Apparatus and method of measuring blood pressure

Abstract

Provided is a blood pressure measuring apparatus including: a pressurizing unit applying pressure to a blood vessel according to a first condition or a second condition; a pressure sensor sensing a sphygmus wave and a pressure of the blood vessel from the blood vessel under the first condition or the second condition; a standard blood pressure calculating unit for calculating a systolic standard blood pressure and a diastolic standard blood pressure; a continuous blood pressure calculating unit for calculating continuous blood pressure; and a repressurizing determining unit for determining whether pressure is applied to the blood vessel under the second condition during measuring of continuous blood pressure.

1 . An apparatus for measuring blood pressure comprising:
 a pressurizing unit for applying pressure to a blood vessel of an examinee according to a first condition or a second condition;   a pressure sensor for sensing a sphygmus wave and a pressure of the blood vessel under the first condition or the second condition;   a standard blood pressure calculating unit for calculating a systolic standard blood pressure and a diastolic standard blood pressure of the examinee based on the sphygmus wave and the blood vessel pressure sensed by the pressure sensor under the first condition;   a continuous blood pressure calculating unit for calculating continuous blood pressure of the examinee based on the sphygmus wave and the blood vessel pressure sensed by the pressure sensor under the second condition and based on the systolic standard blood pressure or the diastolic standard blood pressure; and   a repressurizing determining unit for determining whether pressure applied to the blood vessel during measuring of continuous blood pressure deviates from the second condition,   wherein when the repressurizing determining unit determines that pressure applied to the blood vessel of the examinee deviates from the second condition, the pressurizing unit applies pressure to the blood vessel of the examinee again under the second condition.   
   
   
       2 . The apparatus of  claim 1 , wherein the first condition is an increased pressure condition under which the pressure is increased at a uniform pressure variation rate to apply pressure to the blood vessel, or a reduced pressure condition under which pressure applied to the blood vessel is reduced at a uniform pressure variation rate after pressure is applied to the blood vessel to block the blood vessel. 
   
   
       3 . The apparatus of  claim 1 , wherein the second condition is a fixed pressure condition under which a uniform pressure is applied to the blood vessel of the examinee without completely blocking the blood vessel. 
   
   
       4 . The apparatus of  claim 3 , wherein if a difference between an amplitude of a baseline of a sphygmus wave sensed at a first time after starting the measurement of continuous blood pressure and an amplitude of a baseline of a sphygmus wave sensed of a second time later than the first time reaches at least a first criterion, and a ratio of a pulse amplitude of a sphygmus wave at the first time to a pulse amplitude of the sphygmus wave at the second time is less than or equal to a second criterion, the repressurizing determining unit determines that pressure applied to the blood vessel of the examinee deviates from the second condition. 
   
   
       5 . The apparatus of  claim 3 , wherein if a difference between an amplitude of a baseline of a sphygmus wave sensed at a first time after starting the measurement of continuous blood pressure and an amplitude of a baseline of a sphygmus wave sensed of a second time later than the first time reaches at least a first criterion, and a ratio of a pulse amplitude of a sphygmus wave at the first time to a pulse amplitude of the sphygmus wave at the second time is greater than a second criterion, the repressurizing determining unit determines that pressure applied to the blood vessel of the examinee satisfies the second condition. 
   
   
       6 . The apparatus of  claim 4 , wherein the first criterion is a value corresponding to a pressure difference of 5 mmHg. 
   
   
       7 . The apparatus of  claim 4 , wherein the second criterion is 80%. 
   
   
       8 . The apparatus of  claim 5 , wherein the first criterion is a value corresponding to a pressure difference of 5 mmHg. 
   
   
       9 . The apparatus of  claim 5 , wherein the second criterion is 80%. 
   
   
       10 . The apparatus of  claim 1 , further comprising an applied pressure determining unit for determining the second condition for measuring continuous blood pressure such that an applied pressure under the second condition is less than the diastolic standard blood pressure. 
   
   
       11 . The apparatus of  claim 10 , wherein a value less than or equal to 80% of the diastolic standard blood pressure is determined as the applied pressure under the second condition. 
   
   
       12 . The apparatus of  claim 10 , wherein the applied pressure under the second condition is less than or equal to a pressure at which an inflection point of an envelope line occurs and wherein the envelope line is formed by connecting high peaks of the sphygmus wave sensed by the pressure sensor under the first condition. 
   
   
       13 . An apparatus for measuring blood pressure comprising:
 a pressurizing unit for applying pressure to a blood vessel of an examinee according to a first condition or a second condition;   a pressure sensor for sensing a sphygmus wave and the pressure of the blood vessel under the first condition or the second condition;   a standard blood pressure calculating unit for calculating a systolic standard blood pressure and a diastolic standard blood pressure of the examinee based on the sphygmus wave and the blood vessel pressure sensed by the pressure sensor under the first condition;   an applied pressure determining unit for determining an applied pressure under a second condition for measuring continuous blood pressure; and   a continuous blood pressure calculating unit for calculating continuous blood pressure of the examinee based on a sphygmus wave and the blood vessel pressure sensed by the pressure sensor while applying the determined applied pressure to the blood vessel under the second condition and based on the systolic standard blood pressure and the diastolic standard blood pressure.   
   
   
       14 . The apparatus of  claim 13 , wherein the applied pressure under the second condition is less than or equal to 80% of the diastolic standard blood pressure. 
   
   
       15 . The apparatus of  claim 13 , wherein the applied pressure under the second condition is less than the diastolic standard blood pressure. 
   
   
       16 . The apparatus of  claim 13 , wherein the applied pressure under the second condition is less than or equal to a pressure at which an inflection point of an envelope line occurs and, wherein the envelope line is formed by connecting high peaks of the sphygmus wave sensed by the pressure sensor under the first condition. 
   
   
       17 . A method of measuring blood pressure, the method comprising:
 applying pressure to a blood vessel of an examinee under a first condition for measuring a standard blood pressure;   calculating standard systolic and diastolic standard blood pressures of the examinee based on a sphygmus wave and the blood vessel pressure sensed while applying pressure to the blood vessel under the first condition;   applying pressure to the blood vessel under a second condition for measuring continuous blood pressure;   measuring continuous blood pressure of the examinee based on a sphygmus wave and the blood vessel pressure of the examinee sensed while applying pressure to the blood vessel under the second condition, and based on the systolic and diastolic standard blood pressures;   determining whether to reapply pressure by determining whether pressure applied to the blood vessel of the examinee during the measuring of continuous blood pressure deviates from the second condition; and   reapplying pressure to the blood vessel of the examinee under the second condition when it is determined that pressure applied to the blood vessel of the examinee during the meaning of continuous blood pressure deviates from the second condition.   
   
   
       18 . The method of  claim 17 , wherein the first condition is an increased pressure condition under which the pressure is increased at a uniform pressure variation rate to pressurize the blood vessel, or a reduced pressure condition under which pressure applied to the blood vessel is reduced at a uniform pressure variation rate after pressure is applied to the blood vessel to block the block vessel. 
   
   
       19 . The method of  claim 17 , wherein the second condition is a fixed pressure condition under which a uniform pressure is applied to the blood vessel of the examinee without completely blocking the blood vessel. 
   
   
       20 . The method of  claim 19 , wherein it is determined that pressure applied to the blood vessel of the examinee deviates from the second condition, if a difference between an amplitude of a baseline of the sphygmus wave sensed at a first time after starting the measurement of continuous blood pressure and an amplitude of a baseline of the sphygmus wave sensed at a second time later than the first time reaches at least a first criterion, and a ratio of a pulse amplitude of the sphygmus wave at the first time to a pulse amplitude of the sphygmus wave at the second time is less than or equal to a second criterion. 
   
   
       21 . The method of  claim 20 , wherein the first criterion is a value corresponding to a pressure difference of 5 mmHg. 
   
   
       22 . The method of  claim 20 , wherein the second criterion is 80%. 
   
   
       23 . The method of  claim 17 , further comprising determining the applied pressure under the second condition to be less than the diastolic standard blood pressure. 
   
   
       24 . The method of  claim 23 , wherein the applied pressure under the second condition is less than or equal to 80% of the diastolic standard blood pressure. 
   
   
       25 . The method of  claim 23 , wherein the applied pressure under the second condition is less than or equal to a pressure at which an inflection point of an envelope line occurs and, wherein the envelope line is formed by connecting high peaks of the sphygmus wave sensed under the first condition. 
   
   
       26 . A method of measuring blood pressure, the method comprising:
 applying pressure to a blood vessel of an examinee under a first condition for measuring a standard blood pressure;   calculating systolic and diastolic standard blood pressures of the examinee based on a sphygmus wave and the blood vessel pressure sensed while applying pressure to the blood vessel under the first condition   determining a second condition for measuring continuous blood pressure such that an applied pressure under the second condition is a value less than the diastolic standard blood pressure   applying the determined applied pressure to the blood vessel under the second condition; and   measuring continuous blood pressure of the examinee based on a sphygmus wave and the blood vessel pressure of the examinee sensed while applying the determined applied pressure to the blood vessel under the second condition, and based on the systolic and diastolic standard blood pressures.   
   
   
       27 . The method of  claim 26 , wherein the applied pressure under the second condition is determined to be a value less than or equal to 80% of the diastolic standard blood pressure. 
   
   
       28 . The method of  claim 26 , wherein the applied pressure under the second condition is less than or equal to a pressure at which an inflection point of an envelope line occurs and, wherein the envelope line is formed by connecting high peaks of the sphygmus wave sensed by the pressure sensor under the first condition.