室间隔缺损和法乐四联症患儿心脏手术中区域脑氧饱和度对比研究

Comparison of Regional Cerebral Oxygen Saturation During Cardiac Surgery in Children With Ventricular Septal Defect and Tetralogy of Fallot

目的:使用Fore-Sight近红外光谱仪比较室间隔缺损(VSD)和法乐四联症(TOF)患儿心脏手术中区域脑组织氧饱和度(rScO_2)变化。方法:选择3～36个月龄患儿共60例,其中VSD组28例,TOF组32例。在麻醉诱导后(t_0)、切开心包(t_1)、体外循环全流量后5 min(t_2)、脱机前5 min(t_3)、脱机时(t_4)、改良超滤结束(t_5)、术毕(t-_6)记录各时点rScO_2、脉搏氧饱和度(SpO_2)、收缩压、舒张压、心率、每搏量指数、心指数、体循环阻力指数、动脉压力升支最大斜率(dp/dt max)。结果:(1)两组患儿:rScO_2均在脱机时(t4)处于最低点,与t_0点比较均显著降低(均P<0.05);t_5时rScO_2、每搏量指数、心指数、dp/dt max较t4时均显著增加(均P<0.001)。(2) TOF组患儿:组内t_5和t_6与t_0相比,rScO_2及SpO_2均显著增加(P均<0.05);与VSD组比较,TOF组t_0～t_2时r ScO_2显著降低(P均P<0.05),改良超滤后r ScO_2增加比率更大(P<0.05); t_0和t_1时点rScO_2和SpO_2呈显著正相关(r=0.35,P<0.05及r=0.64, P<0.01)。(3)患儿总体样本年龄、体重与rScO_2在t_0、t_1、t_3、t_4、t_5和t_6均呈显著正相关(均P<0.01)。改良超滤后心指数增加和rScO_2增加成正相关(r=0.41,P<0.05),且两者增加量均与年龄呈显著负相关(r=-0.30;r=-0.34,均P<0.05)。结论:rScO_2与年龄和体重有密切关系。与VSD患儿比较,TOF患儿在双心室矫治术前脑氧供低下,经矫治术其脑氧合明显改善;改良超滤使机体血流动力学状况和rScO_2得到改善,其中TOF患儿和年龄较小的患儿受益更大。脱离体外循环前后易发生脑氧降低,临床应加强脑氧供-需平衡的维护。

Objectives： To compare regional cerebral tissue oxygen saturation （rScO2） changes during cardiac surgery in children with ventricular septal defect （VSD） and tetralogy of Fallot （TOF）. Methods： A total of 60 children aged 3-36 months were enrolled （28 in VSD group 32 in TOF group）, rScO2 was monitored by Fore-Sight near-infrared spectroscopy device, rScO2, pulse oxygen saturation （SpO2）, systolic pressure, diastolic pressure, heart rate, stroke volume index, cardiac index, systemic vascular reststance index the maximal slope of systolic upstroke （dp/dt max） were obtained at following time points： after anesthesia induction （to）, pericardium opening （q）, 5 min after cardiopulmonary bypass （CPB） initiation （t2）, 5 min before separation from CPB （t3）, separation from CPB （t4）, post-modified ultrafiltration （ts）, end of surgery （t6）. Results： （1） The lowest rScO2 value was observed at separation from CPB （t4）, and which was significantly lower than that at to （P〈0.05） for both groups; rScO~, stoke volume index, cardiac index, and dp/dt max at t5 were significantly higher than at t4 （all P〈0.001） for both groups. （2） rScO2 and SpO2 were significantly higher at t5 and t6 than at to （both P〈0.05） in TOF group, rScO2 at t0-t2 was significantly lower in TOF group than in VSD group （both P〈0.05）. rScO2 increased more significantly after modified ultrafiltration and rScO2 was positively correlated with SpOz at to and t~ （r=0.35, P〈0.05 and r=0.64, P〈0.01） in TOF group. （3） In the total cohort, rScO2 was positively correlated with age, weight at t0, tl, t3, t4, ts, t6 （allP〈0.01）. After modified ultrafiltration, the increase in cardiac index was positively correlated with increase in rScO2 （1=0.41, P〈0.05）, and the amount of cardiac index and rScO2 increases were negatively correlated with age （r=-0.30; r=-0.34, both P〈0.05）. Conclusions： rScO2 is closely related with age and weight. Cerebral oxygen delivery before biventricular surgical correction is lower in TOF group than in VSD group, and the cerebral oxygenation improves significantly after surgical repair. Modified ultrafiltration could significantly improve systemic hemodynamics and rScO2, and TOF children and younger children benefit more from modified ultrafiltration. Pre- and post-separation from CPB period is vulnerable to cerebral desaturation, it is therefore of importance to maintain the cerebral oxygen delivery-consumption balance at these periods for children with TOF and VSD undergoing surgical repair.