Stark Michael J, Hodyl Nicolette A, Andersen Chad C
1] Robinson Research Institute & School of Paediatrics and Reproductive Health, University of Adelaide, South Australia, Australia [2] Department of Neonatology, Women's & Children's Hospital, North Adelaide, South Australia, Australia.
Robinson Research Institute & School of Paediatrics and Reproductive Health, University of Adelaide, South Australia, Australia.
Pediatr Res. 2015 Sep;78(3):310-4. doi: 10.1038/pr.2015.96. Epub 2015 May 18.
The underlying neuro-protective mechanisms of antenatal magnesium sulfate (MgSO(4)) in infants born preterm remain poorly understood. Early neonatal brain injury may be preceded by low cerebral blood flow (CBF) and elevated cerebral fractional tissue oxygen extraction (cFTOE). This study investigated the effect of antenatal MgSO(4) on cerebral oxygen delivery, consumption, and cFTOE in preterm infants.
CBF and tissue oxygenation index were measured, and oxygen delivery, consumption, and cFTOE calculated within 24 h of birth and at 48 and 72 h of life in 36 infants ≤ 30 wk gestation exposed to MgSO(4) and 29 unexposed infants.
Total internal carotid blood flow and cerebral oxygen delivery did not differ between the groups at the three study time-points. Cerebral oxygen consumption and cFTOE were lower in infants exposed to antenatal MgSO(4) (P = 0.012) compared to unexposed infants within 24 h of delivery. This difference was not evident by 48 h of age. Fewer infants in the MgSO(4) group developed P/IVH by 72 h of age (P = 0.03).
Infants exposed to MgSO(4) had similar systemic and cerebral hemodynamics but lower cFTOE compared to nonexposed. These findings suggest reduced cerebral metabolism maybe a component of the neuro-protective actions of antenatal MgSO(4).
产前硫酸镁（MgSO₄）对早产儿的潜在神经保护机制仍知之甚少。早期新生儿脑损伤可能先于脑血流量（CBF）降低和脑部分组织氧摄取（cFTOE）升高。本研究调查了产前MgSO₄对早产儿脑氧输送、消耗和cFTOE的影响。
对36例孕周≤30周且暴露于MgSO₄的婴儿和29例未暴露的婴儿在出生后24小时内以及出生后48小时和72小时测量CBF和组织氧合指数，并计算氧输送、消耗和cFTOE。
在三个研究时间点，两组的颈内动脉总血流量和脑氧输送无差异。与未暴露的婴儿相比，暴露于产前MgSO₄的婴儿在出生后24小时内脑氧消耗和cFTOE较低（P = 0.012）。到48小时龄时，这种差异不明显。MgSO₄组中在72小时龄时发生P/IVH的婴儿较少（P = 0.03）。
与未暴露的婴儿相比，暴露于MgSO₄的婴儿具有相似的全身和脑血流动力学，但cFTOE较低。这些发现表明脑代谢降低可能是产前MgSO₄神经保护作用的一个组成部分。
