Autopsy

Autopsy Prof. Meng Xiangzhi

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The types of autopsy  Clinical autopsy  Medico-legal autopsy. Its main objective is the

investigation of sudden, suspecious, obscure, unnatural, litigious or criminal deaths.

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The objectives of forensic autopsy  To identify the body and to assess the size, physique

and nourishment.  To determine the cause of death.  To determine the manner of death (suicide,

homicide or accident) and the time of death, where necessary and possible. 3

 To demonstrate all external and internal

abnormalities, malformations and diseases.  To detect, describe and measure injuries.  To obtain samples (blood, urine and tissues) for

microbiological, histological and toxicological analysis.  To retain relevant organs and tissues as evidence.  To obtain photographs and video films for

evidential and teaching use .

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Examination of the scene  In homicide, suspected homicide, and other

suspicious or obscure cases, the examiner should visit the scene of the death before the body is removed. The function of the examiner at the scene of death is generally to assess the local circumstance, the position and the condition of the body; to observe the distribution of blood stains; to identify the suspected weapon, compared with the 5 wound; to pick up physical evidence.

Examination of clothes  The clothes should be examined for damages, blood

stains and other evidence. The contents of the pocket, documents, keys, and other items all assist in identification. The style, fabric, colour and labels of clothes all assist in identification of the individual. 6

 In traumatic deaths, the injuries on the body should

be matched up with damages on the clothes. Tears, slashes, stab wounds and especially bullet hole in the clothes must be compared with the position of external lesions on the body. Blood, seminal, vaginal and other body secretions may be found on the bedsheet, underwear, wall or floor of the house.

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External examination  After identification and removal of any clothes, the

race, sex and age are noted.  The body length is measured from heel to crown.  The body weight is measured if facility is available;

if not it should be estimated. 8

 The general skin color is noted, especially

hypostasis (livor mortis). Congestion or cyanosis of the face, hands and feet is noted. Congenital deformities and acquired external marks (surgical scars) are recorded.  Vomit, froth or blood may be present at the mouth

and nostrils. Faeces and urine may have been voided. Ears are examined for leakage of blood or cerebrospinal fluid. 9

 The degree of rigor mortis is assessed by flexing the

arms and legs to test the resistance. Any abnormal color of livor mortis should be noted.  Recent injuries are carefully examined, measured,

described in terms and photographed.  The eyes must be examined carefully, especially to

detect petechial hemorrhage on the conjunctivae and sclera. The size of the pupils should be recorded. 10

 Examination of mouth may reveal foreign bodies,

drugs, damaged teeth, injured gums and lips, and the bitten tongue of epilepsy or blows on the jaw. Dentures should be identified and removed before autopsy.  The external genitals required careful examination,

especially for the female.

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Skin incision 1. “I”-shaped incision, is an almost straight line from chin to pubic symphysis, deviating to avoid the umbilicus. 2. “Y”-shaped incision. An incision is from the back of each ear to the manubrium of sternum and continue downwards to the pubic symphysis. 12

3. Improved “Y”-shaped incision begins at a point close to the acromial process. It extends down below the breast and across to xiphoid process. A similar incision is then made on the opposite side of the body. From the xiphoid process, the incision is carried downwards to the pubic symphysis.

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 The skin, subcutaneous tissues and fat are flayed off

laterally from the main incision. The tissue are taken back to the lateral edge of the neck and to the outer third of the clavicles. Over the thorax, the tissues, including pectoral muscles, are flayed off to the midaxillary line in the upper part and even further posteriorly towards the costal margin.

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 A small puncture should be made in the peritoneum

and a finger inserted to lift abdominal wall away from the intestines. The knife is then used to cut outwards along the length of the abdomen, to avoid penetrating the intestine.

The abdomen is inspected for the blood, pus or liquid

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The test of pneumothorax  If a pneumothorax has been suspected beforehand,

the chest wall can be punctured in the midaxillary line after filling the reflected skin with water to observe if there are bubbles escaping.

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Opening the thorax  In children and young adults, the costal cartilages

can be cut through with a knife. But in old age persons, the ribs should be severed with a handsaw. Then the sternoclavicular joints can be disarticulated by the knife. The sternoclavicular joint can be identified by moving the shoulder tip with one hand. 17

 When the sternum and medial rib segments are free,

the section is lifted and dissected away from the mediastinum, keeping the knife close to the bone to avoid cutting the pericardium.  The pleural cavities are inspected for adhesion,

effusion, pus and blood. If there is any, it should be measured and recorded.

Sometimes, the liquid should be taken and sent for lab .

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Open the pericardial cavity  The pericardium is opened in a shape of “Y”, and

the pericardial cavity is examined for liquid. The blood sample can be drawn from inferior vena cava.

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Removal of the thoracic contents  The neck structures are then freed by passing a knife

under the skin of the upper neck until it enters the floor of the mouth. The knife is then run around the inside of the mandible to free the tongue. The tissue at the back and sides of the pharynx are cut.

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 Fingers are then inserted from the floor of mouth to

grasp the tongue, which is then drawn down, the remaining tissues behind the larynx being cut to release the neck structures.  The subclavian bundles of vessels and nerves are

severed at the medial ends of the clavicles and first ribs to release the trachea and oesophagus.

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 With gentle traction, the neck structures are held up

and pulled, whilst carefully cutting all attachments to the thoracic spine with the knife. The oesophagus, thoracic aorta and inferior vena cava are severed just above the diaphragm, so that the neck organs and thoracic organs can be freed.

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Removal of the heart  The heart is held up so that its attachment is tensed

against the other organs. A knife is then introduced at the reflection of the pericardium, cutting through the root of the aorta and other great vessels just above the atria. 23

Examining the tongue  The tongue is cut to examine if there is bleeding or

bitten wound, which is usually present in the epilepsy patient.

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Examining the esophagus and trachea

 The esophagus is opened from the lower end to the

larynx, looking for tablet, bleeding spot etc. The trachea and main bronchi are opened to inspect obstruction or any abnormality.

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Examining the heart  The heart is washed and then the general size, shape

should be noted. The heart is opened along the bloodstream. The right atrium is opened by introducing the scissors into the inferior vena cava and cutting to the superior vena cava. Then the right ventricle is opened by cutting along the right edge of heart, so the tricuspid can be inspected.

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 The pulmonary artery is opened by cutting from the

cardiac apex to the trunk of pulmonary artery, and the pulmonary valve can be inspected. The pulmonary vein is opened to expose the left atrium. Fingers are introduced down through the mitral valve to estimate its size and detect any stenosis. A cut is along the left edge of heart. From the cardiac apex, along the outflow tract, the scissors are passed up at the side of the mitral valve, and the aortic valve opened.

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 The blood in the heart is washed and the weight of

heart is measured. After weighting, the endocardium and valves are examined.  The perimeter of valves and the thick of left

ventricle wall are measured. The interatrial septum and interventricular septum are inspected against light for defect.

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 The ostium of left and right coronary artery are

examined for variation and obstruction. Then the anterior descending branch, right coronary artery and left circumflex are cut across at frequent intervals not more than 3mm to observe there is any thrombus or atheromatous plaque. The cut should be started as close to the ostium as possible, as occlusion and serious stenosis can occur very near the origin. 29

Removal of the intestine  The rectum is identified and cut. Then the colon and

small intestines are stripped out by cutting along the mesentery near the attachment until the uppermost part of jejunum is reached.

The intestine is opened along the opposite side of mes

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Examining the spleen  The spleen is removed by cutting through its

pedicle. After weighting, it is sliced in its long axis.

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Examining the stomach, liver, gall bladd  The liver, stomach, duodenum and pancreas are

removed together. The stomach is opened from the greater curvature, and the contents in stomach is measured and collected for toxicological examination. The biliary tract is examined by squeezing the gall bladder to see if there is any bile effusing from the bulb of duodenum. Then the gall bladder is opened to see if there is gallstone. 32

Examining the kidney  The kidneys are freed from their hilums and the

perirenal fat is stripped. Then hold the kidney in left hand and cut it from the cortex border to the hilum, so as to split in half and open renal pelvis. The renal pelvis is exmined for stone. 33

Drawn the urine  The urine can be drawn from urinary bladder with

syringe. If it is difficult, open the urinary bladder.

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Removal of the brain  The scalp is incised from a point behind the ear,

through the posterior vertex, to the corresponding place on the other side. The scalp and subcutaneous tissue are reflected respectively forwards to the lower forehead and back to the occiput. The deep scalp tissues can be peeled off by traction. If it is difficult, the knife is needed to free them.

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 The skull is sawn through, using either hand or

power saw. The calvarium is then removed to expose the dura. The dura is removed after inspection. Two fingers slipped beneath each frontal lobe. With gentle traction, the frontal lobes are lifted back to expose the optic chiasma and anterior cranial nerves. Then a scalpel is introduced to cut the cranial nerves until the free edges of the tentorium are accessible.

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 A cut is made along each side of the tentorium.

Pulling brain back, then the remaining posterior cranial nerves are cut. Finally, the scalpel is inserted down into the foramen magnum to transect the spinal cord as far down as it can be reached. The right hand of examiner is now slid under the base of the brain, pulling the whole brain out, any attached dura being severed where necessary. 37

The fixation of brain  The brain is suspended by a thread passed under the

basilar artery and tied to a support across the mouth of the container, which contains 10 percent buffered formalin, so that the vertex does not touch the bottom of container. Because the surface of brain may be distorted when it touches the bottom. 38