NIRS监测新生儿缺氧缺血性脑病脑氧合代谢和脑血流量的临？…

目的 观察缺缺血性脑病（ＨＩＥ）的脑氧合代谢和脑血流量变化,早期判定不同程度缺氧缺血性脑病的脑功能状态。方法 采用近红外光谱仪监测２４例ＨＩＥ患儿音乐刺激（ＭＳ）前后脑前额皮质区域氧合血红蛋白（ＨｂＯ２）,还原血红蛋白（Ｈｂ）,总血红蛋白（ｔＨｂ）的变化,并与对照组（３０例）作比较。结果 对照组ＨｂＯ２、Ｈｂ、ｔＨｂ明显上升。ＨＩＥ组：轻度组ＨｂＯ２、ｔＨｂ变化差异无显著性（Ｐ〉０．０５）,Ｈｂ明     

围产期窒息缺氧后脑氧合和脑血液动力学改变及其与心脏损害的关系

围产期窒息缺氧可致新生儿多脏器损伤 ,由于脑损伤可致神经系统后遗症而受到人们的关注。目前认为有多种机制参与脑损伤的病理过程 ,其中脑血液动力学改变与脑氧合密切相关 ,与脑损伤有直接的关系 ,而脑血流和脑血容量又受到心功能和全身血液动力学的影响。现就围产期窒息缺氧后脑氧合状态、脑血液动力学与心脏损害的关系作一综述。一、缺氧后脑氧合及脑血液动力学的变化脑组织的新陈代谢率高 ,其代谢耗能几乎全部依赖于血液供氧。脑循环取决于动脉压、静脉压、颅内压、脑血管的收缩和舒张。脑血管自动调节机制使脑的灌注和血流在一定范围内…     

NIRS监测新生儿缺氧缺血性脑病脑氧合代谢和脑血流量的临床研究

目的 观察缺氧缺血性脑病(HIE)的脑氧合代谢和脑血流量变化,早期判定不同程度缺氧缺血性脑病的脑功能状态.方法 采用近红外光谱仪监测24例HIE患儿音乐刺激(MS)前后脑前额皮质区域氧合血红蛋白(HbO2),还原血红蛋白(Hb),总血红蛋白(tHb)的变化,并与对照组(30例 )作比较.结果 对照组HbO2、Hb、tHb明显上升.HIE组:轻度组HbO 2、tHb变化差异无显著性(P＞0.05),Hb明显增加[MS前:(-0.10±0.24)μmol/L, MS后(0.50±0.33)μmol/L,P＜0.05];中度组HbO2、tHb明显减少[MS前:(0.0 7±0.44)μmol/L,( 0.48±0.43)μmol/L,MS后:(-1.72±0.59)μmol/L,(-0.98±0.55)μmol/L,P＜0.05],Hb明显增加[MS前:(0.41±0.28)μmol/L,MS后:(0.74 ±0.36 μmol/L,P＜0.05],重度组三项均降低[MS前:(0.35±0.80)μmol/L,(0.22 ±0.47)μmol/L,(0.57±0.98)μmol/L,MS后:(-3.24±1.37)μmol/L,(0.15±0.51)μm ol/L,(-3.09±1.39)μmol/L,P＜0.05].将HIE的病情程度与MS前后tHb的变化差值进行直线相关分析,结果二者呈显著负相关关系(r=-0.64, P＜0.001).结论 NI RS可以早期监测HIE的脑功能,判定不同程度缺氧缺血性脑病的脑功能状态.     

基于功能性近红外光谱成像的新生儿缺氧缺血性脑病早期脑功能网络特征题录

目的探讨功能性近红外光谱成像(functional near-infrared spectroscopy, fNIRS)对新生儿缺氧缺血性脑病(hypoxic-ischemic encephalopathy, HIE)的脑功能评估作用。方法本研究为病例对照研究, 选择2023年3月至2024年8月入住复旦大学附属儿科医院新生儿诊疗中心, 并完成fNIRS检测的15例中重度HIE患儿为HIE组, 以及同期完成fNIRS检测的15例无神经系统疾病的足月儿作为对照组。基于静息态fNIRS数据, 进行脑功能连接网络构建并分析其拓扑特征。采用独立样本t检验、Mann-WhitneyU检验、方差分析及χ2检验进行统计学分析。结果 HIE组与对照组相比, 全脑功能连接强度下降[0.15(0.05～0.26)与0.24(0.13～0.35), Z=-7.66, P<0.001]。全局网络属性方面, 2组新生儿小世界指数均大于1, 组间差异无统计学意义(1.17±0.05与1.14±0.05, t=2.02, P=0.050);HIE组的最短路径长度(6.22±0.52与13.74±0.49, t=48.18)、全局效率(0.26±0.04与0.30±0.05, t=2.50)和归一化最短路径(1.50±0.07与1.62±0.22, t=2.43)较对照组均下降(P值均<0.05);2组的聚类系数和局部效率差异均无统计学意义(P值均>0.05)。局部网络属性方面, HIE组左半球(0.30±0.06与0.35±0.05, t=2.47)和右半球(0.30 ±0.06与0.37±0.06, t=2.68)的节点效率均显著小于对照组的对应半球(P值均>0.05);同一组别中左右半球节点效率差异均无统计学意义(P值均>0.05)。结论 fNIRS能够评估HIE脑功能特征, 有助于HIE早期脑功能损伤的评估。     

新生儿缺氧的脑氧合功能变化及其与脑损伤程度的关系

目的 了解新生儿缺氧后脑氧合功能状态.方法 应用近红外光谱测定技术(NIRS)对39例有围产期缺氧史和42例无缺氧史的新生儿在安静状态下和声音刺激后脑的氧合功能进行了检测,并与脑电图和影像学检查进行了比较.结果 正常新生儿在安静状态下脑氧合状态稳定,声音刺激后脑氧合增强,然而在有缺氧史的新生儿,显示出脑活动抑制,对声音刺激所产生的脑氧合反应性变化减弱.13例病例在监测过程中出现发作性脑氧合降低.结论 在围产期缺氧性脑损伤后,脑氧合功能在一段时间内仍可能是异常的,这种变化与脑损伤程度有关.     

选择性头部亚低温治疗新生儿缺氧缺血性脑损伤对脑血流和氧合代谢的影响

目的探讨新生儿缺氧缺血性脑损伤(hypoxic-ischemicbraindamage,HIBD)选择性头部亚低温治疗期间脑血流和脑氧合代谢的变化。方法38例中、重度HIBD新生儿随机分为常温组和低温组;7例相对正常的新生儿作为对照组。生后6h以内开始治疗,常温组维持体温在36℃,低温组维持鼻咽温度在34℃,低温持续72h,然后自然复温,其它治疗方法两组相同。三组均持续观察84h。三组患儿分别在生后6、12、24、48、72和84h,采用经颅多普勒血流诊断仪测定大脑中动脉的血流速率的变化,采用近红外光谱分析技术测定细胞色素aa3(cytochromeaa3,Cytaa3)的变化。结果低温组新生儿生后6h内收缩期血流速率(Vs)[(250．5±7．69)cm／s],平均血流速率(Vs)[(15．67±5．97)cm／s]、舒张末期血流速率(Vd)[(7．27±5．06)cm／s]和△Cytaa3均较对照组降低,阻力指数(RI)(0．81±0．15)较对照组(0．67±0．09)增加(P均<0．05);低温组Vs和Vm在生后12-48h较常温组增加(P均<0．05),RI降低(P<0．05),且与对照组无差别。与常温组比较,低温组△Cytaa3在生后36-60h显著增加(P<0．05或0．01)。结论中重度新生儿HIBD脑血速率明显降低,存在明显的脑氧合障碍;选择性头部亚低温治疗新生儿HIBD可以改善脑血流动力学和脑氧合代谢状态。     

亚低温治疗过程中缺氧缺血性脑病新生儿脑血流动力学改变及近红外光谱监测的意义

为了改善亚低温治疗效果、尽量减少亚低温对脑血流动力学的负面影响和改善缺氧缺血性脑病患儿的预后,需要进一步探讨在亚低温治疗情况下缺氧缺血性脑病患儿的脑血流动力学紊乱机制,全身血流动力学改变对脑血流的影响,以及如何利用近红外光谱技术监测脑血流并调整血管活性药物使用剂量,以改善亚低温和复温过程中的脑血流波动,帮助患儿平稳渡过...     

Maternal Cerebral Blood Flow and Glucose Metabolism in Pregnancies Complicated by Severe Preeclampsia

Objective. To investigate maternal cerebral blood flow and glucose metabolism in pregnancies complicated by severe preeclampsia compared to normal pregnancies. Methods. A prospective study was conducted including six women with severe preeclampsia and nine normotensive women. Transcranial Doppler (TCD) was performed pre- and postoperatively. The anterior, middle, and posterior cerebral arteries (ACA, MCA, PCA) were selected for study; the cerebral perfusion pressure (CPP) and cerebral flow index (CFI) were calculated for each vessel. To evaluate the cerebral glucose metabolism, F-18 fluorodeoxyglucose positron emission tomography was performed postoperatively. Results. The preoperative CFI in each artery was similar in the comparisons between the two groups. However, the CPP in the MCA and the PCA was higher in the patients with severe preeclampsia. Compared to the preoperative values, the postoperative CPP and CFI in the ACA and the MCA were significantly increased in the severe preeclampsia group, while they were significantly decreased in the control group. Overall, the regional cerebral glucose uptake was not significantly different in comparisons between the two groups. In addition, there was no correlation between the cerebral Doppler indices and their corresponding regional cerebral glucose uptake. Conclusions. Severe preeclampsia was associated with an increase in the cerebral blood flow and perfusion pressure, particularly during the postpartum period, but it was not associated with a significant change in the cerebral glucose metabolism.     

Increased cerebral blood flow in preeclampsia with magnetic resonance imaging

OBJECTIVE: The purpose of this study was to compare third trimester and nonpregnant cerebral blood flow of women with preeclampsia to normotensive control subjects with the use of magnetic resonance imaging techniques. STUDY DESIGN: Nine normotensive pregnant women and 12 untreated women with preeclampsia underwent velocity-encoded phase contrast magnetic resonance imaging of the bilateral middle and posterior cerebral arteries in the third trimester and at 6 to 8 weeks after delivery. The Student t test was used for comparison, with a probability value of <.05 considered significant. RESULTS: Third-trimester large cerebral artery blood flow was significantly higher in preeclampsia. Mean vessel diameter was unchanged, except for the left posterior cerebral artery. There was no difference in mean vessel diameter or cerebral blood flow between the 2 groups while the women were not pregnant. CONCLUSION: Cerebral blood flow is increased significantly in preeclampsia. We hypothesize that increased cerebral blood flow ultimately could lead to eclampsia through hyperperfusion and the development of vasogenic edema.     

缺氧缺血新生鼠脑线粒体形态及功能改变的相关研究

目的　探讨缺氧缺血性脑损伤（ＨＩＢＤ） 新生鼠急性期脑线粒体形态计量学改变及与功能的相关关系。　方法　７ 日龄Ｗｉｓｔａｒ 大鼠（ｎ ＝３３）随机分为ＨＩ１ 小时、ＨＩ２ 小时及假手术对照组,测定其脑线粒体形态特征参数及功能参数。　结果　ＨＩ１ 小时组线粒体平均截面面积、周长分别增加４８ ％ 、２４ ％ ,线粒体比表面、嵴膜面积分别减少１７％ 、３７％ ;ＨＩ２ 小时线粒体平均截面面积、周长、比表面无继续改变,嵴膜平均截线长与嵴膜密度分别较对照组减少６２ ％ 、６８％ ;线粒体密度三组无改变。线粒体嵴膜密度与线粒体呼吸控制比、最大呼吸速率及ＡＴＰ生成量呈正相关。　结论　ＨＩ１小时线粒体形态学的主要改变为肿胀,ＨＩ２ 小时为嵴膜的破坏。线粒体的肿胀与细胞核周质的肿胀变化始终相一致。缺氧缺血新生鼠嵴膜密度的减少与线粒体呼吸功能、能量合成功能障碍密切相关。     

Arterial and Cerebral Venous Blood Gases Differ in Acute Tension Pneumothorax

Tension pneumothorax (TP) complicates the course of respiratory distress syndrome in about 13% of low birth weight infants. If TP is accompanied by hypotension the majority of infants will develop large intraventricular hemorrhages or cerebral ischemic lesions. Severe TP likely produces cerebral ischemia as a consequence of systemic hypotension, but in a previous clinical study we did not demonstrate accompanying abnormalities in the arterial blood gases. Because of the possibility that arterial blood gases do not reflect tissue acid-base abnormalities during TP, this study was designed to compare sagittal sinus blood gases with arterial gases during and following recovery from severe TP in 5-7 day piglets.

During a 4 minute TP mean blood pressure and common carotid blood flow dropped by 75% and 73%, respectively, and the electroencephalogram became isoelectric. Also sagittal sinus pCO₂ rose (from 45.7 to 63.4 mmHg, P < 0.02) and pH fell (from 7.31 to 7.23, P < 0.02). During TP, end-tidal CO₂ decreased (from 47.5 to 27.0 mmHg, P < 0.005) indicating that the rise in venous (and tissue) pCO₂ was a consequence of reduced CO₂ excretion by the lungs. However, as sagittal sinus pCO₂ rose, arterial pCO₂ fell (from 41.6 to 32.4 mmHg, P < 0.02). Thus, as in other clinical conditions where the circulation is markedly compromised, during severe TP, venous and arterial pCO₂ and pH diverge and arterial blood gases cannot be used to evaluate tissue acidosis.     

Umbilical cord blood for newborn DNA identification

OBJECTIVE: To compare umbilical cord blood with newborn heel stick blood for newborn DNA identification. DESIGN: Prospective, correlational, comparative analysis utilizing a convenience sample of birth mothers and newborns. SETTING: Labor and delivery unit in a large, private, not-for-profit community hospital. PARTICIPANTS: One hundred thirty four mother/infant dyads participated. Birth mothers were at least 18 years of age and able to read and understand English. SAMPLES: Blood samples were collected from each newborn utilizing the umbilical cord and a heel stick. A blood sample was collected from each mother utilizing a finger stick. MAIN OUTCOME MEASURE: Computerized short tandem repeat analyses and visual matching to identify positive matches between the umbilical cord blood sample and heel stick sample. RESULTS: Umbilical cord blood contains a DNA profile identical to the newborn heel stick sample that can be used to identify a newborn. CONCLUSION: Umbilical cord blood samples are a valid source of newborn DNA identification.     

雌激素替代治疗对绝经后妇女血清一氧化氮和脑血流的影响

目的 :探讨雌激素替代治疗对绝经后妇女大脑中动脉血流的影响及其作用机制。方法 :接受结合型雌激素 0 .6 2 5mg d治疗 3个月的绝经后妇女 2 5例 ,于治疗前后对比观察血清雌二醇 (E2 )、一氧化氮 (NO)及大脑中动脉搏动指数 (PI)变化。结果 :ERT治疗3个月后血清E2 、NO浓度较治疗前明显升高 (P <0 .0 1) ,而大脑中动脉PI明显降低 (P<0 .0 1)。同时 ,服药前后NO升高与PI降低有显著相关性 (r =0 .56 ,P <0 .0 5)。结论 :ERT可增加脑血流量 ,其机制可能与NO水平升高有关