THE AUTOPSY OF THE NEW-BORN.
I. METHODS OF EXAMINATION.
The =Section of the New-Born= differs from that of the adult in
several particulars, as follows:—
_a. Spinal Cord._ The spinal canal may be opened with the scissors
alone, as the soft, bony structures of the spinal column are easily
cut.
_b. Skull._ The cranium is opened, after the removal of the scalp,
in the usual way, by cutting with the scissors into the posterior
angle of the anterior fontanel and then introducing the shears into
the longitudinal sinus, and cutting the latter posteriorly in the
line of the sagittal suture. The sinus is then opened anteriorly.
The sutures between the frontal and parietal bones, and between the
parietal and occipital bones, are now cut with the shears down to
the level of the greatest circumference of the cranium. The cranial
bones with the adherent dura are then pressed outward from the
brain, and are either held in this position or cut through with the
bone-shears so that sufficient room for the removal of the brain is
afforded. The anterior falx is then cut and the brain removed as in
the adult, using great care because of its very soft consistence.
When too soft to be removed the brain may be opened within the skull;
or a horizontal section may be made with the large, flat brain knife
at the level of greatest circumference. Some prosectors freeze the
brain before removal, or remove it while the cadaver is immersed in a
strong solution of brine.
_c. Section of Thorax, Neck-organs and Abdomen._ A small block of
wood is placed beneath the lumbar vertebræ, and the main-incision
reaching from thyroid cartilage to the pelvic crest is made, the
incision passing to the left of the umbilicus, and diverging outward
below it so as not to cut the left umbilical artery. The incision is
now extended through the abdominal wall into the peritoneal cavity,
the right half of the abdominal wall turned up so as to expose the
umbilical vein, which is cut loose from the abdominal wall, so
that a second diverging incision can be made through the abdominal
wall, beginning just above the umbilicus and passing down to the
right of the right umbilical artery, without cutting the umbilical
vein. There is left between the two diverging cuts a triangular
flap of abdominal wall (see Fig. 47) containing the umbilicus,
urachus and umbilical arteries, and connected with the liver by the
umbilical vein. The umbilical vessels are then probed and examined
by transverse sections; and the triangular flap of abdominal wall
turned down over the pubis. After the height of the diaphragm has
been noted the thorax is opened by cutting the ribs outside of the
costochondral articulations so as to give more room. The thymus gland
is then examined and removed. The heart may be opened in the same
way as in the adult, extending the cut into the pulmonary artery up
to the ductus arteriosus, which is examined by the probe. The ductus
arteriosus is easily found by cutting the pulmonary artery in the
middle of its anterior wall. In the median line beyond the right and
left branches of the pulmonary artery is the opening of the duct,
which can be probed into the descending aorta. (See Fig. 48.) The
heart may then be removed, and the foramen ovale carefully examined.
[Illustration:
FIG. 47.—Method of opening the abdomen in the new-born, with
especial reference to the examination of the umbilical vessels.
Note triangular flap, including umbilicus, urachus and umbilical
arteries, and attached to umbilical vein. (After Nauwerck.)
]
[Illustration:
FIG. 48.—Section of pulmonary artery and pulmonary ring in the
new-born, showing openings of right and left pulmonary arteries and
ductus arteriosus (containing probe). (After Nauwerck.)
]
[Illustration: FIG. 49.—Method of demonstrating the Béclard center of
ossification in the lower epiphysis of the femur. (After Nauwerck.)]
It is usually better to take out the neck and thoracic organs _en
masse_ and examine on the table. This must always be done in cases
of suspected thymic death and when the question of the child having
been born alive or dead is to be settled. The position of the
diaphragm must be taken before the thorax is opened. The upper air
passages are then ligated. The thoracic cavity is then opened; the
pericardium and heart opened and examined. The larynx and trachea
are opened above the ligature, and the whole respiratory tract with
the ligature in position is removed from the thorax and placed in a
vessel of clean water. The air passages below the ligature are then
opened, and the lungs, after their floating power has been tested,
are cut beneath the water in order to see if air-bubbles arise from
the cut-surface or from the bronchioles. The lungs are examined piece
by piece for air-containing portions, noting their floating power,
crepitation, occurrence of bubbles, etc. In the case of suspected
thymic enlargement the trachea should be explored from above for a
stenosis, before the thorax is opened. If evidences of pressure upon
the trachea cannot be demonstrated in this way the body of the child
can be fixed in formalin and then opened. The thymus and trachea are
then examined by means of transverse sections. The stomach should be
ligated at both ends and then removed, and opened under water. The
presence of air points to extra-uterine “swallowing” movements. This
test is worthless if decomposition has set in. When the thoracic
organs are taken out _en masse_ the ductus arteriosus can be examined
from the aorta. The removal of neck, thoracic and abdominal organs
_en masse_ is often of advantage in the examination of the infant
cadaver, as the organs can be much more easily examined on the table
than in the body. The neck organs are first removed after ligating
trachea and œsophagus, and with the thoracic organs are stripped down
to the diaphragm and then lifted up out of the body and laid over
the left side of the body. The diaphragm is then cut laterally and
posteriorly. The rectum is ligated and cut between ligatures. The
crura of the diaphragm, the cœliac vessels and root of mesentery are
then cut, and the viscera, including the kidneys, are stripped down
to the brim of the pelvis, where the peritoneum and blood-vessels are
cut.
The _ear-test_ (the demonstration of the opening-up of the Eustachian
tube and middle ear by the establishment of respiration) may be shown
by the examination of the middle-ear from the cranium. The ear-drum
must be examined to see if it is intact.
The _Béclard center of ossification_ in the lower epiphysis of the
femur is examined by opening the knee-joint, flexing the leg, and
then making parallel transverse cuts perpendicularly to the long
axis of the bone, until the greatest diameter of the center of
ossification is cut.
The eye-ball may be removed and examined for the pupillary membrane.
The eye is cut through a few millimetres back of the cornea, the
anterior segment is fixed in dilute chromic acid or alcohol and then
examined microscopically; or it can be examined in the fresh state,
the membrane being visible even to the naked eye.
Bacteriologic examinations should be made in the usual way, the
material being secured by sterile pipette, sterilized knife or
platinum loop, smears, etc. In the examination of a very fresh
cadaver the possibility of danger from infection with syphilis must
always be borne in mind.
II. POINTS TO BE NOTED IN THE SECTION OF THE NEW-BORN.
Aside from establishing the cause of death, the autopsy of the
new-born has for its aim the determination of the age of the infant,
its viability and whether it was born living or dead. Special
attention must therefore be paid to all points that may be of value
in settling these questions.
The _average length_ of a full-term new-born child is 50 cm. (42-58
cm.), boys being somewhat longer than girls; 58 cm. may be taken
as the maximal length, 48 cm. the minimal. Both length and weight
vary within wide limits. The length of the fetus in the first five
months of intra-uterine life corresponds approximately to the square
of the month. In the last five months the age of the fetus equals
approximately the length in centimetres divided by five. Viability
is usually regarded as beginning in the eighth month and with a
body-length of over 32 cm. The _average weight_ of the full-term
new-born is 3,200 grms., for boys 3,310 grms., girls 3,230 grms.;
maximum weight 5,500 grms., minimal 2,500. The weights for the
different months are: second month, 4 grms., third month 5-20 grms.,
fourth 120 grms., fifth 284 grms., sixth 434 grms., seventh 1,218
grms., eighth 1,549 grms., ninth 1,971 grms., tenth 2,334 grms.
Look for traces of _vernix cascosa_. The _skin_ of the
well-nourished, full-term, new-born is smooth, not wrinkled, white
or grayish-red rather than red in color (a slight icteric tint is so
common as to be regarded as normal), and showing the fine _lanugo
hair_ only on the shoulders. The _hair_ of the scalp averages 2-3
cm. in length. The _finger-nails_ are firm, horny and extend beyond
the finger-tips. The subcutaneous panniculus should be abundant. The
average length of the _umbilical cord_ is about 50 cm., and it is
inserted about the middle of the body or just below it. As a rule it
is thrown off on about the 5-6th day. The _cartilages of the nose and
ears_ are firm. In male infants the _testicles_ lie in the firm and
wrinkled scrotum (they begin to descend in the seventh month); in the
female the outer _labia_ usually meet, but occasionally the inner
ones are visible. In the seventh and eighth months the _clitoris_
rises above the greater labia. A small amount of blood-stained
discharge is often present in the vagina of the new-born. From the
_mammæ_ of both male and female new-born a whitish turbid fluid
(“Hexenmilch”) can usually be expressed. The _great fontanel_
is 2-2.5 cm. broad, while the posterior one is nearly closed.
The _pupillary membrane_ is absent after the eighth month. The
_ductus arteriosus_ remains open 4-5 days after birth; the _foramen
ovale_ is not completely closed until the second or third month of
extra-uterine life, although by the tenth day the opening is nearly
obliterated. The _center of ossification_ in the lower epiphysis of
the femur should be present and measure 2-9 mm. It is not present in
the eighth month and in a large proportion of cases begins to develop
in the ninth month. Only rarely is it absent in normal full-term
infants. It appears in the bluish-white cartilage as a lenticular
mass of red or reddish-brown color in which the blood-vessels can be
easily seen. It may be absent in congenital rachitis or syphilis, or
in the latter disease it may show the characteristic appearance of
osteochondritis syphilitica.
The head should be examined for the presence of the “_head-tumor_” or
“_caput succedaneum_,” the œdematous swelling of the scalp over the
parietal eminences. Minute hæmorrhages may be present in the tissues.
The tumor usually grows smaller or disappears within 12-48 hours. In
difficult labors a _hœmatoma neonatorum_ may be produced between the
periosteum and bone, usually over the right parietal eminence. It
appears as a circumscribed tumor which may increase after birth and
persists for a long time. As the result of a periostitis ossificans
a wall of bone may be formed about the extravasate, or it may be
encapsulated with small bony plates. After the absorption of the
extravasate the newly-formed bone may persist throughout life in the
form of a “crater-like” or “coral island” elevated circle of bone.
Infection of the hæmatoma not infrequently leads to the formation
of a subperiosteal abscess, purulent infiltration of the cranial
bone and purulent meningitis. The cranium should also be carefully
examined for other evidences of conditions due to the mechanism of
birth, such as the general shape of the head, condition of sutures,
movability of the cranial bones, depressions, over-lapping, etc., of
the cranial bones. Wounds of the scalp and face should be carefully
noted. The circumference of the _cranium_ is 34.5 cm., sagittal
diameter 10-13.5 cm., transverse 8-9.5 cm., diagonal 12-14 cm.
The _brain_ of the infant is normally rosy-red in color, rather
translucent, soft, almost jelly-like, and moist. Tearing of the
pial veins or meningeal arteries during delivery may produce fatal
meningeal hæmorrhages.
The _weights_ of the internal organs are: brain 380 grms., thymus
7-10 grms., heart 20.6 grms., lungs 58 grms., spleen 11.1 grms.,
kidneys together 23.6 grms., testicle 0.8 grm., liver 118 grms. The
_mature placenta_ weighs about 500 grms., and measures 15-20 cm. in
diameter, 3 cm. thick in the middle and 0.5-1 cm. thick at the edge.
In the examination of the abdomen the _color and appearance of the
peritoneum_, _position of abdominal organs_ and _height of diaphragm_
should be noted. Before respiration is established the diaphragm is
at the fourth rib; after respiration is begun it is about one rib
lower on both sides, usually a little lower on the left side than on
the right. The condition of the _umbilicus_ and _umbilical_ vessels
is of great importance (umbilical hæmorrhage, infection, insertion
of cord, line of demarcation, etc.). Note contents, size of lumen,
thickness and character of walls, appearance and moistness of intima.
In umbilical infection the process spreads through the sheaths of the
umbilical arteries rather than of the vein. The infected arteries
contain yellowish-brown purulent thrombi; and the tissues about them
show œdema, hæmorrhages, purulent infiltration or small abscesses.
The perpendicular position of the stomach, the relatively large size
of appendix to that of kidney and spleen, the lobulation of the
kidneys, and the relatively large size of liver and adrenals must be
borne in mind and not be regarded as pathologic. Examine _adrenals_
especially for occurrence of hæemorrhage, infarction and thrombosis.
Look for accessory adrenals (“adrenals of Marchand”) in broad
ligament and along the spermatic cords. Thrombi in the renal and
spermatic vessels are not rare in the new-born. Note occurrence and
degree of _uric-acid infarction of the kidneys_ (formerly supposed
to indicate that child was born alive). Meconium is present in the
large intestine of the child born at term; when prematurely born it
is found only in the small intestine. It is greenish in color and
contains cholesterin, crystals of calcium sulphate, bile-pigment,
desquamated epithelium and granular detritus.
In the examination of the thorax especial attention should be paid to
the _thymus_, noting its size, color, consistence and evidences of
pressure upon underlying structures, particularly upon the trachea.
In death from suffocation small petechiæ are often found in the
thymus and in the serous membranes. The _lungs_ rise up over the
edges of the pericardium and thymus when respiration has occurred,
and their color is a light rose. Areas of atelectasis are bluish. The
unexpanded lungs are brownish-red, firm in consistence and distinctly
lobulated. Air-containing lung floats in water and crepitates, and
gives off bubbles when cut beneath the water. Attempts at artificial
respiration may draw some air into the lungs. Gas-bubbles may be
produced by decomposition. In _white pneumonia_ the lung is pale,
grayish-white and airless. The _larynx_, _trachea_ and _bronchi_ are
to be examined for presence of mucus, amniotic fluid, meconium,
foreign substances, etc. The ligated stomach should also be tested as
to its floating power, and should be opened under water to determine
the presence of air or gas.
The determination of the exact cause of death in the new-born is
often very difficult or impossible. In many cases no adequate
lesions can be found to explain the occurrence of sudden death
in the first days or weeks after birth. Among the more frequent
causes of such deaths are congenital syphilis, asphyxia neonatorum
(cardiac syphilis, presence of amniotic fluid, etc., in respiratory
passages, congenital cardiac lesions, injury to brain, meningeal or
cerebral hæmorrhage, congenital marasmus, intra-uterine infections,
umbilical infections, enlarged thymus, “overlying,” poisoning,
congenital hæmophilia, melaena neonatorum, etc.), adrenal hæmorrhage,
malformations of gastro-intestinal tract, absence of common duct,
nephritis, pneumonia, etc. The most important congenital infections
are syphilis, gonorrhœa, tuberculosis, variola, typhoid, pyogenic
infection, tetanus, measles, scarlatina, influenza, meningitis,
malaria, recurrent fever, pneumococcus, colon bacillus and others,
mostly very rare. Congenital leukæmia has been observed. Numerous
cases of congenital neoplasm have been reported (hæmangioma,
lymphangioma, fibroma, lipoma, neurofibroma, papilloma of the
larynx, adenoma, carcinoma [liver, kidneys, stomach, intestine],
cystic tumors of liver, pancreas, kidneys and ovary, rhabdomyoma or
rhabdomyosarcoma of kidney, heart, etc., adenosarcoma of kidney,
dermoid cysts and various forms of teratomata).
Congenital syphilis is so common and such an important condition in
the new-born that especial search should always be made for evidence
of its presence. Smears of all the organs should be made in the cases
examined soon after death, and either stained or examined at once by
the dark-field method for the presence of the spirochæte. The most
common anatomic manifestations of congenital syphilis are pemphigus,
macules, papules, or maceration of the skin, white pneumonia, cardiac
dilatation due to interstitial myocarditis, interstitial hepatitis,
splenic enlargement and osteochondritis syphilitica. The long bones
should always be examined for the last-named condition; they should
be removed and cut longitudinally. In the boundary between epiphysis
and diaphysis the presence of a yellow, hard zone points to this
condition. The area of ossification is increased, irregular, and
is separated from the bone by the yellowish zone, which in its
earliest stages is soft and cellular, later sclerotic. The area of
proliferating cartilage is also increased and may contain medullary
spaces, showing as red lines. In rachitis the ossification-zone is
wholly or partly wanting, while the zone of proliferating cartilage
is broader and rich in red medullary spaces. In place of the
ossification-zone there may be present a layer of soft, grayish-white
osteoid tissue containing medullary spaces. No sharp line exists
between the different zones.