Kluckow Martin, Hooper Stuart B
University of Sydney and Royal North Shore Hospital, Sydney, Australia.
The Ritchie Centre, MIMR-PHI Institute for Medical Research, Monash University, Melbourne, Australia.
Semin Fetal Neonatal Med. 2015 Aug;20(4):225-31. doi: 10.1016/j.siny.2015.03.002. Epub 2015 Mar 27.
Immediate clamping and cutting of the umbilical cord at birth has been the accepted standard of care for decades. The physiologic rationale relating umbilical cord clamping (UCC) to the events of the circulatory transition is not considered in arbitrarily recommended cord clamping times. Systematic review of early versus deferred UCC shows significant hemodynamic benefits to the deferred group. Mechanisms for this protective effect are considered in this review. The original concept of a placental transfusion with a volume load and prevention of low cardiac output relies on the physiological end point of the amount of blood transfused. The newer concept of an ordered physiological transition is increasingly supported. This model places aeration of the lungs and an increase in pulmonary blood flow back at the centre of the circulatory transition with timing of UCC being related to establishment of respiration. The need for "physiologically based" UCC is discussed.
几十年来，出生时立即夹紧并剪断脐带一直是公认的护理标准。在任意推荐的脐带夹紧时间中，并未考虑将脐带夹紧（UCC）与循环转变事件相关联的生理原理。对早期与延迟脐带夹紧的系统评价表明，延迟组有显著的血流动力学益处。本综述探讨了这种保护作用的机制。最初关于通过容量负荷进行胎盘输血以及预防低心输出量的概念依赖于输血总量这一生理终点。越来越多的人支持有序生理转变这一新概念。该模型将肺通气和肺血流量增加重新置于循环转变的核心位置，脐带夹紧时间与呼吸建立相关。文中讨论了“基于生理”的脐带夹紧的必要性。
