Kubicek 氏于1966年将心阻抗图用于测量人体心排血量等血流动力学变数以来,引起众多学者关注。我国沈氏、邓氏也相继报导认为这项技术具无损伤性,重复性强等特点。本文旨在阐述心阻抗图测算问题。一、Kubicek 公式及其它变异公式:Kubicek 等将胸腔与主动脉看成是两个同心园园桶模型,心脏射血时主动脉截面积发生变化,引起阻抗变化,据此推导出Kubicek 公式:△V=(PL~2/Z_0~2)△Z_0于1070年又将微分图引入公:△Z=dz/dt min·T,SV=P(L~2/Z_0~2)·(dz/dt)min·T_0(Sv:心搏血量,T:射血时间,1:常采用135～140Ωm)此公式已为临床广泛应用。但此式中 Z_0是个变量,常受呼吸、电极距离、胸腔积液、肺水肿等因素影响。为了消除 Z_0影响,金井宽提出不用 Z_0的导纳计测心搏血量理论。导纳(Y)为 Z 的倒数,△V=P_1L~2△Y 代入 Kubicek公式:Sv=P_1L~2·(dz/dt)min·T。伊藤等又将导纳图应用到临床,从而使阻抗图计算可靠性有所提高。山越等又研制出了连续导纳测定装置。1980年小笠原在犬试验中指出:按 Kubicek 公式 Since Kubicek’s heart impedance plot was used to measure hemodynamic variables such as cardiac output in 1966, many researchers have been concerned. China’s Shen, Deng have also reported that this technology is non-invasive, repetitive and so on. This article aims to elaborate on the heart impedance graph measurement problem. First, Kubicek formula and other mutation formulas: Kubicek and other thoracic cavity and aorta as two concentric garden pavilion model, aortic cross-sectional area of ​​cardiac ejection changes, causing impedance changes, thus derived Kubicek formula: △ V = (PL ~ 2 / Z_0 ~ 2) △ Z_0 In 1070, the differential graph was again introduced to the public: ΔZ = dz / dt min · T, SV = P (L ~ 2 / Z_0 ~ 2) · (dz / dt ) min · T_0 (Sv: stroke blood volume, T: ejection time, 1: often use 135 ~ 140Ωm) This formula has been widely used in clinical. However, this formula is a variable Z_0, often affected by breathing, electrode distance, pleural effusion, pulmonary edema and other factors. In order to eliminate the influence of Z_0, Kanei Kawai proposed not to use Z_0 admittance measurement of stroke volume theory. Admittance (Y) is the reciprocal of Z, △ V = P_1L ~ 2 △ Y into Kubicek formula: Sv = P_1L ~ 2 · (dz / dt) min · T. Ito and then admittance map applied to the clinical, so that the reliability of the impedance map has improved. Mountain Yue and developed a continuous admittance measurement device. In 1980, Ogasawara pointed out in a dog test: according to Kubicek’s formula