Small for gestational age at preterm birth identifies adverse neonatal outcomes more reliably than antenatal suspicion of fetal growth restriction.

BACKGROUND: Fetal growth restriction (FGR) is an important reason for premature delivery and a leading cause of perinatal morbidity and mortality. We aimed to evaluate whether classification as small for gestational age (SGA; <10th centile) at birth or antenatal suspicion of FGR was more strongly associated with neonatal morbidity and mortality in preterm infants. METHODS: A retrospective audit of infants born between 24 + 0 and 32 + 6 weeks of gestation from 2012-2019 and admitted to the Neonatal Unit at Mercy Hospital for Women (MHW). Infants were categorized according to whether FGR was listed as an antenatal complication in the medical records and whether they were SGA (<10th centile on Fenton chart) or appropriate for gestational age (AGA) at birth, and comparisons for neonatal outcomes were made. RESULTS: 371/2126 preterm infants (17.5%) had antenatal suspicion of FGR, and 166 (7.8%) were SGA at birth. No differences in any neonatal outcomes were found between infants with or without suspected FGR, except decreased intraventricular hemorrhage (IVH) in the FGR group. SGA classification was associated with increased rates of all morbidities other than IVH, including bronchopulmonary dysplasia, retinopathy of prematurity, and necrotizing enterocolitis, compared with the AGA group. Death was significantly higher in the SGA group (7.2%) compared with the AGA group (3.5%). CONCLUSION: SGA by Fenton chart more reliably identified neonates at risk of adverse neonatal outcomes than antenatal suspicion of FGR, suggesting it is a reasonable clinical proxy. This most likely reflects the much lower tenth centile weight cutoffs on the Fenton charts compared to in-utero charts used antenatally to diagnose FGR based on ultrasound estimated fetal weight. SGA classification by Fenton approximately equates to <3rd centile on in-utero charts at our institution, therefore identifying the most severe FGR cases.

The severe epilepsy syndromes of infancy: A population-based study.

OBJECTIVE: To study the epilepsy syndromes among the severe epilepsies of infancy and assess their incidence, etiologies, and outcomes. METHODS: A population-based cohort study was undertaken of severe epilepsies with onset before age 18 months in Victoria, Australia. Two epileptologists reviewed clinical features, seizure videos, and electroencephalograms to diagnose International League Against Epilepsy epilepsy syndromes. Incidence, etiologies, and outcomes at age 2 years were determined. RESULTS: Seventy-three of 114 (64%) infants fulfilled diagnostic criteria for epilepsy syndromes at presentation, and 16 (14%) had "variants" of epilepsy syndromes in which there was one missing or different feature, or where all classical features had not yet emerged. West syndrome (WS) and "WS-like" epilepsy (infantile spasms without hypsarrhythmia or modified hypsarrhythmia) were the most common syndromes, with a combined incidence of 32.7/100 000 live births/year. The incidence of epilepsy of infancy with migrating focal seizures (EIMFS) was 4.5/100 000 and of early infantile epileptic encephalopathy (EIEE) was 3.6/100 000. Structural etiologies were common in "WS-like" epilepsy (100%), unifocal epilepsy (83%), and WS (39%), whereas single gene disorders predominated in EIMFS, EIEE, and Dravet syndrome. Eighteen (16%) infants died before age 2 years. Development was delayed or borderline in 85 of 96 (89%) survivors, being severe-profound in 40 of 96 (42%). All infants with EIEE or EIMFS had severe-profound delay or were deceased, but only 19 of 64 (30%) infants with WS, "WS-like," or "unifocal epilepsy" had severe-profound delay, and only two of 64 (3%) were deceased. SIGNIFICANCE: Three quarters of severe epilepsies of infancy could be assigned an epilepsy syndrome or "variant syndrome" at presentation. In this era of genomic testing and advanced brain imaging, diagnosing epilepsy syndromes at presentation remains clinically useful for guiding etiologic investigation, initial treatment, and prognostication.

Cerebral blood flow velocities and cerebrovascular resistance in normal-term neonates in the first 72 hours.

AIM: To determine the range of cerebral blood flow velocities (CBFVs) and Doppler indices of cerebrovascular resistance in normal-term neonates as a baseline for a study of hypoxic-ischaemic encephalopathy. METHODS: The CBFVs, resistive index (RI) and pulsatility index (PI) were measured in the anterior and middle cerebral arteries (ACA and MCA) of 38 normal neonates. RESULTS: The mean peak systolic, end diastolic and time-averaged velocities (PSV, EDV and TAV) were 36.3 ± 6.6, 12.4 ± 3.9 and 22.0 ± 4.0 cm/s (ACA) and 41.4 ± 13.2, 13.0 ± 5.5 and 25.8 ± 7.9 cm/s (MCA), respectively. All CBFVs in the ACA correlated with gestation; only EDV was correlated to post-natal age. The RI in the ACA (0.67 ± 0.06) and MCA (0.68 ± 0.07) were correlated (r = 0.72, P < 0.001); RI correlated to post-natal age. Two infants with RI < 0.55 were both fed within 25 mins of the study; RI correlated with post-prandial time (dichotomous, pivot 25 min). The mean PI was 1.11 ± 0.18 (ACA) and 1.17 ± 0.23 (MCA). Correlations were observed with post-natal age and post-prandial time (dichotomous). The average angle of insonation was greater in the ACA than in the MCA (median of 5° vs. 18°). CONCLUSIONS: Results corresponded with previous published studies. No correlation was observed between Doppler indices and gestation as component velocities all increase with advancing gestation. Less variation and smaller standard deviation of CBFV's was associated with a smaller angle of insonation. Low RIs (<0.55), without a pathological cause, warrants further study.

Docosahexaenoic Acid and Bronchopulmonary Dysplasia in Preterm Infants.

BACKGROUND: Studies in animals and in humans have suggested that docosahexaenoic acid (DHA), an n-3 long-chain polyunsaturated fatty acid, might reduce the risk of bronchopulmonary dysplasia, but appropriately designed trials are lacking. METHODS: We randomly assigned 1273 infants born before 29 weeks of gestation (stratified according to sex, gestational age [<27 weeks or 27 to <29 weeks], and center) within 3 days after their first enteral feeding to receive either an enteral emulsion providing DHA at a dose of 60 mg per kilogram of body weight per day or a control (soy) emulsion without DHA until 36 weeks of postmenstrual age. The primary outcome was bronchopulmonary dysplasia, defined on a physiological basis (with the use of oxygen-saturation monitoring in selected infants), at 36 weeks of postmenstrual age or discharge home, whichever occurred first. RESULTS: A total of 1205 infants survived to the primary outcome assessment. Of the 592 infants assigned to the DHA group, 291 (49.1% by multiple imputation) were classified as having physiological bronchopulmonary dysplasia, as compared with 269 (43.9%) of the 613 infants assigned to the control group (relative risk adjusted for randomization strata, 1.13; 95% confidence interval [CI], 1.02 to 1.25; P=0.02). The composite outcome of physiological bronchopulmonary dysplasia or death before 36 weeks of postmenstrual age occurred in 52.3% of the infants in the DHA group and in 46.4% of the infants in the control group (adjusted relative risk, 1.11; 95% CI, 1.00 to 1.23; P=0.045). There were no significant differences between the two groups in the rates of death or any other neonatal illnesses. Bronchopulmonary dysplasia based on a clinical definition occurred in 53.2% of the infants in the DHA group and in 49.7% of the infants in the control group (P=0.06). CONCLUSIONS: Enteral DHA supplementation at a dose of 60 mg per kilogram per day did not result in a lower risk of physiological bronchopulmonary dysplasia than a control emulsion among preterm infants born before 29 weeks of gestation and may have resulted in a greater risk. (Funded by the Australian National Health and Medical Research Council and others; Australian New Zealand Clinical Trials Registry number, ACTRN12612000503820 .).

Accuracy of a Weight-Based Formula for Neonatal Gastric Tube Insertion Length.

BACKGROUND: Gastric tubes are used in nurseries on a daily basis. Various methods of estimating gastric tube length for insertion using anatomical landmarks are used to assist correct placement. Sometimes, however, they can be up to 55% inaccurate. In 2012, we published a weight-based formula to estimate gastric tube length for insertion. PURPOSE: This study reviews the rates of correct gastric tube placement, as confirmed by radiography, after the incorporation of this weight-based formula into bedside practice. METHODS: A 6-month prospective study was performed in a tertiary neonatal intensive care unit. The formula estimating gastric tube length for insertion had been derived in an earlier study. This was incorporated into the hospital's policies and procedures guideline for the insertion of gastric tubes. Neonates with gastric tubes who required radiography for clinical reasons were included. The infant's weight and the type (orogastric or nasogastric) and length of tube were documented. A single radiologist assessed the tube position to be high, borderline, correct, or long. RESULTS: A total of 195 chest radiographs were obtained. Correct tube position was found in 84% of instances. This was a statistically and clinically significant improvement. IMPLICATIONS FOR PRACTICE: Implementation of a simple weight-based estimate for gastric tube length improves correct position rates. IMPLICATIONS FOR RESEARCH: Further studies comparing accuracy of length/height and weight-based estimations for gastric tube insertion lengths in very preterm and extremely preterm infants are needed.

Comparison of the pharyngeal pressure provided by two heated, humidified high-flow nasal cannulae devices in premature infants.

AIMS: This study aims to determine if there is a difference in the pharyngeal pressure, measured as a surrogate for continuous positive distending airway pressure, delivered to premature infants between two commonly used heated, humidified high-flow nasal cannulae (HHHFNC) devices: Fisher & Paykel Healthcare HHHFNC and Vapotherm 2000i. METHODS: Pharyngeal pressure measurements were taken from stable premature infants receiving HHHFNC for respiratory support. Flow rates of 2-8 L/min were studied. RESULTS: Nine infants had pharyngeal pressure measurements recorded with both HHHFNC devices at flow rates of 2-8 L/min. There was no difference in pharyngeal pressures recorded between devices at flow rates of 2-6 L/min; measured pressure was linearly associated with flow (R(2) = 0.9). At flow rates of 7 L/min, Vapotherm delivered a mean (standard deviation) pharyngeal pressure of 4.7 (2.2) cmH2 O compared with 4.23 (2.2) cmH2 O by the Fisher & Paykel device (P = 0.04). At a flow of 8 L/min, the mean pharyngeal pressure via Vapotherm was 4.9 (2.2) cmH2 O compared with 4.1 (2.3) cmH2 O with the Fisher & Paykel device (P = 0.05). CONCLUSIONS: Both HHHFNC delivered similar pharyngeal pressures at flow rates of 2-6 L/min. The pressure limiter valve of the Fisher & Paykel device attenuated the pharyngeal pressures at flows of 7 and 8 L/min. Vapotherm trended towards higher delivered pharyngeal pressure at flow rates 7 and 8 L/min, but the clinical significance of the difference remains unclear.

A randomized controlled trial to compare heated humidified high-flow nasal cannulae with nasal continuous positive airway pressure postextubation in premature infants.

OBJECTIVE: To determine whether postextubation respiratory support via heated, humidified, high-flow nasal cannulae (HHHFNC) results in a greater proportion of infants younger than 32 weeks' gestation being successfully extubated after a period of endotracheal positive pressure ventilation compared with conventional nasal continuous positive airway pressure (NCPAP). STUDY DESIGN: We randomly assigned preterm ventilated infants to Vapotherm HHHFNC or NCPAP after extubation. The primary outcome, extubation failure, was defined by prespecified failure criteria in the 7 days after extubation. RESULTS: A total of 132 ventilated infants younger than 32 weeks' gestation were randomized to receive either HHHFNC (n = 67) or NCPAP (n = 65). Extubation failure occurred in 15 (22%) of the HHHFNC group compared with 22 (34%) of the NCPAP group. There was no difference in the number of infants reintubated in the first week. Treatment with HHHFNC reduced the nasal trauma score 3.1 (SD 7.2) versus NCPAP 11.8 (SD 10.7), P < .001. CONCLUSIONS: HHHFNC and NCPAP produced similar rates of extubation failure.

A weight-based formula for the estimation of gastric tube insertion length in newborns.

OBJECTIVE: Safe and effective functioning of nasogastric and orogastric tubes in the neonatal intensive care unit (NICU) is achieved by ensuring their correct placement within the stomach. Insertion length has traditionally been estimated using morphological measures, but studies have indicated that these are frequently inaccurate. This study aimed to evaluate the frequency of correct tube placement and to determine a weight-based formula for estimation of insertion length. STUDY DESIGN: A prospective study was performed over a 6-month period in a tertiary NICU. Infants with gastric tubes who required radiography for clinical reasons were included. The infant's weight and the type and length of tube were documented. A radiologist assessed the tube position to be high, borderline, correct, or long. RESULTS: A total of 218 radiographs of infants weighing 397 to 4131 g were included. Correct tube position was achieved on 74% of occasions. By analyzing data for correct tube positions, formulas were derived to predict tube insertion length in centimeters: orogastric = [3 × weight (kg) + 12] and nasogastric = [3 × weight (kg) + 13]. The formulas correctly predicted 60% of misplaced orogastric tubes and 100% of misplaced nasogastric tubes. CONCLUSION: We propose a novel weight-based formula for estimation of gastric tube insertion length in newborn infants to improve the accuracy of this routine procedure.

The diagnostic value of a single measurement of superior vena cava flow in the first 24 h of life in very preterm infants.

Low superior vena cava (SVC) flow has been associated with intraventricular haemorrhage (IVH) in very preterm infants. We studied the diagnostic value of a single measurement of SVC flow within the first 24 h of life in very preterm infants and its association with occurrence or extension of IVH in a setting of limited availability of neonatal echocardiography. Preterm infants who were born at less than 30 weeks gestation and who had an echocardiogram within 24 h after birth were eligible. Baseline, clinical and ultrasound data were collected. A total of 165 preterm infants were included. Low SVC flow (<41 ml/kg/min) occurred in six infants and was associated with severe IVH and extension of IVH, although this was not significant after adjusting for confounders. The only independently associated variable with low SVC flow was admission temperature (odds ratio 0.27, p = 0.001). A review of SVC flow values shows that these are higher now than initially reported. This study does not show an association of low SVC flow and severe IVH or extension of IVH after adjusting for confounders as a single measurement of SVC flow did not add any diagnostic value in this cohort. Thus, the exact role of SVC flow measurements in the circulatory assessment of preterm infants remains to be elucidated. However, admission temperature may have an effect on systemic blood flow in very preterm infants.

Amniotic fluid lamellar body concentration as a marker of fetal lung maturity at term elective caesarean delivery.

BACKGROUND: Caesarean birth, without prior labour, is associated with an increased risk of neonatal respiratory morbidity among term infants. The concentration of lamellar bodies in amniotic fluid reflects pulmonary surfactant production and release, and is thus used in preterm populations as a marker of fetal lung maturity. Whether amniotic fluid lamellar body concentration (AFLBC) may correlate with risk factors for term respiratory distress has not previously been evaluated. AIMS: To determine the relationship between AFLBC and risk factors for respiratory distress following term caesarean birth. METHODS: The AFLBC of 249 women at the time of term caesarean birth was examined for an association with gestational age, gender, presentation and neonatal respiratory distress requiring special care nursery (SCN) admission. RESULTS: There was a significant increase in AFLBC with gestation. When compared with caesarean deliveries performed during the 37th week of gestation, there was a 50%, 54% and 56% increase in lamellar body concentrations (LBCs) taken during the 38th, 39th and 40th week of gestation respectively (P < 0.05 for all). Female fetuses had a 16% higher LBC than males (P < 0.05). An LBC <100 x 10(9) mL(-1) was associated with increased risk of admission to the SCN with respiratory distress (RR = 5.6; 1.2-26.5, P < 0.05). CONCLUSION: Known risk factors for term respiratory distress are reflected in the AFLBC. A significant relationship exists between AFLBC and respiratory morbidity following term caesarean birth. However, the low prevalence of this condition limits the clinical role of AFLBC as a predictive test for term respiratory morbidity.