15.12.1 Sudden Death In Children: Sudden Infant Death Syndrome Flashcards
Define sudden infant death syndrome
- sudden and unexpected death of a baby
- occurring between birth and 2 years (reaching a maximum between 1 month and 1 year)
- Babies are clinically healthy before death with (at worst) only a minor symptom like mild upper respiratory tract or gastrointestinal tract infection
- diagnosis is one of exclusion
- No certain cause of death can be found even by means of a thorough death scene investigation, autopsy and laboratory examinations.
Sudden infant death syndrome according to:
Inquests Act (Act 58 of 1959)
Births and Deaths Registration Act (Act 51 of 1992)
- Unnatural death
- Autopsy mandatory
- Results to be reported to inquest magistrate
Epidemiology odd SIDS
- Insidence of SIDS in the age group one month to one year:
- Britain, USA, Europe: 50% of all deaths in this age group
- USA – 0,6/1000 live births
- Britain – 3/1000 live births
- Tygerberg: 2000 - 34/186 18% !!!!!
Risk factors for SIDS
- Age
- Sex
- Twins
- Seasonal variation
- Social status
Maternal:
- Smoking and drug abuse
- Anemia
- Urinary tract infection / VD
- Multiple pregnancies
- Previous prematurity
- Stilbirth
- Miscarraige
- Mother <20 years
- Poor clinic attendance
Baby:
- Prematurity
- Low birth weight
- Poor Apgar score
- Long stay in hospital
- Poor clinic attendance
- Poor weight gain
- Babies that are not breastfed
History of SIDS
- Previously healthy – mild URTI or GE.
- Laid down in cot in evening – found dead in morning.
- Sometimes found dead after morning feed.
- Hx sometimes suggestive of child sleeping with parents.
Scene SIDS
- Info mostly not available
- Pink froth at nose (sometimes)
- No petechial hemmorhages in eyes / face
- Higher incidence with babies sleeping on stomach
- ! Careful of hypostasis – mouth and neck
Autopsy
External examination – non-specific
NAIS (NOBS) HAS to be excluded
- Good history
- Thorough external examination
- Whole body X-rays if NAIS suspected (NO compromise)
- Look for petechial hemmorhages in eyes / face
- Try to attend scene
- Measurements
Internal examination – non-specific
- Intra-thoracic petechial hemorrhages (50%)
➡️Lungs – visceral pleura
➡️Heart – posterior epicardium
➡️Thymus – cortex
- Mild “respiratory infection” of mucosa of trachea and larynx (50%)
- Pulmonary congestion and edema
- Areas of focal collapse in lungs
- Prominent lymph nodes and thymus
- Gastric contents
Autopsy special investigations
- Sterile heart blood and lung swabs for culture
- Liver and lung for virological culture
- Blood for HIV (used to be taken)
- Swabs of middel ear if otitis suspected
- Swabs of ileal content if GE suspected / present (MCS)
- Complete organ histology
Histology
Also non-specific (!)
Lungs:
- Peribrochial lymphocyte infiltration
- Visceral pleural petechial haemorrhages
- Congestion and edema
- Intra-alveolar hemmorage
- Atelectasis and collapse
Heart:
- Subepicardial petechial haemorrhages
Larynx and trachea
- Mild acute, or chronic inflammation
Theories regarding SIDS
- Hyper- / hypothermia
- Poisoning – CO / CO2
- Smothering
- “Overlaying”
- Allergies, cows milk of HDM
- Infections – tracheobronchitis, RSV, influenza, CMV, Cox B virus
- Metabolic – enzyme defects, hypoglycaemia, hypothyroidism
- Vitamin deficiencies: Ca, vit C, D, E, thiamine and Mg
- Heart – conduction system abnormalities
- Brain
➡️narrow foramen magnum
➡️Medullary serotonin network deficiency
➡️abnormal vagus nerve - Lungs – depletion of, or abnormal surfactant
- Sleep apnea
- Immune deficiency
- Nasal obstruction
Current
- Child must be compromised by a number of factors
- These factors must all occur in the baby at the same time (cumulative effect) to cause death
- So-called TRIPLE RISK MODEL
- Factors:
➡️Sleep – suppression of brainstem
➡️Virus infection (specifically respiratory tract)
➡️Prematurity and low birth weight
Brainstem hypothesis in SIDS
Slide 26 & 27
Genetic + unknown + environmental
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Abnormal medullary 5-HT system= vulnerable infant
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- decreased CO2 sensitivity
- arousal deficit
- respiratory pattern abnormality
- altered BP recovery
- altered temp control
- altered airway reflexes
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