Neuroprotective effect of magnesium sulfate in premature infants. Analysis after establishing an antenatal administration protocol in a tertiary care hospital.

INTRODUCTION: In 2016, a protocol was developed in our hospital for the antenatal administration of magnesium sulfate in pregnant women at risk of imminent preterm birth as a method to reduce the risk of cerebral palsy (CP). MATERIAL AND METHODS: We conducted a retrospective observational study in a level IIIC hospital with the primary objective of comparing the incidence of CP before and after the implementation of this protocol. Among the secondary outcomes, we ought to highlight the incidence of cognitive deficits and necrotizing enterocolitis and the mortality in both groups. The sample consisted of preterm newborns delivered before 32 weeks of gestation in 2011-2012 (prior to the implementation of the protocol) and in 2016-2018 (after the implementation of the protocol, whose mothers had received magnesium sulfate for neuroprotection). The clinical and epidemiological characteristics of both groups were comparable. RESULTS: We collected data for a total of 523 patients, 263 and 260 in each group. As regards the primary outcome, we did not find statistically significant differences between groups. We observed a statistically significant reduction in mortality and the risk of severe necrotizing enterocolitis in the group of patients born in the 2016-2018 period and between 26+0 and 27+6 weeks of gestation, whose mothers had received magnesium sulfate. CONCLUSIONS: In our study, the administration of magnesium sulfate to mothers at risk of preterm birth did not decrease the risk of developing CP.

Cost-effectiveness of a cytomegalovirus screening strategy in neonates born after 34 weeks small for gestational age.

INTRODUCTION: Infection by cytomegalovirus (CMV) is one of the most common congenital infections, with a global prevalence of 0.3%-2.4%. In Spain, CMV screening is not performed during pregnancy, but rather in neonates with risk factors, and, in many hospitals, in those born small for gestational age (SGA). Screening is usually performed by measurement of the viral load in urine by polymerase chain reaction (PCR) and/or head ultrasound in search of compatible features. The aim of the study was to assess the yield of the CMV PCR test in urine and head ultrasound examination in asymptomatic neonates born SGA after 34 weeks' gestation. The secondary objective was to assess the cost-effectiveness of this strategy. DESIGN AND METHODS: We conducted an observational and retrospective study between January and December 2019 in a tertiary care hospital. It included neonates delivered after 34 weeks, SGA and without additional risk factors assessed with a CMV PCR test in urine and/or head ultrasound. RESULTS: The sample included 259 patients. It was divided in 2 groups: group 1, patients with a head circumference, weight and length below the 10th percentile (53 patients; 20.5%), and group 2, patients in whom only the weight was below the 10th percentile (206 patients; 79.5%). The incidence of late preterm birth, twin pregnancy, neonatal admission and exposure to illicit drugs during gestation was higher in group 1. A total of 186 urine PCR tests and 223 head ultrasounds were performed overall, and both tests were performed more frequently in group 1 (P=.002). There was only 1 positive CMV PCR test result in the sample (0.54%), corresponding to a patient in group 2 with no abnormal sonographic findings who remained asymptomatic throughout the follow-up. Two head ultrasound examinations yielded abnormal findings, in both cases unrelated to congenital CMV infection. We performed a cost-effectiveness analysis and determined that the cumulative cost of head ultrasound examinations and urine CMV PCR tests in our sample amounted to Є17 000 for the detection of a single asymptomatic positive case. CONCLUSION: In our population, screening for congenital CMV infection in asymptomatic late preterm and term newborns whose only risk factor is SGA does not seem to be cost effective. It would be necessary to expand the sample to other populations.

[Risks factors associated with intra-partum foetal mortality in pre-term infants]. / Factores de riesgo asociados a mortalidad fetal intraparto en recién nacidos pretérmino.

INTRODUCTION: Pre-term delivery is one of the leading causes of foetal and perinatal mortality. However, perinatal risk factors associated with intra-partum foetal death in preterm deliveries have not been well studied. OBJECTIVE: To analyse foetal mortality and perinatal risk factors associated with intra-partum foetal mortality in pregnancies of less than 32 weeks gestational age. MATERIAL AND METHODS: The study included all preterm deliveries between 22 and 31 +1 weeks gestational age (WGA), born in a tertiary-referral hospital, over a period of 7 years (2008-2014). A logistic regression model was used to identify perinatal risk factors associated with intra-partum foetal mortality (foetal malformations and chromosomal abnormalities were excluded). RESULTS: During the study period, the overall foetal mortality was 63.1% (106/168) (≥22 weeks of gestation) occurred in pregnancies of less than 32 WGA. A total of 882 deliveries between 22 and 31+6 weeks of gestation were included for analysis. The rate of foetal mortality was 11.3% (100/882). The rate of intra-partum foetal death was 2.6% (23/882), with 78.2% (18/23) of these cases occurring in hospitalised pregnancies. It was found that Assisted Reproductive Techniques, abnormal foetal ultrasound, no administration of antenatal steroids, lower gestational age, and small for gestational age, were independent risk factors associated with intra-partum foetal mortality. CONCLUSION: This study showed that there is a significant percentage intra-partum foetal mortality in infants between 22 and 31+6 WGA. The analysis of intrapartum mortality and risk factors associated with this mortality is of clinical and epidemiological interest to optimise perinatal care and improve survival of preterm infants.

Survival estimations at the limit of viability.

OBJECTIVE: The purpose of this study was to assess the variability in neonatal survival to discharge from the neonatal unit by using different inclusion criteria. METHODS: An observational and descriptive study was performed between January 2008 and December 2013 which included infants born between 22 weeks and 31 weeks and 6 d of gestation. The rate of survival was calculated using three different inclusion criteria: the total number of preterm births, the number of all preterm live births, and the number of preterm newborns admitted to the neonatal unit. RESULTS: A total of 783 patients met the inclusion criteria. The survival rate for births between 22 and 31 weeks and 6 d of gestation was 72.8% of total births, 82.3% of live births, and 84.0% of all admissions to the neonatal unit. Therefore, we found a significant difference in survival rates according to whether or not foetal mortality (11.6%) and mortality in the delivery room (2.0%) were included. This variation increased with decreasing gestational age: 17,2%, 25%, and 38,4% at 23 weeks gestation. CONCLUSIONS: Late foetal mortality and the mortality in the delivery room affect the survival rates of preterm infants significantly, especially the most immature newborns.

[Stridor in neonates with hypoxic-ischaemic encephalopathy subject to selective cerebral or whole body hypothermia]. / Estridor en neonatos con encefalopatía hipóxico-isquémica sometidos a tratamiento con hipotermia cerebral selectiva o corporal total.

INTRODUCTION: Hypothermia treatment has improved the prognosis of asphyxiated neonates. Widely used, it has demonstrated to be safe without severe side effects. The aim of this article is to review the incidence of stridor amongst asphyxiated newborns treated with hypothermia in our unit. METHODS: Retrospective chart review of our patients. RESULTS: Stridor was presented in 7/75 (9.3%) of patients during hypothermia. Three received whole body hypothermia, 3 selective cerebral, and in one case both techniques were used. All cases required increased respiratory support. CONCLUSIONS: Different mechanisms may be responsible for the appearance of stridor in patients with hypoxic-ischaemic encephalopathy (HIE). In our series the incidence of stridor was similar for the two hypothermia devices. To better understand these possible side effects of hypothermia, further prospective studies (which should include laryngoscopy) are needed.