Text from Directions
for making anatomical preparations: formed on the basis of
Pole, Marjolin and Breschet, and including the new method of Mr. Swan
(1831) by Usher Pole.
Preface
That a minute knowledge of anatomy is essential to success
in the practice of physic and surgery, is an opinion so generally prevalent,
that the assertion of it at the present day wears the air of a truism. Every
student reads the remark in his books, hears it from his lecturer, sees its
force in the clinical rounds of his instructor, and feels it when he commences
practice. And if the young practitioner feels the want of anatomical knowledge
when he has recently left the dissecting table and the halls of demonstration,
how much more sensible must he be of it, after years have elapsed, without
affording him an opportunity to refresh his memory by lectures or dissections.
To obviate this inconvenience, various modes have been employed for preserving
the different organs and textures, in a humid or dry state, to which the
practitioner may refer as a substitute for recent dissection and demonstration;
with this aim in view, the art of making anatomical preparations has been
cultivated with great success and advantage.
The art is of modern invention. Injecting and preparing of
the blood vessels certainly could not have been known prior to the discovery of
the circulation of the blood, nor have we any description of arterial
preparations until the time of Ruysch, a professor of anatomy who died in 1731.
His first anatomical museum was sold to Peter the Great, in 1717, and many
specimens belonging to it, as well as a great number made subsequently, are
still in a good state of preservation. His manner of preparing wet
specimens,—of injecting the blood vessels, and of preserving the flexibility of
dried preparations, although he professed to have disclosed it, is supposed to
have perished with him, since no one has yet succeeded in imitations that can
be compared with those made by himself.
Still however the common process for making and preserving
injected preparations bears the name of Ruysch, and to this process many
additions and improvements have been made by Dumeril, Breschet, Hunter, Pole,
Marjolin, Charles Bell, Cloquet, Swan and some others, besides several valuable
treatises on the art of injecting the lymphatics, and numerous facts and
observations, are contained in periodical publications. The substance of the
following sheets, is principally drawn from the above writers, but chiefly from
Pole, to which are added, such facts as I could glean from some of the best
practical anatomists of this country, and such observations as I have been able
to collect during a year passed in the medical schools of Europe, and several
years devoted to practical anatomy in this country.
That a work like the present is wanted, appears evident from
the fact, that several teachers of anatomy have contemplated publishing an
edition of Pole, notwithstanding its numerous imperfections. I should however
not have commenced the present work, had that of Pole been in circulation in
this country. The few copies to be found are imported, and I have several times
been at pains to order copies for my friends from London.
Such a work will, I am confident, be acceptable to students
from the country, as by following its directions, they will be able to preserve
the dissections made at medical schools, as memorials of their industry, and
for reference in their future practice. Even in cities, where subjects are easily
obtained and dissected, and where public demonstrations are frequent, a student
feels reluctant to destroy a fine piece of dissection that has cost him long
protracted labour and pains to finish, although he may expect to derive but
little advantage from its preservation; but in the country, where such
specimens are the best, if not the only means he can enjoy for refreshing his
memory, they possess a real and practical value; for, with the exception of
Massachusetts, whose legislature has nobly raised its voice in favour of
practical anatomy, prejudice and legal impediments it is to be feared will long
exist against its prosecution throughout the union, and especially in our
country towns.
INTRODUCTION.
SEASON FOR DISSECTING AND
FOR MAKING DRY PREPARATIONS.
The extremes of heat and cold are unfavourable for
dissections and making preparations, heat being the season for insects and
rapid putrefaction, and* cold congeals the subject, the subsequent thawing of
which is attended with loss of time, hastens decomposition, and always impairs
the beauty of the preparations. But the objections to midwinter are removed
where the accommodations are such as to moderate the intensity of cold. The
late autumnal and early spring months are, however, decidedly preferable for
long continued dissections; and it is well known to those who are conversant
with the business, that for preserving subjects from decomposition, spring at
the same temperature, is more favorable than autumn. These remarks however,
refer to preparations requiring long and patient dissection; for other kinds,
as macerated and corroded, the summer season may be even preferable.
DISEASES OCCASIONED BY DISSECTIONS.
Besides the diseases that may proceed from contagious
affections of dead bodies and which every anatomist will know how to avoid,
there are two pertaining to a dissecting room that require some notice. One of
them is derangement of the stomach, sometimes attended with fever, and which is
probably occasioned by putrid inhalations, perhaps by errors in diet and long
exposure to cold, and is more common to ardent beginners; the other is
extensive and severe inflammation from slight wounds of the fingers, and
absorption of poison from the subject. B
The former affection may be prevented, first, by proper
attention to diet, never visiting nor remaining in the dissecting room with an
empty stomach ; by nutritious well seasoned food and considerable exercise of
the body in the open air, and by obviating a costive habit. Secondly, by
attention to the air of the room both as respects temperature and cleanliness.
The large cavities of a subject when cleared of their viscera may be sponged
with clean water and sprinkled with chlorate of lime and the room freely
ventilated.—When the emanations are very putrid and offensive, they may be
entirely removed by a fumigating mixture like the following:
.Black oxide of manganese and common salt pulverised, equal
parts, by weight, to which add sulphuric acid, diluted with three parts of
water in a leaden or earthen vessel. Close the dissecting room, leaving the
mixture in the centre of it in the evening, and by morning, the putrid smell
will be entirely removed.
Attention should also be paid to cleanliness of person. An
apron with sleeves to it, made of shalloon, or brown linen, may be worn, and
when this is wanting, a suitable coat to put on and off on entering and leaving
the room may be substituted.
When the symptoms of gastric disturbance which I have
mentioned appear, the dissection should be suspended, for a day or two, and an
active cathartic administered.
The other affection arising from wounds of the fingers is of
a more serious character. Chambar, Percy, Duncan, and Shaw, have each written
treatises of some length on such wounds, from which I shall draw such facts as
are most material to be known. The effects of such wounds, Mr. Duncan and Mr.
Shaw, think, may be classed under two heads, forming cases which differ
essentially from each other. The one is attended with immediate danger, and is
generally the consequence of examining a body a few hours after death ; and
proceeds with more certainty, from dissection of the bodies of persons who have
died with inflammation of some of the serous membranes. The other cases are
more frequent, and less dangerous, and they occur more in common dissections,
and particularly, in preparing bones or ligaments after long maceration. The
symptoms attending this last kind of wound are the following :—the finger being
scratched or pricked in the morning; there is not much pain at the time, but it
gradually increases towards evening; a little uneasiness is felt in the axilla,
and next morning red lines can be perceived running up the arm. The finger is
now excessively painful; there are often slight rigors, and general uneasiness
; the countenance is anxious, tongue sometimes furred, and head-ache; but there
is not much fever. The finger then becomes rapidly swollen and livid, so as to
call for immediate attention, and the general system still more and more
affected.
In respect to the first, or malignant kind, which is more
likely to occur from examining a body that has died from peritonitis, in the
form of hernia and puerperal fever; or from pleurisy, there will, in five or
six hours after receiving a scratch or puncture be a small pimple, or a blush
of red. If the case proceeds in the usual manner, there will probably be a
darting pain up the arm, which seems to fix more particularly in the shoulder
or side of the chest. Within fourteen hours, the patient is very ill; he
suffers a great deal of pain, and is anxious and alarmed. Red lines may
generally be perceived running from the hand towards the axilla, but it
sometimes happens that there are no marks on the arm, nor even on the finger.
Indeed, the affection of the finger is occasionally so slight, "that it is
neglected, and the patient refers all his suffering to the shoulder and chest.
Vessications often appear, and the case may end in desquamation of the cuticle,
or in suppuration with extensive sloughing, and a discharge of fetid matter,
and in many instances, it proves fatal."
The local treatment of both kinds of the above mentioned
wounds, should be the same, at the moment they are inflicted. It consists in
applying to the wound a drop of strong mineral acid or of caustic ;—the French
prefer liquid muriate of antimony. But after this has been neglected, and
absorption has taken place, indicated by pain, &c. such applications will
be of no avail, and may aggravate inflammation. The best applications will then
be of the soothing kind. Mr. Shaw recommends lint soaked in equal parts of
Goulard's extract and laudanum, applied round the finger and along the arm.
Emolient cataplasms are also recommended, but their weight gives pain and
uneasiness. The French recommend leeches to the part.
According to the same authors, the general treatment should
be active aperients, such as rhubarb and jalap, with a little calomel, and to
keep the patient at first almost in a state of intoxication, by laudanum and
porter. Bleeding, although the pulse be much accelerated, he condemns.
Should any abrasion or sore previously exist on the fingers
of the dissector, the utmost care should be taken to shield it from the contact
of the dead body, by proper dressing and a slip of bladder bound over it.
CHOICE OF SUBJECTS.
This must, of course, vary according to the kind of
preparation intended to be made. For a perfect skeleton, the subject should be
near, or a little passed, middle age, for if younger, the bones are not so
fully developed, and in old age they contain oil, which is constantly appearing
upon their surface. For exhibiting osteogeny, choose the bones of a foetus; and
for showing the vascularity of bones with minute injection, the bones of a
young child are preferable ;—To make a preparation of the bones of the head
separately, choose the bones of a young subject, before the age of puberty, and
for the ossiculae of the ear, a child from birth to one or two years. The
tympanum should here be preserved on one side, and partially removed on the other,
taking care to preserve its centre, where the maleus is attached. For
exhibiting the labyrinth by filing into the petrous portion, the temporal bone
of an adult will be best. For exhibiting the deciduous and permanent teeth,
choose the head of a child from five to eight years old, and file away the
alveolar covering of the front teeth.
To dissect and study the muscles, choose a robust, full
grown subject that has died suddenly, and a male in preference to a female. For
making dry preparations of the muscles, take a subject of a strong muscular
frame, whose death was occasioned by a short, but not putrid disease. Great
corpulency, as well as great leanness, and dropsical subjects, are for obvious
reasons unsuitable.
For dissecting and studying the arteries and veins, choose
an adult that is neither very plethoric nor very lean. For making a dry
preparation of the blood-vessels of an entire body, an emaciated subject, from
two to fourteen years is preferable, as being more easily dissected and dried,
and more conveniently handled, and less likely to become greasy after it is
varnished :—For a head or extremities, an adult not much beyond middle age, as
after this period there will be a constant issuing of fat upon the surface,
that will mar the beauty of the preparation; but as the veins are more
developed in advanced age, such subjects are best for shewing them upon the
head. For minute injection, a full grown foetus is best, and may at the same
time serve for exhibiting the foetal circulation, and for making many handsome
preparations, to be hereafter described.
For a wet or dry preparation of the cerebral nerves, choose
an adult emaciated subject, of almost any age;— but for the whole nervous
system, a small emaciated subject, as it can be more conveniently preserved in
spirit.
For the lymphatics choose a full grown dropsical subject.
SURGICAL OPERATIONS.
Whatever be the kind of subject that has fallen into the
hands of the student, and whatever may be his purpose as to its final
destination, he should first perform such little operations upon it, as can be
done without injuring it for injecting, and which he may be desirous of
performing with dexterity upon the living body; such as introducing the
catheter and probing ;—passing a fine wire into the puncta lachrymalia, and
introducing a probe from the lachrymal sack through the nasal duct;—pinching up
the tunica conjunctiva with a pair of small forceps and clipping it with
scissors, as is often required for severe opthalmia. After the subject is
injected, he may take up the various arteries, as the carotid, subclavian,
axillary, external iliac, and those of the extremities. He may also operate for
hare-lip, perform bronchotomy, &c.
ORDER OF EXAMINATION OF THE LARGE CAVITIES.
The tendency of the brain and other viscera of the large
cavities to rapid putrefaction, requires their early removal. The brain
mollifies so soon, that if the student intends examining it minutely, or to
make a wet preparation of it, no time is to be lost by delaying the undertaking.
The next organs to be examined and removed, are, the
abdominal viscera, as their presence hastens decomposition. For this purpose
make a crucial incision from the sternum to the pubis, and cross it with
another near the umbilicus. In this way the viscera are more easily examined
and removed, but the abdominal muscles are in some measure destroyed for
dissection. Such however is the intricacy of this piece of dissection, that the
student will hardly undertake it at first; and the parts most interesting to the
surgical pupil, as the abdominal ring and surrounding ligaments, are uninjured
by it. The viscera are to be examined in their natural situation, and then
after passing a ligature round the O3sophagus below the diaphragm, and round
the rectum, they are to be removed, by dividing the suspensory ligament of the
liver, turning it down from the diaphragm, dividing the oesophagus above the
ligature, and raising the stomach, spleen and pancreas, leaving the branches of
the coeliac and mesenteric arteries as long as practicable. The viscera may be
subsequently examined, and made into separate preparations, as hereafter
directed.
The chest, it is presumed, has already been opened for the
purpose of injecting the subject, if not, proceed as directed for injecting the
arteries, and remove such organs as are intended not to be preserved in
connexion with the walls of the thorax.
The contents of the pelvis are to be removed, by dissecting
the kidneys and passing them downward, or, by dividing the ureters, and dissecting
round the several organs down to the sphincter ani. But if it is intended to
preserve these organs in connexion with the pelvis ; the rectum is to be
cleared and stuffed with curled hair, or oiled wool.
The subject may now be dissected entire, or it may be
divided among a class of four or five persons.
MUSCULAR DISSECTIONS.
Before he commences dissections, the student is presumed to
be well acquainted with the skeleton. He is to begin his work by making an
incision through the integuments, down to the muscles of each limb, commencing
it near the trunk and extending it along in the direction of the large muscles.
The limb or part dissected should be so placed as to keep the fibres of the
muscles in a state of gentle extension. The integuments are to be raised from
the muscles, by drawing them aside, and laying the edge of the knife obliquely
upon and in direction of the fibres, in order that all cellular substance may
be removed without dividing them. The knife may be held in the fingers like a
pen, and moved by them, rather than with the wrist or arm. After removing the
integuments over muscles, all the cellular substance between them is to be
dissected out, taking care not to divide the large nerves or blood-vessels, or
such of their branches as are interesting in surgery. When the superficial
layer of muscles is fairly cleared of adipose substance, they may be raised or
turned aside with hooks, or divided in the middle and turned back, for the
purpose of exposing the deep-seated ones for dissection. The integuments ,are
to be raised from the muscles no farther at a time than is necessary for the
present dissection, and should afterwards be replaced upon the part, to keep it
from drying and to protect it from dust; and in warm weather the whole should be
covered during the interim of dissection with a wet cloth, to keep it cool by
evaporation.
It should be the object of the student to examine the
muscles separately and in classes, according to their respective offices; to
study their situation and direction with respect to the arteries and nerves,
and other parts that are concerned in surgery. If not intended to be preserved,
the muscles may after full dissection be removed, and the ligaments and
structure of the joints examined, before the bones are immersed for maceration.
The student will hardly find it advantageous to make dry
preparations of the muscles alone. They require as much attention, and are
attended with as great expense, as when prepared with the blood-vessels, and
unless he adopts the method of Mr. Swan hereafter described they will change in
colour and size so much by drying, as to represent a recent dissection less
satisfactorily than good plates.
COMPARATIVE VALUE OF COLD AND
WARM INJECTION.
The comparative value of the two kinds of injection depends
somewhat upon the kind of preparation intended to be made. For corroded
preparations the cold injection is entirely unsuitable. For wet preparations it
is immaterial which kind is used, excepting that the warm kind is attended with
loss of time and expense. For common dissections, the cold injection is in most
respects preferable, not only on account of the trouble and expense saved in
heating the subject, and its not heating and crisping the aorta to the risk of
its strength, but also for its withstanding the greatest heat of summer, when
the warm kind is apt to liquefy and ooze out from the orifices of divided
branches. There is, however, a greater smoothness of the vessels that have been
filled with the warm kind, which is pleasing to the eye of an anatomist. In
respect to fineness, they will, either of them, if properly conducted, answer
every purpose for surgical reference, though beyond this, I have found the cold
injection succeed better than the warm, especially for filling vessels of the
hollow organs, and of the membranes of the large cavities. Therefore as
respects utility and convenience I should, except for corroded preparations,
prefer the cold injection.
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