A lack of oxygen or excess of carbon dioxide in the body that results in unconsciousness and often death and is usually caused by interruption of breathing or inadequate oxygen supply.
Sometimes, it may be quite obvious when one is suffering from asphyxiation. Asphyxia can be caused by any of the following:
- Choking from food, blood, vomit or broken teeth
- May also occur in unconscious victim when the tongue falls to the back of the throat
- Chest compression or collapsed lung, from road accidents or any penetrating injury to the chest
- Drowning or near drowning
- Gas poisoning
- Carbon monoxide poisoning from home appliances releasing fumes or released by car exhaust or other toxic fumes
- Electrical accidents
- From attempted suicide by hanging or attempt to kill another person by placing grasping the neck
- Severe asthma attack or bronchitis
- Whooping cough
(a) With asphyxia there will be hypoxia/ anoxia and hypercarbia.
The hypercarbia will cause increased secretion of fibrinolysin by the vascular endothelium.
The fibrinolysin will cause:
(i) increased fluidity of blood
(ii) neck veins and right heart distended with blood
(iii) increased hypostatic blood
– The blood will contain increased levels of reduced haemoglobin and this accounts for bluish discoloration (cyanosis) seen both externally and internally. The hypostatic areas will be show deep blue discoloration soon after death.
(b) The anoxia will cause capillary dilatation resulting in increased blood in the tissues. This results in congestion.
(c) The anoxia also caused increase in the capillary permeability resulting in transudation of plasma from the vessels to the tissues. This results in the tissue oedema.
(d) The loss of fluid also causes haemoconcentration which in turn retards the blood flow and stasis. This results in a rise in the intra-capillary pressure leading to rupture. This results in the petechial haemorrhages.
(e) Anoxia also causes disruption of the capillary endothelium which also contribute to the petechial haemorrhages
(f) With anoxia there will be dysfunction of organs / tissues / cells / according to their degree of specialization and cessation of activity of cells / tissues / organs one by one resulting in death.
Any of the following symptoms can lead to asphyxia.
- Difficulty and/ or noisy breathing, which may ultimately lead to cessation
- Rapid pulse
- High blood pressure (hypertension)
- Cyanosis of the face
- Swollen veins on the head and neck
- Slowly losing consciousness
At birth, doctors and nurses check your baby’s condition carefully and give a number rating from 0 to 10. This number is called an Apgar score. The Apgar rates skin color, heart rate, muscle tone, reflexes and breathing effort. A very low Apgar score (0 to 3) lasting longer than five minutes may be a sign of birth asphyxia. A baby who has not had enough blood flow or oxygen to its body may have abnormal breathing, poor circulation, lethargy (lack of energy), lack of urine output and blood-clotting abnormalities.
Asphyxia implies an inadequate delivery of oxygen to the brain. This low oxygen level may be detected with blood gas tests on either the baby’s blood or that of the umbilical cord. Also, when the blood has been low in oxygen for some time, it begins to show other abnormal signs. For example, the blood will become acidic, which can also be detected with blood tests.
The effect of asphyxia generally depends on how long the baby has not had enough oxygen.
Treatment for asphyxia consists of strategies to improve oxygen delivery within the body. Usually, this means delivering oxygen rather than air to the baby, often with mechanical ventilation. Additionally, blood circulation is monitored and, when necessary, improved by giving extra fluids, blood, or drugs to support heart function and blood pressure. A balance must be maintained; if blood pressure is too high, there is a risk of bleeding in the brain.
If severe, asphyxia will also affect other parts of the body as well as the brain. For this reason, any baby with asphyxia will be monitored with special attention to the kidneys, liver, and heart. Asphyxia is most commonly seen in the newborn baby immediately following birth and it is generally only severe cases that will cause death or long-term disability.