PULSE ACTIVITY INDICATOR

• US 3,841,314 A
• Filed: 07/16/1973
• Issued: 10/15/1974
• Est. Priority Date: 07/16/1973
• Status: Expired due to Term

• Current Assignee: Robert E. Page
• Original Assignee: Robert E. Page
• Inventors: Page, Robert E.
• Primary Examiner(s): Kamm, William E.
• Application Number:
  US05/379,508
• Time in Patent Office: 456 Days
• Field of Search: 128/2L,2.5A,2.5M,2.5P,2.5Q,2.5R,2.5T,2.6E,2.6F,2.6R
• US Class Current: 600/479
• CPC Class Codes: A61B 5/02 Detecting, measuring or recording pulse, heart rate, blood pressure or blood flow; Combined pulse/heart-rate/blood pressure determination; Evaluating a cardiovascular condition not otherwise provided for, e.g. using combinations of techniques provided for in this group with electrocardiography or electroauscultation; Heart catheters for measuring blood pressure
• CPC Class Codes: A61B 5/02255 the pressure being controlled by plethysmographic signals, e.g. derived from optical sensors
• CPC Class Codes: A61B 5/02416 using photoplethysmograph signals, e.g. generated by infrared radiation A61B5/14552 takes precedence
• CPC Class Codes: A61B 5/30 Input circuits therefor
• CPC Class Codes: A61B 5/308 for electrocardiography [ECG]

Abstract

A cardiovascular monitoring system employs a photoelectric monitoring circuit to obtain analog signals corresponding to the heartbeat of a subject. Cooperating amplification and detecting circuitry provide an audible tone corresponding to each pulse beat as well as a readout of the pulse rate of the subject and blood pressure. Circuitry is provided which detects and displays both systolic and diastolic blood pressure. Additionally, an auxiliary input permits selection of the subject'"'"''"'"'s pulse at separate points. Circuitry providing a simultaneous output for additional electro-physiological measurement, such as electrocardiograph instrumentation, is also included.

Claims

1. A cardiovascular instrumentation system for measuring cardiovascular activity having a plurality of positive peaks comprising:

sensor means for generating an electrical analog signal of cardiovascular activity of a living subject;

a linear amplifier connected to said sensor means for increasing the power of said electrical analog signal;

first logic circuit means connected to said linear amplifier for producing a digital pulse signal having a pulse duration corresponding to the time of cardiovascular activity;

second logic circuit means connected to said first logic circuit means for producing a digital signal having a pulse duration corresponding to the length of time from the initiation of the cardiovascular activity to the first peak thereof;

a first measuring circuit means connected to said second logic circuit and to said linear amplifier for measuring the value of said amplified cardiovascular analog signal in response to the output of said second logic circuit means and connected to said first logic circuit means for enabling said first measuring circuit means to measure succeeding pulses;

a first display means connected to said first measuring for providing an indication of the measured value;

third logic circuit means connected to said first logic circuit means for generating a digital signal having a pulse duration corresponding to the length of time from the initiation of the cardiovascular activity to a second peak thereof;

a second measuring circuit means connected to said third logic circuit and to said linear amplifier for measuring the value of said amplified cardiovascular analog signal in response to the output of said third logic circuit means and connected to said first logic circuit means for enabling said second measuring circuit means to measure succeeding pulses;

a second display means connected to said second measuring circuit means for providing an indication of the measured value;

a stabilized voltage source;

a trigger generator circuit connected to said first logic circuit means for generating a pulse in response thereto;

a first switch means connected to said trigger generator circuit and to said stabilized voltage source for timely switching said voltage in response to the trigger pulse;

a capacitor connected to said first switch to be charged to the stabilized voltage upon operation of said first switch means;

a plurality of resistances connected to said capacitor to serve as a discharge path therefor;

a plurality of switch means, each connected to one of said plurality of resistances and effectively connected to said capcitor to complete the discharge path; and

fourth logic circuit means connected between said trigger circuit means and said plurality of switches for sequential energization of each switch.

2. A cardiovascular instrumentation system according to claim 1 wherein said sensor means includes:

a receptacle configured for receiving a part of the anatomy of the test subject;

light source means mounted on one wall of said receptacle for emitting light energy for impinging the part of the anatomy of the test subject engaged therebetween;

photo-electric detector means mounted on the opposite wall of said receptacle from said light source electrically connected to said linear amplifier means and positioned to intercept the light energy passing through the engaged part of the anatomy of the test subject;

secondary electrophysiological detector means carried by a wall of said receptacle and configured to contact the engaged part of the anatomy of the test subject;

amplifier means electrically connected to said secondary electrophysicalogical detector means for increasing the detected signal means; and

connector means electrically connected to said amplifier means for cooperatively coupling said amplified signal to an external indicator for simultaneous inspection thereof with the measured value of the cardiovascular activity displayed by the aforesaid first and second display means.

3. A cardiovascular instrumentation system according to claim 1 in which said fourth logic circuit means includes:

a plurality of monostable multivibrator circuits each connected to one of the plurality of switch means except the last switch means and series connected to each other for sequential operation in response to the aforedescribed trigger pulse; and

fifth logIc circuit means connected to said plurality of series connected monostable multivibrator means, and connected to the aforesaid first logic circuit means, and connected to the last of said plurality of switch means for actuating said last switch means in response to the absence of any of the outputs from said plurality of monostable multivibrator means, and the presence of an output from said logic circuit means.

4. A cardiovascular instrumentation system according to claim 3 in which said first logic circuit means includes a zero-crossing detector.

5. A cardiovascular instrumentation system according to claim 4 in which said second logic circuit includes a monostable multivibrator.

6. A cardiovascular instrumentation system according to claim 5 in which said third logic circuit means includes a monostable multivibrator.

7. A cardiovascular instrumentation system according to claim 6 in which said first and second measuring circuit means are sample-hold analog voltmeter circuits.