The Application Research Of Impedance Cardiography In The Very Elderly Patients With Hypertension

Hypertension is one of the most common cardiovascular disease,according to the results of2002China’s large-scale hypertension incidencepopulation sampling survey, our country adult (18years old) hypertensionprevalence was18.8﹪. In2006China’s population quantity and structure,there were at present in our country, and in elderly hypertensive patients as themain body. Although countries have issued guidelines, new antihypertensivedrugs continuously researched and developmented, but so many high bloodpressure patients, by only a small percentage of patients get reasonablediagnosis and treatment, to recommend blood pressure value (<140/90mmHg). The Hypertension disease become one of the main diseases threat tothe health of the Chinese people, especially the older people’s quality of life,its early diagnosis and treatment become a pressing problem of modernmedine. Despite defined as a clinical syndrome mainly to high blood pressure,hypertension is characteried in the cardiac output, systemic vascular resistanceand artery compliance for the abnormal. These hemodynamic factors onhypertension disease diagnosis and risk stratification, treatment is of greatsignificance. Impedance Cardiography is a unique, highly accuratenoninvasive method of monitoring hemodynamic parameters. Application ofICG hemodynamic parameters for monitoring patients with hypertension canbe better understang high blood pressure, to identify the risk factors, and thereasonable use of antihypertensive drugs.Objective: Collect30cases in elderly patients with high blood pressurethat whose blood pressure didn′t reach the standard，Monitoring the ICG, thenaccording to the hemodynamic parameter selection adjustment ofantihypertensive drugs, the therapeutic effect was observed. Explore thehemodynamic characteristics of senile hypertension, provide the basis for elderly hypertensive patients to realize individualized treatment.Methods: Collect30subjects from the Hebei Provincial People′sHospital with uncontrolled hypertension on two antihypertensive medicationsand treated for a minimum of3months and three visits with the aid of ICG.Uncontrolled BP was defined as systolic blood pressure (SBP)≥140mmHgand/or diastolic blood pressure (DBP)≥90mm Hg. Diabetes mellitus was notpresent in any subjects.BP was measured using the oscillometric method in thesitting position after5minutes of rest. ICG was used to obtain supinehemodynamic measurements. Collect demographic information about thesubjects including age, gender, clinic visits, weight and body surface area.Each visit blood pressure and the antihypertensive drugs are accurate records.Impedance Cardiography monitoring records every stroke output (SV)/strokeoutput index (SVI), cardiac output (CO)/cardiac output index (CI), systemicperipheral vascular resistance (SVR)/systemic peripheral vascular resistanceindex (SVRI) and chest liquid volume (TFC).(table1)All the data are recorded in an Excel spreadsheet, and applying softwareSPSS13.0to statistics analysis, measurement data are presented using mean±standard deviation, we introduce the analysis of variance, X2test, multipleindependent sample nonparametric test, t test, etc. P<0.05for difference havestatistical significance.Results:1.Average age of the30subjects was84.7±3.64years, and66.7%were men. Table3summarizes the group characteristics at entry andstudy end. SBP at entry was156.17±10.38mmHg and DBP was77.33±8.01mm Hg. Subjects were on2.0±0.0antihypertensive medications at entry, with56.7%on angiotensin-converting enzyme inhibitors,43.3%on βblockers,36.7%on calcium channel blockers,30%on angiotensin II receptor blockers,and23.3%on diuretics.（Table4）.2. Subjects were treated with visit frequency at physician discretion.Eighteen subjects (60%) achieved sustained BP control to <140/90mm Hg(P<0.001) and25(83.3%) had BP <160/100mmHg. SBP was lowered19.13±10.47mmHg to137.03±16.11mm Hg (P<0.001) and DBP was lowered1.5±3.61mmHg to75.83±7.35mm Hg(P>0.05).Antihypertensiveagents increased from2.0±0.0to2.4±0.5(P<0.05), with22(73.3%) subjectsat final on angiotensin-converting enzyme inhibitors,14(46.7%) on βblockers,13(43.%) on calcium channel blockers,9(30%) on angiotensin IIreceptor blockers, and11(36.7%) on diuretics(Table4）.3. Table6compares entry and final characteristics in the group ofsubjects who achieved BP control and those who did not. At entry, there wereno statistically significant differences between the two groups, and during thestudy there were no differences in days treated or visits. Subjects whoachieved BP control had a significantly lower final SBP and SVRI, andsignificant reductions in SBP, DBP, and SVRI compared with those subjectswho did not achieve target BP(P<0.05). Subjects who did not achieve BPcontrol were on more antihypertensive medications (2.5±0.5) at study end thansubjects who did achieve BP control (2.25±0.45), the difference wasstatistically significant(P<0.05). Table Ⅵ lists the number and class ofantihypertensive agents prescribed. There were no significant differencesbetween the two groups(P>0.05).Conclusion: This study supports the feasibility of ICG as the monitoringsystem in the treatment of hypertension,the methord improved the controlrates of hypertension, ICG is a monitoring tool in antihypertensive therapy,ICG is a safe, effective and economic tool to help clinical doctors to cure thepatients as high blood pressure whose pressure difficult to control.