Hemodynamic Effects Of Milrinone In Elderly Patients With Cardiac Insufficiency During Anesthesia Induction

Objective Elderly patients with cardiac insufficiency usually accompanied cardiac function decreased,peripheral vascular resistance increased,and anesthesia tolerance severely reduced. Anesthesia drugs currently used have certain cardiac function inhibition and endotracheal intubation stress response can led to serve hemodynamics volatility. Both increased the risk during anesthesia induction. Milrinone is a phosphodiesterase inhibitor, has a positive inotropic effect as well as peripheral vasodilatation,reduced vascular resistance.Goal-directed fluid therapy(GDFT) is a individual liquid treatment based on patients general conditions and circulation capacity status with hemodynamics index as goal-oriented. GDFT can optimize cardiac preload,maintain effective blood volume,protect the body's microcirculation and tissue oxygen supply,avoid tissue edema,heart failure and other complications.In this study,we will obverse hemodynamic effects of milrinone in elderly patients with cardiac insufficiency under Flotrac/Vigileo monitoring during anesthesia induction.Methods 80 cases of elective surgery patients undergoing general anesthesia, aged60 to 89 years old, New York Heart Association(NYHA) cardiac functional class?-? and ASA?-?,were randomly divided into into milrinone group(group M,n=40)and control group(group C, n=40) by using a random number table. Group M intravenous milrinone 50ug/kg 10 min before anesthesia induction, instead0.375ug/kg/min intravenous when anesthesia induction.Group C intravenous equal doses normal saline 10 min before anesthesia induction. Both groups receive goal-directed fluid therapy with the goal of SVV>13%. The cardiac output(CO),cardiac index(CI),systemic vascular resistance(SVR),central venous pressure(CVP),mean artery pressure(MAP) and heart rate(HR)of the two group patients were recorded in T0(10min before anesthesia induction),T1(anesthesia induction),T2(3min after anesthesia induction),T3(endotracheal intubation),T4(1min after intubation),T5(3min after intubation),T6(5min after intubation).The usage count of vasoactive drugs and the treatment times of bradycardia were recored.The dosage of anesthesia induction drugs were also recored.Results Compared with T0,the CO and CI at T1 were significantly increased in group M(P <0.01),and the SVR at T1-T6 was significantly decreased in group M(P<0.05). the CO and CI at T2-T6 were significantly decreased in group C(P <0.01),and the CVP was significantly increased in both groups(P <0.05). Compared with group C,the CO and CI at T1-T6 were significantly increased in group M(P <0.01),and the SVR was significantly decreased(P <0.05).Compared with group C,the usage count of vasoactive drugs and the treatment times of bradycardia were significantly reduced.Conclusion Under Goal-directed fluid therapy, milrinone can optimize cardiac preload and afterload, enhance cardiac contractility, increase cardiac output and cardiac index,reduce peripheral vascular resistance in elderly patients with cardiac insufficiency during anesthesia induction.And hemodynamics are more stable during anesthesia induction.