Autonomic nervous activity monitor, blood processing apparatus, blood collecting apparatus and autonomic nervous activity monitoring method
View Patent ↗An autonomic nervous activity monitor capable of predicting occurrence of abnormal reaction depending on autonomic nervous activity and used for medical practice and the like is provided. A blood component collecting apparatus 100 carries out frequency analysis to a pattern of heartbeat which is acquired by an ECG 300 from a donor, and calculates a high frequency component value [msec 2 ] defined as an indicator for parasympathetic activity and a ratio value of a low frequency component to the high frequency component defined as an indicator for sympathetic activity to detect a change in these values on a time-series base. When a judgment circuit 204 predicts that abnormal reaction may occur to a donor after blood collection operation is started, a controller 200 controls a pump 9 to decrease a blood drawing or blood returning speed, or, to stop blood drawing or blood returning operation.
1. An autonomic nervous activity monitoring method for predicting whether abnormal reaction may occur to a body, comprising the steps of:
measuring heartbeat or pulse of a body to acquire a pattern of the heartbeat or pulse as biological information;
calculating a value [msec 2 ] of a high frequency component (a HF value) defined as an indicator for parasympathetic activity and a value of a ratio of a low frequency component (LF) to the high frequency component (a LF/HF ratio value) defined as an indicator for sympathetic activity on a time-series base by carrying out frequency analysis to the acquired pattern of the heartbeat or pulse; and
predicting whether abnormal reaction may occur to the body from a predetermined relationship between the HF value and the LF/HF ratio value, based upon the calculated HF values and the calculated LF/HF ratio values;
wherein, when alpha is defined as a predetermined coefficient, the predicting step predicts that abnormal reaction may occur to the body when the calculated HF value exceeds a predetermined reference value, and, when a sum of a period of {(the calculated HF value)>(the coefficient alpha)×(the calculated LF/HF ratio value)} becomes not less than 10% of a calculation period in the calculating step.
2. An autonomic nervous activity monitoring method according to claim 1 , wherein the predetermined reference value ranges from 100 to 1000 [msec 2 ], the coefficient alpha ranges from 10 to 100 and the calculation period ranges from 2 to 10 [min].
3. An autonomic nervous activity monitoring method according to claim 1 , wherein, when beta is defined as a predetermined coefficient, the predicting step predicts that abnormal reaction may occur to the body when a sum of a period of {(the calculated HF value)>(the coefficient beta)×(the calculated LF/HF ratio value)} becomes not less than 10% of a calculation period in the calculating step.
4. An autonomic nervous activity monitoring method according to claim 3 , wherein the coefficient beta ranges from 25 to 500 and the calculation period ranges from 2 to 10 [min].
5. An autonomic nervous activity monitoring method according to claim 1 , wherein, when alpha is defined as a predetermined coefficient and beta is defined as a predetermined coefficient which is larger than the coefficient alpha, the prediction unit predicts that abnormal reaction may occur to the body when the HF value calculated by the calculation unit exceeds a predetermined reference value and when a sum of a period of {(the HF value calculated by the calculation unit)>(the coefficient alpha)×(the LF/HF ratio value calculated by the calculation unit)} becomes not less than 10% of a calculation period carried out by the calculation unit, or, when a sum of a period of {(the HF value calculated by the calculation unit)>(the coefficient beta)×(the LF/HF ratio value calculated by the calculation unit)} becomes not less than 10% of the calculation period carried out by the calculation unit.
6. An autonomic nervous activity monitoring method according to claim 5 , wherein the predetermined reference value ranges from 100 to 1000 [msec 2 ], the coefficient alpha ranges from 10 to 100, the coefficient beta ranges from 25 to 500 and the calculation period ranges from 2 to 10 [min].