A kind of noninvasive continuous BP measurement methodTechnical field
The present invention relates to a kind of noninvasive continuous blood pressure assay method, and in particular to one kind is based on pulse wave translation time and biographyLead the continuous BP measurement method of ratio.
Background technology
Angiosthenia is the important physiological parameter for reflecting human circulation function, while being also clinically to diagnose the illness, observe and controlTherapeutic effect, the important evidence for carrying out Index for diagnosis.The blood pressure that noninvasive continuous BP measurement can be monitored in each cardiac cycle becomesChange, therefore noninvasive continuous BP measurement has ten in clinical monitoring of blood pressure, domestic monitoring and early warning and the monitoring of depressorDivide important meaning.
In recent years, the noninvasive continuous blood of blood pressure was calculated using the conduction time (PWTT) or conduction of velocity (PWV) of pulse wavePressure measuring method is increasingly becoming each scholar's primary study direction.The conduction time of pulse wave is that arterial pulse wave is passed from aorta petalThe time required for tip is multicast to, when calculating generally using ecg-r wave crest as starting point, synchronous pulse wave characteristic point is eventuallyPoint.Conduction of velocity is the spread speed of pulse wave in the artery.Obtaining the electrocardio of subject and pulse wave synchrodataOn the basis of, it is possible to achieve for the reckoning of blood pressure.
Existing result of study shows that systolic pressure is linear relationship with conduction time PWTT, and sets up model SBP=b1+B2*PWTT can realize noninvasive continuous blood pressure measuring.But the model is the blood pressure parameter unified model set up by different subjects, itsAccuracy is vulnerable to the influence of individual difference.
The content of the invention
In order to overcome above-mentioned technological deficiency, the present invention provides a kind of new noninvasive continuous BP measurement method, i.e., existingNew parameter-conduction ratios (dc) are introduced on the basis of blood pressure parameter model, while individually setting up personalization for each subjectBlood pressure parameter model, so that the accuracy of continuous BP measurement is significantly improved, and this method is simple and efficient, it is easy to operate, be conducive toIt is widely popularized.
To achieve these goals, the present invention is adopted the following technical scheme that：
A kind of continuous BP measurement method, comprises the following steps：
(1) synchronizing signal of the electrocardio of collection subject and pulse wave；
(2) electrocardio and the synchronizing signal of pulse wave to subject is smoothed, and detects R wave of electrocardiosignal peak value pointPosition mark is carried out with pulse wave characteristic point, the conduction ratio of the conduction time and corresponding pulse wave that obtain pulse wave is calculatedRate；
(3) conduction time and conduction ratios of gained pulse wave are brought into personalized blood pressure parameter model, calculating is obtainedThe continuous systolic pressure of subject.
The present invention introduces pulse transit ratio parameter in existing continuous BP measurement method, and set up for it is each byThe personalized blood pressure parameter model of examination person, the accuracy of measurement can be improved by methods described.
In measuring method of the present invention, the detection method of the ecg-r wave wave crest point is as follows：In collection electrocardiosignalFirst two seconds, the slope minimum value of the segment signal is obtained using algorithm, take the numerical value 0.6 times is threshold value thr, finds what is collectedLess than threshold value, itself slope, more than the point of threshold value, is starting point by the point to previous slope in electrocardiosignal, forward 20 pointsInterior maximizing point, as ecg-r wave wave crest point.
In measuring method of the present invention, the pulse wave characteristic point is main crest rising edge greatest gradient point.The arteries and veinsThe detection method of wave characteristic of fighting point is as follows：With the first ecg-r wave ripple detected in above-mentioned ecg-r wave crest point detecting methodPeak dot is starting point, and latter ecg-r wave wave crest point is terminal, and the greatest gradient for finding out pulse wave in this period clicks through rowerNote, as pulse wave characteristic point.
In measuring method of the present invention, the pulse wave translation time (PWTT) is pulse wave characteristic point and ecg-r waveThe alternate position spike of wave crest point.
In measuring method of the present invention, the pulse transit ratio (DC) is pulse wave translation time and cardiac electrical cycleRatio, i.e. DC=PWTT/T；Wherein cardiac electrical cycle (T) is time of first R ripples crest to secondary R wave crest location.
In measuring method of the present invention, the conduction ratios of the pulse wave account for the cardiac electrical cycle for pulse wave translation timeRatio.As shown in Figure 1.Cardiac electrical cycle (T) is time of first R ripples crest to secondary R wave crest location.
In measuring method of the present invention, the personalized blood pressure parameter model is set up by following methods：
(1) synchronizing signal of the electrocardio of collection subject and pulse wave, is smoothed, and detects R wave crest of electrocardiosignalValue point and pulse wave characteristic point carry out position mark, calculate the conduction of the conduction time and corresponding pulse wave that obtain pulse waveRatio；
(2) the interruption blood pressure of subject is measured, by interruption pressure value, the conduction time of gained pulse wave and conduction ratios generationEnter in basic model SBP=b1+b2 × PWTT+b3 × DC, obtain parameter b1, b2, b3, so as to set up personalized blood pressure parameter mouldType.
In measuring method of the present invention, the smoothing processing is the conventional signal processing method smothing filtering in this areaMethod.
The present invention introduces new parameter-conduction ratios in existing non-invasive blood pressure model, establishes for each testedThe personalizing parameters model of person, can obtain more accurate blood pressure result.This method is simple to operate, and accuracy is high, is clinicalMonitoring of blood pressure, domestic monitoring and early warning and the monitoring of depressor provide important evidence.
Brief description of the drawings
Fig. 1 is the calculating schematic diagram of pulse wave translation time (PWTT).
Embodiment
Following examples are used to illustrate the present invention, but are not limited to the scope of the present invention.
A kind of noninvasive continuous BP measurement method of embodiment 1
Step is as follows：
(1) synchronizing signal of the electrocardio of collection subject and pulse wave；
(2) electrocardio and the synchronizing signal of pulse wave to subject is smoothed, and detects R wave of electrocardiosignal peak value pointGone forward side by side line position tagging with pulse wave characteristic point, the conduction time that obtains pulse wave is calculated by the two alternate position spike and correspondingThe conduction ratios of pulse wave；
(3) conduction time and conduction ratios of gained pulse wave are brought into personalized blood pressure parameter model, calculating is obtainedThe continuous systolic pressure of subject.
Wherein, the personalized blood pressure parameter model is set up by following methods：
(1) blood pressure of subject is measured, and gathers the electrocardio of subject and the synchronizing signal of pulse wave, is smoothly locatedReason, detection R wave of electrocardiosignal peak value point and pulse wave characteristic point carry out position mark, calculating obtain the conduction time of pulse wave withAnd the conduction ratios of corresponding pulse wave；Repeat experiment at least three times；
(2) by gained pressure value, the conduction time of pulse wave and conduction ratios substitute into basic model SBP=b1+b2 ×In PWTT+b3 × DC, parameter b1, b2, b3 are obtained, personalized blood pressure parameter model is set up.
The detection method of the ecg-r wave wave crest point is as follows：At first two seconds of collection electrocardiosignal, it is somebody's turn to do using algorithmThe slope minimum value of segment signal, take the numerical value 0.6 times is threshold value thr, finds previous point in the electrocardiosignal collected obliqueLess than threshold value, itself slope, more than the point of threshold value, is starting point by the point to rate, forward maximizing point in 20 points, the as heartElectric R ripples wave crest point.
The pulse wave characteristic point is main crest rising edge greatest gradient point.The detection method of the pulse wave characteristic point is such asUnder：The first ecg-r wave wave crest point detected using in above-mentioned ecg-r wave crest point detecting method is starting point, latter electrocardio RRipple wave crest point is terminal, and the greatest gradient point for finding out pulse wave in this period is marked, as pulse wave characteristic point.
The pulse transit ratio (DC) is pulse wave translation time and the ratio of cardiac electrical cycle, i.e. DC=PWTT/T；Wherein cardiac electrical cycle (T) is time of first R ripples crest to secondary R wave crest location.
Method validation is tested
Pass through exercise testing measuring method more of the present invention and the accuracy of traditional noninvasive continuous BP measurement method.
The basic model of the noninvasive continuous BP measurement method of tradition is：SBP=b1+b2 × PWTT；The present invention is noninvasive continuousThe basic model of blood pressure measuring method is：SBP=b1+b2 × PWTT+b3 × DC.Exercise testing is divided into be carried out twice, is once" model experiment " of model is set up, is " examining experiment " for the second time.Quality to two kinds of measuring methods is contrasted.As a result such as table1, shown in table 2.
Wherein, error calculation formula is：
Table 1 " model experiment " mean error
As shown in Table 1, for each subject, the contraction obtained in " model experiment " using the inventive method is held upThe systolic pressure error that difference is obtained all less than existing measuring method.Wherein, the mean error obtained using the inventive method is averagedIt is worth for 4.7542mmHg, the AME 6.0120mmHg obtained less than existing measuring method.
Table 2 " examining experiment " mean error
As shown in table 2, in " examining experiment ", the systolic pressure error obtained using the method for the invention is most of all smallThe systolic pressure error obtained in existing measuring method.Wherein, the mean error average value that the method for the invention is obtained is5.8646mmHg, the mean error average value 7.0066mmHg obtained less than existing measuring method.
The T assays of table 3
| Group | H | P | Conventional method average value | The inventive method average value |
| " model experiment " | 1 | 0.0076 | 6.0120 | 4.7542 |
| " examining experiment " | 1 | 0.0289 | 7.0066 | 5.8646 |
As shown in table 3, T inspections are carried out using matlab programmings to the result of " model experiment ", as a result (received for H=1Assuming that), P=0.0076<α=0.05, illustrates that two grouping error discriminations are very high, with significant difference.Pass through " model experiment "The average value of mean error compares, and the result that T is examined can determine systolic pressure of the method for the invention than existing methodError is small.Similarly, same conclusion is also obtained for " examine and test ".
Comprehensive " model experiment " and the comparative result of the mean error average value of " examine and test ", and T inspections twiceAs a result, we may safely draw the conclusion：Measuring method of the present invention compares the measuring method of existing single parameter in accuracy sideFace obtains very big raising.
Although above the present invention is described in detail with a general description of the specific embodiments,On the basis of the present invention, it can be made some modifications or improvements, this will be apparent to those skilled in the art.CauseThis, these modifications or improvements, belong to the scope of protection of present invention without departing from theon the basis of the spirit of the present invention.