室间隔缺损修补术患儿不同呼气末二氧化碳状态脑氧饱和度与血流动力学的关系

Relationship between cerebral oxygen saturation and hemodynamics under different end -tidal carbon dioxide partial pressure in children with ventricular septal defect

目的研究不同呼气末二氧化碳（PetCO2）状态下，行室间隔缺损（VSD）修补术患儿麻醉诱导阶段区域脑组织氧饱和度（rScO2）与各血流动力学参数的关系。方法选取2017年4月至5月在北京安贞医院行择期VSD修补术的患儿25例，月龄2～37个月（中位数6个月）。全身麻醉气管插管后，建立桡动脉血压监测并使用MostCare血流动力学监测仪，使用Fore-Sight连续监测右侧额部rScO2。调整机械通气参数，使PetCO2依次维持在30（T1）、35（T2）、40（T3）、45（T4）mmHg（1 mmHg＝0.133 kPa）。记录T1、T2、T3、T4点脉搏血氧饱和度（SpO2）、心率（HR）、收缩压（SysP）、重脉压（DicP）与舒张压（DiaP）的差值（Pdic-a）、每搏指数（SVI）、心脏指数（CI）、体循环阻力指数（SVRI）、脉压变异度（PPV）。结果1．组内参数比较：rScO2在T4、T3、T2、T1分别为（80.5±4.0）%、（78.2±4.6）%、（74.4±5.7）%、（70.8±6.5）%，T2、T3和T4的rScO2水平均显著高于T1，差异均有统计学意义（均P〈0.05）。T3、T4的SysP[分别为（85±9） mmHg、（84±10） mmHg]显著低于T1[（92±15） mmHg]，差异均有统计学意义（均P〈0.05）。T2、T3、T4的DicP分别为（64±12） mmHg、（60±10） mmHg、（59±9） mmHg，显著低于T1[（68±15） mmHg]，差异均有统计学意义（均P〈0.05）。T2、T3、T4的DiaP分别为（44±6） mmHg、（41±6） mmHg、（41±6） mmHg，显著低于T1[（47±7） mmHg]，差异均有统计学意义（均P〈0.01）。T4的SVRI[（1 382±262） dyne·s cm－5·m2]显著低于T1时点[（1 486±241） dyne·s cm－5·m2]、T2[（1 440±279） dyne·s cm－5·m2]、T3[（1 418±266） dyne·s cm－5·m2]，差异均有统计学意义（均P〈0.05）。T3、T4的PPV[（11±4）%、（13±5）%]明显下降，与T1[（18±12）%]比较差异均有统计学意义（均P〈0.05）。2.相关性分析：PetCO2与rScO2呈正相关（r＝0.582，P〈0.01）。T1点rScO2与DiaP、DicP呈正相关（r＝0.600、0.658，均P〈0.01），与SysP、CI、SVI、Pdic-a均呈正相关（r＝0.460、0.424、0.522、0.534，均P〈0.05），与HR、PPV均呈负相关（r＝－0.450、－0.490，均P〈0.05）。T2点rScO2与DiaP、DicP均呈正相关（r＝0.689、0.692，均P〈0.01），与SysP、SVI均呈正相关（r＝0.534、0.445，均P〈0.05）。T3点rScO2与SysP呈正相关（r＝0.495，P〈0.05），与PPV呈负相关（r＝－0.562，P〈0.01）。T4点rScO2与血流动力学监测值均无相关性（均P〉0.05）。结论VSD患儿在麻醉诱导阶段，随着PetCO2水平升高，脑氧合明显增加。PetCO2在30、35 mmHg时，脑氧合主要受血流动力学影响；PetCO2在40、45 mmHg时，脑氧合主要受PetCO2影响，而血流动力学对其影响减弱。

ObjectiveTo study the relationship between regional cerebral tissue oxygen saturation （rScO2） and hemodynamic parameters under different end-tidal carbon dioxide partial pressure （PetCO2） levels during anesthesia induction period in children undergoing ventricular septal defect（VSD） repair.MethodsA total of 25 patients aged from 2 to 37 months （median 6 months） were enrolled, who received selective VSD repair at Beijing Anzhen Hospital from April to May 2017.After admission, anesthesia induction and intubation, invasive radial artery pressure were established routinely and hemodynamic device-MostCare was used, Fore-Sight was used to monitor rScO2 of the right frontal brain.By means of adjusting mechanical ventilation parameter, PetCO2 was maintained at 30 （T1）, 35 （T2）, 40 （T2）, 45 （T3） mmHg（1 mmHg=0.133 kPa） in sequence.Pulse oxygen saturation （SpO2）, heart rate （HR）, systolic pressure （SysP）, difference between dicrotic pressure（DicP） and diastolic pressure（DiaP） （Pdic-a）, stroke volume index （SVI）, cardiac index （CI）, systemic vascular resistance index （SVRI）, and pulse pressure variation （PPV） were recorded at T1, T2, T3 and T4.Results（1） Comparison among groups： rScO2 at T4, T3, T2 and T1 were（80.5±4.0）%, （78.2±4.6）%, （74.4±5.7）%, （70.8±6.5）%, respectively, rScO2 at T2, T3 and T4 were higher than that at T1, and the differences were statistically significant （all P〈0.05）. SysP at T3 [（85±9） mmHg] and T4 [（84±10） mmHg] were lower than that at T1 [（92±15） mmHg], and the differences were statistically significant （all P〈0.05）. DicP at T2[（64±12） mmHg], T3[（60±10） mmHg], and T4 [（59±9） mmHg]were significantly lower than that at T1 [（68±15） mmHg], and the differences were statistically significant （all P〈0.05）. DiaP at T2[（44±6） mmHg], T3[（41±6） mmHg], and T4 [（41±6） mmHg ]were lower than that at T1[（47±7） mmHg], and the differences were statistically significant（all P〈0.01）. SVRI at T4[（1 382±262） dyne·s cm-5·m2]was significantly lower than those at T1 [（1 486±241） dyne·s cm-5·m2], T2[（1 440±279） dyne·s cm-5·m2] and T3[（1 418±266） dyne·s cm-5·m2], and the differences were statistically significant （all P〈0.05）. PPV at T3 [（11±4）%] and T4[（13±5）%] was significantly lower than that at T1[（18±12）%], and the differences were statistically significant （all P〈0.05）. （2） Correlation analysis： in total population, PetCO2 was positively correlated with rScO2 （r=0.582, P〈0.01）. At T1, rScO2 was positively correlated with DiaP and DicP （r=0.600, 0.658, all P〈0.01）, as well as SysP, CI, SVI, Pdic-a （r=0.460, 0.424, 0.522, 0.534, all P〈0.05）, rScO2 was negatively correlated with HR and PPV （r=-0.450, -0.490, all P〈0.05）. At T2, rScO2 was positively correlated with DiaP and DicP （r=0.689, 0.692, all P〈0.01）, as well as SysP, SVI （r=0.534, 0.445, all P〈0.05）. At T3, rScO2 was positively correlated with SysP （r=0.495, P〈0.05）, and negatively correlated with PPV （r=-0.562, P〈0.01）. At T4, the rScO2 was not correlated with any hemodynamic parameters （P〉0.05）.ConclusionsDuring anesthesia induction in ventricular septal defect children, rScO2 increases significantly with the increase in PetCO2.When PetCO2 is at 30 and 35 mmHg, rScO2 is mainly affected by hemodynamics.When PetCO2 is at 40 and 45 mmHg, rScO2 is mainly affected by PetCO2, but less affected by hemodynamics.