Holder Apparatus for Transducer Applicable to Human Body

This invention relates generally to monitoring devices; and more particularly concerns the retention of unborn infant heartbeat monitoring transducers, as during labor.

In the past, such transducers were held in position on the enlarged abdomen of a woman in labor as via a strap or straps. The latter were necessarily extended all the way around the woman's back, and were uncomfortable, and difficult to keep in position during the many hours of labor leading up to childbirth. Clearly, there is need for improved means to hold such transducers in position on the abdomen.

It is a major object of the invention to provide a solution to the above difficulty and problem, to meet the described need.

Basically, the invention comprises monitoring transducer positioning apparatus that comprises

(a) an inverted generally cup-shaped holder to receive and position the transducer,

(b) first means associated with the holder to retain it to the patient's body, and

(c) second means on the holder to urge the transducer toward the patient's body, relative to the holder.

As will appear, the first means as referred to typically includes flange means projecting from the holder, and adapted to removably connect to retainer means that has an adhesive surface applicable to the patient's body. Such retainer means may take the form of a pad having a first portion connectible to the flange means and a second portion defining said adhesive surface. A second portion of the pad typically defines another adhesive surface adhered to the flange means.

It is another object of the invention to provide such flange means in the form of two flanges extending generally oppositely from skirt sections defined by said holder, the flanges being angled to fit the curvature of a pregnant patient's abdomen In this regard, the retainer means then may take the form of two pads, having first portions connectible to the respective flanges, and second portions defining adhesive surfaces applicable to a patient's body. Further, the two flanges and the pad first portions may advantageously have tongue and groove interconnection allowing the pads to be lifted off the flanges for temporary disconnection of the holder from the pads, while the pad second portions remain adhesively secured to the patient's body. Yet another object of the invention is to provide one or more adjustable set screws on the cup-shaped holder, to project into a recess defined by the holder, for urging the transducer toward the patient's body. Three such set screws may be provided, with ends engageable with the transducer at three locations.

The holder itself may include a base and skirt means integral with the base, there being threaded openings carried by the base for threaded reception of the adjustable set screws. The screws are typically carried by nuts on the base and pass through the nuts and the base for engagement with the transducer. The screws are typically spaced about a central through opening in the base, as will appear.

These and other objects and advantages of the invention, as well as the details of an illustrative embodiment, will be more fully understood from the following specification and drawings, in which:

FIG. 1 is a perspective view of apparatus incorporating the invention;

FIG. 2 is a plan view of the FIG. 1 apparatus, applied to the abdomen;

FIG. 3 is a side elevation of the FIG. 2 apparatus; and

FIG. 4 is a plan view of a retainer pad as used in FIG. 3.

In the drawings, positioning apparatus 10 is provided, for positioning a heartbeat monitoring transducer 11 adjacent the abdomen, such as the enlarged abdomen 12 of a Woman in labor. The transducer under surface 13 must be held firmly against the abdomen in order to properly detect heartbeat pulses of an unborn infant; and the transducer may also be used to detect uterine muscle activities. One such known transducer is manufactured by Hewlett Packard Company.

The apparatus 10 is in the form of an inverted, generally cup-shaped holder having a horizontally elongated base wall 14, two skirt sections 15 and 16 integral with the base wall and extending generally downwardly from the latter, and two flanges 17 and 18 respectively connected to the skirt sections and extending laterally and downwardly, at angles from horizontal to fit the abdomen curvature. These elements may consist of lightweight molded plastic material, so that they define a unitary bracket-type means. The skirts may be regarded as skirt means, and the flanges as flange means.

A central opening 20 in the base wall 14 is adapted to receive an enlargement 11a on the top of the transducer; but opening 20 is not required in the event the transducer does not incorporate such an enlargement. Elements 14-18 are typically quite thin, as for example between 1/14 and 1/8 inches in the plane of the base, as well as generally normal to the planes of the skirt sections.

The flanges 17 and 18 are adapted to removably connect to like pads 28 and 29 which in turn are adapted to be adhesively attached (removably) to the patient's body, as at 30 and 31 in FIG. 3. FIG. 4 shows the underside 28a of a pac 28, with a sheet 33 covering adhesive 34 on the pad. When the sheet 33 is pulled off, the pad is turned over and pressed onto the abdomen to removably attach adhesive 34 to the skin.

Another portion of each pad is connectible to a flange, to hold the flange against the abdomen. See for example portion 28b of pad 28 in FIG. 4, with openings or grooves 35 formed therein Such openings are adapted to receive or pass tongues or projections 36 on the flange 17. Those tongues are angled upwardly and toward the skirt section 15, i.e. away from the pad adhesive portion, to prevent inadvertent loosening of the tongue and groove connections when the pad retains the flange to the abdomen. Conversely, this form of connection allows ready lift-off detachment of the pad from the flange, without pulling the pad adhesive from the skin, whereby the cup-shaped holder and the transducer may be lifted from, i.e. removed from, the patient's abdomen should the patient desire to rise and walk about.

Pad 29 is attached to flange 18 in the same way as pad 28 connects to flange 17; and pad 29 is also adhesively attachable to the patient's abdomen. Such pads may be regarded as within the scope of first means adhesively attachable to the patient's abdomen. Such pads may be regarded as within the scope of first means associated with the holder to retain it to the patient's body.

Second means is also provided on the holder to adjustably urge the transducer toward the patient's body when the pads retain the holder in FIG. 3 position. Such second means typically may include at least one set screw projecting into a recess 40 formed by the holder beneath base wall 14 and between the like skirt sections 15 and 16. As for example, the three like set screws 45, have lower ends 45a engaging the top wall 11c of the transducer, thereby urging the transducer bottom wall 13 firmly against the abdomen.

The set screws have threaded shanks 45a engaging the nuts 47 integral with the base wall 14 and located above the latter. The screws project above the wall 14 and nuts 47, and have knob-like heads 45c that are individually adjustably rotatable to press different portions of the transducer downwardly relative to the base wall 14, for firm and best acoustic coupling to the abdomen, thereby to efficiently pass sound waves to the transducer. As referred to the device can be used to detect uterine muscle activities.

The set screws are spaced about the central opening 20 in the base wall 14, as shown, so as not to interfere with enlargement 11a. The nuts and set screws may also consist of lightweight, plastic material.