Higher Incidence Of Respiratory Distress Syndrome Research Articles

Association between Thyroid Function and Respiratory Distress Syndrome in Preterm Infants.

Thyroid hormones are known to influence the production and secretion of pulmonary surfactant. The objective of this study was to explore the relationship between respiratory distress syndrome (RDS) and thyroid hormones. This was a retrospective study of preterm infants at 24-33 weeks gestational age from April 2017 to February 2019. T3, free T4 (fT4), and thyroid-stimulating hormone (TSH) were measured 1, 3, and 6 weeks after birth. Multivariate logistic regression analyses were performed to determine the relationship between RDS and TSH. A total of 146 infants were enrolled. Of these, 60 had RDS, 72 had no RDS, and 14 were excluded. T3 and TSH were lower in the RDS groups (p < 0.05) on the day of birth. Multivariate logistic regression analysis indicated that lower serum TSH levels immediately after birth were associated with a higher incidence of RDS (OR, 0.89; 95% CI, 0.81-0.97). The TSH level was associated with the incidence of RDS. This suggests that suppression of the hypothalamus-pituitary axis function contributes to RDS, which is the result of surfactant deficiency.

Mode of Delivery and Neonatal Outcomes in Preterm, Small-for-Gestational-Age Newborns

More than 50% of neonates born before 34 weeks of gestation in the United States are delivered by cesarean section (CS). When intrauterine growth restriction is present or the neonate is small for gestational age (SGA), vaginal delivery has been reported to be associated with increased odds of neonatal mortality. Given the increased risk of morbidity and mortality for SGA newborns and the relative impossibility of a conclusive randomized controlled trial, this study was performed to examine the association between route of delivery and neonatal outcomes, particularly neonatal death, intraventricular hemorrhage (IVH), and respiratory distress syndrome (RDS), in a large, diverse cohort of preterm SGA newborns. Data on 1,025,903 singleton live births from 1995 to 2003 were obtained from a data set linking birth certificate and hospital discharge data in New York City. The study population included only women delivering vertex-presenting, singleton neonates between 25 and 34 6/7 weeks of gestation (n = 31,135). Of 23,144 neonates meeting the inclusion criteria, 2885 met the definition for SGA at delivery. Small for gestational age was used as a surrogate for intrauterine growth restriction. Because of the wide range of gestational ages, a subanalysis was done for those with a gestational age less than 30 weeks (n = 359). Another study population included all operative deliveries (n = 2927). Main outcomes included neonatal death before discharge, neonatal RDS, sepsis, IVH, seizure, subdural hemorrhage, or 5-minute Apgar score less than 7. Maternal characteristics included age, parity, race and ethnicity, level of education, insurance status, and prepregnancy weight. Covariates included diabetes, hypertension, and gestational age of delivery. Of the 2885 neonates, 1214 (42.1%) were delivered vaginally, and 1671 (57.9%) were delivered by CS. All maternal and pregnancy characteristics differed significantly between the 2 groups (P < 0.05). Women who underwent CS were older, heavier, better educated, more likely to be white, and more often had diabetes or hypertension. The rate of CS rose in SGA newborns born at 34 weeks of gestation or less during the course of the study (1995–2003; 50% and 61% in 1995 and 2003). Neonates delivered by CS had a higher incidence of RDS and 5-minute Apgar scores of less than 7 compared with those delivered vaginally (odds ratio [OR], 1.49; 95% confidence interval [CI], 1.25–1.76; and OR 1.42; 95% CI, 1.07–1.87, respectively). After adjustment for maternal age, race, parity, education, insurance status, prepregnancy weight, diabetes, hypertension, and gestational age at delivery, CS was still associated with increased odds of RDS compared with vaginal delivery (adjusted OR, 1.32; 95% CI, 1.07–1.63) and tended to be associated with slightly elevated risks for all outcomes except IVH and neonatal death. When forceps and vacuum deliveries were included in the analysis, results were not altered significantly. The fact that CS is associated with more RDS indicates that CS is not necessarily beneficial to SGA preterm neonates. The known risks and costs of CS might be justified if CS improves neonatal outcomes. However, these results show that CS compared with vaginal delivery was not associated with any statistically significant benefit for preterm SGA neonates. Further research is necessary to evaluate the effects of the rising CS rate in preterm SGA neonates. As with full-term newborns, vaginal delivery offers neonates an early respiratory advantage compared with CS.

Pregnancy-induced hypertension and reduced intraventricular hemorrhage in preterm infants

Increasing evidence suggests that the incidence of periventricular intraventricular hemorrhage (PV-IVH) is lower in infants born to mothers with pregnancy-induced hypertension (PIH). The mechanism or mechanisms accounting for this reduction remain unclear but may be related to PIH itself, medications used to treat the mother (e.g., magnesium sulfate), or to obstetrical management. In this retrospective analysis, we determined the incidence of PV-IVH in singleton preterm infants weighing less than 1,500 gm born to mothers with PIH who were also administered magnesium sulfate. Between January 1988 and December 1994, 254 singleton infants born to mothers with PIH and 1,083 born to mothers without PIH were studied. PV-IVH developed in 360 (26.9%) of the 1,337 infants; 977 (74.1%) infants did not exhibit PV-IVH. The incidence of total as well as severe PV-IVH was lower in infants born to mothers with PIH than in those without PIH [i.e., 16% vs 30% (total) and 8.2% vs 14.5% (severe), P < .001] with an odds ratio (OR) estimate of 0.43 [95% confidence interval (CI) 0.30, 0.61]. Infants born to mothers with PIH weighed more, (1,152 ± 250 gm vs 1,058 ± 283 gm, P < .001) and were more mature (30.1 ± 2.9 vs 27.7 ± 31 weeks, P < .001) than infants born to mothers without PIH. These infants were also less likely to be exposed to labor (57% vs 93 %), to be delivered by cesarean section (81 % vs 35%), and to require intubation (49% vs 58%), but more likely to exhibit respiratory distress syndrome (RDS) (47% vs 38%, P < .01). By logistic regression analysis, after seven variables (i.e., PIH, gestational age, and birthweight, both modeled as cubic polynomials; labor; intubation; RDS; and race) were included in the analytic model, PIH remained a significant predictor of IVH: P = .006, OR = 0.54 (95% CI 0.349, 0.847). These data indicate a significantly lower incidence of PV-IVH of approximately 50% in infants born to mothers with PIH as compared with the incidence in infants born to mothers without PIH, despite their higher incidence of RDS. The reduction in PV-IVH may be directly related to the PIH; however, the independent role of antenatal magnesium sulfate administration requires further study.

Intraamniotic triidothyronine instillation for prevention of respiratory distress syndrome in pregnancies complicated by hypertension.

Respiratory distress syndrome (RDS) is the main cause of death among premature newborn infants [21]. Despite recent improvements in treatment by neonatal intensive care and respiratory assistance, mortality from RDS remains high [20]. Inadequate pulmonary surfactant is thought to be a primary factor leading to the development of RDS [2]· LIGGINS [12] was the first to observe an accelerated lung maturity of fetal lambs treated in utero with glucocorticoids. LIGGINS and HOWIE [14] first reported the beneficial effect of the maternal administration of antepartum glucocorticoid on the incidence of RDS in premature infants. This has since been confirmed by others [3,5,8,18]. However, attention must be drawn to the possibility of an adverse effect of corticosteroid treatment in cases with hypertensionedema-proteinuria syndromes. In this group a significantly higher fetal death rate was observed under betamethasone therapy [13]. Studies indicating a high incidence of RDS in neonatal hypothyroidism [25] suggest the possibility that thyroid hormones may play an important role on fetal lung maturation. Several animal studies have suggested an important influence of thyroid hormones on acceleration of lung maturation and enhancement of surfactant production [22,27]. Curriculum vitae

An Analysis of the Factors Associated with Respiratory Distress Syndrome in Premature Infants Whose Mothers Had Been Given Dexamethasone Therapy

Summary The incidence of respiratory distress syndrome (RDS) in 259 premature infants whose 218 mothers had received antepartum dexamethasone therapy was 8·9 per cent. The main characteristics of those infants who developed RDS were a shorter gestational age and a lower Apgar score at delivery: all were delivered before 35 weeks gestation, and those with Apgar scores below 7 had a significantly higher incidence of RDS. The incidence of RDS in vaginal breech deliveries (15·4 per cent), Caesarean sections (14·6 per cent), and multiple births (16·0 per cent) was higher than in vaginal vertex deliveries (6·8 per cent), and in singletons (6·0 per cent). The use of isoxsuprine and the length of time membranes were ruptured before delivery were unrelated to the incidence of RDS. The results of this study suggest that while maternal glucocorticoid administration is an important ancillary to the prevention of RDS in premature infants it cannot substitute for optimal delivery conditions.

Serum prolactin and respiratory distress syndrome in the newborn.

Prolactin levels were measured in cord blood by radioimmunoassay in 57 premature infants between 26 and 36 weeks of gestation. The level of prolactin was in the range of 20 to 600 ng/ml. Twenty-three of the infants subsequently developed respiratory distress syndrome (RDS). The mean cord prolactin in the infants with RDS was 140 +/- 30.7 ng/ml, whereas in the healthy infants it was 276.4 +/- 26.4 ng/ml. Cord prolactin levels less than 140 ng/ml were associated with a high incidence of RDS: of 25 infants with prolactin levels of less than 140 ng/ml, 19(76%) had RDS. Of the 34 healthy infants, 28(82%) had prolactin levels above 140 ng/ml. The highest levels (500 ng/ml) or prolactin in the group of infants with RDS were in two infants of diabetic mothers. The data suggest that prolactin might have a role in lung maturation in the human fetus.