Method for recording an electrocardiogram

Information

  • Patent Grant
  • 4848350
  • Patent Number
    4,848,350
  • Date Filed
    Monday, October 24, 1988
    37 years ago
  • Date Issued
    Tuesday, July 18, 1989
    36 years ago
  • Inventors
  • Examiners
    • Hindenburg; Max
    • Citrin; Randy
    Agents
    • Horn; Spensley
Abstract
Disclosed is a system, apparatus and method for gathering physiological data. Basic to the system of the present invention is a rigid body mold having preferably a negative impression of the dorsal half of the body. By connecting and/or embedding sensors to the body mold at specific locations, e.g., accelerometers, thermistors, and electrocardiogram electrodes, the sensors will be accurately and reproducibly positioned next to a specific body location each time the subject lies in the body mold. The body mold can be used to insulate the body from external motions thereby facilitating the preparation of a ballistocardiogram. The exact re-positioning of the body in the mold allows exact determination of the center of gravity in the horizontal plane of the body.
Description
Claims
  • 1. A method for recording an electrocardiogram comprising the steps of:
  • embedding electrocardiogram electrodes in the body mold
  • placing a body in a substantially rigid body mold having an impression intimately matching the entire length of the dorsal portion of the body, whereby the substantial rigidity of the body mold holds the electrocardiogram electrodes in proximal contact with the body; and
  • recording the amplified electrode voltage of the electrocardiogram electrodes.
  • 2. The method of claim 1 wherein the placing step comprises first laying the subject on a thin, flexible sheet, and then lowering the sheet bearing the subject into the impression.
Parent Case Info

This is a continuation of application Ser. No. 07/073,630 filed on July 15, 1987, abandoned which is a division of application Ser. No. 06/786,746 filed on Oct. 11, 1985, abandoned. 1. Field of the Invention The present invention relates to the field of medical instrumentation and methods of using such instrumentation in an accurate and reproducible manner. In particular the present invention concerns use of gravity and a body mold of a subject to facilitate use of sensors to gather physiological data. 2. Prior art To measure physiological conditions, electronic or other types of sensors are often used to gather desired physiological data. For example, to estimate temperature, a thermistor can be used. And to estimate the volume of blood passing through the heart in a given period of time, an accelerometer can be used. Other examples of sensors are commonly known and include without limitation an electrocardiogram electrode and a stethoscope metal bell end piece. For other examples see U.S. Pat. Nos. 3,910,257 and 4,129,125. See also Ballistocardiography and Cardiovascular Therapy, Proceedings of the Second World Congress on Ballistocardiography Cardiovascular Dynamics, Oporto 1969, pages 343-353 (N.Y., 1970). To use some of the electronic sensors mentioned above, the sensor is typically strapped, suction-cupped or otherwise affixed directly to the human body at desired specific body locations. See for example U.S. Pat. No. 3,910,257. It is obviously important to firmly position the electrodes and sensors in an exact location on the patient to reduce the chances of error and to attempt to achieve reproducible results. However, due to the typical methods of sensor affixation, the data obtained is often irreproducible as it is not readily possible to locate the sensor in the same place on the body each time a test is taken. Most sensor affixation requires the services of an attendant, especially if the sensor must be applied to the patient's back. However, even if it is possible to reach the desired sensor location, the patient would have to be specially trained to apply the sensor properly. Further, in cases where the electrode is strapped to a patient, the electrode will often not stay in the same position if the patient moves. To estimate blood flow through the heart there are basically two alternatives. In one alternative, a sensor intrusively enters the body through a vein and through the heart, thereby being a time-consuming, costly and dangerous testing procedure. The alternative method of ballistocardiography involves placing the subject on a special bed and involves using a motion transducer to measure body movement caused by the heart beat. Accurate use of a motion transducer requires that the body remain still and free from the effects of external movements such as microseisms in the ground, structural building vibrations, and dorsal tissue vibrations. However a motion transducer connected to a bed often yields data confused by spurious oscillating connections between the patient and the sensor. The prior art suggests that footboards, and lateral clamps or straps, greatly improve the coupling between the body and bed, and that the dorsal spring constant can be increased by having a rough surface on the bed so that when the subject lies on the bed with the subject's feet again a footboard and knees flexed, full extension of the legs keeps a high tension in the dorsal tissue all during data taking; however, even the better methods of ballistocardiography have not produced the reproducibility and accuracy desired. Moreover, the positioning of the patient with respect to the sensor, electrodes and ballistocardiograph bed, or the positioning of the sensors, electrodes, etc., with respect to the patient has required the services of an attendant skilled in the techniques required. Further, the excitations of body resonances by the familiar physician's "thumping" the chest has up to this time required the active attendance and participation of a highly trained professional.

US Referenced Citations (7)
Number Name Date Kind
3409007 Fuller Nov 1968
3830896 Flicker et al. Aug 1974
4272878 Danforth Jun 1981
4347213 Rogers, Jr. Aug 1982
4450843 Barney et al. May 1984
4583547 Granek et al. Apr 1986
4622185 Kostich Nov 1986
Foreign Referenced Citations (1)
Number Date Country
2711556 Sep 1978 DEX
Divisions (1)
Number Date Country
Parent 786746 Oct 1985
Continuations (1)
Number Date Country
Parent 73630 Jul 1987