**5.5 Examination of the eye**

This may be necessary in cases of non accidental injury, to look for retinal haemorrhage, or in cases of intrauterine infection or suspected retrolental fibroplasia.

#### **5.6 Examination of the musculoskeletal system**

This may be necessary in cases of suspected birth injury, other causes of trauma, congenital deformity, or tumours.

#### **5.7 Examination of the neuromuscular system**

This would be necessary in cases of suspected neuromuscular disorders or metabolic storage disorders.

#### **5.8 Dissection of pelvic organs with continuity of perineum and anus**

This is sometimes when there is suspicion of a urinary tract anomaly or if the external genitalia are ambiguous. The symphysis pubis is bisected with a sharp scalpel. All the connective tissues around the pelvic organs are dissected freeing them anteriorly, posteriorly and sideways. In males, the muscular part of the penis is denuded till the terminal part is reached. The attachment to the glans penis is cut so that the penis can be removed in continuity to the bladder. In females, the skin of the vulva is incised as a circle near the external os. Blunt dissection around the vagina frees the vagina and uterus to be removed. The anus in both sexes, is removed by blunt dissection in a circular manner in the perineum around the anal aperture. Further dissection would allow the anus to be removed with the pelvic organs [2].

#### **5.9 Organ dissection**

All major organs should be accurately weighed after removal, and then compared to normal values. These are produced in terms of both gestational age and body weight, for both live and stillborn babies.

#### **5.10 The cardiovascular system**

If congenital heart disease is suspected, the heart is dissected along the path of blood flow, as for the adult. Careful inspection of the chambers in the manner of blood flow is done. Any defects or asymmetrical findings are noted. Cardiac wall hypertrophy or dilatation is noted for each chamber. The openings of the valves are examined and their diameters are noted. Any fical myocardial lesions should be looked for during examination of the ostia. The whole heart must be preserved for histo-pathological examination.

#### **5.11 The respiratory system**

The hydrostatic test must be undertaken to come at a conclusion regarding life or dead birth. A piece of the liver acts as a control in such cases. If the liver piece floats when placed on water, it means that putrefaction has set in and then there is no utility of this test as false positive results would be expected when the lungs are placed in the water container. The shape, consistency and weight of the lungs should be noted. It is always better to send the lungs for histo-pathology in such cases where a clearer picture would emerge [1].

A rough estimate of foetal maturity can be got from weight of the lungs: body weight ratio: Lung weight: body weight ratio < 0.012: 1 in gestations ≥28 weeks.

Lung weight: body weight ratio < 0.015: 1 in gestations<28 weeks.

Deep dissection of the brochial & pulmonary arteries should be carried out as far as possible. The pulmonary lobes are best dissected in the coronal plane. The lung parenchyma should be examined for consolidation, abscess, haemorrhage, oedema & focal lesions. Small areas of collapse are seen as depressed reddish areas. All pulmonary lobes should be sampled for histology. If a tracheo-oesophageal fistula is suspected, the trachea should be opened anteriorly and the oesophagus dissected distally and attached to the trachea. The trachea and oesophagus should be sampled for histo-pathology preferably at the level of the laryngeal cartilage so as to include thyroid gland in the same block.

#### **5.12 The gastrointestinal system**

It is always better to locate the caecum which forms the boundary between the small & large gut. The entire intestines should be opened and the mucosa examined. The distribution of meconium should also be assessed. The mesentery of the gut should also be examined during autopsy.

The liver should be weighed after removal before being dissected in a coronal plane to allow comparison between the right and left lobes. Any colour change or focal lesions should be noted and both lobes should be sampled for histopathology [7].

The pancreas usually is auto digested before the body reaches the mortuary. However, if present it should also be sent for histo-pathology.

#### *Autopsy in Foetal Infant Deaths DOI: http://dx.doi.org/10.5772/intechopen.92673*

The Genitourinary System: Malformations of the urinary tract are quite common and should be looked for. In males these anomalies are found with obstructive lesions of the urinary tract and may require special attention.

The kidneys should be weighed and dissected coronally. The cortices and medullae should be identified. The renal pelvis and calyces should also be examined. Yellow streaks of urate may be seen and prove neonatal survival. Each kidney should be sampled for histo-pathology [4].

The testes normally lie within the scrotum from 32 weeks of gestation.

#### **5.13 The lymphoreticular system**

The thymus is a part of the anterior mediastinum and is proportionately much larger than in adults and easier to identify. The spleen should be weighed. Any focal lesions in the splenic parenchyma should be identified. Splenic enlargement is seen in haemolytic syndromes. The spleen should be sampled for histo-pathology [1]. Any lymphadenopathy should obviously be identified and sampled for histopathology. Routine histology should include a block of small bowel mesentery which will contain several lymph nodes.

Routine examination of bone marrow is not necessary, but if haematopoietic disturbance is suspected, marrow should be sampled for histology. The ribs is the most approachable and convenient site.

#### **5.14 Precautions**

In regions of high maternal HIV prevalence, autopsy practice using universal precautions will significantly protect against accidental transmission.

#### **5.15 The placenta examination**

Placenta is a vital part of any foetal or perinatal post mortem. Examination of the placenta is also an essential part of the autopsy of a perinatal case. Before starting the dissection, a bacteriological sample should be taken from the placental membranes and parenchyma in cases of stillbirth, prematurity, or IUGR, or if generalised infection is noted. The site of cord insertion must be identified and the length of cord noted. True knots, ruptured varices, and number of vessels must be noted. The vessels themselves should also be sectioned to assess the possibility of thrombus, an important point in identification is that all arterial branches cross superficial to venous branches. The foetal membranes should also be examined, and any meconium staining or discolouration (suggesting infection) noted. The size of the placental sac and the point of rupture should also be noted. The maternal cotyledons should be examined closely. The membranes and cord should then be removed, and the placental disc weighed and measured. Any blood clot received with the placenta should also be weighed. Serial slices should be made through the placental disc at approximately 1-cm intervals, one of which should go through the insertion of the cord. Any focal lesions, such as infarction, thrombosis, and haemangiomata should of course be noted. For histo-pathology, sections of cord, rolled up membranes, and placental parenchyma should be taken, in addition to any lesions identified macroscopically. The placental sections should include cord insertion, placental edge and membrane. In twin or other multiple placentae, the dividing membranes should be carefully examined to assess the number of chorionic and amniotic membranes. Monochorionic placentae indicate monozygosity whereas dichorionic placentae can occur in both homozygous and heterozygous multiple pregnancies. Any

apparent anastomoses of foetal vessels should also be noted. Histological samples should also include the rolled up dividing membrane(s) and/or the placenta at the point of the division(s).
