Lena Hellström-Westas

Preterm male infants need more initial respiratory and circulatory support than female infants

Aim: The aim of this study was to investigate possible gender‐related differences in clinical parameters during the first week of life that could explain the higher morbidity and mortality of preterm male infants. Methods: In total, 130 clinical variables were collected from 236 inborn infants (130 male and 106 female infants) with gestational age (GA) >29wk. A subgroup of 175 extremely low birthweight infants (ELBW) >1000 g (n= 86 males; n= 89 females) was analysed separately. Results: At 6 postnatal h, 60.8% of the male infants needed mechanical ventilation versus 46.2% of the females (p= 0.026). Chronic lung disease (CLD) developed in 36.2% of males versus 9.8% of female infants (p= 0.004). Inotrope support with dopamine was used in more than 50% of the infants; additional inotrope support to dopamine was needed by 19.4% of male and 9.7% of female infants (p= 0.041). The gender‐related difference in need for inotrope support was more evident among the ELBW infants; 67.1% of male infants needed inotrope support versus 50.6% of females (p= 0.028). At 12–24 h, male ELBW infants had lower minimum mean arterial blood pressure (mean (SD) 25(4) mmHg vs 28(6) mmHg, p= 0.004)) and lower minimum PaCO2 than females infants (4.3 (1.1) kPa vs 4.7 (0.9) kPa, p= 0.043).

An Atlas of Amplitude-integrated EEGs in the newborn

1. Methodology. 2. The Electrocortical Background, Its Normal Maturation, Classification, and Effects of Medication. 3. Pitfalls and Caveats. 4. Seizures. 5. Hypoxia-ischemia. 6. Focal Hemorrhagic and Ischemic Lesions in the Full-term Infant 7. Hemorrhagic and Ischemic Lesions in the Preterm Infant. 8. Metabolic Diseases, Brain Malformations, and Central Nervous System Infections.

Comparison between tape-recorded and amplitude-integrated EEG monitoring in sick newborn infants

In 15 ill newborn infants a comparison between long‐term multichannel and single‐channel recordings of simultaneously tape‐recorded (Medilog system) and amplitude‐integrated EEG (Cerebral Function Monitor) was made. There was good agreement between the main type of background activity diagnosed with the tape‐recorded and the amplitude‐integrated EEG for all recordings. Two infants had repetitive subclinical and subtle seizure activity, lasting for several hours, which was detected by both techniques. Short, single seizures were diagnosed in the recordings of nine infants. When a single electrographic seizure appeared in an otherwise stable recording, it was identified by both the tape‐recorded and the amplitude‐integrated EEG. Very short (5‐30 s) seizure patterns, which were diagnosed with the tape‐recorded EEG, were not identified in the cerebral function monitor recordings. In the single‐channel recordings of both the EEG and the cerebral function monitor there were, on some occasions, difficulties in distinguishing single seizures from interference due to external artefacts. In the multichannel recordings the diagnosis of seizure patterns was facilitated by comparison with the other channels. Both the Medilog EEG and the cerebral function monitor are feasible techniques for following cerebral electrical activity in sick neonates, although neither technique is specifically constructed for this purpose. For clinical use in the neonatal intensive care unit the advantage with the cerebral function monitor is the immediately available recording. The tape‐recorded EEG offers possibilities of more channels and a higher reliability when diagnosing short subclinical seizures, however, only after offline analysis.

Fetal gender and gestational-age-related incidence of pre-eclampsia.

Background. Male fetal gender is associated with an overall increased risk of pre‐eclampsia. However, it was recently shown that the male: female birth ratio was decreased in pre‐eclampsia associated with preterm delivery. The reason for this discrepancy is not known. Objective. To investigate whether the fetal and newborn gender is associated with the incidence of antenatal maternal pregnancy complications, and to investigate if gender‐associated risk changes with gestational age at delivery. Methods. Population‐based study including 1,158,276 infants born in Sweden 1990–2001. Five maternal diagnosis groups (pre‐eclampsia, infection, preterm premature rupture of membranes, abruptio placentae, and polyhydramnios) were explored in relation to newborn infant gender and gestational age at delivery. Results. When all gestational ages were evaluated, male newborn gender was associated with increased odds ratios for all five diagnosis groups, and for preterm birth before 37 weeks gestation, M/F ratio 1.17. In very preterm births (gestational age below 32 weeks), male newborn gender was associated with a significantly lower risk for pre‐eclampsia (OR 0.88, 95%CI 0.80–0.97), and a marginally lower risk for polyhydramnios (OR 0.74, 95%CI 0.54–1.01). Conclusion. The fetal gender seems to affect the occurrence of pre‐eclampsia, and possibly also polyhydramnios. The finding could be due to an increased risk for spontaneous abortions in pregnancies with male fetuses, but could also be associated with the etiology of these conditions. Evaluation of antenatal pregnancy complications from a fetal/newborn gender perspective may contribute to new insights regarding their pathophysiological mechanisms.

Inflammation at birth and the insulin-like growth factor system in very preterm infants.

Background: Foetal inflammation is associated with an increased risk of brain damage in preterm infants whereas IGF‐I is essential for cerebral development and exhibits anti‐apoptotic properties.

Long-Distance Transports of Newborn Infants with Congenital Heart Disease

Abstract. Little has been published about specific problems that may occur during long-distance transports of newborn cardiac patients. During a 4-year period after centralization of pediatric heart surgery in Sweden, 286 transports were prospectively investigated. A majority (77.3%) of the transports were carried out by nonspecialized teams. Ten severe adverse events, including the death of 1 infant, occurred during the 286 transports (3.5%). Another infant died later of cerebral complications from hypoxia, rendering a transport-related mortality of 0.7%. Twenty-two infants (7.7%) were severely hypoxic (oxygen saturation ≤65%) at arrival, and 12 of these infants suffered from transposition of the great arteries. During the second 2-year period increased use of intravenous prostaglandin E1 and transportation from tertiary-level units was associated with better transport outcome. During the same time period, overall 30-day postoperative mortality for pediatric cardiac surgery decreased from 4.0% to 1.2% in our hospital. When highly specialized treatment is centralized for quality reasons it is also important that risks associated with transport are considered and that the quality of transport is high. For some cardiac malformations antenatal diagnosis and referral of the mother for delivery to a center with pediatric cardiac surgery would probably further increase the chance of healthy survival in some infants.

No indications of increased quiet sleep in infants receiving care based on the Newborn Individualized Developmental Care and Assessment Program (NIDCAP)

It has been proposed that the developmentally supportive care of very‐low‐birthweight (VLBW) infants provided by the Newborn Individualized Developmental Care and Assessment Program (NIDCAP) can improve the infants opportunities for rest and sleep. The aim of the present study was to determine whether quiet sleep (QS) in VLBW infants is affected by NIDCAP care. Twentytwo infants with a gestational age of <32 wk at birth randomly received either NIDCAP (n= 11) or conventional care (n= 11). These two groups were comparable (mean (SD)) with respect to birthweight (1021 (240) vs 913 (362) g, respectively) and gestational age (27.1 (1.7) vs 26.4 (1.8) wk). The infants in the NIDCAP group were cared for in a separate room by a group of specially trained nurses and subjected to weekly NIDCAP observations until they reached a postconceptional age (PCA) of 36 wk. Quiet sleep (QS) was assessed from 24‐h amplitude‐integrated EEGs recorded at 32 and 36 wk of PCA. The percentage of time [mean (SD)] spent in QS at 32 wk of PCA was 33.5 (2.6) % for the NIDCAP group and 33.3 (6.9)% for the control infants (ns). At 36 wk, the corresponding values were 24.5 (3.2)% and 25.7 (4.7)%, respectively (ns). The number of QS periods/24 h decreased equally in both groups in association with maturation: from 24.6 (3.3) to 16.8 (1.8) and from 25.0 (5.8) to 17.5 (3.3), at 32 wk, and 36 wk of PCA, respectively (NS).

Reduced postnatal cerebral glucose metabolism measured by PET after asphyxia in near term fetal lambs

The effects of fetal asphyxia on cerebral function and development, involve the transition from fetal to neonatal life. Changes in cerebral glucose metabolism may be an early postnatal indicator of fetal asphyxia. The objective is to develop an experimental lamb model involving the transition from fetal to neonatal life and to examine the effect of fetal asphyxia with cerebral hypoxic ischemia on early postnatal cerebral glucose metabolism. Fetal asphyxia was induced by total umbilical cord occlusion in eight near‐term fetal lambs (134–138 days) with the ewe under isoflurane‐opiate anesthesia. The mean occlusion time until cardiac arrest was 14.5 (4.2) min (SD). Lambs were immediately delivered and standardized resuscitation was instituted after 2 min asystole. At 4 hr postnatal age, [18‐F]Fluoro‐2‐deoxy‐glucose (18‐FDG) was injected intravenously in eight asphyxiated lambs and in eight controls. Cerebral glucose metabolism was examined by positron emission tomography (PET). As a result the mean arterial blood pressure, acid‐base values, blood glucose and serum lactate at 4 hr postnatal age did not differ significantly between lambs subjected to umbilical cord occlusion and controls. EEG was abnormal in all lambs subjected to cord occlusion and normal in the controls at 4 hr postnatal age. Global cerebral metabolic rate (CMRgl) as determined by PET was significantly lower in lambs subjected to cord occlusion mean/median (SD) 22.2/19.6 (8.4) μmol/min/100 g) than in controls mean/median (SD) 37.8/35.9 (6.1); P < 0.01). Global CMRgl is significantly reduced in newborn lambs 4 hr after fetal asphyxia induced by umbilical cord occlusion. A reduction in CMRgl is an early indicator of global hypoxic cerebral ischemia.

Apgar score predicts short-term outcome in infants born at 25 gestational weeks

Aim: To identify early predictors of outcome in infants born at 25 gestational weeks.

Neonatal outcome of extremely small low birthweight liveborn infants below 901 g in a Swedish population

ABSTRACT. In a regional population of 32120 liveborn newborn infants 65 (0.2%) had a birthweight ≤900 g (extremely small low birthweight = ESLBW) with mean gestational age 26.4 (range 22–31) completed weeks of gestation. The total 0–1 year survival rate was 48%. For the 42 infants treated in the Level III regional neonatal intensive care unit (NICU) the 0–1 year survival rate was 55% versus 34% for 23 infants not transferred to the Level III unit. In the ESLBW infants treated in the regional NICU the major complications were respiratory disorders requiring artificial ventilation (73%), bronchopulmonary dysplasia (26%), intracranial haemorrhages (40%), symptomatic persistent ductus arteriosus (36%) and sepsis (14%), persistent retinopathy of prematurity (8%). Duration of NICU treatment was 51 days (range 10–95) for survivors. Mode of delivery and rate of perinatal complications did not differ between survivors and non‐survivors. Previous legal abortion occurred in 24%, fertility problems in 29% and 21% of the mothers, were immigrants. Otherwise no significant abnormalities were found in maternal or socioeconomic conditions. Factors deciding neonatal outcome in the tiniest babies seem to be a combination of prenatal circumstances and neonatal minute fine care procedures.