Regla de los puntos

They may be classified as follows:

A. Immediate Changes

Permanent cessation of circulation and respi- ration. B. Early Changes 1. Changes in eye 2. Changes in skin 3. Cooling of body 4. Post-mortem staining C. Late Changes 1. Rigor mortis 2. Putrefaction 3. Adipocere

Immediate Changes

Permanent Cessation of Circulation and Respiration

Ordinarily, after death there is permanent cessation of circulation and respiration. This is usually ascertained by examination with stethoscope when one cannot hear any breath sounds or heart beat. Ordinarily, life is not compatible if there is no respiratory or heart beat for more than 5 minutes. In the hospital usually 5 minutes of flat ECG line is considered as stoppage of circulation.

But in some cases, a person may be in suspended animation where respiratory and circulatory activity may be at such low pace that it cannot be detected by stethoscope. Such a stage is seen in trance, yoga, hysteria, epilepsy, cholera, drowning, electrocution, tetanus, cold exposure, poisoning by narcotics, surgical shock and anaesthesia. In such cases, a person can be revived by artificial ventilation and cardiac massage. Some animals like frogs go for such stage for a longer time and it is called ‘hibernation’. So, to be sure, one has to apply the following tests to know if Table 7.1 Changes with time in myocardial infarction

Time Gross features Microscopic examination

0-4 hours None None

4-6 hours Pallor is seen Hyalinisation, loss of striations, and eosinophilia is seen

6-9 hours Tigroid appearance of the Necrosis with leukocytic infiltration area looks pale or brownish purple

9-24 hours Necrosed region shows yellow border Advanced necrosis. Leukocytic infiltration seen with hyperemia around border

2- 4 days Necrosed area with yellow border Marked infiltration of neutrophils with advanced which is dry and firm necrosis

5-6 days Yellow area becomes broader Macrophages appear. Removal of necrotic material seen

7th day Whole area becomes yellow Fibroblasts and capillaries start coming in the area. Phagocytosis of muscle fibres begins

2nd Week Periphery appears red Macrophages start removing dead tissue. Collagen found in periphery. Small infarcts heal completely 3rd Week Pale grey Dead tissue removal continues. Collagen becomes

prominent. Eosinophils start decreasing 4-8 weeks Scarring seen as grey or grey-white Collagen increased, vascularity decreased

Medico-legal Aspects of Death 43

1. Magnus Test: A ligature is tightly applied around the base of finger sufficient to cut venous flow but not arterial flow. The finger remains as such if the circulation has ceased. While if a person is having circulation, the portion beyond ligature becomes blue and swollen.

2. Diaphanous Test: If a person is alive, the webs of fingers appear very red and translucent if the hand is held in front of light with fingers abducted. But it appears yellow and opaque after death. But in carbon monoxide poisoning it may appear red, and yellow in anaemia.

3. Icard’s Test: In this, a solution of fluorescein dye is injected into hypodermis. It produces discolouration of skin only if the circulation is there, otherwise not. 4. If the pressure is applied and later withdrawn

on finger nail, it produces, alternately a white and pink colour in live person, otherwise not.

5. If a small artery is cut, there would not be flow of blood in jerks if the person is dead. 6. On application of heat to the skin in a living person it produces a true blister with a clear red line; in dead persons, red line would be absent.

7. If there is no activity on ECG continuously, circulation may be supposed to be stopped. The following are the tests for determining the stoppage of respiration:

1. A mirror is held in front of open mouth and nostril. If it gets hazy, it means respiration is there. This test is more useful in cold weather.

2. If a feather or cotton fibre is kept in front of the nostrils, there would be movement of this if the person is respiring, otherwise not. This test is not much reliable as movement may be there due to air current. Indian Criteria of Brain Death

Death has been defined as total and permanent cessation of all the vital functions; a state of the

body showing complete loss of sensibility and ability to move in which there is complete cessation of functions of the brain, heart and lungs, the so- called “tripod of life”, which maintain life and health. In majority of cases, death is not an event, it is a process; various organs and systems supporting the continuation of life fail and eventually cease altogether to function, successively and at different times. Rarely, death may occur instantaneously or near instantaneously as in cases of massive trauma. Generally, a dying patient passes through the processes of successive organ system failure reaching an irreversible state at which brain death occurs and this is the point of no return. In some cases, brain death does not occur as a result of the failure of other organs and systems but as a direct result of severe damage to the brain itself. Brain death results in cessation of spontaneous respiration followed by cardiac arrest within minutes due to hypoxia. Whatever the mode of its production, brain death represents the stage at which a patient is truly dead, because by then, all functions of the brain have permanently and irreversibly ceased. Since the respiration and heart can be artificially maintained even after brain death it is necessary that we must define the criteria which will identify with certainty the existence of brain death.

The concept of brain death is in consonance with scientific findings and is critical for the purposes of removal and transplantation of human organs. The traditional concept based on cardio- respiratory failure is scientifically inadequate and redefinition is essential for scientific purposes, as well as for purposes of facilitating organ transplantation.

During the past few decades, brain-related criteria in defining death have gained increasing scientific support, statutory recognition and judicial approval in many parts of the world. With the passage of Transplantation of Human Organs Act, 1994, India has also given statutory sanction to the concept of brain stem death. The act defines the “deceased person” as a person in whom permanent disappearance of all evidence of life occurs

44 Concise Textbook of Forensic Medicine and Toxicology irrespective of the immediate cause, whether brain stem death or cardio-pulmonary arrest any time after live birth has taken place. Brain stem death has been defined as the stage at which all functions of the brain stem have permanently and irreversibly ceased. The brain stem death has to be certified by a board of medical experts consisting of the following:

1. The registered medical practitioner in charge of the hospital in which brain stem death has occurred.

2. An independent registered medical practitioner being a specialist to be nominated by a registered medical practitioner specified in clause (i) from the panel of names approved by appropriate authority.

3. A neurologist or a neurosurgeon to be nominated by the registered medical practitioner specified in clause (i) from the panel of names approved by appropriate authority.

4. The registered medical practitioner treating the person whose brain stem death has occurred.

Transplantation of Human Organ Act 1994 was enacted in July 1994 and notification was issued in the Gazette of India on 4 February 1995. With this notification the concept of brain stem death has became operational. According to the Act there are certain preconditions which must be fulfilled before certifying brain stem death or brain death. These are:

1. The cause of irreversible brain damage (whether accident or illness) producing non- responsive coma must be clearly established. 2. The following reversible causes of coma

must be excluded.

(a) Intoxication (alcohol).

(b) Depressant drugs such as barbiturates, benzodiazepines, meprobamate and methaqualone, etc.

(c) Muscle relaxants (neuromuscular blocking agent), e.g. succinylcholine. (d) Primary hypothermia.

(e) Hypovolaemic shock.

(f) Metabolic or endocrine disorders. The patient must be examined by a board of medical experts twice at an interval of 6 hours and brain stem death will be declared only after observing the following points:

1. Coma—the person is comatose and not responding to any painful stimuli.

2. Absence of spontaneous breathing. 3. Pupillary size—bilaterally dilated and fixed. 4. Pupillary light reflex—absent.

5. Corneal reflexes (both sides)—absent. 6. Doll’s eye movement—In a brain dead

person the eyes will move with the head. 7. Motor response in any cranial nerve

distribution; any response to stimulation of face, limb or trunk; there must not be any response in brain dead person.

8. Gag reflex—must be absent.

9. Cough (tracheal) reflex—must be absent. 10. Caloric test: In a normal individual if cold

and warm water is poured in one ear, the eyes will move towards that ear. If there is any abnormality in brain stem the eyes will not move.

11. Apnoea test: The patient is given 100 per cent oxygen through the respirator for 10 minutes and then 5 per cent carbon dioxide is added to oxygen so that there is a maximal stimulus for breathing, followed by passive flow of oxygen at the rate of 6 l/minute through a fine catheter. This procedure allows pCO₂ to rise without hazardous hypoxia. Hypercarbia adequately stimulates respiratory effort within 30 seconds when pCO₂ is greater than 60 mmHg. A 10- minute period of apnoea is usually sufficient to attain this level of hypercarbia. The respirator is disconnected for 10 minutes and the patient is observed for any sign of

Medico-legal Aspects of Death 45

respiratory movement. If there is none, the apnoea test is positive. The test is repeated after 6 hours.

The brain stem death certificate has to be signed by all the members of the board, and the organs from the brain dead person can be removed for use for therapeutic purpose after obtaining the necessary consent for such removal.

Death, as defined in the Indian Penal Code (Section 46): Death denotes the death of a human being unless the contrary appears from context and in Registration of Births and Deaths Act 1969 Sec. 29(B)—as the permanent disappearance of all evidence of life at any time after live birth has taken place. These definitions are clearly inadequate and make the task of the medical practitioner extremely precarious and prone to grave legal consequences.

Redefining death in clear and unambiguous term and making operational the concept of brain stem death, will not only permit transplantation of human organs but is also desirable for the following reasons:

1. Medical:

(a) Discontinuance of treatment.

(b) For optimal utilisation of scarce hospital resources.

(c) To avoid psychological effects on healthcare workers who were looking after the deceased.

(d) Provide legal protection to doctors and nurses who are called upon to withdraw support system in case of a brain dead person.

2. Legal: For purposes of succession and inheritance.

3. Social Factors: To prevent emotional trauma and financial hardship to the members of the family of the brain dead person. 4. Religious: For performing last religious rites.

Recognising brain stem death is a step forward and is in consonance with modern concept.

Early Changes