Relations among cerebral oxygen saturation, cerebral blood flow velocity and hemodynamics during surgical repair of ventricular septal defect

Liu Yaguang; Han Ding; Ouyang Chuan

doi:10.3760/cma.j.issn.1673-4777.2018.04.011

Abstract：Objective To observe changes of cerebral oxygen saturation (rScO2),cerebral blood flow velocity and hemodynamics during surgical repair of ventricular septal defect.Methods Eighteen children scheduled for ventricular septal defect repair from May to September 2017 in Beijing Anzhen Hospital,Capital Medical University were enrolled;the mean age was (0.59 ± 0.19)years;the mean weight was (6.4 ± 1.6)kg.After anesthesia induction and intubation,anesthesia was maintained with intravenous sufentanil 2-4 μg/(kg · h),midazolam 0.2-0.4 mg/(kg · h) and pipecuronium 80-160 μg/(kg · h).rScO2 was monitored by Fore-Sight near-infrared spectroscopy;middle cerebral artery blood flow velocity was monitored by transcranial Doppler;hemodynamic measurements were monitored by MostCare (pressure recording analytical method).rScO2,systolic peak cerebral blood flow velocity(Vs),diastolic peak cerebral blood flow velocity(Vd),mean cerebral blood flow velocity (Vm),pulsitility index (PI),resistance index (RI),systolic pressure (SysP),diastolic pressure (DiaP),dicrotic pressure(DicP),systemic vascular resistance index (SVRI),heart rate (HR),stroke volume index (SVI),cardiac index(CI),the maximal slope of systolic upstroke (dp/dtmax),pulse pressure variation (PPV)and end-tidal carbon dioxide partial pressure (PETCO2) were recorded before skin incision(T1),during pericardium incision(T2),after withdrawing from cardiopulmonary bypass (T3),after modified ultrafiltration (T4) and at the end of surgery(T5).Results Vm,SysP,SVRI and dp/dtmax at T2 were significantly higher than those at T1;rScO2,Vd,DiaP,DicP,SVI,CI,PETCO2 at T3 were significantly lower and PI,RI were significantly higher than those at T1,T2,T4,T5;Vs,Vm,SVRI,HR and PPV at T5 were significantly lower than those at T4 (all P ＜0.05).At T1:Vs was positively correlated with age,Vm was positively correlated with DicP (r =0.485,0.493,both P ＜ 0.05).At T2:Vs and Vm were positively correlated with age.At T3:Vs and Vm were positively correlated with rScO2 (r =0.695,0.526,both P ＜ 0.05).At T4:Vm and Vd were positively correlated with age (r =0.566,0.577,both P ＜ 0.01);Vs,Vd and Vm were negatively correlated with PPV (r =-0.661,-0.488,-0.659,all P ＜ 0.05).At T5:Vm and Vd were positively correlated with age,rScO2 was positively correlated with dp/dtmax (r =0.453,0.625,0.489,all P ＜ 0.05).Conclusions In surgical repair of ventricular septal defect in children,cerebral blood flow velocity is closely related to age and hemodynamics.Cerebral blood flow velocity has influence on rScO2 during cardiopulmonary bypass.Ultrafiltration can significantly increase cerebral blood flow velocity,reduce cerebral vascular resistance and increase rScO2.