The Relationship Between Invasive Blood Hemodynamic Parameters And Arterial Blood Pressure In Patients With Hypertensive Emergencies

OBJECTIVE:To observe the changes of invasive blood hemodynamics and assesses their roles in the initiation and the development of hypertensive emergencies before and after the patients were treated by lowing blood pressure agents.METHODS:30 inpatients with hypertensive emergencies were enrolled from department of cardiology in the first affiliated hospital of Guangxi Medical University.Each patient was injected with the compound of 50mg Sodium nitroprusside and 50ml 5%glucose solution by intravenous minipump(initially at 0.25μg/kg·min,titrated according to blood pressure level,and blood pressure were controlled below 90/60mmHg.The parameters of hemodynamics, reflecting the left and right ventricular preload,such as central venous pressure (CVP),right atrial pressure(RAP),pulmonary capillary wedged pressure (PCWP);The parameters of hemodynamics relating to right ventricular and Pulmonic pressure,such as right ventricular pressure(RVP),pulmonary arterial pressure(PAP);pulmonary vascular resistance(PVR),systemic vascular resistance(SVR),total peripheral vascular resistance;The parameters of hemodynamics relating to left ventricular contractile function,such as cardiac output(CO),cardiac index(CI),stroke volume(SV);and those parameters were measured by Swan-Ganz catheter on four different time points during the treatment processes:first time:at admitting;second time point:MBP declined by 25%or DBP declined by 10%—15%;third time:MBP were controlled at the normal level;and the fourth:24h after the MBP normal level were attained. Analysis of variance,linear correlation analysis and multivariable stepwise regression analysis were used to accessed the relationship between parameters of hemodynamics and blood pressure changes.RESULTS:The study showed:(1)The parameters of hemodynamics reflecting cardiac the loads of cardiac system,such as CVP,RAP,PCWP,PVR,SVR are higher remarkably at time point before the initiation of medical therapy than the rest three time points(P＜0.05);those parameters at secondary time are also higher than third time and fourth time(P＜0.05);while the parameters at third time and fourth time have no statistic differences(P＞0.05).(2)The parameters of hemodynamics reflecting left ventricular contractile function,such as CO,CI,SV decreased remarkably.Those parameters at first time are lower than rest three time points(P＜0.05);and the parameters at secondary time are also higher than third time point and fourth time point(P＜0.05);while the parameters at third time and fourth time have no statistic differences(P＞0.05).(3)The parameters of hemodynamics reflecting cardiac load have a positive correlation with SBP,MBP and DBP,but negatively correlate with those parameters reflecting cardiac contractile(r＜-0.206,P＜0.05).CONCLUSIONS:(1)the parameters of hemodynamics reflecting cardiac preload and cardiac afterload are at high level,the parameters of hemodynamics reflecting left ventricular contractile function depress evidently,and it makes sense that HE maybe a kind of state that low cardiac output accompany high vascular resistance.(2)PCWP serves as the most intimate factor and SVR as the most important factor affecting blood pressure.(3)Lowing blood pressure agents can improve distinctly the abnormal state of the hemodynamics HE,depressing vascular resistance and increasing CO.