Active versus restrictive ligation strategy for patent ductus arteriosus - A retrospective two-center study of extremely preterm infants born between 22 + 0 and 25 + 6 weeks of gestational age

BACKGROUND

Patent ductus arteriosus (PDA) in premature infants is associated with adverse clinical outcomes. Mode and timing of treatment are still controversial. Data are limited in the most extremely premature infants <26 weeks of gestational age (GA), where clinical problems are most significant and patients are most vulnerable.

AIMS

To investigate whether different approaches to surgical closure of PDA in two large Swedish centers has an impact on clinical outcomes including mortality in extremely preterm infants born <26 weeks GA.

STUDY DESIGN

Retrospective, two-center, cohort study.

SUBJECTS

Infants born at 22+0-25+6 weeks GA between 2010 and 2016 at Uppsala University Children's Hospital (UUCH; n = 228) and Queen Silvia Children's Hospital Gothenburg (QSCHG; n = 220).

MAIN OUTCOME MEASURES

Survival, bronchopulmonary dysplasia (BPD), and retinopathy of prematurity (ROP).

RESULTS

Surgical closure of PDA was more common and performed earlier at QSCHG (50 % vs 16 %; median age 11 vs 44 days; p < 0.01). Survival was similar in both centres. There was a higher incidence of severe BPD and longer duration of mechanical ventilation at UUCH (p < 0.01). There was a higher incidence of ROP, IVH and sepsis at QSCH (p < 0.05, p < 0.01 and p < 0.01). A sub-group analysis matching all surgically treated infants at QSCHG with infants at UUCH with the same GA showed similar results as the total cohort.

CONCLUSION

Earlier and higher rate of surgical PDA closure in this cohort of extremely preterms born <26 weeks GA did not impact mortality but was associated with lower rates of severe BPD and higher rates of severe ROP.

Fluid management considerations in extremely preterm infants born at 22-24 weeks of gestation

Emerging data regarding the encouraging outcomes of extremely preterm infants from centers taking active approaches to the care of these infants have prompted dialogue regarding optimal medical management. Among the multitude of decisions providers make in caring for extremely premature infants is the prescribing of parenteral fluids. Surprisingly, there are limited data to guide evidenced-based approaches to fluid and electrolyte management in this population. Immaturity of renal function and skin barriers contribute to the impaired capacity of the preterm infant to maintain salt and water homeostasis. This perspective paper highlights developmental physiological properties of the kidney and skin, which the provider needs to understand to provide parenteral fluid therapy. Additionally, we provide recommendations for initial fluid and electrolyte management of the preterm infant based on novel data as well as the published literature.

Early extubation is associated with shorter duration of mechanical ventilation and lower incidence of bronchopulmonary dysplasia

INTRODUCTION

Respiratory care of extremely preterm infants remains a challenge. The majority require invasive mechanical ventilation (MV), which is a contributing factor in developing bronchopulmonary dysplasia (BPD). It is important to keep MV to a minimum but there have been concerns that attempting extubation too early increases the risk for atelectasis, re-intubation, and further lung trauma. The aim of this study was to compare two different approaches to extubation.

METHODS

Single-center, retrospective cohort study including infants born at 22 + 0-25 + 6 weeks during 2005-2009 and 2011-2015, before and after implementing guidelines recommending delayed extubation. Primary outcomes were BPD, duration of MV and length of hospital stay.

RESULTS

Eighty-eight infants in the early era and 102 infants in the late era were included. Infants in the first period were younger at first extubation attempt, and a higher number of infants were extubated within 24 h, 72 h, and one week after birth. The number of infants re-intubated and postnatal age at re-intubation did not differ between the groups. The incidence of severe BPD was 28% in the early period compared to 48% in the later (p < 0.01). Infants in the late period had longer duration of MV (17 vs 27 days, p < 0.01) but similar length of hospital stay (118 vs 123, p = 0.21).

CONCLUSION

After implementing guidelines recommending delayed extubation, the incidence of severe BPD was higher and the duration of MV was longer. This supports the strategy to attempt extubation early even in extremely preterm infants.

Outcomes of a uniformly active approach to infants born at 22-24 weeks of gestation

OBJECTIVE

To determine survival and outcomes in infants born at 22-24 weeks of gestation in a centre with a uniformly active approach to management of extremely preterm infants.

STUDY DESIGN

Single-centre retrospective cohort study including infants born 2006-2015. Short-term morbidities assessed included retinopathy of prematurity, necrotising enterocolitis, patent ductus arteriosus, intraventricular haemorrhage, periventricular malacia and bronchopulmonary dysplasia. Neurodevelopmental outcomes assessed included cerebral palsy, visual impairment, hearing impairment and developmental delay.

RESULTS

Total survival was 64% (143/222), ranging from 52% at 22 weeks to 70% at 24 weeks. Of 133 (93%) children available for follow-up at 2.5 years corrected age, 34% had neurodevelopmental impairment with 11% classified as moderately to severely impaired. Treatment-requiring retinopathy of prematurity, severe bronchopulmonary dysplasia, visual impairment and developmental delay correlated with lower gestational age.

CONCLUSIONS

A uniformly active approach to all extremely preterm infants results in survival rates that are not distinctly different across the gestational ages of 22-24 weeks and more than 50% survival even in infants at 22 weeks. The majority were unimpaired at 2.5 years, suggesting that such an approach does not result in higher rates of long-term adverse neurological outcome.

Reduced rate of treated retinopathy of prematurity after implementing lower oxygen saturation targets

OBJECTIVE

To evaluate an implementation of lower oxygen saturation targets with retinopathy of prematurity (ROP) as primary outcome, in infants at the lowest extreme of prematurity.

STUDY DESIGN

Retrospective cohort including infants born at 22-25 weeks of gestation in 2005-2015 (n = 325), comparing high (87-93%) and low (85-90%) targets; infants transferred early were excluded from the main analysis to avoid bias.

RESULTS

Overall survival was 76% in high saturation era, and 69% in low saturation era (p = .17). Treatment-requiring ROP was less common in low saturation group (14% vs 28%, p < .05) with the most prominent difference in the most immature infants. Including deceased infants in the analysis, necrotizing enterocolitis was more frequent in low saturation era (21% vs 10%, p < .05).

CONCLUSIONS

Implementing lower saturation targets resulted in a halved incidence of treatment-requiring ROP; the most immature infants seem to benefit the most. An association between lower oxygenation and necrotizing enterocolitis cannot be excluded.