Characteristics and outcomes of preterm neonates according to number of doses of surfactant received

Risk factors for the time to development of retinopathy of prematurity in premature infants in Iran: a machine learning approach

BACKGROUND

Retinopathy of prematurity (ROP), is a preventable leading cause of blindness in infants and is a condition in which the immature retina experiences abnormal blood vessel growth. The development of ROP is multifactorial; nevertheless, the risk factors are controversial. This study aimed to identify risk factors of time to development of ROP in Iran.

METHODS

This historical cohort study utilized data from the hospital records of all newborns referred to the ROP department of Farabi Hospital (from 2017 to 2021) and the NICU records of infants referred from Mahdieh Hospital to Farabi Hospital. Preterm infants with birth weight (BW) ≤ 2000 g or gestational age (GA) < 34 wk, as well as selected infants with an unstable clinical course, as determined by their pediatricians or neonatologists, with BW > 2000 g or GA ≥ 34 wk. The outcome variable was the time to development of ROP (in weeks). Random survival forest was used to analyze the data.

RESULTS

A total of 338 cases, including 676 eyes, were evaluated. The mean GA and BW of the study group were 31.59 ± 2.39 weeks and 1656.72 ± 453.80 g, respectively. According to the criteria of minimal depth and variable importance, the most significant predictors of the time to development of ROP were duration of ventilation, GA, duration of oxygen supplementation, bilirubin levels, duration of antibiotic administration, duration of Total Parenteral Nutrition (TPN), mother age, birth order, number of surfactant administration, and on time screening. The concordance index for predicting survival of the fitted model was 0.878.

CONCLUSION

Our findings indicated that the duration of ventilation, GA, duration of oxygen supplementation, bilirubin levels, duration of antibiotic administration, duration of TPN, mother age, birth order, number of surfactant administrations, and on time screening are potential risk factors of prognosis of ROP. The associations between identified risk factors were mostly nonlinear. Therefore, it is recommended to consider the nature of these relationships in managing treatment and designing early interventions.

Early-onset neonatal sepsis as a risk factor for peri-intraventricular hemorrhage in premature infants

OBJECTIVE

To assess early-onset sepsis as a risk factor of peri-intraventricular hemorrhage in premature infants born at less than or equal to 34 weeks' gestation and admitted to a neonatal intensive care unit (NICU).

METHODS

This retrospective cohort study included premature patients born at less than or equal to 34 weeks' gestation who were admitted to the NICU of a tertiary hospital in southern Brazil, and born from January 2017 to July 2021. Data were collected from patients' medical records. Early-onset sepsis was measured according to the presence or absence of diagnosis within the first 72 hours of life, whereas the outcome, peri-intraventricular hemorrhage, was described as the presence or absence of hemorrhage, regardless of its grade.

RESULTS

Hazard ratios were calculated using Cox regression models. A total of 487 patients were included in the study, of which 169 (34.7%) had some degree of peri-intraventricular hemorrhage. Early-onset sepsis was present in 41.6% of the cases of peri-intraventricular hemorrhage, which revealed a significant association between these variables, with increased risk of the outcome in the presence of sepsis. In the final multivariate model, the hazard ratio for early-onset sepsis was 1.52 (95% confidence interval 1.01-2.27).

CONCLUSION

Early-onset sepsis and the use of surfactants showed to increase the occurrence of the outcome in premature children born at less than or equal to 34 weeks' gestation. Meanwhile, factors such as antenatal corticosteroids and gestational age closer to 34 weeks' gestations were found to reduce the risk of peri-intraventricular hemorrhage.

Who Needs a Second Dose of Exogenous Surfactant?

OBJECTIVE

To identify prenatal and postnatal risk factors associated with surfactant redosing.

STUDY DESIGN

Retrospective, single-regional center study including all infants born from 24 + 0 to 31 + 6 weeks of gestation in the Marche Region, Italy, and admitted to a single level III regional NICU from January 1, 2004, to February 28, 2021. Clinical factors associated with surfactant redosing were identified through logistic regression analysis.

RESULTS

Of 1615 consecutive admissions, 662 infants were treated with exogenous surfactant: 462 (70%) received a single dose and 200 (30%) received more than 1 dose (25.5% two doses and 4.5% three doses). Risk of redosing was higher for infants born to mothers with hypertension in pregnancy (OR 3.95, P < .001), for small for gestational age (SGA) infants (OR 3.93, P < .001) and when the first surfactant dose was 100 mg/kg instead of 200 mg/kg (OR 4.56/4.61, P < .001). Infants with greater GA, delayed first surfactant administration, and milder respiratory distress syndrome had reduced risk of redosing. Infants who required multiple surfactant doses had a higher rate of bronchopulmonary dysplasia and mortality, as well as longer duration of respiratory support than patients that received 1 dose.

CONCLUSIONS

Hypertension in pregnancy and SGA status were found to be statistically and clinically significant predictors of surfactant redosing. Understanding the pathophysiology of these conditions requires further investigation.

Complete blood count parameters as biomarkers of retinopathy of prematurity: a Portuguese multicenter study

PURPOSE

To evaluate complete blood count (CBC) parameters in the first week of life as predictive biomarkers for the development of retinopathy of prematurity (ROP).

METHODS

Multicenter, prospective, observational study of a cohort of preterm infants born with gestational age (GA) < 32 weeks or birth weight < 1500 g in eight Portuguese neonatal intensive care units. All demographic, clinical, and laboratory data from the first week of life were collected. Univariate logistic regression was used to assess risk factors for ROP and then multivariate regression was performed.

RESULTS

A total of 455 infants were included in the study. The median GA was 29.6 weeks, and the median birth weight was 1295 g. One hundred and seventy-two infants (37.8%) developed ROP. Median values of erythrocytes (p < 0.001), hemoglobin (p < 0.001), hematocrit (p < 0.001), mean corpuscular hemoglobin concentration (p < 0.001), lymphocytes (p = 0.035), and platelets (p = 0.003) of the group of infants diagnosed with ROP any stage were lower than those without ROP. Mean corpuscular volume (MCV) (p = 0.044), red blood cell distribution width (RDW) (p < 0.001), erythroblasts (p < 0.001), neutrophils (p = 0.030), neutrophils-lymphocytes ratio (p = 0.028), and basophils (p = 0.003) were higher in the ROP group. Higher values of MCV, erythroblasts, and basophils remained significantly associated with ROP after multivariate regression.

CONCLUSION

In our cohort, the increase in erythroblasts, MCV, and basophils in the first week of life was significantly and independently associated with the development of ROP. These CBC parameters may be early predictive biomarkers for ROP.

Association of socio-economic status and ethnicity with mortality and morbidity of premature infants admitted to neonatal intensive care in South Auckland, New Zealand

AIM

Socio-economic status (SES) and ethnicity have been associated with worse maternal and fetal outcomes. Counties Manukau is a region of New Zealand which has a high portion of the population living in areas of low SES and has a higher population of ethnic minorities (Pacific Islander, Asian and Maaori). To determine whether SES and ethnicity are associated with worse mortality and morbidity in preterm infants in Counties Manukau Hospital, New Zealand.

METHODS

This retrospective cohort study compared the infants of mothers who live in the most deprived neighbourhoods to the infants of mothers who live in the least deprived neighbourhoods. Infants born between 2000 and 2019 were included if <30 weeks gestation or <1500 g and born in hospital. Primary outcome was combined mortality/morbidity.

RESULTS

Univariate analysis showed demographic differences between the SES and ethnic groups, for example maternal age and maternal smoking. Using logistic regression, SES was not associated with worse neonatal outcomes for the most deprived SES (n = 624) compared to least deprived SES (n = 164). Ethnicity (n = 1326) was not associated with worse neonatal outcomes. Gestational age and maternal smoking were associated with neonatal mortality/morbidity; gestational age and antenatal steroids were associated with neonatal mortality. It was notable that the proportion of the study population in the less deprived groups used for the comparisons was relatively low.

CONCLUSIONS

For preterm, in-hospital births in Counties Manukau over a 20-year period, neonatal outcomes were the same regardless of SES or ethnicity.

Poractant alfa versus bovine lipid extract surfactant: prospective comparative effectiveness study

OBJECTIVE

To compare short term respiratory outcomes in preterm infants treated with bovine lipid extract surfactant or poractant alfa.

STUDY DESIGN

Prospective comparative effectiveness cohort study of infants <32 weeks' gestational age requiring surfactant in thirteen centers. Each center provided bovine lipid extract surfactant for a set period of time in the year 2019 and then changed to poractant alfa for the remainder of the year. The primary outcome was total duration of respiratory support.

RESULT

968 infants were included. 494 received bovine lipid extract surfactant and 474 received poractant alfa. No difference was observed in the total duration of respiratory support (mechanical ventilation or non-invasive) (median 38 vs 40.5 days), need to re-dose surfactant, bronchopulmonary dysplasia, survival to discharge, or length of admission.

CONCLUSION

In this pragmatic study, we did not identify any difference in short term outcomes between the groups based on the type of surfactant received.

Safety and efficacy of a novel double-lumen tracheal tube in neonates with RDS: A prospective cohort study

BACKGROUND

The purpose of this study was to assess the safety and efficacy of a new double-lumen tracheal tube for neonates, with a conventional tracheal tube as a control.

METHOD

Newborns with respiratory distress syndrome (RDS) requiring endotracheal intubation admitted to the tertiary neonatal intensive care unit (NICU) of Qujing Maternal and Child Healthcare Hospital in Yunnan Province between March 2021 and May 2022 were enrolled in this prospective cohort study. Outcome indicators related to effectiveness included mainly the number of intubations, duration of ventilation, duration of oxygenation, and length of stay; safety indicators included any clinical adverse effects during and after intubation. Appropriate stratified and subgroup analyses were performed according to the purpose of intubation, gestational age, and whether the drug was administered via endotracheal tube.

RESULT

A total of 101 neonates were included and divided into two groups based on the choice of tracheal tube: the conventional (n = 50) and new (n = 51) tracheal tube groups. There was no statistical difference between the two groups in terms of adverse effects during and after intubation (p > 0.05). In neonates who were mechanically ventilated without endotracheal surfactant therapy or newborns receiving InSurE technique followed by non-invasive ventilation, no significant differences were found between the two groups regarding any of the efficacy indicators (p > 0.05). However, for neonates on invasive mechanical ventilation, the new tracheal tube allowed for a significant reduction in the duration of mechanical ventilation (96.50[74.00, 144.00] vs. 121.00[96.00, 196.50] hours, p = 0.037) and total ventilation (205.71 ± 80.24 vs. 277.56 ± 117.84 h, p = 0.027), when used as a route for endotracheal drug delivery. Further analysis was performed according to gestational age for newborns requiring intratracheal surfactant administration during mechanical ventilation, and the data showed that for preterm infants, the new tracheal tube not only shortened the duration of mechanical ventilation (101.75 ± 39.72 vs. 155.50 ± 51.49 h, p = 0.026) and total ventilation (216.00 ± 81.60 vs. 351.50 ± 113.79 h, p = 0.010), but also demonstrated significant advantages in reducing the duration of oxygen therapy (9.75 ± 6.02 vs. 17.33 ± 8.43 days, p = 0.042); however, there was no statistical difference in efficacy outcomes between the two groups in full-term infants (p > 0.05).

CONCLUSION

The efficacy and safety of this new tracheal tube are promising in neonates with RDS, especially those requiring surfactant administration via a tracheal tube during mechanical ventilation. Given the limitations of this study, however, the clinical feasibility of this catheter needs to be further confirmed in prospective randomized trials with larger sample sizes.

CLINICAL TRIAL REGISTRATION

http://www.chictr.org.cn/showproj.aspx?proj=122073.

Associations of Respiratory Distress Syndrome Severity and Other Factors With Transient Hypothyroxinemia of Prematurity

Aim

This study examined the associations of respiratory distress syndrome (RDS) severity and other factors on thyroid hormone levels in very low birth weight (VLBW) infants.

Methods

The demographic characteristics, clinical course, morbidity, and initial thyroid function test results of VLBW infants diagnosed with RDS between July 2016 and September 2018 were obtained retrospectively. RDS severity was determined according to the requirement for multiple surfactants. Patients were divided into groups without and with hypothyroxinemia, and variables of interest were compared between the two groups.

Results

Our study involved 98 infants meeting the inclusion criteria; the incidence of hypothyroxinemia was 56.1%. Free T4 (fT4) levels were found to be negatively correlated with gestational week (p < 0.001) and birth weight (p < 0.001). The fT4 levels were significantly lower in infants requiring multiple surfactant doses. In infants with hypothyroxinemia, the duration of invasive mechanical ventilation and oxygen treatment was longer and hemodynamically significant patent ductus arteriosus, grade ≥ 3 intraventricular hemorrhage, and moderate to severe bronchopulmonary dysplasia were more common. Multiple pregnancy (odds ratio (OR) = 5.616, 95%; confidence interval (CI): 1.765-17.874) and the duration of invasive mechanical ventilation (OR = 1.05, 95%; CI: 1.005-1.096) were significant risk factors for the development of hypothyroxinemia in logistic regression analysis.

Conclusions

Transient hypothyroxinemia of prematurity is associated with RDS severity and early morbidities of prematurity. In the presence of multiple pregnancy, patients should be followed up more closely due to the possibility of hypothyroxinemia.

Outcome of Very Premature Newborn Receiving an Early Second Dose of Surfactant for Persistent Respiratory Distress Syndrome

Background: Infants presenting respiratory distress syndrome (RDS) not responding to surfactant often receive a second instillation. Few studies evaluated the consequences of this second administration. This study aimed at determining the outcome of infants presenting persistent RDS and receiving an early second dose of surfactant. Methods: Infants below 32 weeks' gestation who received a second dose of 100mg/kg of surfactant within the first 72 h of life, were retrospectively involved in this 42 months' study. They were matched to two controls receiving a single dose of 200mg/Kg based upon gender and gestational age. Results: 52/156 infants receiving two doses (Group 2-doses) were significantly more often SGA [22 (42%) vs. 21 (20%) p = 0.04] and outborn [29 (56%) vs. 13 (12%) p = 0.001]. They had received antenatal corticos teroid therapy less often [26 (50%) vs. 89 (86%) p = 0.001] and presented more severe RDS based upon FiO2 level, oxygenation index and radiography. Group 2-doses survival was lower (65.4% vs. 79.6 % p < 0.1) but surviving infants did not have different morbidity than controls. Discussion: Premature newborn receiving a second dose of surfactant had adverse antenatal characteristics, presented more severe RDS and only partially responded to the first dose. Outcomes of surviving infants who received 2 doses of surfactant were comparable to others.