体积分布宽度（PDW）均低于极早早产儿组（23~27⁺⁶周,n=36）和早期早产儿组（28~33⁺⁶周,n=367）（P < 0.05）。不同性别早产儿之间血小板及相关参数比较差异均无统计学意义（P > 0.05）。按照不同胎龄来计算早产儿血小板参数的参考范围,23~36⁺⁶周早产儿PLT参考范围为（92~376）×10⁹/L,PCT参考范围为0.1%~0.394%;23~33⁺⁶周早产儿MPV参考范围为9.208~12.172 fl,PDW参考范围为8.390%~16.407%;34~36⁺⁶周早产儿MPV参考范围为9.190~11.950 fl,PDW参考范围为9.046%~15.116%。结论 不同胎龄早产儿生后24 h内MPV及PDW不同,依据胎龄制定早产儿MPV及PDW参考范围更有助于指导临床工作。     

Free-radical-induced lipid peroxidation during the early neonatal period

The effect of gestational age on postnatal free-radical-mediated lipid peroxidation was studied in 19 term (gestational age 37–42 weeks) and 21 healthy preterm (gestational age 31–36 weeks) infants by measurement of expired ethane and pentane during the first 7 days of life. Ethane (11.9 versus 5.7 pmol/kg/min; p = 0.0001) and pentane (11.4 versus 7.5 pmol/kg/min; p = 0.01) were significantly higher in preterm than in term infants. Correlations were found between gestational age and ethane ( r = 0.60, p = 0.0001) for days 1–7 and pentane ( r = 0.54, p = 0.0003) for days 3–7; and between birth weight and ethane ( r = 0.58, p = 0.0001) and pentane (r = 0.55, p = 0.0003). These results indicate that during the postnatal period, immaturity is a major factor determining the rate of free-radial-mediated lipid peroxidation.     

Plasma somatostatin and cholecystokinin levels in sick preterm infants during their first six weeks of life

Abstract The present study reports the levels of plasma somatostatin and cholecystokinin in 19 preterm infants with asphyxia [ n =10, GA (median; range) 26; 23–30 weeks] and respiratory distress syndrome ( n = 14, GA 27; 23–29 weeks) compared with preterm infants without any of these conditions (reference group, n = 59, GA 33; 25–36 weeks). In the reference group 37 infants received phototherapy and their peptide levels were compared with those not receiving phototherapy ( n = 22). Plasma somatostatin and cholecystokinin were analysed by specific radioimmunoassays on day 1, day 3–4 and at 6 weeks of life. Plasma somatostatin levels, but not cholecystokinin levels, of reference infants were inversely related to gestational age on day 1 and day 3–4. Asphyxiated infants and infants with respiratory distress syndrome had significantly higher somatostatin levels than reference infants on day 1 and day 3–4. These differences disappeared when the levels were adjusted for gestational age. Plasma cholecystokinin levels were not influenced by respiratory distress syndrome and asphyxia. Phototherapy did not affect plasma somatostatin and cholecystokinin levels.     

Infantile hydrocephalus in preterm, low-birth-weight infants—a nationwide Swedish cohort study 1979–1988

All Swedish infants with shunt-treated infantile hydrocephalus, born during the period 1979–88 at 34 weeks gestational age and of low birth weight, were studied. Ninety-six infants were born before 32 weeks and 50 at 32–34 weeks. The mean gestational age in the very preterm group gradually decreased from 29.5 to 27.3 weeks. The mean live birth prevalence was 15.9 per 1000 very preterm infants, and 5.1 per 1000 moderately preterm infants. No significant secular prevalence trends were found. The perinatal mortality decreased successively. The slowly decreasing trend in moderately preterm infants may imply better outcome in survivors. The slightly increasing trend in very preterm infants could be explained by more survivors in the low gestational age group. The aetiology was considered perinatal in 94% of the very preterm group and in 56% of the moderately preterm group; prenatal in 1% and 32% of infants, respectively. Additional neuropimairments were present in 82% of infants, cerebral palsy being the commonest (74%).     

Early amplitude-integrated EEG correlates with cord TNF-α and brain injury in very preterm infants

Aim: To investigate if the early electroencephalogram (EEG) and amplitude-integrated EEG (aEEG) in very preterm infants is affected by perinatal inflammation and brain injury, and correlates with long-term outcome.
Methods: Sixteen infants born at 24–28 gestational weeks (median 25.5) had continuous EEG/aEEG during the first 72 h of life. Minimum and maximum EEG interburst intervals (IBI), and aEEG amplitudes were semi-automatically quantified and averaged over the recording period. Neonatal brain injury was diagnosed with repeated cranial ultrasound investigations. Nine cytokines from four time-points were analyzed during the first 72 h (umbilical cord blood, 6, 24 and 72 h), and outcome was assessed at 2 years of corrected age.
Results: Infants with neonatal brain injury (n = 9) had prolonged IBI, 11.8 (9.6–23.2) sec versus 8.2 (7.1–11.6) sec in infants (n = 7) without brain damage (p = 0.005). Handicap at 2 years (n = 8, including two infants without neonatally diagnosed brain injury) was associated with prolonged neonatal IBI and lower aEEG amplitudes. Also aEEG amplitudes were decreased in infants with neonatal brain injury. There was a significant positive correlation between the averaged IBI and cord blood TNF-α (rs = 0.595, p = 0.025).
Conclusion: Early EEG depression is associated with increased cord blood TNF-α, neonatal brain damage and handicap at 2 years.     

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.     

Successful breastfeeding after discharge of preterm and sick newborn infants

AIM: To determine the extent and duration of breastfeeding in preterm and sick newborn infants admitted to a level IIb neonatal unit (NU). METHOD: Hospital-based follow-up of 1730 infants born in 1996, 2001 and 2004, and studied from discharge to 6 months of post-natal age. RESULTS: At discharge from the NU, 98% of term (n = 945) and 92% of preterm (n = 785) infants were exclusively or partly breastfed. Exclusive breastfeeding increased at 2 months of corrected post-natal age and 78% of term infants were still exclusively or partly breastfed at 6 months of corrected post-natal age. Duration of breastfeeding among preterm infants was significantly shorter than in infants born at term. However, even among extremely preterm infants with a gestational age <28 weeks, 41% were still breastfeeding, exclusively or in part, at 6 months of post-natal age. There was no difference in breastfeeding after neonatal care in 1996 as compared to 2004. Moreover, the study showed that the breastfeeding after neonatal care differed only slightly from population data for all infants in Sweden. CONCLUSION: Breastfeeding can be successfully established in most preterm and previously sick neonates.     

Nitric oxide levels in preterm and term infants and in premature infants with bacteremia

OBJECTIVE: To determine the serum nitric oxide levels in healthy neonates and in infants with bacteremia. METHODS: We performed a prospective study in a tertiary neonatal intensive care unit. The serum nitric oxide levels were measured in all infants at birth (basal) and in the infected neonates also on the first 2 days of bacteremia. RESULTS: Thirty-three neonates (10 term, 23 preterm) were included. Eleven preterm infants (mean gestational age 27 weeks) had bacteremia. The main blood culture isolates included coagulase-negative staphylococci (n=4), Klebsiella pneumoniae (n=3), and Escherichia coli (n=3). The serum nitric oxide levels increased during infection in 10 infants (p <0.008). The mean nitric oxide level before infection was 44 microM and during infection 96 microM (p=0.008). In the healthy babies, the mean nitric oxide level was 26 microM in those with a gestational age <27 weeks, 44 microM in those born between 28 and 36 weeks of gestation, and 63 microM in term infants. CONCLUSIONS: Bacteremic preterm infants produce significantly higher amounts of nitric oxide. The basal nitric oxide levels at birth may be correlated with gestational age.     

Prone or supine for infants with chronic lung disease at neonatal discharge?

OBJECTIVE: To determine whether infants with chronic lung disease (CLD), ready for neonatal unit discharge, maintain cardiorespiratory stability while sleeping supine. METHODS: Subjects were 15 infants born < 32 weeks gestational age (GA) and ready for discharge from the regional tertiary neonatal intensive care unit. Polysomnography recordings of sleep state, heart rate, arterial oxygen saturation, respiratory effort and nasal/oral airflow were taken prone and supine for up to 3 h post feed with the first position randomly allocated. The main outcome measures were oxygen saturation and apnoea hypopnoea index (AHI). RESULTS: Seven infants (median GA 27 weeks, birthweight 945 g) had CLD and eight infants (median GA 29 weeks, birthweight 1160 g) did not. CLD infants were more mature at study than non-CLD infants (median 39 vs 36 weeks, P = 0.019). Neither oxygen saturation nor AHI were position dependent and no group differences were noted with respect to CLD status. There was a significant interaction of GA and sleep position with less-mature infants spending less time in quiet sleep (QS) in supine position (P = 0.006). These less-mature infants also had a higher AHI (P = 0.033). As expected, the AHI and arousal index (AI) were higher in active sleep (P < or = 0.001, P = 0.013, respectively) and mean oxygen saturation was lower (P = 0.001). CONCLUSIONS: The supine position appears appropriate for very preterm infants with CLD going home from the neonatal unit. Respiratory instability on neonatal discharge is more likely to be associated with immaturity than CLD.     

Home oxygen therapy after preterm birth in Western Australia

OBJECTIVES: To review our management of infants discharged home receiving supplemental oxygen. Stable preterm infants receive low flow O(2) by nasal cannulae aiming for SaO(2) of > or = 95%. Oxygen-dependent infants must pass an air test (ability to maintain SaO(2) > 80% during 4 h disconnection from oxygen) before discharge home with supplemental oxygen. A sleep study is performed before nocturnal O(2) is ceased. METHODS: Infants less than 33 weeks gestational age (GA) who were admitted January 1999-June 2001 and discharged home with supplemental oxygen were identified through the databases and medical records of the King Edward Memorial/Princess Margaret Hospitals. The data collected were compared with an audit performed a decade earlier. RESULTS: Ninety-three infants were discharged home with supplemental oxygen between 1999 and 2001 (10% neonatal intensive care unit admissions less than 33 weeks GA; median GA 26 weeks (interquartile range 25-28). All infants had an air test before discharge: 63% failed the first air test and 30% at least two air tests. The median delay between the first air test and discharge was 2 weeks. The median postmenstrual age at discharge was 40 weeks gestation (interquartile range 38-41). Ninety infants had a sleep study before nocturnal oxygen was ceased and nine failed the first sleep study. Hospital readmission rate was 60%. More preterm infants (less than 33 weeks) were discharged with supplemental oxygen in 1999-2001 (10%, n = 96 in 1999-2001) than in 1987-1992 (2.5%, n = 53) and this was associated with an earlier discharge (40 vs 44 weeks postmenstrual age), lower oxygen requirements at discharge (60 vs 125 mL/min), earlier discontinuation of daytime and nocturnal oxygen (1 vs 4 months postmenstrual age and 2.5 vs 6 months postmenstrual age) and no increase in readmission rate (64% vs 60%). The incidence of bronchopulmonary dysplasia for these infants has remained stable at 20%. CONCLUSION: Our home oxygen programme, based on an air test predischarge and a sleep study prediscontinuation of nocturnal oxygen, facilitates early discharge home. Our data suggest that over the last decade, bronchopulmonary dysplasia is associated with less impairment in lung function. Further evidence from randomized clinical trials is required to determine optimal target range for oxygen saturation in preterm infants.     

早产儿中性粒细胞活性氧代谢的研究

目的：该研究通过对于不同胎龄新生儿中性粒细胞活性氧代谢水平的检测研究,以了解新生儿中性粒细胞功能发育成熟的过程,并探讨早产儿对于细菌高易感性的部分原因。方法：选择早产儿35例,分为胎龄32周以下和33～36周两组,并选择足月新生儿23例作为对照组。在新生儿出生后取脐静脉血进行体外实验,分别以金黄色葡萄球菌和大肠杆菌刺激诱导呼吸爆发后用超氧阴离子特异性探针氢化溴乙非锭进行细胞内染色,通过流式细胞仪检测中性粒细胞超氧阴离子阳性细胞比率和产生水平;同时对两组不同胎龄早产儿细菌感染实际发生情况进行比较。结果：胎龄32周以下早产儿超氧阴离子阳性中性粒细胞比率与胎龄32周以上早产儿和足月新生儿相比差异有显著性,呈明显低下状态［金黄色葡萄球菌:（79.4±8.6）% vs （89±6.1）% vs （91.3±3.8）%,F＝18.05,P＜0.01;大肠杆菌: （78.2±7.8）% vs （89.3±5.3）% vs （92±4.1）%,F＝28.3, P＜0.01)］;而且阳性率和早产儿胎龄大小密切相关(y＝2.66 x ,P＜0.01);但3组不同胎龄的新生儿活性氧代谢阳性细胞超氧阴离子产生水平之间的差异无显著性。临床观察发现小胎龄早产儿组全身性细菌感染实际发生率高于大胎龄组早产儿。结论：新生儿中性粒细胞细菌诱导活性氧代谢的总体能力直接和新生儿成熟度相关,在胎龄小于32周早产儿中处于明显低下状态,并随着胎龄的增加逐渐成熟。早产儿中性粒细胞活性氧代谢水平的总体低下是导致早产儿细菌感染高易感性的重要原因之一。［中国当代儿科杂志,2007,9（4）：355-357］     

Cocaine use in pregnancy in Amsterdam

To study the effects of cocaine use in pregnancy in Amsterdam, clinical data on cocaine-using pregnant women ( n = 21) and their offspring ( n = 23) were obtained retrospectively (1987–1994) at the Academic Medical Center, Amsterdam. Infants exposed to cocaine had a median gestational age of 39 weeks and a median birth weight of 3090 g. There were six preterm infants, two small-for-gestational-age infants and five infants with a small head circumference. Three infants had a congenital malformation. One infant (Potter's syndrome) died shortly before birth. One infant had congenital syphilis, four had intracerebral abnormalities on ultrasound and four had abnormal neurologic symptoms in the neonatal period. One infant died after 21 days of life. At follow-up four infants showed abnormal development. In 12 of the 23 infants (52%), one or more possible effects of cocaine were found.     

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.     

Longitudinal measurements of bone status in preterm infants

BACKGROUND: Quantitative ultrasound measurement of the speed of sound (SOS) through bone has been investigated as a means of assessing bone status in preterm infants. Few studies report longitudinal measurements. OBJECTIVE: To assess longitudinal changes in bone SOS in preterm infants. METHODS: Sixty preterm infants with gestational ages of < 33 weeks and with birth weight appropriate for gestational age (AGA), and 48 healthy, term AGA infants were enrolled. SOS measurements of the tibia were made within the first week of life in the preterm infants, and within the first 72 hours of life in the term infants. During their hospital stay, weekly measurements of tibial SOS were made in 29 of the preterm infants, who were divided into three gestational age groups: Group 1: 24-26 weeks (n = 8), Group 2: 27-29 weeks (n = 9), and Group 3: 30-32 weeks (n = 12). RESULTS: The median SOS value for the 60 newborn preterm infants was significantly lower than that for the 48 newborn term infants (2,924 versus 3,036 m/sec, p < 0.001). At each time point, SOS values for each of the preterm infant gestational age groups were significantly lower than the term newborn infant SOS values. SOS values decreased significantly over time for the entire cohort of 29 preterm infants (p < 0.001), and for Groups 1 (p = 0.015) and 2 (p = 0.003). At several time points, there was a significant negative correlation between serum alkaline phosphatase levels and SOS values, and a significant positive correlation between serum phosphorus levels and SOS values. CONCLUSION: SOS measurements of the tibia decline during hospitalization in preterm infants, suggesting a progressive loss of bone strength. Longitudinal measurements of bone SOS in combination with serum alkaline phosphatase and serum phosphorus levels may identify infants at risk of developing osteopenia of prematurity.     

Preterm infants with low immunoglobulin G levels have increased risk of neonatal sepsis but do not benefit from prophylactic immunoglobulin G

OBJECTIVE: In a prospective, randomized, placebo-controlled, multicenter study, we evaluated the prevention of neonatal infections with intravenous immunoglobulin G (IVIgG) prophylaxis for preterm infants (gestational age <33 weeks) with umbilical cord blood IgG levels < or =4 g/L. STUDY DESIGN: Intravenous IgG or placebo (albumin), 1 g/kg body weight, was given on days 0, 3, 7, 14, and 21 to 81 infants with umbilical cord blood IgG levels < or =4 g/L: (1) IVIgG group, n = 40, mean (SD) gestational age 27.5 (2.2) weeks and birth weight 1.06 (0.39) kg; (2) placebo group, n = 41, mean (SD) gestational age 27.7 (2.5) weeks and birth weight 1.13 (0.38) kg. Infants with umbilical cord blood IgG levels >4 g/L (n = 238) served as a separate comparison group. Neonatal infections according to European Society of Pediatric Infectious Disease criteria were monitored until 28 days of life. RESULTS: Infants with IgG levels < or =4 g/L at birth who received IVIgG had no significant reduction in infectious episodes or mortality rate when compared with those given placebo. However, infants with a serum concentration of IgG >4 g/L at birth had significantly fewer infectious episodes (culture-proven sepsis) than infants with low serum concentrations of IgG (< or =4 g/L) when compared at the same gestational ages (26 to 29 weeks, P <.003). CONCLUSIONS: Prophylactic immunotherapy with IVIgG did not improve the immune competence in preterm infants with low serum IgG concentrations at birth. We speculate that a spontaneously high serum IgG concentration at birth reflects placenta function and is an indicator of a more mature immune system capable of protecting the preterm infant against severe neonatal infections.     

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。