| 摘要 |
<p>PURPOSE:To measure blood pressure with good accuracy without being affected by the variation of cuff pressure immediately after pressure reduction, by calculating a pulse wave amplitude value at every one beat of a pulse wave and determining a blood pressure value from the change in said pulse wave amplitude value. CONSTITUTION:When the pressurization objective value suitable for an examinee is set by a pressurization setting SW 16 and a start SW 15 is turned ON, a pump 6 starts the pressurization of a cuff 2 by the instruction of a CPU 11. When cuff pressure P reaches the pressurization objective value, the counter contained in the CPU 11 performs the sampling of a count value. The time differential value Dn at a time tn is calculated from the cuff pressure instantaneous value Pn at the stop time of counting. A peak point D* and a rising point D<+> are extracted and, by taking the difference between both points, a pulse wave differential amplitude value Dp is extracted and the max. value Dpmax is extracted from the envelope of the row of the differential amplitude value Dp. Then, the max. and min. blood pressure values are calculated from the cuff pressures corresponding to the differential amplitude values Dps, Dpd calculated before and after the appearance of the max. value Dpmax. Therefore, the effect of the variation in the cuff pressure immediately after pressure reduction can be reduced.</p> |
