不同疾病状态下新生儿脑组织氧合变化的对照研究

目的采用近红外光谱测定技术（NIRS）检测新生儿脑组织氧饱和度（rSO2）,探讨不同疾病状态下新生儿脑rSO2的变化规律,为临床应用提供依据。方法2007年4月至2008年10月以无特殊疾病的223名足月儿作为正常组足月儿亚组,于生后3d内测定脑rSO2;以196例患有可能影响脑氧合疾病的新生儿作为疾病组,在疾病急性期测定脑rSO2。疾病组分为呼吸系统疾病亚组（97例）,分析脑rSO2与PaO2的关系;循环系统疾病亚组（44例）,分析脑rSO2与心率的关系;脑损伤亚组（55例）,分析脑rSO2与脑血流的关系。结果①疾病组脑rSO2为（56±6）%,显著低于正常组足月儿亚组（P〈0.05）。②轻度与重度呼吸系统疾病亚组脑rSO2分别为（60±3）%和（54±6）%,轻度和重度循环系统疾病亚组脑rSO2分别为（59±3）%和（53±6）%,轻度和重度脑损伤亚组脑rSO2分别为（59±3）%和（54±4）%。3个疾病亚组中轻度与重度间脑rSO2差异均有统计学意义（P〈0.01）。③呼吸系统疾病亚组脑rSO2与PaO2呈三次方程曲线（y=-62.93＋4.75x-0.059x2＋0.00024x3）。PaO2≥60mmHg时,脑rSO2约为62%,脑氧合正常;PaO2〈50mmHg时,脑rSO2〈57%,脑组织缺氧。循环系统疾病亚组脑rSO2与心率呈二次方程曲线（y=1.11＋0.8241x-0.0027x2）。心率在105～200.min-1时,脑rSO2〉58%,脑氧合正常;心率低于105.min-1或高于200.min-1时,脑rSO2〈58%,脑组织缺氧。脑损伤亚组脑rSO2〈58%时,大脑前动脉血流平均速度代偿性增高,阻力指数偏低,脑损伤较重。结论严重疾病状态下可同时伴有脑组织缺氧。脑rSO2的变化与PaO2、心率及脑血流的变化密切相关。NIRS技术为临床提供了一种可靠的、有价值的脑氧合检测方法,有助于临床直观量化地发现脑组织的缺氧。

A controlled study on the changes of cerebral oxygenation in neonates with different diseases

Objective To investigate the rules of cerebral oxygen saturation （rSO2） changes in neonates with different diseases using near infrared spectroscopy （NIRS） and give useful information for clinical application.Methods A multicenter randomized clinical trial was conducted in nine regional large hospitals participated from Jan 2007 to Oct 2008.223 term neonates without special diseases were enrolled as the normal group and the cerebral rSO2 was detected at 1,2 and 3 days after birth respectively using the NIRS human tissue oximeter （TSAH-100）.At the same time,196 neonates with diseases possibly effectting the changes of cerebral oxygenation were enrolled as the disease group and the cerebral rSO2 was detected during acute periods.The statistical differences of the cerebral rSO2 between two groups were analyzed. The disease group was further divided into 3 subgroups：respiration disease subgroup （n=97）,circulation disease subgroup （n=44） and brain injury subgroup（n=55）.The differences of the cerebral rSO2 among different severities of illness were tested.The relationship between cerebral rSO2 and arterial oxygen pressure （PO2） was discussed in respiration disease subgroup. In addition,the relationship between cerebral rSO2 and heart rates was also investigated in circulation disease subgroup.The relationship between cerebral rSO2 and the mean velocity （Vm） and resistent index （RI） in anterior cerebral artery was also investigated in brain injury subgroup.Results ①In disease group the cerebral rSO2 was （56±6）%,which was significantly lower than the normal group （t=21.729,P〈0.05）. ②The cerebral rSO2 of the neonates with serious respiratory disease was （54±6）%,which was significantly lower than those with mild abnormality （60±3） %（ P〈0.05）. The cerebral rSO2 of the neonates with serious circulation disease was （53±6）%,which was significantly lower than those with mild abnormality （59±3） %（ P〈0.05）. The cerebral rSO2 of the neonates with severe brain injury was （54±4）%,which was significantly lower than those with mild injury （59±3）% （ P〈0.05）.③In the respiratory disease subgroup the cerebral rSO2 was positively correlated with PO2（y=-62.93＋4.75x-0.059x2＋0.00024x3）.When PO2 was above 60 mmHg,rSO2 was about 62%,cerebral oxygenation was normal. When PO2 was under 50 mmHg,rSO2 was lower than 57%,cerebral hypoxia happened.In the circulation disease subgroup cerebral rSO2 was positively correlated with the heart rates of neonates（y=1.11＋0.8241x-0.0027x2）. When heart rates were from 105 to 200 per minute,rSO2 was above 58%,cerebral oxygenation was normal. when heart rate were under 105 or above 200 per minute,the rSO2 decreased to 58% ,there would be cerebral hypoxia. In the brain injury subgroup,when rSO2 was below 58%,the mean velocity （Vm） in cerebral anterior artery was compensatively increased and resistent index （RI） was decreased,and the brain injury was serious.Conclusions The cerebral hypoxia may happen in patients with serious diseases.NIRS objectively reflected the cerebral oxygenation alteration,and therefore was a valuable and reliable method for monitoring cerebral hypoxia of neonates in clinic and possibly helpful to find cerebral hypoxia in neonates.