Absence of PO2 change in fetal brain despite PO2 increase in placenta in response to maternal oxygen challenge
Absence of PO2 change in fetal brain despite PO2 increase in placenta in response to maternal oxygen challenge
复制标题
DOI：
10.1111/1471-0528.12804
复制
发表时间：
2014-12-01
影响因子：
5.8
通讯作者：
Johnstone, E. D.
中科院分区：
文献类型：
--
作者：
Huen, I.;Morris, D. M.;Johnstone, E. D.
磁共振成像允许通过量化磁纵向弛豫时间T-1来无创地观察空气呼吸和氧气呼吸之间Po-2的变化。Po-2的变化与纵向弛豫速率R-1的变化成正比（其中R-1=1/T-1氧-1/T-1空气）。这种反应的知识可以告知临床干预措施，使用母体氧管理产前治疗胎儿生长受限。我们提出了胎儿胎盘单位对母体高氧反应的体内测量方法。设计前瞻性队列。设置大型三级妇产医院。样本9名接受低风险妊娠的妇女方法在成像过程中，将给母亲的空气供应从医疗空气改为非医疗空气，使用周期性重复的磁共振成像序列监测胎盘和胎儿大脑中从21%氧气到医用氧气（100%氧气）和T-1随时间的变化。为了证明该方法可以检测到大脑的反应，大脑的反应，从五个正常的成年志愿者使用类似的成像protocol.Main结果measureChanges在T-1以下oxygen challenge.ResultsNo显着的R-1（P=0.42，配对t检验），观察胎儿大脑。在相同受试者中同时观察到显著的胎盘R-1（P=0.0002，配对t检验）为0.020.01/s（平均值+/- SD）。在大脑中的非怀孕的成年人，一个显着的R-1（P=0.01，配对t-检验）0.005 +/- 0.002/s observed.ConclusionShort-term产妇氧管理不改善胎儿脑氧合，在成人大脑中观察到的反应相反。
ObjectiveMagnetic resonance imaging allows the noninvasive observation of Po-2 changes between air breathing and oxygen breathing through quantification of the magnetic longitudinal relaxation time T-1. Changes in Po-2 are proportional to changes in the longitudinal relaxation rate R-1 (where R-1=1/T-1oxygen-1/T-1air). Knowledge of this response could inform clinical interventions using maternal oxygen administration antenatally to treat fetal growth restriction. We present in vivo measurements of the response of the fetal-placental unit to maternal hyperoxia.DesignProspective cohort.SettingLarge tertiary maternity hospital.SampleNine women undergoing low-risk pregnancy (21-33weeks of gestation) and five nonpregnant adults.MethodsDuring imaging the air supply to mothers was changed from medical air (21% oxygen) to medical oxygen (100% oxygen) and T-1 was monitored over time in both the placenta and fetal brain using a periodically repeated magnetic resonance imaging sequence. To demonstrate that the method could detect a brain response, brain responses from five normal adult volunteers were measured using a similar imaging protocol.Main outcome measureChanges in T-1 following oxygen challenge.ResultsNo significant R-1 (P=0.42, paired t-test) was observed in fetal brains. A significant placental R-1 (P=0.0002, paired t-test) of 0.020.01/s (mean +/- SD) was simultaneously observed in the same participants. In the brains of the nonpregnant adults, a significant R-1 (P=0.01, paired t-test) of 0.005 +/- 0.002/s was observed.ConclusionShort-term maternal oxygen administration does not improve fetal brain oxygenation, in contrast to the response observed in the adult brain.