Patent ID: 6491638
Filing Date: 2002-12-10
Classification: A61B

Abstract:
An apparatus for monitoring a condition of blood circulation of a living subject, comprising:a heartbeat-synchronous-wave detecting device which detects a heartbeat-synchronous wave from the subject; an arrhythmia judging means for judging whether an arrhythmia has occurred to the subject, based on the heartbeat-synchronous wave detected by the heartbeat-synchronous-wave detecting device; a first blood-pressure determining means including an inflatable cuff which is adapted to be wound around a first body portion of the subject to occlude an artery of the first body portion, the first blood-pressure determining means determining at least one first blood pressure of the subject based on a first pulse wave which is produced in the cuff when a pressure in the cuff is decreased; a blood-pressure-relating-information obtaining means including at least one pulse-wave detecting device which is adapted to be worn on at least one second body portion of the subject to detect at least one second pulse wave from the at least one second body portion without occluding at least one artery of the at least one second body portion, the blood-pressure-relating-information obtaining means iteratively obtaining, based on the at least one second pulse wave detected by the at least one pulse-wave detecting device, a piece of blood-pressure-relating information which changes in relation with blood pressure of the subject; a relationship determining means for determining a relationship between blood pressure and blood-pressure-relating information, based on at least one first blood pressure value determined by the first blood-pressure determining means and at least one piece of blood-pressure-relating information obtained by the blood-pressure-relating-information obtaining means; a second blood-pressure determining means for iteratively determining, according to the relationship determined by the relationship determining means, a second blood pressure of the subject based on each of the pieces of blood-pressure-relating information iteratively obtained by the blood-pressure-relating-information obtaining means; a change-value calculating means for calculating a change value of each of the second blood pressure values iteratively determined by the second blood-pressure determining means; and an abnormality judging means for judging that the condition of blood circulation of the subject is abnormal, when the arrhythmia judging means judges that the arrhythmia has occurred to the subject and when the change value calculated by the change-value calculating means does not fall within a first reference range.