Division of Neonatology, Sidra Medicine, Doha, Qatar.
Weill Cornell Medicine, Doha, Qatar.
Pediatr Res. 2024 Aug;96(3):595-603. doi: 10.1038/s41390-022-02427-8. Epub 2023 Jan 2.
Transitional circulation is normally transient after birth but can vary markedly between infants. It is actually in a state of transition between fetal (in utero) and neonatal (postnatal) circulation. In the absence of definitive clinical trials, information from applied physiological studies can be used to facilitate clinical decision making in the presence of hemodynamic compromise. This review summarizes the peculiar physiological features of the circulation as it transitions from one phenotype into another in term and preterm infants. The common causes of hemodynamic compromise during transition, intact umbilical cord resuscitation, and advanced hemodynamic monitoring are discussed. IMPACT: Transitional circulation can vary markedly between infants. There are alterations in preload, contractility, and afterload during the transition of circulation after birth in term and preterm infants. Hemodynamic monitoring tools and technology during neonatal transition and utilization of bedside echocardiography during the neonatal transition are increasingly recognized. Understanding the cardiovascular physiology of transition can help clinicians in making better decisions while managing infants with hemodynamic compromise. The objective assessment of cardio-respiratory transition and understanding of physiology in normal and disease states have the potential of improving short- and long-term health outcomes.
过渡循环通常在出生后是短暂的，但在婴儿之间可能有很大的差异。它实际上处于胎儿（宫内）和新生儿（产后）循环之间的过渡状态。在没有明确的临床试验的情况下，可以利用应用生理学研究的信息，在存在血液动力学障碍的情况下，为临床决策提供便利。这篇综述总结了在足月和早产婴儿中，循环从一种表型过渡到另一种表型时的特殊生理特征。讨论了过渡期间常见的血液动力学障碍的原因、完整的脐带复苏和先进的血液动力学监测。
过渡循环在婴儿之间可能有很大的差异。在足月和早产婴儿出生后的循环过渡过程中，前负荷、收缩力和后负荷都会发生变化。新生儿过渡期间的血液动力学监测工具和技术以及床边超声心动图在新生儿过渡期间的应用越来越受到认可。了解过渡期间的心血管生理学可以帮助临床医生在处理血液动力学障碍的婴儿时做出更好的决策。对心肺过渡的客观评估以及对正常和疾病状态下生理学的理解，有可能改善短期和长期的健康结果。
