Sudden bleeding into brain tissue is common, usu- ally in old age and in those with significant hyper- tension and, together with cerebral thrombosis and
resulting brain infarction, is the commonest cause of the well-recognized cluster of neurological signs colloquially termed a ‘stroke’.
The term cerebrovascular accident (CVA) is in common usage in such circumstances, both as a clinical diagnosis and as a cause of death. Occa- sionally, it is misinterpreted by the public, and sometimes also by legal officials, as indicating an unnatural cause of death because of the use of the word ‘accident’. To avoid this small risk, it is much more satisfactory, if the exact cause is known, to use the specific term that describes the aetiology (cerebral haemorrhage or cerebral infarction) or, if the aetiology is not known, to use the generic term cerebrovascular lesion (Figure 6.7).
Spontaneous intracerebral haemorrhage is most often found in the external capsule/basal ganglia of one cranial hemisphere and arises from rupture of a micro-aneurysm of the lenticulo-striate artery, sometimes called a Charcot–Bouchard aneurysm.
The sudden expansion of a haematoma compresses the internal capsule and may destroy some of it, leading to a hemiplegia (Figure 6.8).
Death in such circumstances is not usually sudden, although there is a complex interaction between the brain and the heart, and thus a ‘stroke’
affecting a region of the brain important in such control can precipitate a cardiac arrest.
■ Respiratory system
The major cause of sudden death within the respiratory organs is again vascular. Pulmo- nary embolism is very common and is the most
Figure 6.7 Acute cerebral infarction (predominantly middle cerebral artery territory).
Respirator y system
clinically under-diagnosed cause of death. In almost every case, the source of the emboli is in the deep leg or pelvic veins (Figure 6.9). Tis- sue trauma, especially where it is associated with immobility or bed rest, is a very common predisposing factor in the development of deep vein thrombosis. Most thromboses remain silent and cause no problems, but a proportion embol- ize and block pulmonary arteries of varying size.
Large thromboemboli can occlude the origin of the pulmonary arteries (saddle emboli), resulting in massive acute right-heart strain and failure as a result of mechanical blockage, whereas smaller thromboemboli become lodged in smaller-calibre pulmonary blood vessels where they interfere with pulmonary function and lead to myocardial ischaemia and cardiac arrest.
A predisposing cause for pulmonary thrombo- embolism can be identified in a significant propor- tion of such deaths, including immobility following surgery or trauma, use of the oral contraceptive, smoking or where there is a history of metastatic cancer or a blood clotting abnormality. However,
the remainder occur unexpectedly in normal, ambulant people who have reported no clinical symptoms. This sometimes makes establishing the causal relationship between death and an injuri- ous event difficult. For the purposes of civil law (where the standard of proof for causation is ‘on the balance of probabilities’) the embolism can often be linked to the trauma, but in a criminal trial in which a higher standard of proof (‘beyond reasonable doubt’) is required, it may be much harder to demonstrate a causal link between the two events.
Other rare causes of sudden death in the respi- ratory system (excluding bronchial asthma which is covered separately below) include massive haemo- ptysis from cavitating pulmonary tuberculosis or from an invasive tumour (Figure 6.10). Rapid (but
Figure 6.8 Recent intracerebral haemorrhage in a hypertensive individual.
(a)
Figure 6.9 Fatal pulmonary thromboembolism. Macroscopic (a) and microscopic (b) appearance.
(b)
6 Unexpe cte d and sudden death fr om natur al cause s
not sudden) deaths can also occur from fulminat- ing chest infections, especially virulent forms of influenza.
■ Gastrointestinal system
The main causes of sudden death in the gastrointes- tinal system are predominantly vascular in nature;
severe bleeding from a gastric or duodenal peptic ulcer can be fatal in a short time, although less tor- rential bleeding may be amenable to emergency medical/surgical intervention (Figure 6.11).
Mesenteric thrombosis and embolism, usually related to aortic or more generalized atherosclerosis, may result in infarction of the gut; a rapid but not sud- den death is expected if the infarction remains un -
diagnosed. Intestinal infarction owing to a strangulated hernia, or obstruction owing to torsion of the bowel as a consequence of adhesions can also prove rapidly fatal (Figure 6.12).
Peritonitis, following perforation of a peptic ulcer, diverticulitis or perforation at the site of a colonic tumour for example, can be rapidly fatal if not treated (Figure 6.13).
Many of these conditions present as sudden death in elderly people because they cannot, or will not, seek medical assistance at the onset of the symptoms, and are then unable to do so as their condition worsens.
■ Gynaecological conditions
When a female of childbearing age is found deceased, a complication of pregnancy must be considered to be the most likely cause of death until
Figure 6.10 Disseminated pulmonary tuberculosis (TB). Note also the cavitating (secondary TB) lesion.
Figure 6.11 Massive haemorrhage from erosion of blood vessels in the base of this peptic gastric ulcer.
Figure 6.12 Intestinal infarction following volvulus of the sigmoid colon.
Figure 6.13 Peritonitis. Note the fi brinous deposits on the surface of loops of intestines.
D eaths from asthma and epilepsy
other causes have been excluded. Abortion remains one possibility anywhere in the world, but espe- cially in countries where illegal abortion is still very common.
A ruptured ectopic pregnancy, usually in a Fal- lopian tube, is another grave obstetric emergency that can end in death from intraperitoneal bleed- ing unless rapidly treated by surgical intervention (Figure 6.14).
Maternal deaths (occurring during pregnancy or within 12 months of parturition in the UK) can be classified into ‘direct’ deaths (caused by diseases specifically related to pregnancy, such as pulmo- nary thromboembolism, pre-eclampsia, obstetric haemorrhage, amniotic fluid embolism, acute fatty liver of pregnancy or ectopic gestation), ‘indirect’
deaths (from pre-existing disease exacerbated by pregnancy such as congenital heart disease or a cardiomyopathy) or ‘coincidental’ deaths. Maternal deaths are the subject of anonymous review in the UK as part of an ongoing ‘Confidential Enquiry’.
■ Deaths from asthma and epilepsy
Deaths from acute bronchial asthma are infrequent with increasingly effective pharmacological control of this chronic condition. Asthma ‘attacks’ may be triggered by a number of common and household allergens, as well as commonly abused drugs such as heroin and crack cocaine (particularly when it is
smoked). The ‘naked eye’ autopsy findings include hyper-inflated lungs and mucus plugging of the air- ways by tenacious, 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 (Figure 6.15).
An anaphylactic component may be responsible for a fatal outcome, and post- mortem blood sampling for mast cell tryptase is often rewarding.
Epilepsy – recurrent unprovoked seizures – is associated with an increased risk of mortality and, while there may be specific reasons why a person with epilepsy may die (e.g. drowning as a result of a seizure while swimming), there are approxi- mately 500 sudden and unexpected deaths in epileptics each year in the UK where the precise cause of death is not identified. Such deaths have been classified as Sudden Unexpected Deaths in
Figure 6.14 Ectopic pregnancy leading to rupture of the Fallopian tube and massive intra-abdominal haemorrhage.
(a)
Figure 6.15 Bronchial asthma. (a,b) Microscopy demonstrating airway ‘remodelling’, mucus distension and infl ammatory cell infi ltration, including neutrophils and eosinophils.
(b)
6 Unexpe cte d and sudden death fr om natur al cause s
Epilepsy (SUDEP), defined as a ‘sudden unexpected, witnessed or unwitnessed, non-traumatic and non-drowning death in epilepsy, with or without evidence of a seizure, and excluding documented status epilepticus, where post-mortem examination does not reveal a toxicological or anatomic cause of death’.
The mechanism of death in such cases is uncer- tain, but may be related to a seizure-induced arrhythmia, seizure-mediated inhibition of respi- ratory centres or a complication of anti-epileptic treatment. Post-mortem findings in SUDEP are non- specific (for example pulmonary oedema and con- gestion) and the utility of the presence of a tongue injury in diagnosing a seizure is controversial.
Neuropathological examination of the brain is important in order to exclude the presence of a lesion capable of providing an explanation for seizure activity, such as, for example, an old brain injury or arteriovenous malformation, although the presence of more subtle changes in the brain, thought to represent evidence of seizure activity, cannot be taken as evidence of seizure activity at the time of death.
■ Further information sources
Arbustini E, Dal Bello B, Morbini P et al. Plaque erosion is a major substrate for coronary thrombosis in acute myocardial infarction. Heart 1999; 82: 269–72.
Fornes P, Lecompte D, Nicholas G. Sudden out-of-hospital coronary death in patients with no cardiac history. An analysis of 221 patients studied at autopsy. J Forensic Sciences 1993; 38: 1084–91.
Friedman M, Manwaring JH, Rosenman RH et al.
Instantaneous and sudden deaths. Clinical and pathological differentiation in coronary artery disease.
Journal of the American Medical Association 1973;225:
1319–28.
Hill SF, Sheppard MN. Non-atherosclerotic coronary artery disease associated with sudden cardiac death. Heart 2010;96: 1084–5.
Hinkle LE Jr, Thaler HT. Clinical classifi cation of cardiac deaths.
Circulation 1982; 65: 457–64.
Leadbeatter S. Extracranial vertebral artery injury – evolution of a pathological illusion? Forensic Science International1994;67: 33–40.
Libby P. Current concepts of the pathogenesis of the acute coronary syndromes. Circulation 2001; 104:
365–72.
Millward-Sadler GH. Pathology of maternal deaths. In:
Kirkham N, Shepherd N (eds). Progress in Pathology 2003, Vol 6. London: Greenwich Medical Media, 2003;
163–85.
Nashef L. Sudden unexpected death in epilepsy: terminology and defi nitions. Epilepsia 1997; 38(Suppl 11): S6–8.
Sidebotham HJ, Roche WR. Asthma deaths; persistent and preventable mortality. Histopathology 2003; 43:
105–17.
Soilleux EJ, Burke MM. Pathology and investigation of potentially hereditary sudden cardiac death syndromes in structurally normal hearts. Diagnostic Histopathology 2008;15: 1–26.
Tomson T, Nashef L, Ryvlin P. Sudden unexpected death in epilepsy: Current knowledge and future directions. Lancet Neurol200811: 1021–31.
■ Introduction
■ Stillbirths
■ Infanticide
■ The estimation of maturity of a newborn baby or fetus
■ Sudden infant death syndrome
■ Child abuse
■ Further information sources
Chapter
7
Deaths and injury in
infancy
■ Introduction
The outcomes of disease and trauma are, in general terms, the same in individuals of all ages, but there are some special features of injuries to infants and children that require specific consideration. Some relate to the law, and some to medical and patho- logical factors. Newborns, infants, toddlers, younger children and adolescents have their own unique problems, such as stillbirth and sudden infant death syndrome, which are different from those of fully developed adults. They are also dependent, vul- nerable and may encounter abuse, whether emo- tional, physical or sexual. This chapter emphasizes the pathologically relevant issues while Chapter 13 focuses more on the issues of the living.
■ Stillbirths
A significant number of pregnancies that continue into the third trimester fail to deliver a live child and result in a stillbirth. The definitions of a stillbirth vary from country to country, but the definition in England and Wales, which is perhaps typical, is that the child
must be of more than 24 weeks’ gestational age and, after being completely expelled from the mother, did not breathe or show any signs of life (Births and Deaths Registration Act 1953, as amended by the Still-Birth [Definition] Act 1992). These ‘signs of life’, in addition to respiration and heartbeat, are taken to mean movement, crying or pulsation of the umbilical cord.
If death occurs more than a couple of days before birth, the fetus is commonly macerated because of the effects of early decomposition combined with exposure to fluid (Figure 7.1). The infant is discoloured, usually a pinkish-brown or red, with extensive desquamation of the skin; the tissues have a soft, slimy translucence and there may be partial collapse of the head with over- riding of the skull plates. The appearance of the child is quite different from that seen in an infant that has died following a live birth and then begun to putrefy. Because many, if not most, of these deaths occur after the onset of labour and during the process of birth itself, no evidence of macera- tion will be present.
In England and Wales a child does not have a legally-recognized ‘separate existence’ (and thus
7 D eaths and injury in infancy
does not become a legal person, capable of acquir- ing legal rights such as inheritance and title) until he or she is completely free from the mother’s body, although the cord and placenta may still be within the mother.
The Infant Life (Preservation) Act 1929 made it an offence to destroy a baby during birth; how- ever, an exception was made in the Act for doc- tors acting ‘in good faith’ who, to save the life of the mother, have to destroy a baby that becomes impacted in the pelvis during birth.
As babies that are stillborn have never ‘lived’ in the legal sense, they cannot ‘die’ and so a death certificate cannot be issued. In England and Wales, a special ‘stillbirth certificate’ may be completed either by a doctor or a midwife if either was present at the birth or by either one of them if they have examined the body of the child after birth.
The causes of stillbirth are varied and may be undeterminable, even after a full autopsy. Indeed, it may be impossible to determine on the patho- logical features alone if the death occurred before, during or after birth. Recognized conditions lead- ing to intrauterine or peri-mortem death include prematurity, fetal hypoxia, placental insufficiency,
intrauterine infections (viral, bacterial or fungal), congenital defects (especially in the cardiovascular or nervous system) and birth trauma.
■ Infanticide
The term infanticide has a very specific meaning in the many countries that have introduced legisla- tion designed to circumvent the criminal charge of murder when a mother kills her child during its first year of life. In England and Wales, Section 1 of the Infanticide Act 1938 states that:
Where a woman by any wilful act or omis- sion causes the death of her child … under the age of twelve months, but at the time … the balance of her mind was disturbed by rea- son of her not having fully recovered from the effect of giving birth to the child or by reason of the effect of lactation consequent upon the birth of the child, then … she shall be guilty of … infanticide, and may … be dealt with and punished as if she had been guilty of the offence of manslaughter of the child.
Because manslaughter is a less serious charge than murder and does not result in the mandatory penalty of life imprisonment that is attached to murder, a verdict of infanticide allows the court to make an appropriate sentence for the mother, which is more likely to be probation and psychi- atric supervision than custody. The Infanticide Act indicates that the law recognizes the special nature of infanticide.
In England and Wales, there is a legal presump- tion that all deceased babies are stillborn and so the onus is on the prosecution, and hence the pathologist, to prove that the child was born alive and had a separate existence. In order to do this, it must be shown that the infant breathed or showed other signs of life, such as movement or pulsation of the umbilical cord, after having been completely expelled from the mother.
In the absence of eyewitness accounts, patho- logists can make no comment about the viability or otherwise of a baby at the moment of complete expulsion from the mother; one way that they may be able to comment on the possibility of separate existence is if they can establish that the child had breathed. However, establishing that breathing had taken place is still not absolute evidence of a
Figure 7.1 Maceration following intrauterine death. Note the widespread skin slippage and the umbilical cord around the neck.
Infantic ide
‘separate existence’, as a baby in a vertex delivery can breathe after the head and thorax have been delivered but before delivery of the lower body.
The ‘flotation test’, which used to be the defini- tive test for breathing, and hence separate existence, and which was depended upon for many centuries, is now considered to be unreliable, although it still appears in some textbooks. All that can be said with regard to flotation of the lungs is that if a lung or piece of lung sinks in water, the baby had not breathed sufficiently to expand that lung and so the child may have been stillborn. The converse is definitely not true, as the lungs of babies who are proven to have been stillborn sometimes float. This test is useless in differentiating between live-born and stillborn infants and should no longer be used (Figure 7.2).
To complicate matters further, many dead new- born babies are hidden shortly after birth and may not be discovered until decomposition has begun, which precludes any reliable assessment of the state of expansion of the lungs. Even with fresh bodies, the problems are immense and any attempt at mouth-to-mouth resuscitation or even chest com- pression will prevent any reliable opinion being given on the possibility of spontaneous breathing.
Conversely, if there is milk in the stomach or if the umbilical cord remnant is shrivelled or shows an inflammatory ring of impending separation, the child must have lived for some time after birth.
Establishing the identity of the infant and the identity of the mother is often a matter of great dif- ficulty, as these babies are often found hidden or abandoned (Figure 7.3). When the baby is found in the home, there is seldom any dispute about who the mother is. DNA may be used to confirm identity and parentage.
In those cases where the mother is traced, further legal action depends on whether the patho logist can definitely decide if the baby was born alive or was stillborn. If live-born, no charge of infanticide can be brought in English law unless a wilful act of omission or commission can be proved to have caused the death. Omission means the deliberate failure to provide the normal care at birth, such as tying and cutting the cord, clearing the air pas- sages of mucus and keeping the baby warm and fed. The wilful or deliberate withholding of these acts, as opposed to simple ignorance and inexperi- ence, is hard to prove. Acts of commission are more straightforward for the doctor to demonstrate as
(b) (a)
Figure 7.2 (a) Thoracic organs from a stillbirth. The lungs are fi rm and heavy with no crepitation when squeezed. (b) Microscopy of lungs from stillbirths showing partial expansion of terminal air spaces as a consequence of hypoxia-induced inspiratory efforts. Note also meconium aspiration.
Figure 7.3 Newborn infant disposal with decompositional/
putrefactive skin changes.
7 D eaths and injury in infancy
they may include a range of trauma, including head injuries, stabbing, drowning and strangulation.
The maturity of the infant is rarely an issue as most infants found dead after birth are at or near full term of 38–40 weeks. The legal age of matu- rity in Britain is now 24 weeks, although medical advances have allowed fetuses of only 20 weeks or less gestation to survive in specialist neo natal units.
In infanticide, the maturity is not legally material as it is the deliberate killing of any baby that has attained a separate existence, and this does not depend directly upon the gestational age.
■ The estimation of maturity of a newborn baby or fetus
Legal requirements may need an estimation of ges- tational age of the body of a baby or fetus in relation to an abortion, stillbirth or alleged infanticide. The following are considered ‘rule of thumb’ formulae for estimating maturity (and should be considered to provide very rough estimates):
1 Up to the twentieth week, the length of the fetus in centimetres is the square of the age in months (Haase’s rule);
2 After the twentieth week, the length of the fetus in centimetres equals five times the age in months.
There is considerable variation in any of the meas- ured parameters owing to sex, race, nutrition and individual variation, but it is considered possible to form a reasonable estimate of the maturity of a fetus by using the brief notes in Box 7.1.
Development can also be assessed using the femur length, ossification centres and the histo- logical appearances of the major organs. It may be necessary to seek expert advice, from radiologists and forensic anthropologists, when determining gestational age.
■ Sudden infant death syndrome
The incidence of sudden infant death syndrome (SIDS) – also known as ‘cot death’ or ‘crib death’ – has declined in many developed countries from approxi- mately 2 to 0.5 per 1000 live births, and was 0.28 per 1000 live births in England and Wales in 2007.
This decline has coincided with social and housing improvements as well as a worldwide ‘Back to Sleep’
campaign in the early 1990s, which encouraged mothers to place babies on their back to sleep rather than face down or on their side. Publicity campaigns have also advised mothers to refrain from smoking during pregnancy or near to their babies after birth and to avoid overheating babies by wrapping them up too closely. However, despite this significant decline, SIDS still forms the most common cause of death in the post-perinatal period in countries with a relatively low infant mortality rate.
SIDS has been defined as ‘the sudden unex- pected death of an infant <1 year of age, with onset of the fatal episode apparently occurring during sleep, that remains unexplained after a thorough investigation, including the performance of a com- plete autopsy and a review of the circumstances of death and the clinical history’. The following are the main features of the syndrome.
■ Most deaths take place between 1 month and 6 months, with a peak at 2 months.
■ There is little sex difference, although there is a slight preponderance of males similar to that seen in many types of death.
■ The incidence is markedly greater in multiple births, whether identical or not. This can be partly explained by the greater incidence of pre- mature and low birth-weight infants in multiple births.
■ There is a marked seasonal variation in temper- ate zones: SIDS is far more common in the colder and wetter months, in both the northern and southern hemispheres.
Box 7.1 Estimation of fetal maturity
● 4 weeks – 1.25 cm, showing limb buds, enveloped in villous chorion
● 12 weeks – 9 cm long, nails formed on digits, placenta well formed lanugo all over body
● 20 weeks – 18–25 cm, weight 350–450 g, hair on head
● 24 weeks – 30 cm crown–heel, vernix on skin
● 28 weeks – 35 cm crown–heel, 25 cm crown–rump, weight 900–1400 g
● 32 weeks – 40 cm crown–heel, weight 1500–2000 g
● 36 weeks – 45 cm crown–heel, weight 2200 g
● 40 weeks (full term) – 48–52 cm crown–heel, 28–32 cm crown – rump, 33–38 cm head circumference, lanugo now absent or present only over shoulders, head hair up to 2–3 cm long, testes palpable in scrotum/vulval labia close the vaginal opening, dark meconium in large intestine