P-286 Non-Invasive Evaluation of Aortic Blood Flow in Normal Taiwanese

Abstract

Background: Functional status of heart is important in patients with circulatory instability. However, currently, measurements of cardiac function often need invasive methods such as Swan-Ganz catheterization or heavy machine such as a full-scale ultrasonoscope. Materials and Methods: During a 2 mouths period, we evaluated the aortic flow using a dedicated Doppler ultrasonometer which is non-invasive and can be performed conveniently and portably on the bedside. A total of 100 persons were recruited for recording of aortic blood flow. The machine automatically analyzes aortic flow waveforms to generate peak velocity (VPK) peak, velocity time interval (VTI), heart rate (HR), stroke volume (SV), cardiac output (CO) and cardiac index (CI). Results: The age of examined subjects ranged from 1 month to 62 years old, the height (Ht) ranged between 57 and 181 cm. The weight (Wt) between 4.2 and 106 kg, the calculated body surface area (BSA) ranged between 0.27 and 2.3 cm2. The regression analysis for various indices were listed as follows: Index Y = K (constant) +b (slope) × Index X: VPK = 1.5049 + 0.0028×Wt; VPK = 1.592 + 0.0015×Ht; VPK = 1.5477 + 0.1284×BSA; SV = 35.905 + 0.7856×Wt; SV = 31.384 + 0.7169×Ht; SV = 16.308 + 41.161×BSA; CO = 0.0396 + 3.399×Wt; CO = 0.0367 + 0.071×Ht; CO = 2.3948 + 2.0859×BSA. Conclusion: Our experience showed cardiac function can be obtained conveniently and non-invasively using a dedicated portable meter. We also demonstrate that peak aortic blood flow velocity is almost a constant through human ages, while cardiac output increased with progressive increase in individual size.