Evaluation Of Ventricular Performance Using Volumetric Pulmonary Artery Catheter And Transesophageal Echocardiography In Patients Undergoing Coronary Artery Bypass Grafted With CPB

ObjectiveTo evaluate the ventricular function using volumetric pulmonary artery catheter(Swan-Ganz catheter)in patients undergoing coronary artery bypass grafted(CABG)with extracorpreal circulation(CPB)by the contrast study of volume loading experiment,and to judge the effect of volumetric variation to patients' heart function,and also to estimate the creditability and sensitivity of this two kinds of monitoring methods in estimation of perioperative cardiac function.MethodsEight patients(7 males,1 female)aged 45-66 yrs weighing 63-84 kg undergoing CABG had been studied.Their cardiac functions were graded according the NYHA classification asâ… orâ…¡.Radial artery was cannulated before anesthetic induction for blood pressure monitoring.Anesthesia was induced with midazolum 0.05 mg/kg,fentanyl 10ug/kg,etomidate 0.3mg/kg,esmoron 0.6-0.8mg/kg。The probe(7 MHz)of the transesophageal echocardiography(TEE,Sonos 5500,HP)was placed into esophagus after tracheal intubation for measurement of left ventricular end diastolic volume and area(LVEDV,LVEDA)and end-systolic volume and area(LVSEV,LVSEA)and ejection fraction(LVEF).Swan-Ganz Catheter(type 774HF75,Edwards Life Science Co.)was placed via right internal jugular vein for measurement of RVEDV,RVESV and RVEF.Gelofusion 4 ml/kg bodyweight was infused within 10 min.by a average speed.The cardiovascular parameters mentioned above were measured at the following 6 time points such as before Gelofusion infusion and 1,3,5,7,10 minutes after Gelofusion infusion with the monitoring measurement of TEE and Swan-Ganz Catheter.The time point was recorded as T₀,T₁,T₂,T₃,T₄,T₅.and the parameters were further compared respectively.In the interval between T₀ and T₁,some parameters are increased,such as RVCCI,RVCCO,RVEDV,RVEDVI,RVEF,MPAP,CVP,the results showed that when the volumetric load was kept increasing,it would bring the same result in the output of right ventricle,and showed from the changing rate of these parameters,the amount of change in CVP was very apparently bigger than the one of other parameters.It demonstrated that when the experiment of volumetric load was proceeding,the change of CVP was the most apparent and it happened in the very beginning.In the mean time,PAWP,a parameter standing for left ventricular function was increasing too.ResultsLVEF at T1(measured by TEE),right ventricular parameters such as RVCCO at T₅, RVCCI at T₂,T₃,T₄,T₅,RVEDV at T₄,T₅,RVEDVI at T₅ and CVP were significantly changed after Gelofusion infusion when these values were compared with the baselines(P＜0.05).There were no significant changes in other parameters by both methods after infusion. Conclusionwhen the volumetric load changed,left and right ventricular function did not give the same response in the mean time;we had drawn a conclusion that in the period of cardiac operation,especially to the patients with poor ventricular function,although there were a lot of advantages in monitoring measurement of TEE and Swan-Ganz Catheter respectively,they could not be used solely to judge left or right heart function,and some times,to some very important cases,this two measurements should be used cooperatively in order to offer more significant parameters to the treatment.