Body-worn vital sign monitor
The invention provides a body-worn monitor featuring a processing system that receives a digital data stream from an ECG system. A cable houses the ECG system at one terminal end, and plugs into the processing system, which is worn on the patient's wrist like a conventional wristwatch. The ECG system features: i) a connecting portion connected to multiple electrodes worn by the patient; ii) a differential amplifier that receives electrical signals from each electrode and process them to generate an analog ECG waveform; iii) an analog-to-digital converter that converts the analog ECG waveform into a digital ECG waveform; and iv) a transceiver that transmits a digital data stream representing the digital ECG waveform (or information calculated from the waveform) through the cable and to the processing system. Different ECG systems, typically featuring three, five, or twelve electrodes, can be interchanged with one another.
1. A system for monitoring a patient, comprising:
a processing system configured to be worn on a patient's body and comprising a processor in electrical communication with a first serial transceiver configured to receive a digital data stream via a protocol from a cable comprising an ECG system at a first terminal end of the cable and integrated with the cable and a second connector at a second terminal end of the cable configured to removably connect to the first connector,
the ECG system comprising: i) a connecting portion configured to connect to a plurality of electrodes configured to be worn on the patient; ii) a differential amplifier configured to receive electrical signals from each of the plurality of electrodes and process them to generate an analog ECG waveform; iii) an analog-to-digital converter configured to convert the analog ECG waveform into a digital ECG waveform; and iv) a first transceiver component configured to transmit a first digital data stream representing the digital ECG waveform or information calculated therefrom through the cable and to the processing system via the protocol: and
a motion-detecting sensor comprising an accelerometer operably connected to a second transceiver component and configured to generate a digital motion waveform comprising data indicative of motion of the body part to which the motion-detecting sensor is attached and transmit a second digital data stream representing the digital motion waveform or information calculated therefrom through the cable and to the processing system via the serial protocol,
wherein the processing system is configured to synchronize data transmission from the first and second transceiver components operably connected to the processor via the first connector, and
wherein the serial transceiver is a CAN transceiver, the serial protocol is a CAN protocol, and the serial transceiver is configured to transmit a digital data stream according to the CAN protocol.
2. The system of claim 1 , wherein the cable comprises a housing at its terminal end that encloses the ECG system.
3. The system of claim 2 , wherein the housing further comprises the motion-detecting sensor.
4. The system of claim 3 , wherein the motion-detecting sensor is an accelerometer.
5. The system of claim 2 , wherein the housing further comprises a temperature sensor.
6. The system of claim 5 , wherein the temperature sensor is a thermocouple.
7. The system of claim 1 , wherein the first digital data stream and the second digital data stream are each transmitted to the processing system over a common data transmission line within the cable.
8. The system of claim 7 , wherein the first digital data stream comprises a first header portion and a first data portion, the first header portion indicating that the first data portion comprises ECG information.
9. The system of claim 8 , wherein the first data portion comprises information indicating one of an ECG waveform, heart rate, an error code, and a physiological state corresponding to the patient.
10. The system of claim 7 , wherein the second digital data stream comprises a second header portion and a second data portion, the second header portion indicating that the second data portion comprises motion information.
11. The system of claim 10 , wherein the second data portion comprises information indicating one of an ACC waveform, degree of motion, posture, and an activity level.
12. The system of claim 1 , wherein the ECG system further comprises a system for measuring respiratory rate from the patient.
13. The system of claim 12 , wherein ECG information comprises respiratory rate calculated from the digital ECG waveform.
14. The system of claim 1 , wherein the processing system further comprises a display configured to render ECG information.
15. The system of claim 14 , wherein the display is further configured to render at least one of heart rate and an ECG waveform.
16. The system of claim 1 , wherein the ECG system is a single integrated circuit.
17. The system of claim 1 , wherein the ECG system connects to one of three, five, and twelve electrodes.