Different countries have different legal systems because of culture, religion and politics.
Those working within the medical, healthcare and scientific professions arebound by additional laws, rules, standards or regulations specific to their area of practice.
Legal Systems
The law is an expression of the formal institutionalization of the promulgation, adjudication and enforcement of rules.
Criminal courts generally deal predominantly with disputes between the State and individual, and the civil courts with disputes between individuals.
Decisions made by judges in the courts is referred to as common law or case law.
Criminal law
Criminal law is that law which addresses the relationship between the state and the individual.
Criminal trials involve offences that are ‘against the public interest'.
In a criminal trial, it is for the prosecution to prove their case to the jury or the magistrates ‘beyond reasonable doubt'.
Civil law
Civil law is concerned with the resolution of disputes between individuals.
Non-molestation order instructs an individual not to contact, harass, threaten or be violent to another person.
Occupation order prevents someone from, for example, living in or returning to the family home.
The standard of proof in the civil setting is lower than that in the criminal setting.
The penalty is designed to restore the position of the successful claimant to that which they had before the event.
The High Court has unlimited jurisdiction in civil cases and has three divisions: Chancery, Family, and Queen's Bench.
Doctors and other healthcare professionals and the law
Two roles in relation to the court, either as a professional witness or as an expert witness.
The distinction between these roles may be blurred.
In 1924, Dr Graham Grant, a police surgeon differentiated professional from expert witnesses in his book ‘Practical Forensic Medicine'.
Professional witness
A professional witness is one who gives factual evidence.
This role is equivalent to a simple witness of an event.
Expert witness
An expert witness is one who expresses an opinion about medical or scientific matters.
Expert witnesses may also deliver expert evidence within the area of their expertise.
Their testimony may be rebutted by testimony from other experts or by other evidence of facts.
There are often situations of overlap between these professional and expert witness roles.
The role of an expert witness should be to give an impartial and unbiased assessment or interpretation of the evidence.
Rule 702 held that proof that establishes scientific reliability of expert testimony must be produced before it can be admitted.
If a witness is relying primarily on experience to reach an opinion, then that witness must explain how that specific experience leads to that particular opinion.
The expert cannot just state his opinion, the expert has to justify it.
The expert should be aware of relevant court decisions that relate to the expert's role within their own jurisdiction.
The experts are being subjected to increasing scrutiny which have sometimes resulted in suspension or criticism.
This area of law will continue to evolve.
Statements and reports
Statements and reports
A statement in a criminal case is a report that has a standard wording.
The effect of this declaration is to render the individual liable for criminal prosecution if they have lied.
A statement may be agreed by both defence and prosecution, negating the need for court attendance.
A statement in official form or a sworn affidavit is commonly acceptable alone.
Attending court
Most courts now have some form of witness liaison units.
The court does have the power to compel attendance.
A witness summons is a court order signed by a judge or other court official that must be obeyed.
Evidence in court
The witness is liable for the penalties of perjury.
The examination in chief and the witness will be asked to confirm the truth of the facts in their statement(s).
During cross-examination, lawyers will have the opportunity to question the witness.
During re-examination, the original lawyer has the opportunity to clarify anything that has been raised in cross-examination.
The judge may ask questions at any time.
Healthcare professionals as witnesses in court
Any medicolegal report must be prepared and written with care.
The dress and demeanour should be compatible with the role of an authoritative professional.
The oath or affirmation should be taken in a clear voice that is loud enough to reach across the court room.
The witness should always answer the question posed.
A witness should also expect to have qualifications, experience and opinions challenged.
A witness must be alert to attempts by lawyers to circumscribe answers unreasonably.
Preparation of medicolegal reports
The diversity of uses of a report is reflected in the individuals or groups that may request one.
Release of medical records requires the consent of the patient and, if at all possible, this should be given in writing to the doctor.
There are exceptions, particularly where serious crime is involved.
It is considered inappropriate for non-judicial state agencies to order a doctor to provide confidential information.
Content of a statement or report
The basis of most reports and statements lies in the contemporaneous notes.
When instructed to prepare an expert report always clarify whether or not a specific structure is required.
A professional witness statement will be headed by specific legal wording.
Clarity and simplicity of expression make the whole process simpler.
The contemporaneous clinical notes may be required to support the statement.
An autopsy report is confidential and should only be disclosed to the legal authority who commissioned the examination.
Doctors must resist any attempt to change or delete any parts of their report by lawyers.
The ethics of medical practice
Introduction
Medical and healthcare practice has many forms and can embrace many backgrounds and disciplines.
Basis of medical ethics
The Greek tradition of medical practice was epitomised by the Hippocratic School on the island of Kos.
The Hippocratic Oath lay the foundation for what is broadly called ‘medical ethics'.
International codes of medical ethics
World Medical Association (WMA) aims to establish and promote the highest possible standards of ethical behaviour and care by physicians.
Duties of doctors and other healthcare professionals: UK perspective
The General Medical Council (GMC) in the UK issues publications on how a registered medical practitioner (a doctor) should undertake good medical practice.
The Health & Care Professions Council (HCPC) is a body created by statute in England & Wales, which regulates healthcare professionals.
Medical ethics in practice
The formal role of ethics in contemporary health and social care has become much more clearly defined.
The NHS Health Research Authority provides governance arrangements for research ethics committees.
Medical ethics as a subject is incorporated into medical school curricula.
There are very few medical or healthcare activities that do not have some ethical considerations.
Although the spectrum of unethical conduct is wide, certain universally relevant subjects are recognised.
Confidentiality
Confidentiality and consent are the two primary duties.
A number of permissible situations when confidentiality may not apply.
Personal data is information that relates to an identified or identifiable individual.
Disclosure of personal information
Disclosures should be the minimum necessary for the purpose and follow all relevant legal requirements.
Records should be kept of all decisions and actions.
Disclosures required by law
Certain government agencies or bodies may have statutory power to access patients' records.
Disclosing information with consent
Certain patients may wish to withhold particular aspects of personal information.
Clinical situations such as medical emergencies may mean that information is passed without consent.
Disclosure requiring express consent
Many important uses of patient information contribute to the overall delivery of health and social care.
Disclosure in the public interest
There may be a public interest in disclosing information.
It is always appropriate to seek advice in such circumstances.
Disclosures to protect the patient or others
Disclosure without consent may be justified when others are at risk of serious harm or death.
Disclosure concerning patients without the capacity to consent
It is expected that the doctor is seen to act in the patient's best interests.
Disclosure after death
A duty of confidentiality continues after a patient has died.
There may be situations when relevant information must be disclosed.
Consent
Treatment, investigation, or process must be freely given and not tainted by any degree of coercion or undue influence from others.
Patients with capacity to make decisions
Consent is a key concept of healthcare.
Previously the standard test to measure whether there has been a breach in their duty of care was known as the Bolam test.
In the UK the law on informed consent has changed following a Supreme Court judgement.
Doctors must now ensure that patients are aware of any material risks.
The test of materiality is whether, in the circumstances of the particular case, a reasonable person in the patient's position would be likely to attach significance to the risk, or the doctor is or should reasonably be aware that the particular patient would be likely to attach significance to it.
In some settings written consent is mandatory.
The responsibility for seeking consent is that of the doctor undertaking the investigation or treatment.
Such a duty can be delegated if the person to whom it is delegated is appropriately trained and has appropriate knowledge of the treatment or investigation proposed.
Young people, children and consent
Age is not necessarily a determining factor in the ability to consent.
However, it is generally accepted that those aged 16 years and older have the capacity to make decisions about treatment or care.
In the UK the GMC publishes guidance on making decisions.
Reference is made in England & Wales to Gillick competency and the Fraser guidelines.
Gillick competency and the Fraser guidelines refer to a legal case regarding contraception without parental consent.
This test of competence is utilised in a number of other jurisdictions.
Patients without capacity to make decisions
The doctor must engage with those who are close to the patient and with colleagues involved in the healthcare.
In England & Wales decisions about those who lack capacity is governed by the Mental Capacity Act 2005 (MCA).
The MCA is intended to protect and empower people who may lack the mental capacity to make their own decisions about their care and treatment.
It applies to people aged 16 and over.
It covers a range of decisions about everyday living and more serous potentially life-changing decisions.
The nature of capacity may vary dependent on the task.
The MCA assumed that every person has the capacity to make a decision themselves, unless it is proved otherwise.
The Act sets out a 2-stage test of capacity:
Does the person have an impairment of their mind or brain, whether as a result of an illness, or external factors such as alcohol or drug use?
Does the impairment mean the person is unable to make a specific decision when they need to?
Mental capacity can also fluctuate with time.
The determination of capacity is made by determining whether the person is able to understand, retain and evaluate the information, and communicate their decision.
Regulation of doctors and other professionals
The General Medical Council
In the UK, the regulatory body for registered medical practitioners (doctors) is the General Medical Council (GMC).
The GMC controls entry to the List of Registered Medical Practitioners (the medical register).
The GMC has legal powers designed to maintain the standards the public have a right to expect of doctors.
Before the GMC can stop or limit a doctor's right to practise medicine, it needs evidence of impaired fitness to practise.
Doctors (and other healthcare professionals) in the UK have a ‘professional duty of candour'.
Legal framework for GMC fitness to practise procedures
Procedures are divided into two separate stages: Investigation and Adjudication.
In the investigation stage cases are assessed to determine whether they need referral to the Medical Practitioners Tribunal Service (MPTS) for adjudication.
The adjudication stage consists of a hearing by a medical practitioner's tribunal.
The Fitness to Practise Panel hears evidence and decides whether a doctor's fitness to practise is impaired.
The GMC and appeal the MPTS's decision to the court.
Doctors have a right of appeal to the High Court.
Medicolegal aspects of death
Introduction
Definition of death
Death is not an event; it is a process in which cellular metabolic processes in different tissues and organs cease to function at different rates.
This differential rate of cellular death results in substantial debate – from ethical, cultural, religious and moral perspectives – as to when ‘death' actually occurs.
Cellular death
Cellular death implies the cessation of respiration (the utilisation of oxygen) and the normal metabolic activity in the body tissues and cells.
Cessation of respiration is soon followed by autolysis and decay, which, if it affects the whole body, is unchallengeable evidence of true death.
Skin and bone can remain metabolically active and thus ‘living' for many hours and their cells can be successfully cultured days after somatic death.
White blood cells are capable of movement for up to 12 hours after cardiac arrest.
The concept of microscopic identification of a vital reaction to injury of doubtful reliability.
The cortical neuron, on the other hand, dies after only 3–7 minutes of complete oxygen deprivation.
Somatic death and resuscitation
Somatic death means that the individual will never again communicate or deliberately interact with the environment.
The key element in this definition is ‘irreversible'.
There is no statutory definition of death in the United Kingdom.
Brain-stem death would eventually result in respiratory arrest causing myocardial hypoxia and cardiac arrest.
There is a spectrum of survival.
Prolonged disorders of consciousness
Disorders of consciousness (DOC) include: coma, vegetative state (VS), and minimally conscious state (MCS).
VS may be judged to be ‘permanent' 12 months after traumatic brain injury or 3 months after non-traumatic brain injury.
Human Rights Act 1998: the ‘right to life' and the right not to be subjected to inhuman and degrading treatment.
Legal permission from the Court of Protection is no longer needed to end life support for patients in a permanent VS.
Tissue and organ transplantation
There are very few countries where transplantation is expressly forbidden.
Few religions forbid it – Jehovah's Witnesses are one such group.
The Human Tissue Authority has issued guidance regarding the issues of consent for removal of organs for either research or transplantation under the Human Tissue Act where donors are deceased.
Homologous transplantation
Homologous transplantation is the process by which tissue is moved between sites on the same body.
Homologous blood transfusion can be used in certain situations.
Live donation
The most common example is blood transfusion.
The Transplantation Society adopted a consensus statement on the care of the live kidney donor.
This consensus statement addressed the responsibility of communities for living donors.
The care of the live kidney donor is often neglected in schemes where vulnerable individuals are exploited.
Cadaveric donation
Cadaveric donation is the major source of all tissues for transplantation.
The aim is to minimise the ‘warm ischaemic time'.
Developed countries have sophisticated laws to regulate it.
These laws vary greatly: opt-in vs opt-out systems.
Xenografts
Xenotransplantation is the transplantation of living cells, tissues or organs from one species to another.
Organs or tissue such as heart valves, corneas, hearts and kidneys have been explored for potential as xenografts.
Considerable difficulty with cross-matching the tissues.
Considerable concern about the possibility of transfer of animal viruses to an immunocompromised human host.
Cloning
Successful cloning of Dolly the sheep in 1996.
Much research is still to be done, with its attendant moral and ethical considerations.
Cause of death determination and certification
The degree of certainty with which the doctor is required to decide the cause of death may vary between jurisdictions.
The outcome would not have occurred ‘but for' the occurrence of the illness, disease or alleged action/omission of another person.
In general, if a doctor knows the cause of death, and that cause of death is natural (without any suspicious or unusual features), they may issue a medical certificate of cause of death (MCCD).
The format for certifying the cause of death was defined by the World Health Organisation (WHO) in 1979.
Part I is divided into subsections and generally three: (a), (b) and (c), are printed on the certificate.
Doctors should not record the mode of death in isolation.
If a mode is specified, it should be qualified by indicating the underlying pathological abnormality leading to that mode of death.
Medical Examiners, or Medical Reviewers are seniors who will scrutinise and confirm the cause of all deaths that do not need to be investigated by a coroner.
International Classification of Diseases (ICD) is the international ‘standard diagnostic tool for epidemiology, health management and clinical purposes'.
In some countries, doctors also have to record the manner of death (e.g., homicide, suicide).
Violence in society, medicolegal investigation of death and autopsy
Homicide and interpersonal violence
The United Nations Global Study on Homicide 2013 provides the most comprehensive, and most recent, international data on ‘intentional homicide'.
In 2012, there were 437,000 homicides, giving an average rate of 6.2 per 100,000 people.
There were marked regional and sub-regional variations.
The overall trend globally appears to be one of a decreasing homicide burden.
Global homicide data by age
Most victims were less than 44 years of age.
Global homicide data by gender
Males account for 79% of all homicide victims, and 95% of all perpetrators.
47% female homicide victims were killed by an intimate partner or family member.
Global intimate partner and domestic violence-related homicide
14% of all homicide victims were killed by an intimate partner or a family member, with a global rate of 0.9 per 100,000.
Female victims were consistently higher in this type of homicide.
79% of those homicide victims killed by intimate partners were women.
Female victims in this category of homicide were younger than other female homicide victims.
Homicide mechanism
Weapons played a significant role in homicide globally.
Alcohol consumption was highly associated with homicide.
Social trends and geopolitical change can often dramatically influence these factors.
Medicolegal investigation of death
The types of deaths that cannot be certified by a doctor are examined by a variety of legal officers across the world.
There is currently no legal duty for a doctor to report an unnatural death to the coroner.
A post mortem examination may now be limited to an external examination, or a ‘minimally invasive' radiological examination, or involve an internal examination.
The autopsy rate varies widely from jurisdiction to jurisdiction.
The autopsy
In general terms, autopsies are performed for two reasons: clinical clarification and medicolegal purposes.
The medicolegal autopsy is performed on behalf of the State.
Ideally, autopsies should be performed by a pathologist specifically trained to undertake such an examination.
The autopsy should be performed in a mortuary with adequate facilities.
Many autopsies will require ancillary investigations, such as radiological, toxicological, biochemical and microscopic analyses.
Virtual autopsy, or virtopsy, techniques play a significant role in reducing the requirement for a full autopsy examination.
The ‘Minnesota protocol'
The Minnesota Protocol on the Investigation of Potentially Unlawful Deaths aims to protect the right to life.
The protocol convers all stages of the pathological death investigation process.
Tissue sample should be retained in formalin for microscopic examination.
Exhumation
An examination of a body after exhumation is seldom as good as the examination of a fresh body.
In cases of possible poisoning, samples such as soil from above, below and to the sides of the coffin may be submitted for toxicology.
The appearance of the body after death
Introduction
Biochemical markers help to determine the time since death, or post-mortem interval (PMI).
The early post mortem interval
Rapid changes after death
With loss of neuronal activity, all nervous activity ceases, the reflexes are lost and breathing stops.
The retinal vessels, viewed with an ophthalmoscope, show the break-up or fragmentation of the columns of blood.
The eyes lose their intraocular tension.
The muscles become flaccid, but may retain their reactivity for some hours after cardiac arrest.
Discharges of the dying motor neurons may stimulate small groups of muscle cells and lead to focal twitching.
Cessation of circulation usually renders the skin, conjunctivae and mucous membranes pale.
The skin of the face and the lips may remain red or blue in colour in hypoxic/congestive deaths.
Neither hair nor nails grow after death.
Loss of muscle tone after death may result in voiding or urine and faeces.
Post mortem leakage of semen from the penile urethra may occur.
Regurgitation of gastric contents is common in terminal collapse and seen in a significant proportion of all autopsies.
Rigor mortis
Rigor mortis is a temperature-dependent physicochemical change that occurs within muscle cells as a result of lack of oxygen.
In the presence of low ATP and high acidity, the actin and myosin fibres bind together and form a gel.
The muscles become stiff but do not shorten unless they are under tension.
If muscle glycogen levels are low, or if the muscle cells are acidic at the time of death, the process of rigor will develop faster.
Electrocution, which causes repeated stimulation of the muscles, is also associated with rapidly developing rigor.
Rigor is generally first detectable in the smaller muscle groups.
On its own, rigor mortis has very little utility as a marker of the PMI because of the large number of factors that influence it.
In temperate conditions, rigor can commonly be detected
In the face between approximately 1 and 4 hours after death.
In the limbs between approximately 3 and 6 hours after death.
The strength of rigor increases to a maximum by approximately 18 hours after death.
Once established, rigor can remain for up to 2 days or so after death until autolysis and decomposition of muscle cells intervene and muscles become flaccid again.
It is best to test for rigor across a joint using very gentle pressure from one or two fingers only.
Re-establishment of rigor mortis can occur following mechanical loosening.
Cadaveric rigidity
Cadaveric rigidity is instantaneous post mortem onset of rigor mortis before the expected onset of rigor.
The majority of historical accounts do not stand up to critical scrutiny.
Post mortem hypostasis
The relaxation of the muscular tone of the vascular bed allows simple fluid movement to occur within the blood vessels.
There is also filling of the dependent blood vessels.
Under the influcence of gravity, red blood cells passively settle in the lowest areas of the body.
Post mortem hypostasis of lividity is referred to as the pink, purplish bluish colour change to these lowest areas.
Hypostasis is not always seen in a body and it may be absent in the young, the old and the clinically anaemic or in those who have died from severe blood loss.
It may be masked by those with darker skin tones and other conditions such as jaundice.
Post mortem hypostasis occurs where superficial blood vessels can be distended by blood.
Compression of skin in contact with a firm surface prevents such distension, and results in areas of relative or complete pallor within hypostasis.
It generally develops in the first 30 minutes after death and becomes very obvious up to about 12 hours after death.
The site and distribution of the hypostasis can be used to deduce the position of the body after death.
Areas of pallor around the mouth and the nose may also add to the inpression of suffocation.
Repositioning of the body after death may result in two overlapping patterns.
Cooling of the body after death
It cannot be viewed solely as a simple physical property of a warm object in a cooler environment.
Three basic forensic assumption must be made in order to use body temperature as an indicator of the time of death:
The body temperature was 37°C at the time of death.
The post mortem body temperature readings can be taken.
The body has lain in a thermally static environment.
Other post mortem changes
Decomposition/putrefaction
Decomposition results in liquefaction of the soft tissue over a period of time.
The process is first visible as an area of green discoloration of the right iliac fossa of the anterior abdominal wall.
The extension of the commensal gut bacteria through the bowel wall and into the skin, where they decompose haemoglobin, resulting in the green color.
The blood vessels provide an excellent channel through which the bacteria can spread.
The bacteria's passage is marked by the decomposition of the haemoglobin.
Marbling is linear branching patterns of variable discoloration of the skin when the bacteria pass through superficial vessels.
Blisters or large bullae containing red or brown putrefaction fluid or gas can form.
In temperate climate, gas formation is common in soft tissue, causing the body to swell.
The increased internal pressure causes the eyes and tongue to protrude and forces blood-stained fluid up from the lungs.
Insects and other animals may significantly accelerate the decomposition process.
Some organs, such as the prostate, the uterus and the tendons and ligaments, are relatively resistant to putrefaction.
Immersion and burial
Immersion in water or burial will slow the process of decomposition.
Casper's law: if all other factors are equal, then, when there is free access of air, a body decomposes twice as fast than if immersed in water and eight times faster than if buried in earth.
The most common position of a body in water is
Face down with the air-containing chest nearest the surface and
The head and limbs hanging dependently lower in the water.
The first change that affects the body in water is the loss of epidermis.
Exposure to water can, in some cases, predipose to the formation of adipocere.
Adipocere
Adipocere is a chemical change in the body fat, which is hydrolysed to a waxy substance with a texture similar to soap.
Thhe need for water means that this condition is most commonly seen in bodies found in wet conditions.
In the early stage of formation, adipocere is a pale, rancid, greasy semi-fluid material with a most unpleasant smell.
As the hydrolysis progresses, the material becomes more brittle and whiter.
When fullly formed, adipocere is a grey, firm, waxy compound that maintains the shape of the body.
Mummification
A body lying in dry condition may desiccate instead of putrefy.
Mummified tissue is dry and leathery and generally brown in color.
It generally occurs in the absence of bacterial or insect influence.
Mummification needs not affect the whole body.
Skeletalisation
The speed of skeletalisation depends on many factors.
There are a number of techniques for extracting DNA from bone.
There is no reliable means of accurately dating bones.
Post mortem injuries
Post mortem injuries do not actively bleed but many do leak blood, especially those on the scalp and in bodies recovered from water.
Post mortem injuries do not have a rim of an early inflammatory response in the wound edges.
However, the lack of this response does not exclude an injury inflicted in the last moments of life.
Estimation of the post mortem interval
None of the changes after death is capable of providing a precise marker of PMI.
The most reliable would appear to be related to the cooling of the body after death.
Body temperature
It is the core temperature which is relevant.
The most widely recognised means of estimating the time of death with temperature is Henssge's nomogram.
Henssge's nomogram relies on three measurements - body temperature, ambient temperature and body weight.
Other techniques used in estimating or corroborating PMI
Forensic entomologists can determine a probable time of death from examination of the insects that invade a body.
Analysis of gastric content may assist in an investigation.
Death from natural causes
Introduction
The WHO's definition of a sudden death is death within 24 hours of the onset of symptoms.
A sudden death is not equivalent to en unexpected death.
Cardiovascular system
Coronary artery disease
Bleeding may occur into a plaque, and be seen as sub-intimal haemorrhage at autopsy.
The compromised area of myocardium may rupture between 3 days and 1 week after the clinical onset of the infarction.
SCD is defined as the unexpected death without an obvious noncardiac cause that occurs:
within 1 hour of witnessed symptom onset (established SCD).
within 24 hours of unwitnessed symptom onset (probable SCD).
Dysfunctions of the cardiac conduction and autonomic nervous systems are known to contribute to SCD pathogenesis.
Hypertensive heart disease
Long-standing hypertension can result in cardiac remodeling.
While exercise and hypertension can both be associated with development of LVH,
The cardiac remodeling from hypertension is pathological with associated fibrosis and risk of heart failure and mortality.
LVH in athletes in generally non-pathological and lacks the fibrosis.
Aortic stenosis
Aortic stenosis is seen:
in the elder with calcified aortic valves.
in youngesters who have a congenital bicuspic aortic valve.
Angina, exertional syncope and heart failure are key symptoms indicating a need for intervention.
Senile myocardial degeneration
The senile heart is small.
The surface vessels are tortuous.
The myocardium is soft and brown owing to accumulated lipofuscin in the cells.
Primary myocardial disease
Molecular investigations must be key elements in the post mortem investigation of SCDs with a structurally normal heart.
Atheromatous aneurysm of the aorta
The aneurysms may be saccular or fusiform.
The wall of the aneurysm is commonly calcified and the lumen is commonly lined by old laminated thrombus.
Dissecting aneurysm of the aorta
Dissecting aneurysms are principally found in individuals with hypertension, but may also be seen in younger individuals with connective tissue defects.
Syphilitic aneurysms
Treponema pallidum invades the aortic wall.
The inflammatory response progresses towards obliterative endarteritis and necrosis of the muscular and elastic fibres in the aortic media.
Ruptured berry (sacullar) aneurysm
A relatively common cause of sudden collapse and rapid death.
The precise mechanism of sudden death following subarachnoid hemorrhage is not understood.
Cerebral hemorrhage, thrombosis and infarction
Spontaneous intracerebral hemorrhage is most often found in the external capsule/basal ganglia.
It arises from rupture of a micro-aneurysm of the lenticulo-striate artery, or Charcot-Bouchard aneurysm.
Respiratory system
Saddle emboli can resut in massive acute right-heart strain and failure.
Smaller thromboemboli become lodged in smaller-calibre pulmonary blood vessels where they can interfere with pulmonary function and lead to myocardial ischaemia and cardiac arrest.
Establishing the causal relationship between the embolism and an injurious event is difficult.
Gynaecological conditions
A complication of pregnancy is most likely the cause of death in a deceased pregnant woman.
Maternal death can be classified into ‘direct' deaths, ‘indirect' deaths or ‘coincidental' deaths.
Deaths from asthma and epilepsy
Deaths in people with asthma may relate substantially to co-morbidities.
Visual autopsy findings include hyper-inflated lungs and plugging of the airways by tenacious and viscous mucus.
Microscopy of the lungs commonly reveals chronic airway remodelling, with basement membrane thickening, goblet cell and smooth muscle hyperplasia, and super-imposed airway inflammation with eosinophils.
Epilepsy is a condition where a person has recurrent seizures.
Secondary or symptomatic epilepsy can be caused by head injuries, toxic chemicals or drugs of abuse, alcohol or benzodiazepine withdrawal and stroke.
Sudden unexpected death in epilepsy (SUDEP) may be related to seizure-induced arrhythmia, seizure-mediated inhibition of respiratory centers or a complication of anti-epileptic treatment.
Post mortem findings in SUDEP are non-specific.
Deaths and injury in infancy
Introduction
Specific features of injuries to infants and children require their own consideration.
Stillbirths
The causes of many stillbirths remain unknown, but may include maternal infections in pregnancy, maternal disorders, intrauterine infections, birth trauma or congenital abnormalities.
If death occurs more than a couple of days before birth
The fetus is commonly macerated.
The skin is discolored, usually a pinkish-brown or red, with extensive desquamation of the skin.
The tissue has a soft and slimy transluence.
There may be partial collapse of the head with overriding of the skull plates.
A ‘stillbirth certificate' can be completed either by a doctor or a midwife.
Infanticide
Infanticide is the act where a mother kills her child during its first year of life.
Infanticide is a less serious charge than murder and does not result in the mandatory penalty of life imprisonment.
There is a legal presumption that all deceased babies are stillborn and so the onus is on the prosecution.
The viability or otherwise of a baby at the momenet of complete expulsion is not easy to determine.
Proof of a live birth must show that the infant breathed or other signs of life such as movement or pulsation of the umbilical cord.
The lung floatation test was reliable in 98% of cases.
Not a single false-positive result where the lungs of a stillborn individual floated.
There are cases of false-negative result where a live born child's lungs did not float.
Lungs that don't float cannot be taken as a proof that a newborn never breathed at all.
Common feature of lungs from stillbirths
Lungs are firm and no crepitation when squeezed.
Microscopy shows partial expansion of terminal air spaces as a consequence of hypoxia-induced inspiratory efforts.
Some other indicators of life:
Confirmed milk in the stomach.
The umbilical cord is shrivelled or shows an inflammatory ring of impending separation.
The estimation of maturity of a newborn baby or fetus
A rough estimate of gestational age may be provided by Haase' Formula.
In living newborn infants, the New Ballard Score can be used to determine gestational age through neuromuscular and physical assessment.
Unexplained deaths in infancy
Unexplained infant deaths include sudden infant deaths and unascertained deaths.
‘Back to Sleep' campaign, refraining from smoking during pregnancy, and avoiding overheating babies have substaintially reduced unexplained infant deaths.
Sudden infant deaths syndrome (SIDS): the sudden death of an infant less than 1 year of age that remains unexplained after a complete autopsy and death scene investigation.
In about 70% of SIDS cases, the autopsy reveals intrathoracic petechiae on the pleura, epicardium and thymus.
Child abuse
Child abuse is a generic term that includes all forms of physical and emotional ill-treatment.
The Battered Child Syndrome describes harm from inflicted injury mechanisms
Epidemiology
The most common issues of contention are distinction between accident and abuse, or non-accidental injury (NAI).
Post mortem in children
Full radiological skeletal surveys precede the physical examination of the body.
The procedure is adapted to take account of development-specific differences between children and adults.
Bruising
The features of bruises that are important can be summed up as site, age and pattern.
Bruises over soft tissue areas in non-mobile infants, bruises that carry an imprint of an implement and multiple bruises of uniform shape are suggestive of some forms of physical abuse.
Skeletal injury
Imaging recommended for different age groups:
Skeletal survey in children under two years of age.
Skeletal survey and CT head scan in children under one year.
Rib fractures is a feature of the application of substantial force and are rarely accidental in children.
One particular pattern is areas of callus on the posterior ribs, often lying in a line adjacent to the vertebrae, and giving a string-of-beads appearance.
Abusive skull fractures are more likely to be multiple, comminuted, bilateral and cross sutures.
A head-first fall from 0.9 m onto a concrete surface had a high likelihood of fracture.
Head injuries
Head injuries are the most frequent cause of death in child abuse.
In the past, the diagnosis of shaken baby syndrome (SBS) depended on the triad of subdural hemorrhage, retinal hemorrhage and encephalopathy.
It is now generally agreed that the finding of the ‘triad' alone should not lead to an automatic assumption of NAI.
Abusive Head Trauma (AHT) and Inflicted Head Injury (IHI) have gained wider appeal.
Each case must be considered in its own context before conclusions are reached.
Occular injuries
All children suspected of being physically abused should have their eyes examined by an ophthalmologist.
Possible occular findings in AHT:
Cherry hemorrhage: isolated and elevated circular bleeds, typically in the equatorial retina.
Perimacular ridges: elevated and circular retinal folds with a canopy of internal limiting membrane (ILM).
Survivors had optic nerve atrophy and macular ganglion cell loss.
Oral injuries
The current evidence indicates that a child with a torn frenum should undergo a full child protection evaluation.
Visceral injuries
Visceral injuries are the second most common cause of death.
Splenic injuries are rare in physical child abuse.
Other injuries
Other injuries in physical child abuse include burns and human bites.
Human bites are common in child abuse and can be multiple.
Accidental injury in children occurs far more often than acts of physical child abuse.
Child sexual abuse
Child sexual abuse is divided into contact and non-contact abuse.
Assessment, classification and documentation of injury
Terminology of injury
A laceration is a split or tear in the skin caused by blunt impact.
Each jurisdiction will have its own specific legal classification of injury or wounding.
Murder and manslaughter are two of the offences that constitute homicide.
Manslaughter can be commited in one of three ways:
Killing with the intent for murder but where a partial defence applies.
Gross negligence manslaughter: conduct that was grossly negligent given the risk of death, and did kill.
Unlawful and dangerous act manslaughter: conduct taking the form of an unlawful act involving a danger of some harm, that resulted in death.
The term involuntary manslaughter is commonly used to describe a manslaughter falling within (2) and (3) while (1) is referred to as voluntary manslaughter.
A wound is an injury that breaks the continuity of the skin.
The crime of murder is committed where a person of sound mind and discretion unlawfully kills with intent to kill or cause grievous bodily harm (GBH).
Non-fatal violence-related injury
How does the body respond to injury?
Damaged or dead cells express molecules that are recognized by the immune system: damage-associated molecular patterns (DAMP) and alarmins.
An efficient and effective coordinated localized resopnse leads to resolution of the inflammatory environment, healing/repair of damaged tissue, and restoration of normal function.
These processes assist in the microscopic ageing of injury.
The following factors may all influence whether the trauma sustained is likely to have a fatal outcome:
The trauma load: the nature and severity of the injury(s).
The mechanism of injury.
The rapidity with which emergency medical care is provided, and the availability of modern trauma care/intensive care facilities.
The age and health status of the injured person.
The body's physiological response to injury.
The physiological response to injury is not only complicated but complex, and the behavior of the response is non-linear.
Types of injury
Injury caused by the application of physical force can be divided into two main groups: blunt force and sharp force.
Other means include ballistic, thermal, chemical, and electrical injury.
Blunt force injury
The nature of the force applied may include direct blows (impacts), traction, torsion and oblique or shearing forces.
Blunt force trauma may have a number of outcomes: no injury, tenderness, pain, reddening (erythema), swelling (oedema), bruising (contusion), abrasions (grazes), lacerations, and fractures.
Bruises
Bruises are caused by leakage of blood from damaged blood vessels, often small-diameter vessels.
Bruises can also occur in the deeper tissues.
Bruises evolve and can ‘migrate'.
In superficial bruises, the leakage of blood is confined to the the epidermis or the upper strata of the dermis.
Intradermal bruises are often associated with diffuse compression forces.
The distribution (pattern) of a number of bruises can help corroborate the nature of the causative force.
In clinical practice, typical appearance is rarely seen.
Age estimation based on the colour of bruising is not now considered appropriate.
The appearance of yellow is indicative of early healing change in the injury occurring over a timeframe of some hours.
Yellow discolouration in a bruise does not appear before 18 hours after the blunt contact.
Bruises known to be older than 18 hours may be associated with no yellow discolouration.