Special Considerations of Local Iodine Therapy.
When we undertake the consideration of those features of iodine therapy
which have to do with its adaptability to definite remedial ends, we
enter upon a field of thought that may take several forms.
We are concerned, in this treatise, only with matter relating to
regional, topical, or local applications of the agent under discussion,
and we can well begin the consideration with the identification of the
agent itself and the different forms under which it is most commonly
used. For all practical purposes, we can confine the discussion of the
agent itself to that of the four forms, or preparations, of iodine
in almost universal use by practitioners of veterinary medicine and
surgery. When, in veterinary medicine, allusion is made to iodine, it
is almost, without exception, to one of the following preparations:
1. Tincture of Iodine.
2. Ointment of Iodine.
3. Aqueous solutions of Iodine.
4. Oily solutions or mixtures of Iodine.
Only in rare cases, and then under specific reference, is iodine used
in other forms, or in its elemental state, in veterinary medicine.
Iodine is a very active agent, chemically as well as therapeutically,
and is not readily compatible with other agents. It is for this reason,
that combinations of iodine with other drugs and chemicals are not
common, and therein lies a distinction for iodine that not many other
therapeutic agents can claim; namely, that beneficial effects resulting
from iodine medication are almost, without question, due to it alone;
it is hardly ever applied in combination with synergists which might
obscure the activity of individual ingredients.
This remarkable therapeutic activity of iodine is such that, when
properly applied in some of its forms, its presence can be demonstrated
in the underlying tissues. After prolonged courses of topical
application, its action is occasionally appreciated, both subjectively
and objectively, in the evidence of more or less clearly defined
constitutional or systemic indications of its presence within the
animal organism.
From this, it is apparent that, in iodine preparations of a particular
class, we have an agent whose topical remedial effects are, in some
slight measure, due to systemic action; in part at least, this action
being the effect of great physiological activity exerted in the limited
area of its topical application. In some degree this activity of
certain preparations of iodine can be explained by reference to the
chemical properties inherent in iodine as elemental matter, and in its
well-known affinity for certain elemental constituents of the tissues
of the animal organism.
The foregoing throws some light on the therapeutic accomplishments
of iodine preparations, when topically applied, and, to a certain
extent, explains its _modus operandi_ in a physiological sense--an
understanding somewhat essential from an ethical standpoint. The old
theory, which would ascribe to an increase in function of the regional
lymphatic glands all the agreeable therapeutic effects of local iodine
applications, does not cover enough ground; it is only when we amplify
this theory, with the assumption of the considerations aired in the
foregoing paragraphs, that we find it possible to attain a clear
understanding of the physiological action of iodine preparations
applied regionally.
_The Clinical Aims_ for topical therapy are to be classified as follows:
1. PROPHYLACTIC.
2. AMELIORATIVE.
3. CURATIVE.
Under these three heads, we further sub-classify the actual clinical
conditions, which are indicated, into the following:
Under 1. Surgical preparatory technique.
Under 2. Acute pathological conditions, in the corrections of which
topical applications of iodine preparations are used as an adjunct to
internal medication with other agents.
Under 3. Chronic pathological conditions, in which one or more of
various iodine preparations, locally applied, constitutes the entire
treatment.
This classification and sub-classification is important and essential
when we endeavor to make our use of iodine conform to ethical
standards; it is also very essential to the attainment of certain
therapeutic ends in actual practice.
1. THE LOCAL APPLICATION OF PREPARATIONS OF IODINE IN THE SENSE OF
PROPHYLACTIC AIM IN SURGERY.
The exhaustive pre-operative washing and scrubbing of the integument,
that veterinary practitioners applied to their surgical patients in
years past, has given way almost entirely to iodine painting. Even
those surgeons who still adhere to the scrubbing and washing of the
parts about to be incised, complete the process with an application of
iodine thereafter.
An application of iodine to the skin covering the region that is
about to be invaded by the knife of the surgeon, has been found much
more efficacious and much more reliable than has the washing and the
scrubbing with antiseptic solutions, soaps and other agents. Not only
this, but it has also greatly simplified and shortened an otherwise
tedious, prolonged and sloppy technique. Whereas, the surgeon formerly
spent from fifteen minutes to half an hour scrubbing and washing the
field of operation, he now applies a few coats of iodine tincture--a
few strokes of the swab or brush--and it is done.
This simplified technique has the added advantage of the total
elimination of basins, brushes, and sponges for use in the preliminary
stages of an operation, as well as the agreeable absence of the
wet, sloppy field that inevitably resulted from the use of the older
method in veterinary practice. Besides, it spares the patient in more
ways than one, especially in the cold months of the year when, in a
veterinary practice, operations frequently have to be performed in cold
stables, or even in the open.
While the application of tincture of iodine gives ample protection from
skin infection in surgical operations, there are a few things to be
observed that have to do with making the application correctly. First,
in veterinary patients, the hair must be clipped off and the area
shaved clean. The area clipped and shaved should be slightly greater
in extent than the field actually to be invaded by the knife. When
the clipping and shaving have been done, the area should be lightly
brushed with a stiff, dry brush, in order to remove dandruff and scurf.
The second--and the most important--point is that the surface that is
to be painted with the tincture of iodine be perfectly dry. In the
event that the area to be painted should contain a deposit of filth,
oily or greasy in nature, this should first be removed by swabbing and
wiping with gauze or cotton saturated with gasoline, benzine or ether;
these remove oily, greasy or fatty filth and evaporate quickly, leaving
the area perfectly dry and clean. Washing with watery solutions,
previous to the iodine application, is not recommended under any
conditions.
When the area has been clipped, shaved, freed from grease or other
filth, and then allowed to become perfectly dry, the tincture of iodine
is applied liberally with a soft brush, or with a cotton swab. This is
allowed to dry for a minute or two; another application is then made
directly on top of the first one, allowed to evaporate to dryness, and
the field is ready for the incision.
As iodine readily attacks metals, and spoils the plating on
instruments, no instrument should be allowed to come in contact with
the painted area while it is still moist; neither should the iodine
be used for disinfecting purposes on any utensils or apparatus made
of metal. The fact that the iodine may injure instruments can not be
considered in the light of a disadvantage, if the above precautions are
taken.
Another practice that has come to be recognized quite generally among
surgeons is that of painting the edges of the surgical wound with pure
tincture of iodine just before the wound is to be closed with sutures.
Whether this is good practice, on general principles, is a matter that
is open to debate. If the painting is done carefully, so that a pool of
iodine tincture is not formed by the surplus gathering by gravitation
into the deeper recesses of the wound, this may be considered good
practice. On the whole, however, it would appear that the iodine could
act, in many instances, as an undesirable irritant when it comes in
contact with delicate, freshly incised tissues.
As the object, in modern surgery, is to eliminate all things, even the
slightest, that may hinder prompt repair and smooth healing of the
invaded tissues, the presence of such an active agent as pure tincture
of iodine in a surgical wound may be looked upon as interfering with
the carrying out of that object.
On the other hand, in surgical wounds of an already infected character
in which primary union would be out of the question, the application
of pure tincture of iodine, in liberal amounts, can not be too highly
endorsed.
The latter statement applies, with even greater force, to all wounds of
an accidental character in the fleshy portions of the anatomy.
It is also the practice of many veterinary surgeons to apply pure
tincture of iodine to the wound after the sutures have been put into
place. This is a very satisfactory practice, if the painting is done
gently and not too freely. An excess of the tincture of iodine--if
the wound edges have not been coapted perfectly--may result in cause
for stitch abscess when a considerable amount of the iodine becomes
pocketed in some part of the wound under the line of suture.
In certain animals, whose skins are very tender, the local application
of pure tincture of iodine, previous to surgical incision, is followed,
in a few days, by slight peeling of the integument. This is so rare an
occurrence, however, and of so little consequence, that it need not be
considered, and can not be looked upon as a drawback to this otherwise
salutary practice.
Aside from its use in the preparation of the surgical field, tincture
of iodine is also used, in a prophylactic sense, to prepare the
skin--in a similar manner--for the entrance of the hypodermic needle
whenever a subcutaneous injection is to be made. It is not practical,
nor necessary, in this instance, to shave away the hair; the site that
has been selected for the needle puncture is merely painted liberally
with the iodine. As in the case of a surgical incision area, so also
here, the parts to which the application is made must be perfectly dry.
2. THE USE OF IODINE AS AN ADJUNCT TO INTERNAL MEDICATION IN THE
CORRECTION OF ACUTE PATHOLOGICAL CONDITIONS.
Iodine preparations of various forms are very commonly used topically
as an adjunctive treatment to internal medication in the treatment of
a number of acute pathological conditions in veterinary patients. The
object in adding local iodine applications to the handling of such
conditions is varied. In some cases, the object of the practitioner is
to hasten the correction of certain well-marked local manifestations of
the disease with which the patient is afflicted. In other instances,
the aim of the practitioner is toward the prevention of these local
manifestations. Occasionally, in a certain type of pathological
conditions, the practitioner intends, by the use of topical iodine
applications, to enhance the internal treatment being aimed at symptoms
whose entire nature is local in character and confined to a very
limited portion of the anatomy.
In every case coming under this sub-classification, the effect that
the iodine applications have--the only effect that they are able to
accomplish--is one of amelioration; they can have no direct curative
effect here. While the various conditions that are included under this
head will be fully discussed in following chapters, I will point to the
use of topical iodine medication in the handling of a case of parotitis
as an illustration. While regional applications of iodine are the rule,
in the handling of cases of this affection in veterinary patients,
no one at all versed in the condition as it occurs in practice would
give the credit of ultimate cure to the iodine applications. But all
will admit readily that, while the internal treatment indicated by
the pathology of the condition is correcting the lesion _per se_, the
regional applications of iodine do contribute materially to a smooth
termination of the case in that they do, without question, lessen
the possibility of abscess formation, relieve the pain, and hasten
resolution.
The conditions included under this heading form, in great part, that
class of cases to which reference was made in the beginning of this
treatise, namely, those in which iodine treatment is largely used under
circumstances and in conditions that lack almost every scientific
indication for its application. Yet, it is in these very conditions,
and under these very circumstances, that topical applications of
iodine are frequently most salutary in effect. And this effect is
enhanced to the degree, as will be pointed out later, to which the
practitioner becomes adept in the selection of the proper form or
preparation of iodine for the particular case in hand.
3. REGIONAL IODINE APPLICATIONS FOR THE CURE OF CHRONIC PATHOLOGICAL
CONDITIONS.
It is in the correction of chronic pathological conditions, that iodine
therapy finds its greatest field in the practice of veterinary medicine
and surgery. It is in chronic pathological conditions, that iodine,
in various forms, and with various modes of application, so forcibly
demonstrates its therapeutic work, for it is here that iodine is often
the only agent used in the handling of the case, thus constituting the
entire treatment. Under these circumstances, it is never a difficult
matter to decide as to the value of the treatment or the activity of
the agent used.
Were there no other means of demonstrating the fact that iodine, in
some of its forms, arouses the animal organism to the end, and in the
direction, of marked efforts at regional cure of various pathological
states, we would have evidence of ample weight to convince us of this
in the results that we daily get with its application in a general
practice.
There is hardly any therapeutic result from which the practising
veterinarian derives more professional satisfaction than he does
from the sure, gradual effect of properly selected and correctly
applied iodine preparations in chronic pathological conditions of
the articulations, from the speedy and specific effect of others in
certain skin diseases, and from the almost miraculous cure of certain
localized infections when the proper iodine medication is applied in
these.
So sure are the effects of iodine, in a curative way, in certain
diseased conditions among domestic animals, that it has value in this
regard from a diagnostic standpoint. Given a case apparently of this
type for handling, the practitioner can be assured that he has erred in
his diagnosis if iodine, in proper preparation and correct application,
does not effect a cure. To illustrate this, I need only refer to that
diseased condition of the skin commonly termed “ring worm.”
It is nothing unusual, in a veterinary practice, to see the curative
effects of iodine applications demonstrated in certain chronic
conditions, of the articulations for instance, after various other
means of handling, even including surgical interference, had failed
to effect the desired result. In not a few of such conditions, iodine
applications, in some form, are prescribed as a sort of “last resort”
treatment, even against the hopes of either client or practitioner, for
the accomplishment of anything in the way of benefit.
Almost any practitioner of veterinary medicine, with whom you may
care to discuss the matter, can point to case after case, in his own
practice, in which a spavin, or a ring-bone, that had been cauterized
or otherwise operated upon with failure, had yielded to a course
of topical iodine applications. In some instances, a cure of this
sort causes a practitioner to lose faith in operative measures for
the correction of the conditions in question. Usually, however, it
impresses upon him, with added force, the thought that he has not
fully acquired the knack--either along practical or scientific
lines--to select his cases properly. Could he be sure that a given
case would yield to applications of iodine preparations, he would much
prefer to treat it that way; but he is not often sure. He has learned
that there are certain cases, although to all appearances, as far as
he is able to tell, not differing from other cases of the same nature,
will yield to actual cautery; he has learned, also, that certain cases
will yield to local applications of certain iodine preparations. But
he finds it difficult to select these cases for the respective forms
of treatment in the general run of his practice. That he may be better
able to serve his clients, and that he may even more highly appreciate
the therapeutic worth of iodine in some of its forms of preparation, I
have made some clinical observations, in my own practice, which I shall
record in the following chapters, and which, I believe, will help to
solve this problem for him. While it is not possible to pick out every
case in which iodine applications will give the desired result, it is
not an exceptionally difficult matter to select the great majority. It
is the opinion of most veterinary practitioners, who have the ethics
of their profession at heart, that the treatment of certain well-known
pathological conditions of the articulations, by means of the actual
cautery, is one of the most disagreeable features of a veterinary
practice. It is one of the things that most veterinary practitioners
are trying to get away from; it smacks more of quackery and dark-aged
farriery than anything else that the veterinarian is obliged to do.
When, on top of this, we view this form of treatment from the angle
of the humanitarian, we fail to understand why otherwise able and
enlightened practitioners will resort to it under any conditions.
True, there are apparently a few forms--a very few--of equine lameness
that will yield to no other form of treatment. Note, I have said
_apparently_ there are some. I believe, in fact, that any case of
lameness located in an articulation is curable, _if it is curable at
all_, by means other than burning the area with a red-hot iron. While
most of us, in practice, do fire cases of articulation lameness, I
believe that we do so for the reason that frequently it is _for us_ the
easiest way to terminate the conditions connected with the case. And I
further believe that every time we resort to the actual cautery, for
the correction of a lameness in an articulation, we admit, in the fact
that we do so resort, that we do not fully understand the condition we
are attempting to cure. This belief is the result of actual contact
with ample clinical material and the observations made in actual
practice covering a period of time extending over more than fifteen
years.
Other chronic pathological conditions, in which iodine applications
are frequently serviceable, are various new-growths in the integument,
underlying tissues, and in the glandular tissue near the body surface.
It is often possible to accomplish, with topical iodine applications,
results in these conditions which could only be equalled by surgical
interference of much more costly and dangerous character. Iodine
applications are at times resorted to in such conditions as these,
to obviate the scar formation that might result from a surgical
operation. At other times, resort is had to iodine on account of such
objections to surgical interference as cost, danger to the patient’s
life, protracted period of convalescence, or other equally reasonable
objections.
In the effects that are obtained from the local applications of iodine
preparations, in chronic pathological conditions, these preparations
act not only in a palliative or ameliorative sense, but literally in
a curative manner. They accomplish, in these conditions, solely and
wholly through their own activity, the removal of the condition and
the correction of the respective abnormalities. While, in some of the
conditions under discussion, the desired result is attained only after
very prolonged treatment with iodine, the condition is usually of such
a character that neither the owner of the animal nor the attending
veterinarian is averse to lending the time consumed. In other of these
conditions, the desired result comes very promptly, at times with a
rapidity that causes astonishment. In all cases yielding to topical
iodine therapy, sufficient evidence of the beneficial effect derived is
discernible with sufficient promptness to encourage the continuance of
the treatment.