Meyer Michael P, Nevill Elizabeth
Neonatal Unit, KidzFirst, Middlemore Hospital, Auckland 2025, New Zealand.
Department of Paediatrics, University of Auckland, Auckland 2025, New Zealand.
Children (Basel). 2021 Apr 26;8(5):336. doi: 10.3390/children8050336.
Major physiologic changes occur during the transition after birth. For preterm infants, current understanding favours allowing the initial changes to occur prior to cord clamping. Amongst other improved outcomes, systematic reviews have indicated a significant reduction in neonatal blood transfusions following delayed cord clamping. This may be due to a placental transfusion, facilitated by the onset of respiration. If breathing is compromised, placental transfusion may be reduced, resulting in a greater red cell transfusion rate. We designed a randomised trial to investigate whether assisting respiration in this high-risk group of babies would decrease blood transfusion and improve outcomes. The Assisted Breathing before Cord Clamping (ABC) study is a single-centre randomised controlled trial. Preterm infants < 31 weeks that have not established regular breathing before 15 s are randomised to a standard or intervention group. The intervention is intermittent positive pressure ventilation via T piece for 30 s, whilst standard management consists of 30 s of positioning and gentle stimulation. The cord is clamped at 50 s in both groups. The primary outcome is the proportion of infants in each group receiving blood transfusion during the neonatal admission. Secondary outcomes include requirement for resuscitation, the assessment of circulatory status and neonatal outcomes.
出生后的过渡阶段会发生重大的生理变化。对于早产儿,目前的认识倾向于在脐带夹闭前让初始变化自然发生。在其他改善的结果中,系统评价表明延迟脐带夹闭后新生儿输血显著减少。这可能是由于呼吸开始促进了胎盘输血。如果呼吸受到影响,胎盘输血可能会减少,导致更高的红细胞输血率。我们设计了一项随机试验,以研究在这一高危婴儿群体中辅助呼吸是否会减少输血并改善结局。脐带夹闭前辅助呼吸(ABC)研究是一项单中心随机对照试验。胎龄<31周且在15秒前未建立规律呼吸的早产儿被随机分为标准组或干预组。干预措施是通过T形管进行30秒的间歇正压通气,而标准管理包括30秒的体位调整和轻柔刺激。两组均在50秒时夹闭脐带。主要结局是每组在新生儿住院期间接受输血的婴儿比例。次要结局包括复苏需求、循环状态评估和新生儿结局。