Patent Application
20050078533
The invention relates to systems used for physiological data acquisition. It also relates to diagnostic systems.
Phonocardiogram recording involves an acoustic sensor placed on a patient's chest and a recording unit. The U.S. Pat. No. 5,213,108 to Mark S Bredesen discloses a visual display stethoscope for use in the auscultation of body sounds. The stethoscope chest piece and recording/visualization unit are physically separated and have to be held by both hands. The chest piece has to be pressed against the patient's chest by one hand while the recording/visualizsation unit has is held in the other hand. The procedure is quite cumbersome.
The problem of sensors application exacerbates when more than one sensor have to be applied concurrently. U.S. Pat. Nos. 5,165,417, 5,844,997, 6,139,505, 6,394,967 to Raymond Murphy, the inventor herein, disclose multichannel sound recording system. The U.S. Pat. No. 5,844,997 to Raymond Murphy discloses method and apparatus for locating the origin of intrathoracic sounds when sounds on the chest are recorded with 5 or more acoustic sensors applied concurrently. Application of multiple sensors to a patient's chest is a challenging problem. All sensors have to endure right amount of pressure against the skin. The pressure is normally provided by the operator's hands. The sensors are wired to the computer. The wires reduce the patient mobility and interfere with EKG leads and intravenous lines. Finally, operation of the computer located away from the patient and simultaneously pressing sensors against the patient's chest is difficult for a single person to accomplish.
The invention disclosed herein simplifies application of physiological sensors. In the preferred embodiment, referred hereafter as “EKG Stethoscope”, the disclosed system is used to simultaneously record the audio signal from an acoustic sensor and the corresponding electrical EKG signal from EKG electrodes. In other words, the EKG Stethoscope allows the medical practitioner to perform auscultation and obtain electrocardiographic signal at the same time.
The EKG Stethoscope has the following advantages:
In an alternative preferred embodiment the plurality of acoustic sensors are physically attached to the back of a PDA. An operator presses the PDA single-handedly against patient's chest in such a manner that sensors are in contact with the patient's skin and the PDA display faces the operator. The physiological acoustic signal is converted by the sensors into an electrical signal that is transmitted into the PDA. The PDA automatically analyzes the sound and localizes the origin of the sound. The PDA visualizes the sound waveform, marks sound features and visualizes sound origin on the computer's display. Further, sound from one sensor is amplified and transmitted to operator's headphones for simultaneous auscultation. Concurrent audio and visual experience greatly enhances the operator's ability to diagnose lung and heart disease. The operator looks at the PDA display for cues on abnormal sound intrathoracic location and sound characteristics. The device can characterize abnormal heart sounds such as murmurs and indicate murmur location within the heart. The device can also characterize abnormal lung sounds such as wheezes and crackles and indicate their location within the lungs.
Users working in noisy environments have difficulty with normal stethoscopes. This invention provide important sound information is such noisy environments.
The pocket computer 201 of the EKG Stethoscope can be a PDA such as Compaq iPAQ5450 Pocket PC. The electrical signal from both acoustic and EKG sensors is transmitted to the PDA's serial or analog input ports. The transmission can be via wires or wirelessly. The PDA is programmed to display the EKG waveform 203 and Phonocardiogram 204 on its screen 202 and store the data for later retrieval/transfer. Also, the PDA can be programmed to perform the automatic analysis of the EKG and acoustic signals.
The pocket computer 301 of the multichannel sound analyzer can be a PDA such as a Compaq iPAQ5450 Pocket PC. The electrical signal from the acoustic sensors is transmitted to the PDA's serial or analog input ports. The transmission can be via wire or wirelessly. The PDA is programmed to display the acoustic waveforms 303 and sound source location 304 on its screen 302 and to store the data for later retrieval/transfer. Also, the PDA can be programmed to perform the automatic analysis of the acoustic signals.
