Clinical Study On Left Atrial Pressure Control The Adjustment Of Capacity In Open Heart Operation

As the inspection equipment and technology development, the rate ofcongenital heart disease detection is improved. Dates shows that thecongenital heart disease incidence rate has reached6per thousand to9perthousand in the newborn of China, which occupies the first place of the birthdefects[1], and60%～70%children need operation treatment and the quality oflife compared to normal subjects almost has no difference after operation.Now our heart surgery operation has been basically mature, as the techniquesof cardiac surgery, cardiopulmonary bypass (CPB) and anaesthetic improves,more and more people have accepted operation treatment of congenital heartdisease. As the number of heart patients increases, operation indicationsrelaxation and operation difficulty increases, the number of operation oncritically ill patients are more and more. The adjustment of respiratory andcirculation is not only relation to the successful of surgen but also theprognosis of the patients after CPB (cardiopulmonary bypass) especially in thecritically ill patients. Circular function maintain relies on active heart pumpsupport, blood volume supplement and correct the blood dilution[2], accordingto Frank-Starling Starling’s law[3]that the pressure can be used to evaluate thecapacity, so the central venous pressure (CVP) can be used to assess left atrialpressure (LAP) when there are no difference between the left and right cardiacfunction, so CVP reflects not only the right heart function but also the leftheart function, thus CVP can accurately reflect the changes in blood volume atthis condition which is widely used in a variety of critically ill patients rescuein clinical. However in Atrial Septal Defect (ASD), Tetralogy of Fallot (TOF)and Mitral Stenosis (MS) patients, that persist the long time of left ventricularblood decreasing relatively due to the left ventricular volume reductionrelatively, have the poor left ventricular function. When the intracardiac lesion has been corrected, the left cardiac blood increased that the left ventricularwould not be compensate, which would due to elevate LAP. At this time,using CVP to assess LAP was error and would assess the wrong patient’scondition[4]. This paper mainly observed the direct left atrial pressuremonitoring through atrial interval level to left atrial by using children singlelumen catheter and estimating left ventricular volume, so guiding the use ofvasoactive drug and the fluid therapy in surgical operation patients.Objective: This experiment mainly observed the trends of LAP and CVPin these patients after CPB. Observation the contulation of heart functionrecovery in the small left ventricle patients, thus we can use CVP to estimationLAP at this time. The rapid infusion fluid therapy after CPB gave the furtherproof that LAP is more accuract.Methods: We collected clinical information and data of40patients whoneeded open-heart operation including ASD、TOF、MS and VSD from July2011to March2012in the department of Cardial Surgery of our hospital.There were10participants in VSD group,10participants in ASD group,11participants in MS group and9participants in TOF group.we controled LAP<13mmHg, with the minimum of LAP to maintain normal BP, HR at the endof CPB. According to the relationship between LAP and CVP, we judged thefunction of left and right heart, adjusted the blood volume first, and thenadjusted the dose of positive inotropic drug in all patients.(1) We haverecorded the data of LAP and CVP in8h after CPB.(2) when LAP decreasedby5～6mmHg, or mean arterial pressure decreased20%or30mmHgcompared to basal blood pressure after CPB, and then we conducted theexperiments of fast rapid infusion, pressurized the remaining blood to300mmHg,10ml/kg input within3～10minius. We have recorded the data ofLAP, CVP, heart rate and blood pressure before and after fast rapid infusion.(3) We have recorded the information of application positive inotropic drugsbefore leaving operation room.(4) We have observated on the safety of leftatrial catheter.Results: we used SPSS13.0statistical software process to deal with the data:(1) on the observing the trends of LAP and CVP after CPB, in VSDgroup, the trends of LAP and CVP had no statistical difference (P>0.05);inASD group, the trends of LAP and CVP had statistically significant (P<0.05),compared with the control group, the differences in6h were statisticallysignificant (P<0.05); in MS group, the trends of LAP and CVP had statisticsdifference (P<0.05), compared with the control group, the differences in2hwere statistically significant (P<0.05); in TOF group, the trends of LAP andCVP had no statistical difference (P>0.05).(2)For the rapid fluid therapy afterCPB, in VSD group, the changes of LAP and CVP had no significantdifference (P>0.05); in ASD group, the changes of LAP and CVP hadstatistically significant before and after rehydration (P<0.05); in MS group,the changes of LAP and CVP had statistically significant difference (P<0.05);in TOF group, the changes of LAP and CVP had no significant difference(P>0.05).(3) The number of ceasing inotropic drugs,7cases in ASD group,1cases in MS group, and4cases in VSD group case group.(4) All of atrialcatheteres were successfully pull out; no bleeding and hematoma, there werenot any atrial septal level shunting after repeated ultrasound heartbeatexamination revealed.Conclusion:1. The trends of LAP and CVP were found had a highdegree of consistency in VSD group and in the normal range.2. As the leftventricular function recovery in ASD and MS group, the difference of LAPand CVP narrows gradually, respectively at2.8±2.5h and2.3±1.5h returnedto normal, thus we can use CVP instead of LAP to estimate the in vivocapacity.3. Because of successful of intracardiac correction, LAP and CVPare in the normal range in TOF group, so we can use changes of LAP andCVP to assess orthopedic conditions in TOF.4. In the rapid infusion therapy,LAP rise far greater than CVP in ASD and MS groups; while in the controlgroup, VSD group, LAP and CVP raise the same, which proved LAP guidinginfusion in small left ventricle is more accuracy.5. Monitoring of LAP toguide fluid therapy, and guide positive inotropic drug adjustment.6. It was asafe, simple and economical method to moniter left atrial pressure by putting the left artrial catheter througth atrial septum.