DEATH AND POST MORTEM CHANGES

DEATH AND POST MORTEM CHANGES

The purpose of life is to propagate life. In every family, from the richest to the poorest ; in every society, from the most civilized to the most primitive, addition of a new member to the family by way of a new birth is rejoiced as a happy occasion, and loss of a member with his or her death is mourned. These two are the occasions where human beings are least hypocrite. Contrary to birth, death is an inevitable happening. Something which is so much inevitable, should not ordinarily cause so much concern. But we know death of a human being concerns us, the fellow human beings, very much. It is more so for the doctors.

A doctor has to (a) prevent death of a person, (b) pronounce a person dead when his life terminates and (c) ascertain the cause of death, time of death etc. Of these, prevention of death is not the concern of this chapter.

DEATH AND POST MORTEM CHANGESComing to the other points, pronouncement of death of a person, though may appear easy, it is not exactly so. Death is the most painful event in a family. The doctor has to inform the relatives of the dead, about this painful event. The information is a tremendous shock, a jolt for the family members. Naturally, the doctor has to be very cautious. He must be satisfied that, the respiration and the circulation of the person, which have stopped, will not start or cannot be started again. It had happened sometimes that, death was declared premature. Such a misdiagnosis may be disastrous for the professional life of the doctor.

Now, then the question arises that, on which basis, the event of death will be decided by the doctor. What is the definition of death ?

Definitions of death:

Legal definition – Law has not tried to define death. By death, Black’s law dictionary means “cessation of life or ceasing to exist”.

Age-long Physicians’ conception of death is “Total stoppage of circulation with consequent cessation of animal and vital function”. These definitions may not solve all legal problems. With the advent of science, now-a-days, maintenance of circulation with artificial aids has become a common event in hospitals. Sustaining life by such artificial maintenance of circulation inherits certain legal implications. The same is true in question of maintenance of respiration, where the patient needs artificial respiration for the continuance of life. The necessity for such artificial circulatory or respiratory aids is that, the natural circulation or respiration may be established after the artificial aid is continued for sometime. But, as it so happens in many cases, natural respiration may not return even after use of artificial respiration for quite a long period, say for a week or two or even more. Hence, contradiction arises, regarding, if at any period the artificial respiratory aid is withdrawn, whether the doctor by such an act will involve himself with the offence of culpable homicide not amounting to murder or at least, if he by such a step makes himself liable for causing death of the patient by rash and negligent act. But then the problem with the doctor is that, with hope he has to apply those artificial life sustaining aids, which may not always give the expected result to revive the patient. Being satisfied that the vital organs will not resume functioning by their own, even if the aids are continued for unlimited period, the doctor has to, at one stage, withdraw these extraneous aids. But on the other side, the relatives of the deceased feel puzzled that, if the doctor hopefully started those artificial aids, then what made him to think otherwise, to withdraw the aids without any additional deterioration in the condition of the patient. Thus, declaration of moment of death is very important legally.

Due to various possible problems in the court of law, about the moment of death of a person, a comprehensive definition of death has been attempted. It is better to designate it as medicolegal definition of death.

MEDICOLEGAL DEFINITION of death — Death is permanent and irreversible cessation of functions of the three interlinked vital systems of the body (the tripod of life), namely, the nervous, circulatory and respiratory systems.

This definition essentially requires that a doctor before going to certify death, must be satisfied that the functions of these systems have ceased permanently and irreversibly. From this definition we also get that, if any of these three systems fails then, other two also will fail (as they are function ally ‘interlinked’). But this definition also in no way helps to take the decision as to when the artificial aids, which are already in use, should be withdrawn or, how long should they continue.

It is a reality that, the artificial aids cannot be continued for an unlimited period. These have to be stopped at some point. In such a crucial and important affair it is better that, if situation is favourable, the decision of permanent withdrawal of the aids should be taken in consultation with another doctor and only after trial for more than twice that, withdrawal of the artificial aids for short periods did not revive the normal functioning of the aided but otherwise failed system or systems.

In ordinary circumstances however, it is sufficient to wait for ten minutes. If no evidence of function of any of these three systems is available for a continuous period of ten minutes, then the patient may be declared dead, because under no circumstances brain cells can maintain molecular life for more than ten minutes, if they do not get the supply of oxygen for that period.

Beyond the need of certification of death for cremation and ritual purposes, declaration of the moment of death has also acquired immense value from a different (therapeutic) point of view i.e. from tissue transplantation point of view. With progress of science there has been a continuous demand for transplantation of healthy tissue or a whole organ from another body to replace a permanently damaged organ of a living subject. This is quite possible with a sparable organ from a healthy individual, as in case of transplantation of a kidney from a living donor. If both kidneys of an individual are functiong healthily then, one of the two can be donated to a person whose both the kidneys are damaged and not functioning. But transplantation of liver or heart is obviously not possible from a living subject. This inspired to explore the possibility of transplantation of tissue or organ from a dead body to a living subject who is in need of the tissue or the organ.

But this proposition of transplanting tissue from a dead body is not possible in case of most of the body organs, due to death of the tissue within a short period of cessation of circulation and respiration.

Somatic and molecular deaths – Deaths commonly referred to with the cessation of the functions of nervous, circulatory and respiratory systems, are also known as somatic deaths or clincal or systemic deaths. With somatic death further supply of oxygen to different organs stops. Due to lack of oxygen supply, individual cells of different tissues or organs die. This death of the individual cells is known as cellular or molecular death. In the absence of circulation and respiration, different cells die their molecular deaths at different times after somatic death. In the series of molecular death, death of brain cells stand first. Within five minutes of stoppage of circulation and respiration, brain cells are to die. Molecular death In muscles starts by the end of the first hour of somatic death and it takes some more hours for all muscle tissues to die. Blood cells and cornea may remain alive for more than 5 hours. Organs like, liver, kidneys and heart die comparatively early. Death of the fibrous tissue occurs late. As a general rule, organs which receive or need more blood supply during life, die early in absence of circulation.

This gap between the somatic and the molecular deaths has helped the process of organ transplantation from dead bodies. For the purpose, tissues like blood or cornea may be removed from a body soon after somatic death. But those organs which are highly vascular, cannot be left till circulation and respiration stop, as lack of oxygenated blood-supply will soon make them unsuitable for the purpose of transplantation. Thus, for transplantation purposes, heart, liver and kidney have to be removed before stoppage of circulation i.e., before occurrence of the “somatic death”. The organ which cannot be used for transplantation is the brain, where cells die within a few minutes of stoppage of circulation or respiration, even though their stoppage may be taken as to have occurred permanently before brain death. Further, if the brain can be kept transplantable or alive by maintaining circulation and respiration, there is no reason why the subject should be taken as going to face inevitable death. But if it becomes certain that, brain has stopped functioning permanently and irreversibly, then by maintaining circulation and respiration artificially, transplantable organs can be suitably removed from such a donor. This possibility gave rise to the necessity of understanding the conception of “brain death”.

Brain death :

As has already been pointed out, death of the brain cells occurs earliest after the stoppage of the circulation. But the process of death may be initiated by the failure of the function of brain i.e., in other words, brain death in some cases initiates the process of the somatic death.

To be more certain about inevitable progress towards somatic death, more weightage is given on the death of the base of the brain where the vital centres are located, than the death of the cerebral cortex, although it is accepted that the vegetative existence will not continue for long after the death of the brain tissue at the cortical level. Thus for applied purposes, brain death has been classified into three types –

i) Cortical death
ii) Brain-stern death
iii) Both cortical and brain stem death.

At the stage of brain death, it is recommended that, for the purpose of removal of tissues or organs from the dying person, for transplantation to a needy person, artificial respiration and circulation may be maintained in those subjects who then may be considered as “living cadavers” due to the fact that brain death has already occurred in them and he is to die in any way, or in other words is virtually dead. In these subjects, respiration and circulation is maintained artificially, only to keep the cells of the organs living, till their removal for transplantation purposes.

Maintenance of blood circulation and rhythmic respiratory movement artificially, for transplantation purposes, is essential after infalliable diagnosis of brain stem death. But the diagnosis of brain stem death need not depend on the scope of application of sophisticated appliances like cerebral angiography or use of E.E.G. machine. Cautious clinical study should be sufficient. The structural and functional damage of the brain stem may be diagnosed from the absence of the following brain-stem reflexes—

1. Absence of corneal reflex
2. Dilated and fixed pupils, not reacting to light
3. Absence of vestibulo-occular reflex
4. Absence of cranial motor nerve responses to painful stimulii
5. Absence of cough reflex
6. Test withdrawal of respiratory aid (ventilator) should cause stoppage of respiration.

Precautions to be taken to avoid misdiagnosis –

1. Some of the clinical signs of brain stem death may be there in hypothermia. Hence, before testing for the above features. the temperature of such subjects should be raised to 35°C.

2. The diagnosis of brain stem death should be reached by a team of doctors, consisting of a neurologist, anaesthesiologist and an experienced doctor of the intensive care unit of the hospital.

3. The patient should be examined by the above team of doctors at least twice, with a reasonable gap of period in between.

4. None of the doctors who participate in the diagnosis of brain-death should have any interest in the transplantation of an organ, removed from the subject.

Suspended Animation (Apparent death)

It sometimes so happens that due to some reasons a person may appear to be dead because of very feeble or minimum functions of his body systems. Even, the functions of the nervous system, circulatory system or the respiratory system may not be perceived by conventional methods, though the person may actually not be dead and the functions of these systems “return” after sometime, either as such or after proper resuscitation. Such a death-like state is known as suspended animation or apparent death. This may occur due to drowning or electrocution. The state of suspended animation or apparent death is said to be practicable. Its practice is popular among the Indian ‘Yogies’ (persons who follow lives of strict principles with physical and mental exercises and restraint). Such people demonstrate their outfit even by being voluntarily buried alive, under the earth for hours. Actually, the circulation etc. do not completely stop but is being maintained in their minimum. When it is practised voluntarily as by yogies, it is called voluntary suspended animation and when it occurs spontaneously as in cases of drowning or electrocution, it is called involuntary suspended animation.

NATURAL DEATH AND SUDDEN DEATH

Natural death means death occurring due to the natural diseased or pathological condition, old age, debility or devitalisation, in which death is not intended or attempted and also does not occur accidentally.

Sudden death is a death which is not known to have been caused by any trauma, poisoning or violent asphyxia, and where death occurs all on a sudden or within 24 hours of the onset of the terminal symptoms.

Thus, by definition sudden deaths are mostly natural deaths where deaths occur immediately or within 24 hours of the onset of the terminal symptoms, which may be totally different from the symptoms, which the patients were having so long. The definition does not essentially exclude or rule out deaths due to means other than natural diseases, but no unnatural cause should be apparent. If the cause is diagnosed or known to be unnatural one, it can’t be termed as sudden death.

The incidents of sudden death is about 10% of all cases of death. Of these again most of the deaths are due to cardiovascular or circulatory causes. Next in frequency are due to respiratory causes.

Of all cases of sudden deaths about 45% are due to pathology in the cardiovascular system, about 20% due to pathology of the respiratory system, about 15% due to central nervous system, about 6% due to alimentary causes, about 4% due to genito-urinary causes and rest 10% are due to miscellaneous causes.

Among the cardiac causes, the most frequent are —

1. Coronary thrombosis and myocardial infarction
2. Stenosis and insufficiency of valves
3. Congenital heart diseases
4. Acute and constrictive pericarditis
5. Degenerative conditions of heart and heart vasculatures
6. Infective conditions of the heart.

Among the respiratory causes, the followings important —

1. Haemoptysis of different origin
2. Diphtheria, influenza, pneumonias and other acute infective conditions
3. Air embolism
4. Oedema glottis
5. Pulmonary oedema
6. Pleural effusion and collapse of the lungs
7. Foreign body in the respiratory passage
8. Lung abscess, neoplasm and other causes.

Among the central nervous system causes, the importants are —

1. Different intra-cranial haemorrhages, thrombosis
2. Meningitis, encephalitis
3. Epilepsy
4. Brain tumour, brain abscess.

Among the gastro-intestinal causes –

1. Haemorrhage in the stomach or the intestine due to various pathological conditions.
2. Strangulation of hernia
3. Acute appendicitis
4. Intestinal obstruction
5. Rupture of liver abscess or enlarged spleen
6. Perforation of the stomach or the intestine
7. Acute haemorrhagic pancreatitis.

Among the genito-urinary causes those mentionable are —

1. Rupture of ectopic pregnancy
2. Toxaemia in pregnancy
3. Uterine haemorrhage due to various reasons
4. Twisting of ovarian cyst
5. Nephrolithiasis
6. Chronic nephritis and other pathological conditions.

Among the miscellaneous causes —

1. Anaphylactic reactions to different drugs
2. Wrong blood transfusion
3. Blood dyscrasias
4. Status thymo-lymphaticus
5. Vagal inhibition of the heart
6. Cerebral malaria.

Of the above causes, some being quite common and being frequently dealt in a medicolegal mortuary, need detail discussion here;

Coronary thrombosis and Myocardial infarction —

These are by far the most frequent causes of sudden death as per definition. Contrary to popular belief, Forensic Pathologists have recorded that, fatal incidence of myocardial infarction is not limited to elderly subjects only. The author has experience to record death due to myocardial infarction with advanced vascular atheroma in an young man of 29 years of age. This is not an isolated observation of the present author. On the other hand, it also must be admitted that in medicolegal investigations, many cases where more convincing cause of death is not available, myocardial involvement is made responsible, in undesirable haste, in presence of some degree atheromatous changes in the coronary vessels.

Further, complication arises in a case of death due to fall from a stair or when a driver dying in a circumstance of vehicular accident, shows infarct in heart, during postmortem examination. It is not easy for a forensic pathologist to infer whether, the fall from the stair or the imminent vehicular accident precipitated or preceded the recent myocardial infarction.

Another problem for the forensic pathologist is to ascertain the time of infarction, in relation to the time of death. The problem lies in the fact that, the postmortem samples of tissues from the dead body are usually collected late which makes the ascertaining of the exact time difficult. When death occurs very rapidly after an attack then tbs problem is more acute, because in those cases the conventional methods of the histological staining may fail to help, due to death, in one hand ane minimum detectable pathological changes due to short period of survival after the infarction of ischaemia, on the other.

Conventional haematoxylin-eosin method, may not be effective for detection of the infarcts of short duration. For this reason, study of blood enzymes and enzyme activities of the heart musculature demonstrable by macroscopic and histochemical methods, along with other sophisticated tests like fluorescent microscopic and electro-microscopic examination of the suspected infarcted heart muscles, have been tried and are still being explored. In the process of diagnosis, the role of the history of the case and the clinical features must not be underestimated.

Hence in these cases, for proper diagnosis guide-lines are —

1. To take history of the case — Narration of the relatives of the deceased should be recorded as to, how the terminal event of death occurred, whether the deceased had any previous attack or was there anything to suggest that he was prone to the attack.

2. The signs and symptoms as narrated by the relatives and friends of the deceased as to how they started and how they progressed, are important.

3. Enzymatic study of blood, particularly for S.G.O.T. (serum glutamic-oxaloacetic transaminase) and S.G.P.T. (serum glutamic-pyruvic trans¬aminase) is not much helpful. The levels of these enzymes increase during and due to the process of infarction of the myocardium, i.e., due to break down of the myocardial cells. On the other hand due to the same process the concentration of these enzymes in the myocardium decreases. But study of blood for these enzymes in postmortem may not be fruitful due to various reasons including the factors which interferes with the proper interpretations of the findings.

4. Macro-chemical study — About 1 cm. thick transverse slices are made across the ventricles which are mildy washed with cold water, so as to just remove the blood stain and not to disturb the enzymes of the cells on the cut surfaces. The slices are then dipped into 1% solution of 2 : 3 : 5 triphenyl-tetrazolium-chloride at pH 8.5, maintained by addition of phosphate buffer and incubated at 37°C for about half an hour. After this period the slices are treated with 10% formol saline which fixes the stain and increases the contrast between the stained non-infarcted and non-stained or less stained infarcted areas and can be preserved as such. This macrotest detects infarction as lack of dehydrogenase on the surface of the infarcted areas. Tissues from thus detected ‘infarcted’ areas can be collected for histological examination.

5. Histological examination —

(a) H.E. (haematoxylin-eosin) method — The change due to infarction is not detectable by this stain before a minimum of 6 hours, when the myocardial fibres appear more eosinophilic and slightly oedematous. But similar changes are also noticed in otherwise healthy heart tissue, due to postmortem autolysis.

(b) Periodic acid schiff reaction—With P.A.S. the infarcted muscle fibres of the heart takes a purplish pink stain, whereas healthy heart tissue appears grey-blue. P.A.S. reaction has an advantage over H. E. staining method in that, it is more specific and hence can be taken as confirmatory of infarction. But this method also has the disadvantage like that of H.E. stain in that, the purplish pink reaction does not develop in cases where death occurs before lapse of about 6 hours after the infarction.

(c) Phosphotungstic acid haematoxylin stain — This method has an advantage over the H.E. stain in that it demonstrates change in the striation pattern of the myocardial fibres which are more certain and recognisable than the changes noticed in H.E. stain method. The change in the pattern of striation of infarcted fibres is also not expected to occur due to postmortem autolysis. But the disadvantage concerning the time required to be lapsed after infarction, cannot be overcome by this method also, which is almost same as in case of H. E. or P.A.S. method.

6. Histochemical examination —

(a) Reduced lactic dehydrogenase is a definite change, detectable histochemically, but the problem is that, it also occurs due to postmortem autolysis (b) Histochemically, succinic dehydroge¬nase is more specific for infarction than autolysis, but the disadvantage is that, it may not be demonstrable even in established cases of infarction (c) Test for malic dehydrogenase stand in between lactic and succinic dehydrogenase in consideration to both the advantage and the disadvantage with them.

Changes may be detectable by histochemical study within 2-3 hours after infarction. For some enzymes, like phosphorylase, changes due to infarction occur within about two minutes after infarction, but the changes are very unstable, which vanish soon after death.

Studies concerning adenosine triphosphatase, glutaminase and a-hydroxybutyric dehydrogenase have some plus points but none is truly encouraging.

7. Fluorescence test

(a) Macro-test – The sliced tissues are dipped into buffered fluorochrome solutions like, acridine orange, coriphosphine or tetracycline solution in distilled water (100000 units in 1 litre). The tissue is then quickly taken out and washed and examined under ultra-violet rays. The normal heart muscle fibres look brown and the infarcted ones appear green with acridine orange. Early infarcts are also detectable by this method.

(b) Fluorescence microscopic test – Either as fixed cryostat section or formalin fixed paraffin section, with acridine orange (0.1%) in phosphate buffer, infarcted tissue gives the same picture as in macro-test, with slight variation due to variation in the period of survival after infarction which is not conspicuous in Macro test.

8. Miscellaneous tests —

(a) Fall of pH in the infarcted muscle, (b) presence of C-reactive protein, (c) Change in the Na+ : K+ ratio from 1 : 3 to 1 : 2.5, oedematous myofibrils and ruptured mitochondria with swelling, are the other acclaimed early findings of infarction of the heart muscle.

Degenerative conditions of heart and heart Vasculatures —

Of the extensive range of degenerative conditions of the myocardium, those important from medicolegal points of view are, due to toxic agents, e.g., chronic alcoholism and conditions due to various nutritional deficiencies.

Metallic poisons like arsenic, mercury, lead, thalium ; inorganic chemicals like phosphorus ; vegetable poisons like nicotine and many other agents may cause degenerative cardio-myopathy, if the exposure is for a considerable period.

Degenerative changes related to starvation, is simple and are in the line of atrophic changes, as occur in other organs in case of starvation. In case of nutritional deficiency like that of vitamin B1, there may be beriberi heart disease. The same problem of the heart may occur in case of nutritional deficiency due to chronic alcoholism. Beriberi heart disease or other heart problems may occur when alcohol is taken in overdose for a prolonged period. There may be dyspnoea, palpitation, sweating, arrhythmia and atrial fibrillation. There may be heart failure, which if mild, as in early cases, need not be very much concerning, if alcohol can be withdrawn. But in severe cases the condition may be irreversible. Where there are such disorders, as in case of nutritional deficiency of thiamine, therapy with the same may be helpful. But in majority of the cases it may not prove rewarding.

Medicolegal aspects

In dealing with such cases, the medicolegist will not only concern himself with the diagnosis of the cause of the changes that occur in the heart musculature, but also to the degree upto which the heart condition can be made responsible in precipitating death, when the immediate cause of death is apparently due to something other, for example some assault or such a circumstance. Sometimes, as in case of cardiomyopathy of industrial origin, question of compensation may arise, where the doctor has to play a very important role in ascertaining the debility or damage caused by the industrial exposure. Cardiomyopathy as such may not cause death but certainly makes the sufferer vulnerable to different adversities like infection, with reduced vitality.

Rest of the cardiac causes usually do not come under the direct purview of the medicolegist, as those conditions do not usually involve any medicolegal problem.

Air Embolism

Air embolism may occur in many cases where there may be direct medicolegal involvement. Air embolism may occur, (1) in case of injury to a large vein, particularly the jugular vein, (2) in case of criminal abortion, when air may enter the circulation through the separated and open placental vessels, (3) in people who work inside tunnels under water, in an environment of compressed air (Caisson’s disease), (4) air may be pushed inside the circulatory system of a person deliberately, to kill the person. 100 ml. of air, if enters the circulation, should usually be fatal. But a much lower quantity, as low as 8 ml. may cause death, if there is a ventricular septal defect or atrial septal defect (patent foramen ovale). Air blocks the vessels at different levels and may cause circulatory obstruction at different levels, causing tissue anoxia. Traumatic air embolism may be either homicidal or accidental, as in case of injury to the jugular vein. During post mortem examination, there may be presence of frothy blood in the chambers of the heart and the vessels with macro and micro changes in the organs involved.

Oedema Glottis

This condition draws medicolegal interest when it is due to inhalation of some corrosive or irritant vapours or due to regurgitation, inhalation of the vomitus in case of ingestion of such poison or due to the parenteral use of some systemic poisons. The condition may also arise due to certain pathological causes. Oedema glottis may cause very rapid death, which is mostly accidental, though in some cases may be homicidal (very very rare occasions of homicidal use of some specific poisons) and in still rare cases may be suicidal in nature. In comparison, natural cases of oedema glottis is much more common.

Pulmonary Oedema

Apart from sudden deaths which are mostly natural in origin, pulmonary oedema may occur due to various reasons like, local action of irritant inhalants or due to systemic action of various asphyxiant poisons. It is a constant finding in case of death due to drowning, particularly, wet drowning. Hence, a case of sudden death due to pulmonary oedema must be dealt very cautiously.

Pleural effusion and collapse of the lungs

In addition to the natural sudden death due to this cause, there may be pleural effusion due to injury to the lungs with simultaneous collapse of the lungs. Pale or serous and chocolate or haemorrhagic pleural effusion are the results of various chronic or subacute pathological conditions of lungs or pleurae. But acute pleural effusion, haemothorax or pyothorax is not uncommon in usual medicolegal practices, e.g., death due to trauma of lungs or pleurae.

Foreign body in the respiratory passage is almost exclusively accidental in nature which causes death by way of choking and asphyxia.

Lung abscess

Apart from various natural causes which come within the definition of sudden death, lung abscess may also occur as a result of infection or lung injury or from inhalation of some corrosive gas. However, most of these cases are natural or pathological in origin.

Different intra-cranial haemorrhages are mostly traumatic in origin. However, natural conditions like, blood dyscrasias, deficiency diseases and arteriosclerotic state of the intracranial vessels may obviously cause intra-cranial haemorrhages at different levels.

Deaths due to epileptic seizure may be natural, but in many instances they may lead to accidental death, for example, death due to drowning and burning during epileptic seizure, occurring while bathing or cooking.

Brain abscess and sometimes a tumour like lesion may be the sequelae of trauma or intracranial injury. But these are mostly natural.

Haemorrhage and perforation of the stomach and the intestine

These may occur in pathological conditions like gastric or duodenal ulcer, oesophageal varices, and due to infective conditions due to salmonella or shigella. Apart from the pathological conditions, haemorrhage may also occur due to trauma of the stomach and intestine, due to ingestion of corrosive or irritant poisons, or if accidentally some mechanical irritant, a piece of broken glass, a nail, a piece of blade or such things are swallowed. Instances are not unknown when, “magic” performers chew and swallow a piece of glass or a shaving blade and later, have to be subjected to operation or even die.

Strangulated hernia, acute appendicitis, intestinal obstruction, rupture of liver abscess or an enlarged spleen, are all purely pathological conditions and as such do not bear any special medicolegal significance. Acute haemorrhagic pancreatitis may be of pathological origin but similar lesions may be observed in death due to exposure to cold.

Rupture of Ectopic pregnancy

Ectopic pregnancy itself is an accidental abnormality. If it is not diagnosed early and proper surgical steps are not taken, then rupture of the fallopian tube or the ovary occurs, if the pregnancy was there, and that may lead to death due to extensive haemorrhage and shock. Rupture of ectopic pregnancy or death due to this, though is a natural pathological phenomenon, may often be caused or precipitated by trauma.

Toxemia in pregnancy

This is purely a pathological condition which if ends in death, should not create much confusion and there is no necessity of medicolegal postmortem examination. As such litigation does not arise in such cases except a charge of negligence on the doctor in some cases.

Uterine haemorrhage

Of the various uterine haemorrhages leading to death, some are of pathological origin like, malignant or non-malignant new growth. But most of them are related with attempted and incomplete abortion where haemorrhage persists and is excessive and leads to death. These conditions are not difficult to diagnose and when death occurs in course of abortion, the issue may come under the purview of sec 314, I.P.C. In these cases there may be accompanying rupture of the uterus with injury to some other internal organs, when an instrument has been used to kill and extract the product of conception.

Twisting of ovarian cyst, nephrolithiasis and chronic nephritis are purely pathological conditions and should not create any problem in their diagnosis, if comes for medicolegal postmortem examination.

Anaphylactic reaction to different drugs

This is not a very uncommon event. Anaphylactic reaction being more severe and fatal in more number of cases when drugs are given parenterally, cautious dealing is the constant demand, both for the interest of the patient’s life and the safety and professional interest of the treating doctor. Some drugs are badly popular as being likely to cause anaphylaxis, like, drugs consisting of foreign serum (anti-snake venom, ATS, ADS etc.), penicillin (parenteral preparation), aspirin, I.V. preparation of iron and many more. The problem in these cases for the autopsy surgeon is that, anaphylactic deaths do not leave much “finger-print” about the cause of death, on the organs or the tissues. Enthusiastic diagnosis by the side of the dissection table should be avoided. During post-mortem examination, viscera, blood, and tissue from the injection site should be preserved. Diagnosis should depend on the history of the case, the general features of shock in the dead body, absence of any obvious cause of death and detection of the drug in blood, viscera and the tissue preserved from the site of the injection.

Wrong blood transfusion

The followings are the dangers from blood transfusion:
1. Mismatched blood transfusion may cause immediate death or death within a short period. But the patient may survive also.
2. Old stock or transfusion of haemolysed blood also cause similar problems.
3. Transfusion of very cold blood (preservation complication), may also be dangerous in the same way.
4. Transfusion of infected or contaminated blood may cause immediate problems as well as delayed problems due to infection.
5. Excessive or rapid transfusion may cause over loading effect on the heart.
6. Repeated blood transfusion may cause certain pathological conditions which are not expected to come under the purview of the medicolegist.

Mismatched blood transfusion

In mismatched blood transfusion there will be shock, fever, rigor, fall of blood pressure, rapid pulse. The patient may die or may be cured with short or long duration complications.

During post mortem examination, clumps of agglutinated R.B.C.s may or may not be detected in the vessels. There will be haemorrhages at different levels of different organs, e.g., in the subendocardium or in the tissue and calyces of the kidneys. Histologically, the tubules of the kidneys will show degenerative changes with R.B.C. in them. There will be haemorrhages under the serous layer of the stomach and at the undersurface of the pleurae.

Materials to be preserved during postmortem examination —

1. Kidneys for histological examination
2. Blood and urine for serological, biochemical, microscopic and spectroscopic tests

In addition to the above materials preserved from the dead body, for proper investigation, the followings should also be preserved –

1. Sample of the blood transfused
2. Sample of the blood of the subject before transfusion
3. Sample of blood of the subject after transfusion (if death has occurred then, sample of blood after transfusion and before death, if available).

In course of investigation, the following points should be given due attention –

1. Whether there has been haemolysis after transfusion and before death. If haemolysis was there, then there would be (a) Presence of haemoglobin in the serum. In case of postmortem haemolysis also, there will be presence of Hb. in the serum. In such case spectroscopic test for meth-haemalbumin should be done. Free haemoglobin changes to hematic during life which combines with the albumin to form meth-haemal¬bumin. (b) In a case where the patient dies after some period, estimation of the serum bilirubin may also be helpful, (c) There will be presence of urobilinogen and urobilin, free haemoglobin and R.B.C. cast in urine, (d) Serological test may detect evidence of neutralisation of the antibody in the serum of the subject by the transfused blood cell antigen. If there was no haemolysis, then the cells of the subject may become sensitized against the antigen of the transfused blood and specific antiglobulin against the serum of the donor’s blood may be formed. Apart from these, group tests of all the samples of the available blood has to be performed.

When old stock or haemolysed blood or very cold blood or infected blood is transfused, more or less similar clinical features are available. The haematological and biochemical picture, both in the blood and the urine may be the same. The histological findings may be less vigorous, particularly in the kidneys and thus microscopic examination of the urine may not show cellular casts. In absence of mismatching, the serological findings mentioned in the earlier paragraph, will not be there.

Due to excessive and rapid transfusion of blood, the heart may be overloaded and there may be cardiovascular failure and death. Post-mortem diagnosis of the actual cause of death in such cases is very difficult.

Blood dyscrasias

Various abnormalities in the blood and its constituents may cause various problems and in some cases sudden death may occur due to some such problems. The history of the case, the terminal signs and symptoms, and when postmortem examination is held, some available findings should be sufficient to come to the decisive diagnosis.

Status Thymo-lymphaticus

This is a condition where the thymus gland remains proportionately larger in a few young boys, in comparison to the girls or other boys of their ages and there is also some evidence of hyperfunction of the thymus with the boys being more childish in appearance than others of their age. There is question about the status or even existence of the condition of thymo-lymphaticus. In some cases, there may be presence of some other interesting findings, like general hyperfunction of lymph glands all around the body and hypofunction of the adrenal glands.

Vagal inhibition of heart (cardiac arrest due to vagal stimulation)

Vagus is a mixed nerve which has motor supply to part of palate, larynx and pharynx and sensory supply to pharynx, oesophagus and rest of the respiratory tract. Among the organs and viscera it supplies are, heart, lungs and stomach. Stimulation of vagus causes inhibition of the heart. If the heart at that stage is in anoxic condition then, there may be cardiac arrest. Cardiac arrest of vagal origin is primarily noticed on the operation table due to insufficient induction or due to low maintenance dose of the anaesthetic agent. Subjects who are over sensitive to vagus are usually prone to such episode. Other vulnerable subjects are those who, have carotid sinus overactivity or are thymolymphaticus young boys. Stimulation of the vagus can cause inhibition of the heart rate in one side and bronchospasm on the other. The heart thus may as well be in a state of anoxia or partial anoxia simultaneously. Thus stimulation of the vagus may quite expectedly cause cardiac arrest. Some persons may become specially prone when the vagus nuclei are stimulated due to painful stimuli carried to the brain through the sensory nerves, as in cases of being kicked on the scrotum, abdomen or hit by a fist blow over the precordial area of the chest or on the neck or during use of instrument inside the vagina or in the respiratory tract. Psychological shock may also give such result.

Cerebral malaria

This is a pernicious variety (complication) of malaria caused by the malaria parasite plasmodium Falciparum. There may be neurogenic disturbance of any variety and magnitude, from drowsiness to coma, twitching of muscles to convulsion, restlessness to mania. There may be hyperpyrexia, dry skin and unequal pupils.

Medicolegal importance — The brief clinical course leading to death, with the stated signs and symptoms, may be confused with heat hyperpyrexia or heat stroke. But the peripheral blood smear picture shows presence of parasitic rings in more than 5% of the R.B.C.s.