U.S. patent number 3,911,930 [Application Number 05/447,164] was granted by the patent office on 1975-10-14 for method and structure of preventing and treating ileus, and reducing acute pain by electrical pulse stimulation.
This patent grant is currently assigned to Stimulation Technology, Inc.. Invention is credited to Norman R. Hagfors, Alan C. Hymes.
United States Patent |
3,911,930 |
Hagfors , et al. |
October 14, 1975 |
Method and structure of preventing and treating ileus, and reducing
acute pain by electrical pulse stimulation
Abstract
The disclosure is directed to the method and structure of
artifically inducing the return of arrested body functions caused
by paralytic ileus and pain associated therewith after surgery or
accidental trauma on the human body. The equipment is in the form
of electronic circuits producing a generally rectangular or square
wave shape which is variable from 10 to 300 pulses per second
having a pulse width of 50 to 1,000 microseconds. The circuit
includes a pair of constant current amplifiers capable of supplying
two different output signals having a pulse amplitude of 80
milliamperes maximum current to provide a current density range of
1 to 50 .times. 10.sup..sup.-6 amperes per square millimeter
depending on the electrode area or size. Electrodes are connected
to current generators and placed on the body in the area of the
lower abdomen in accidental trauma or close to the area of incision
post operatively. Posterior electrodes may also be placed on the
body as well as over the nerves and particularly the intercostal
nerves leading to the site of the incision to further aid in
restoring body functions. Electrodes are also connected to current
generators and placed on the body at various locations where a
traumatic condition and/or surgery produce a number of localized
areas of pain. The application of the electrical pulses stimulates
the body and restores its body functions and alleviates the normal
problem associated with surgery in the chest cavity, the abdominal
cavity and also generally reduces the pain associated therwith. The
use of electrodes may also be connected to current generators and
placed adjacent to, or within a localized area in the treatment or
prevention of paralytic ileus without regard to what brought it
on.
Inventors: |
Hagfors; Norman R.
(Minneapolis, MN), Hymes; Alan C. (Minnetonka, MN) |
Assignee: |
Stimulation Technology, Inc.
(Minneapolis, MN)
|
Family
ID: |
23775255 |
Appl.
No.: |
05/447,164 |
Filed: |
March 1, 1974 |
Current U.S.
Class: |
607/46; 607/64;
607/66; 607/74 |
Current CPC
Class: |
A61N
1/36007 (20130101); A61N 1/36021 (20130101) |
Current International
Class: |
A61N
1/36 (20060101); A61N 001/36 () |
Field of
Search: |
;128/404,416-418,419R,421,422 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
Primary Examiner: Kamm; William E.
Attorney, Agent or Firm: Simkanich; John J.
Claims
What is claimed is:
1. The method of treating pain in the human body as a result of
experiencing a traumatic condition such as surgery or accidental
trauma including the steps of:
a. generating a series of electrical rectangular, single frequency,
fixed duration pulses within the range of 50-1000 microseconds
duration and the repetition frequency range of approximately 10-300
pulses per second and of substantially constant amplitude;
b. securing at least a pair of rectangular body electrodes in
juxtaposition on the skin surface and parallel to the localized
area of traumatic pain in the body;
c. and applying said series of electrical pulses to said body via
said electrodes with a current density of 1-50 microamperes per
square millimeter continuously for a period of 20-30 minutes every
2-4 hours until the pain caused by said traumatic condition is
observed to be substantially overcome.
2. The method as set forth in claim 1 wherein the step of securing
at least a pair of body electrodes includes providing each
electrode-body interface for electrical current flow of 3-30 square
inches.
3. The method as set forth in claim 2 including the steps of:
securing at least a second pair of body electrodes posteriorly to
the localized area of pain in the body whereby said electrodes
cover the nerves leading to the site of the pain; and
applying said series of electrical pulses to said posteriorly
positioned pair of body electrodes similarly as with said locally
positioned pair of electrodes.
4. The method as set forth in claim 3 wherein the step of
generating a series of electrical pulses includes generating said
pulses with a peak current amplitude of 10-80 milliamperes.
5. The method of treating pain in the human body as a result of
experiencing a traumatic condition such as surgery or accidental
trauma including the steps of:
a. generating a series of electrical rectangular pulses of 200-400
microseconds duration having a repetition frequency of
approximately 100-160 pulses per second and of substantially
constant amplitude;
b. securing at least a pair of rectangular body electrodes
posteriorly to the localized area of traumatic pain in the body
whereby said electrodes cover the nerves leading to the site of the
pain;
c. and applying said series of electrical pulses to said body via
said electrodes with a current density of 1-50 microamperes per
square millimeter continuously until the pain caused by said
traumatic condition is observed to be substantially overcome.
6. The method as set forth in claim 5 wherein the step of
generating a series of electrical pulses includes generating said
pulses with a peak current amplitude of 10-80 milliamperes.
7. The method of treating or preventing paralytic ileus in the
human body brought on after surgery, accidental trauma or
pathological conditions including the steps of:
a. generating a series of rectangular electrical pulses of 50-1,000
microseconds duration having a repetition frequency of
approximately 10-300 pulses per second and of substantially
constant amplitude;
b. securing at least a pair of elongated body electrodes on the
skin surface of the body in juxtaposition to at least one of a
surgical incision made in the body, a localized area of accidental
trauma, or a localized area formed by a pathological condition;
c. and applying said series of electrical pulses to said body via
said electrodes with a current density of 1-50 microamperes per
square millimeter continuously until the paralytic ileus is
observed to be substantially overcome, or prevented.
8. The method as set forth in claim 7 including the steps of:
securing a pair of body electrodes posteriorly to cover the nerves
leading to any surgical incision made in the body, any localized
area of accidental trauma, or any localized area formed by a
pathological condition; and
applying said same series of electrical pulses at said same current
density to said posteriorly positioned electrodes as to said
juxtapositioned electrodes.
9. The method as set forth in claim 8 where the step of securing at
least a pair of elongated body electrodes includes providing each
electrode with a contact surface of 3-30 square inches.
10. The method as set forth in claim 9 wherein the step of
generating a series of electrical pulses includes generating said
pulses with a peak current amplitude of 10 to 80 milliamperes.
11. Apparatus for treating pain and for treating and preventing
paralytic ileus in the human body resulting from a traumatic
condition, such as surgery or accidental trauma, said apparatus
comprising:
a. a pulse generator generating a substantially rectangular wave
signal having a repetition rate of 10-300 pulses per second and a
pulse width variable from 50 to 1000 microseconds duration;
b. a pair of current generating means being excited by said pulse
generator and each having an output circuit independent of a load
to be connected thereto, said means each being individually
adjustable to supply a pulse amplitude of 10 to 80
milliamperes;
c. a plurality of flexible elongated electrodes being positionable
to the skin surface of the human body substantially within the
localized area of pain, said electrodes each having a current
conduction area of 3-30 square inches;
d. and a plurality of electrical conductors connecting said
plurality of electrodes to said pair of current generating
means.
12. The structure as set forth in claim 11 including:
e. an electrical current conducting gel applied to said body
electrodes and contacting the human body, being in cooperation with
said electrode in the conduction of current wherein the current
density is 1-50 microamperes per square millimeter.
Description
This application relates to a method and structure for electrical
stimulation of the body to restore arrested body functions and more
specifically to treating or preventing paralytic ileus and the pain
associated with accidental trauma and surgery.
It is well known that when abdominal surgery is performed, a
condition will generally be found characterized by inadequate
peristaltic activity (a forward motion of the bowel) affecting the
gastro intestinal system completely or locally which may result in
paralytic ileus. Prolonged loss of the peristaltic activity of the
gastro intestinal track generally leads to distension of bowel
loops with fluid and gas. If prolonged, a vicious cycle may occur
and the more distension that occurs, the more paralyzed the bowel
becomes. Paralytic ileus may also result from conditions other than
surgery such as accidental trauma or from a pathological
condition.
The management of this condition has been treated by numerous
means, directed at relieving distension by means of tube suction in
the stomach and intestine. An internal electrical means attached to
a suction tube to correct this situation is found in U.S. Pat. No.
3,411,507 but is also generally known that the results achieved by
the method set forth therein has also been somewhat inconsistent
and incomplete.
It has also been well established that complications of the lung
tissue may result from chest operations or accidental trauma and
this may take the form of a partial internal collapse of the lung
(called atelectasis). A significant reduction of post operative or
traumatic pain allows deep respiration and coughing, thus
preventing and treating atelectasis.
During the initial phases of the development of the treatment and
method of placement of the electrodes in carrying out our invention
and discovery, the patients were treated intermittently once or
twice a day for a period of 20 to 30 minutes. It has also been
established that for treatment of pain the best placement of the
electrodes on the patient is close to the surgical wound or site of
trauma. Generally, the best results have been achieved by keeping
the electrodes substantially parallel to the incision and on some
occasions by placing a second pair of electrodes on the body
covering the nerves leading to the site of the incision. Where the
area of pain is produced by some means other than surgery,
generally the electrodes are secured to the body within the
localized area of pain. However, good results have also been
achieved through the use of posterior electrodes alone and of
course where there are multiple areas of trauma such as may result
from an accident it may be necessary to use a number of electrodes
placed near the traumatic areas and require more than one generator
to energize the same.
The electrodes are formed of aluminum foil or other flexible
electrically conductive material. They are generally secured to a
piece of clear vinyl material or other flexible insulative backing
material which will conform to the contour of the body. It has been
found that the electrodes having a surface area greater than 3
square inches, depending upon the size of the surgical incision or
localized area of pain and up to 30 square inches generally give
the maximum flux density penetration of the body that is required
to correct the body function and pain associated therewith. The
current density has been found to have a range of approximately 1
to 50 microamperes per square millimeter, and is related to the
electrode area or size and the location of the same with respect to
the area to be treated.
It was also determined that the use of electrode gel has been
superior to the use of wet sponges for connecting the stimulator to
the body although generally there were no problems encountered in
choice of gel or wet sponge.
In evaluating the method and equipment, various observations were
made by comparison to a control group and a group using the
structure and practicing the method disclosed herein, and
specifically observations were made of: 1. The incidence of post
operative complications of ileus and atelectasis. 2. The time spent
in the intensive care unit. 3. In thoracotomy patients, the angle
their humerus could be raised before and after treatment. 4. The
ability of each patient treated to cough.
By way of example, of 250 operations in which the abdominal cavity
was opened, where electrical stimulation was used, there were no
cases of ileus detected. On the other hand, the expected rate of
ileus for the same operation without treatment is generally found
to be approximately 13 percent. By way of further example, of 22
patients with protracted ileus secondary to surgery and trauma,
treatment with surface electrodes and stimulation as described
herein, all patients subsequently developed active bowel tones and
within 48 hours the majority had bowel movements signifying a cure.
In addition, there was also a significant reduction in the time
spent in the intensive care unit for those patients being treated
with the electrical stimulation. On an average the length of stay
in the intensive care unit was reduce by approximately 1 day.
Thoracotomy patients treated with the electrical stimulation pulses
and as contrasted to a similar group of patients who were not
treated, showed that five patients of the treated group developed
clinical atelectasis confirmed by X-ray for a rate of 13 percent
compared to 15 patients of a control group of 30 who had post
operative atelectasis in the untreated group for a rate of 50
percent. The treated group had an average stay in the intensive
care unit of 3 days compared to 4.2 days for the control group. As
a measurement of patient activity following thoractic surgery,
patients could raise their arm so that the mean angle of the
humerus to the thoractic cage prior to treatment was 91.degree..
Following a few minutes of treatment, the average angle of the
humerus to the thoractic cage was noted to be 154.degree., or an
increase of 63.degree..
By way of further example, where 10 patients were treated as
disclosed herein after suffering fractured ribs, only one developed
atelectasis, for a rate of 10 percent. Another patient suffering
from atelectasis fully recovered after stimulation was applied. Out
of 12 patients suffering fractured ribs who were not treated with
stimulation as set forth herein, eight developed atelectasis, or in
other words, 66 percent developed atelectasis as compared to the 10
percent just described.
Subjective evaluation of these patients, however, revealed a pain
reduction of about 80 percent, and as a result, coughing improved
as noted by independent observers before and after treatment. The
presently described treatment is unlike acupuncture which controls
pains by needle stimulation at a distal site.
It became apparent that hyper activity of the gastro intestinal
track was reduced by the electrical stimulation and that the
majority of the patients treated with this electrical stimulus
expelled flatus with a short time thereafter and had a bowel
movement soon thereafter. Clinically, the bowel tones became hyper
active whereas preceding the stimulation they were hypo active to
absent.
It is therefore a general object of this invention to provide a
method and structure to induce the return of impaired body
functions causing atelectasis and paralytic ileus due to surgery,
accidental trauma or pathologic processes.
It is another object of the present invention to provide a method
and structure for treating pain in the human body as a result of
experiencing a traumatic condition such as surgery or accidental
trauma.
It is still a further object of this invention to provide a method
and structure for treating pain associated with accidental trauma
such as fractured ribs, a fractured clavical, a fractured coccyx,
subperiosteal hematomas and all soft tissue injuries and fractured
of bones.
It is still another object of the present invention to provide
signal generating means for generating signals of predetermined
pulse frequency and pulse width for controlling post operative
problems of atelectasis and paralytic ileus.
These and other objects and advantages of the invention will more
fully appear from the following description, made in connection
with the accompanying drawings, wherein like reference characters
refer to the same or similar parts throughout the several views,
and in which:
FIG. 1 is a diagrammatic view of a patient showing placement of
electrodes after abdominal cavity surgery;
FIG. 2 is a diagrammatic view of a patient showing placement of
electrodes after chest cavity surgery;
FIG. 3 is a diagram of a typical current pulse wave shape applied
to the electrodes; and
FIG. 4 is a schematic diagram of the electrical equipment and
electrodes which are attached to the body of the patient.
FIG. 1 discloses a pair of electrodes 10 and 11 which are placed
adjacent and parallel to the abdominal incision 12. A pair of
conductors 13 and 14 are connected respectively to electrodes 10
and 11 and are also connected to a pair of jacks 17 and 18 at the
front of a housing 19 which houses an electrical circuit 20 that
will be described in more detail subsequently, and is shown in FIG.
4. Another pair of jacks 21 and 22 are used to energize another
pair of electrodes 23 and 24 (FIG. 4) through another pair of
electrical conductors 25 and 26 respectively.
FIG. 2 discloses a patient having an incision in the chest cavity
and electrodes 10 and 11 are shown placed substantially parallel to
and running the length of the incision. It was found that during
the various applications of the electrodes and use of the equipment
that the optimum results were obtained by using a pulse width of
approximately 200 to 400 microseconds with a frequency of 100 to
160 pulses per second.
FIG. 4 shows the electrical circuit 20, which generates the
electrical signals. Transistors Q1 and Q2 are connected in the form
of a free running multivibrator producing a rectangular or square
pulse wave, the frequency of which is controlled through a setting
of variable resistor R3 and capacitor C3 to adjust the frequency or
repetition rate. The repetition rate is adjustable from
approximately 10 to 300 pulses per second.
A pulse width circuit is formed from transistors Q3, Q4 and Q5
which are connected to the multivibrator or oscillator through a
capacitor C2. The pulse width is determined by a time constant
developed through an RC network of capacitor C4 and variable
resistor R11, and is adjustable from 50 to 1,000 microseconds. A
pulse signal is obtained from the junction of the collectors of
transistors Q3 and Q4. The signal is applied to the bases of
transistors Q6 and Q9 through resistors R13 and R14. The signals
are amplified and appear across variable resistors R15 and R16
connected respectively to the collectors of transistors Q6 and Q9.
The first output stage further amplifies the signal through
transistors Q7 and Q8 to provide a constant current output which is
independent of the load through transformer T1. Diode D2 is used to
reduce the inductive voltage due to the collapse of the field at
transformer T1.
The second output circuit also includes a pair of transistors Q10
and Q11 which further amplify the signal received from Q9 and apply
the same to an output transformer T2 which also provides a constant
current output signal independent of the load connected thereto.
Diode D3 acts in a manner similar to that of diode D2 in
controlling the induced current flow through transformer T2.
Variable resistors R15 and R16 provide a means of varying the
amplitude at the two output stages which may have a peak current
amplitude, adjustable from 10 to 80 milliamperes. Expressed in a
different manner, the electrical pulses generated should produce a
peak current density range of approximately 1 to 50 microamperes
per square millimeter of electrode area depending on the electrode
size and its placement on the body with respect to the area to be
treated or controlled. While the wave shape shown in FIG. 3 has
proven to be an optimum shape, it should also be understood that
other peaked wave forms may be used such as triangular or saw tooth
waves and those having some slope to their leading or trailing
edges.
A diode D1 is connected in series with the supply battery B1 and
the connection to transistors Q1, Q2, Q3, Q4, and Q5 forming the
pulse generator to decouple the generator and output stages. Upon
closing switch S1, power is applied to the pulse generator and
pulse width circuits as well as the current amplifiers, to supply
an output voltage of the characteristics disclosed in FIG. 3.
Through the use of the teaching as disclosed herein, it will be
apparent that post operative pain, traumatic pain and other post
operative complications may be alleviated so that the patient may
resume deep breathing and coughing thus reducing pulmonary
complications for surgery performed in the chest and abdominal
cavities. Through the use of electrical stimulation as disclosed
herein, paralysis of the bowel is alleviated, thus preventing post
operative ileus, a condition of paralysis of the bowel leading to
distension with fluid and gas which may lead to complication of
bowel obstruction. As a result of the beneficial treatment
described herein, there is a marked reduction of pulmonary
complication and bowel paralysis resulting in a reduced hospital
stay by the patient in an intensive care unit. Electrical
stimulation, upon being applied to the localized area of pain and
particularly adjacent each side of an incision, or area of pain, is
generally given to the patient on a continuous basis for two or
three days, or stimulation may be used intermittently from 20 to 30
minutes every 2-4 hours.
It has been found that reduction of pain permits the return of
certain body functions such as deep breathing and coughing which
may have been reduced due to accidental chest trauma resulting from
fractured ribs and/or pulmonary contusions, i.e., hemorrhaging
within the lungs. Similar results may be achieved in preventing
ileus following trauma from a fractured pelvis and/or hematoma in
the retio peritoneal space, i.e., the area posterior to the
abdominal cavity. In other words, stimulations by the electrical
signals through the method and equipment disclosed herein has
proven to be extremely helpful in the control of post traumatic
pain due to fractured ribs, a fractured clavical, and subperiosteal
hematoma of the leg and other sites of fractures of bones or soft
tissue contusions.
It has also been found that the use of posterior electrodes may
function well by themselves without regard to their use with
electrodes in a localized area. Where multiple applications are
needed it may be necessary to use two units such as disclosed
herein, particularly where multiple areas of application are
required.
Through the teachings disclosed herein, treatment or control of
pain in the chest cavity or abdominal cavity caused traumatically,
that is by accident, or by surgery, has proven to be highly
successful.
It will, of course, be understood that various changes may be made
in the form, details, arrangement and proportions of the parts
without departing from the scope of the invention which consists of
the matter shown and described herein and set forth in the appended
claims.
* * * * *