U.S. patent number 3,847,157 [Application Number 05/370,900] was granted by the patent office on 1974-11-12 for medico-surgical tube.
Invention is credited to James C. Caillouette, Paul E. Johnson.
United States Patent |
3,847,157 |
Caillouette , et
al. |
November 12, 1974 |
MEDICO-SURGICAL TUBE
Abstract
A tube structure is disclosed, for use within living tissue,
incorporating a magnetic element whereby the location and length of
the tube within tissue may be readily detected. In one disclosed
form, the tube is seamless, flexible and is formed of non-fibrous
imperforate material containing ferromagnetic material for magnetic
detection. In the forms as disclosed, the ferromagnetic material
comprises an integral metal strip, particulate or segments of
material extending along the length of the tube. A separate
grounding strip may also be included in a tube as disclosed, that
is radio-opaque for X-ray detection. The tube generally is tapered
to define a distal end. A magnetic detector for sensing the tube is
also disclosed utilizing a movably supported gapped magnetic
toroid.
Inventors: |
Caillouette; James C.
(Pasadena, CA), Johnson; Paul E. (San Marino, CA) |
Family
ID: |
23461643 |
Appl.
No.: |
05/370,900 |
Filed: |
June 18, 1973 |
Current U.S.
Class: |
600/433; 138/118;
600/435; 600/581 |
Current CPC
Class: |
A61B
5/062 (20130101); A61M 25/0127 (20130101); A61B
5/06 (20130101); A61B 34/73 (20160201); A61M
25/0108 (20130101); A61M 2205/0233 (20130101); A61M
16/0488 (20130101); A61M 2205/32 (20130101); A61M
16/0411 (20140204) |
Current International
Class: |
A61B
5/06 (20060101); A61M 25/00 (20060101); A61M
25/01 (20060101); A61M 16/04 (20060101); A61m
025/00 () |
Field of
Search: |
;128/348,349R,349B,349BV,35R,351,276,2M,2R,1.3,1.4-1.5,356,33R
;138/118 |
References Cited
[Referenced By]
U.S. Patent Documents
Other References
RCA Tech. Notes, June 1966, RCA TN No. 675, Morey.
|
Primary Examiner: Truluck; Dalton L.
Attorney, Agent or Firm: Nilsson, Robbins, Bissell, Dalgarn
& Berliner
Claims
What is claimed is:
1. An externally detectable tube structure for use within living
tissue, as to establish an access passage comprising:
a seamless elongated tube comprising an integral wall of flexible
non-fibrous imperforate material for insertion into living tissue;
and
a quantity of ferromagnetic material disposed within said wall
along a substantial length of said tube for magnetic detection at
an external location in relation to said living tissue, said
material being flexible in said tube, to accommodate flexibility of
said tube.
2. A tube structure according to claim 1 wherein said ferromagnetic
material is magnetized by domains of a dominant sense of magnetism
along the entire substantial length thereof and aligned with said
elongated tube.
3. A tube structure according to claim 1 wherein said ferromagnetic
material comprises a continuous strip that extends substantially
the full length of said tube.
4. A tube structure according to claim 3 wherein said ferromagnetic
material is magnetized by domains of a dominant sense of magnetism
and wherein said dominant sense of magnetism aligns to the elongate
tube.
5. A tube structure according to claim 1 wherein said ferromagnetic
material comprises separate spaced-apart segments of particulate
material defining a strip.
6. A tube structure according to claim 5 wherein said tube material
is transparent and said ferromagnetic material is confined to a
defined radial segment in the wall of said tube.
7. A tube structure according to claim 1 wherein said ferromagnetic
material comprises an integral wire extending along the elongated
dimension of said tube.
8. A tube structure according to claim 1 wherein said tube material
is transparent and further includes an electrically conductive
strip extending substantially the full length of said tube and from
the interior to the exterior of the wall of said tube.
9. A tube structure according to claim 1 wherein one end of said
tube is of reduced cross section to define a distal end.
Description
BACKGROUND AND SUMMARY OF THE INVENTION
The need frequently arises to place medico-surgical tubes, e.g.,
catheters, within various living-tissue spaces. In placing such
tubes, it is sometimes critically important that the attending
person have knowledge with respect to the precise location of the
tube. In that regard, it previously has been proposed to provide
tubes that are partially or completely X-ray opaque. In using such
tubes, the precise position of a tube is indicated by X-ray
presentations. However, a basic difficulty with such procedures and
techniques resides in the complexity of the required equipment and
a concern regarding repeated or prolonged X-ray irradiation of
living tissue.
Generally, there is a substantial current trend toward increased
activity by paramedical personnel in emergency situations. The
risks attendant such practice are related to the limitations of
paramedical personnel and the fact that they often must work in
locations where only simple and rudimentary equipment is available.
One piece of equipment commonly provided for use by paramedical
personnel is a medico-surgical tube. For example, such tubes are
often necessary to restore respiration for one reason or another.
These considerations emphasize the need for a simple tube, the
location and length of which within living tissue can be readily
determined, without irradiating the tissue or utilizing other
complex equipment.
Another consideration regarding medico-surgical tubes relates to
the electrical characteristics. There is concern both with regard
to electrical leakage currents from associated equipment that might
endanger a patient and static electricity that may produce a
sufficient spark to ignite combustible substances, e.g., gas. Fatal
arrhythmias can result from either form of electrical activity.
Accordingly, a need exists for a medico-surgical tube, the location
of which is readily detectable as indicated above, and additionally
which has certain electrical characteristics. Other desirable
characteristics for a medico-surgical tube include flexibility and
transparency to permit observing the tube interior.
In general, the present invention relates to a medico-surgical tube
system whereby the location of a tube within living tissue may be
simply, accurately and easily determined. Specifically, the system
includes a tube of flexible, transparent imperforate material
carrying a strip of continuous or discretely placed segments of
magnetic material for actuating a magnetic indicator. In the
disclosed embodiments, a strip of magnetic material is provided to
extend along the length of the tube and comprises magnetizable
material having a remanent magnetic flux density that is relatively
high and which is magnetized with a pattern so as to be readily
detected outside the living tissue. The magnetizable material may
be provided in a form to accomplish desirable electrical
characteristics or a separate conductive strip may be provided. The
location of the tube is manifest by a movably mounted permanent
magnet housed for convenient placement contiguous to the living
tissue.
BRIEF DESCRIPTION OF THE DRAWING
In the drawing, which constitutes a part of this specification, an
exemplary embodiment demonstrating various objectives and features
hereof is set forth as follows:
FIG. 1 is a diagrammatic view illustrative of the use of a system
constructed in accordance with the present invention;
FIG. 2 is a plan view of one form of tube structure in accordance
with the present invention;
FIG. 3 is an enlarged sectional view taken along line 3--3 of FIG.
2;
FIG. 4 is a view similar to FIG. 3 illustrating an alternative tube
construction;
FIG. 5 is a view similar to FIG. 3 illustrating still another
alternative tube construction;
FIG. 6 is a fragmentary view similar to FIG. 2 illustrating still a
further alternative tube construction;
FIG. 7 is a plan view of an indicator constructed in accordance
with the present invention; and
FIG. 8 is a central vertical sectional view taken through the
indicator of FIG. 7.
DESCRIPTION OF THE ILLUSTRATIVE EMBODIMENT
As required, a detailed illustrative embodiment, deemed to be the
best form of the invention for that purpose, is disclosed herein.
The embodiment exemplifies the invention which may be constructed
in various other forms, some of which may be quite different from
the disclosed illustrative embodiment. However, specific structural
and functional details disclosed herein are representative and in
that regard provide a basis for the claims herein which define the
scope of the invention.
Referring initially to FIG. 1, a human subject S is suggested along
with indications of lungs L and air passages including a right
bronchial tube 12, a left bronchial tube 14 and a trachea 16. Also,
as indicated in FIG. 1, a medico-surgical tube T is shown passing
through the trachea 16 and the right bronchial tube 12 to enter the
right lung L. The position of the tube T is indicated by an
indicator I which is as illustrated in FIG. 1, located on the chest
of the subject S.
In considering an exemplary use of the present system, the tube T
is placed within the subject S for the extraction of fluid from the
lung cavity. It is to be recognized that the tube hereof is also
useful in other ways, e.g., vascular, gastrointestinal,
genitourinary, and so on. It is apparent that the tube T may
substantially close the receiving bronchial tube, e.g., bronchial
tube 12. Frequently, a subject S has lost the use of one lung as a
result of the accumulation of fluid. Consequently, if the tube T
(being placed for the purpose of removing the fluid) enters the
bronchial tube of the single functioning lung, the subject S may
lose all breathing capacity.
In accordance with the system of the present invention, the
position of the tube T is manifest by the indicator I during the
period of insertion. If the tube deviates in an undesired
direction, the fact is promptly manifest by the indicator I,
permitting corrective action to be taken. Detailed consideration
will now be given to the structure of the tube T as well as the
indicator I, pursuant to presenting the basis for a complete
understanding of the system.
The tube T is a seamless, imperforate, elongated medico-surgical
tube having a substantially uniform cross section except for a
reducing taper at the distal end 20 and a slight enlargement or
flare at the opposed end 22. The taper at the distal end 20 is
helpful in probing and additionally is cooperative in
interconnecting a series of tubes.
The tube is smooth at both the internal wall 24 (FIG. 3) and the
external wall 26. Continuing to view the tube in cross section
(FIG. 3) a radial segment comprises a strip 28 (FIG. 2) extending
the full length of the elongated tube T and fully occupying a space
between the internal wall 24 and the external wall 26. The
non-strip portion 30 of the tube may be formed of clear or
transparent plastic to afford a view of the tube contents or may be
radio opaque for X-ray detection. The strip 28 may comprise similar
plastic containing a concentration of ferromagnetic particles. For
example, fine particles of magnetic material comprising
approximately 80 percent nickel and 20 percent iron may be employed
to provide a strip with retentive magnetic characteristics.
Generally, if the strip 28 is to render the tube T conductive, the
concentration of the particles should be relatively high.
In reducing the tube T, extrusion techniques may be employed as to
form vinyl plastic material. Such techniques are well known in the
plastics industry and are not deemed significant for disclosure
herein. After formation of the tube, the strip 28 is magnetized
along the entire length of the tube T to attain a dominant magnetic
pattern that has a uniform sense. For example, the magnetic pattern
may be with the distal end 20 as the north pole of the magnet while
the opposed end 22 is magnetized as the south pole. Of course,
various magnetizing techniques may be employed to accomplish such a
pattern, as for example, placing the ends of the tube T in
alignment contiguous to the ends of a powerful electromagnet so
that the strip 28 is an element in a single magnetic circuit and is
subjected to considerable magnetic flux.
In using the tube T after magnetization, it is significant that the
magnetic field provided by the strip 28 as well as the inherent
magnetic material in the strip provide the basis for sensing the
location of the tube T. The sensor or indicator I as disclosed
herein includes a housing 40 (FIG. 6) that is pointed along one
plane, however, otherwise is of parallelepiped configuration. The
upper surface 42 of the housing 40 provides an instrument display
for indicating alignment with or position of the strip 28 in the
tube T. As described, the housing 40 is tapered to a point 44 at
the forward end. The upper surface 42 defines a window 46 through
which a magnet 48 is exhibited. The magnet 48 carries a meter mark
50. Displacement of the meter mark 50 from alignment with an index
mark 52 indicates a position of the tube T in the proximity of
indicator I.
The magnet 48 in the indicator I is in a toroid form (defining a
non-magnetic gap 54) and is concentrically supported by a coil
spring 56 the center of which is affixed to a lateral post 58 that
is anchored in the housing 40. When the indicator I is independent
of substantial magnetic fields (or magnetic medium) the gap 54 is
held in a quiescent position substantially as indicated in FIG. 7,
resulting in the meter mark 50 (FIG. 6) being aligned with the
index mark 52.
In using the indicator I, the bottom surface 60 is usually
separated from the strip 28 by a section of living tissue 61.
However, upon the flux field of the strip 28 encountering the flux
field of the magnet 48, the latter is displaced counterclockwise
(as indicated by the arrow 63) toward a position in which the strip
28 would close the non-magnetic gap 54. With such displacement, the
meter mark 50 (FIG. 6) is moved forward from the index mark 52
indicating that the strip 28 (and accordingly the tube T) has been
sensed. It may, therefore, be seen that the indicator I may be
variously moved over the subject S (FIG. 1) to follow or indicate
the position of a tube T.
As suggested above, the T may take various forms other than with
the strip 28 of magnetic substance. In one alternative construction
(FIG. 4) the tube may be a clear, somewhat cylindrical elongated
body 65 into which a thin wire 66 of magnetic material is embedded.
Additionally, a segmental strip 68 of conductive material, e.g.,
carbon, extends the full length of the tube T. In such a structure,
the transparent body 65 affords a view of the interior of the tube.
The wire 66 is magnetized as described, along a single polarity
orientation for effective sensing. Thus, the desired electrical
characteristic for the tube is provided by the strip 68 which
extends completely through the tube and along its entire
length.
With regard to small tubes, it may be desirable to provide a
somewhat-uniform extrusion of plastic containing a dispersion of
magnetic material. A form of such a tube is depicted in FIG. 5 and
essentially consists of a homogeneous mixture of particle magnetic
material in a carrier, as for example, of plastic.
As still another alternative, the tube may be as illustrated in
FIG. 2; however, altered by the magnetic strip being in the form of
slugs or segments 71 (FIG. 6). Specifically, the segments 71 are
spaced apart by a predetermined distance D so as to provide another
source of information in the use of a magnetic detector. Of course,
the length of the segments 71 is also predetermined.
Of course, other forms of tubes may be employed in accordance with
the teachings hereof to accomplish an effective structure for use
within living tissue and which may be simply and easily located to
define both position and path. Consequently, the scope hereof shall
not be determined with limitations relating to the embodiment set
forth herein, rather, however, shall be defined by the claims as
set forth below.
* * * * *