Coma
Introduction:
• Definition - Coma is a deep state of unconsciousness in which a person cannot wake up, cannot respond to sound, touch, or pain, and shows very limited brain activity because the brain is not functioning normally.
• Consciousness VS unconsciousness:
Consciousness - means a person is awake, aware of themselves, and able to respond to what is happening around them.
Unconsciousness - means a person is not aware, cannot respond, and does not have control over their actions or surroundings.
So, coma is a deep form of unconsciousness where the brain is not working normally and the person cannot be woken up.
• Sleep VS Coma:
Sleep:
• Can wake up
• Responds to sound/touch
• Normal brain activity and breathing
Coma:
• Cannot wake up
• No response to sound/pain
• Very low brain activity and abnormal reflexes
Cause:
1. Traumatic causes (head injury)
A strong hit to the head can damage the brain and make a person fall into a coma.
2. Medical causes (stroke, diabetes, infections)
Stroke: Blood flow to the brain stops, causing brain cells to die.
Diabetes: Very high or very low blood sugar can shut down brain function.
Infections: Diseases like meningitis or encephalitis can swell or damage the brain.
3. Toxic causes (poisoning, overdose)
Poisonous chemicals, alcohol, or drug overdose can affect the brain and lead to coma.
4. Oxygen-related causes (cardiac arrest, drowning)
If the brain doesn’t get oxygen for even a few minutes, brain cells get damaged, causing coma.
This can happen after the heart stops (cardiac arrest) or after drowning.
Levels of unconsciousness:
• Alert - The person is fully awake, aware, and responds normally.
• Confused - The person is awake but disoriented and has trouble thinking clearly.
• Stupor - The person is almost unconscious and only responds to strong stimulation (like pain).
• Coma - The person is completely unconscious and cannot be woken up.
• Brain death - There is no brain activity at all; the brain has permanently stopped working.
Alert, confused, stupor, coma, and brain death are levels of consciousness, not all coma.
Only “coma” is an actual coma state.
Alert is the normal state, the opposite of coma. So, alert is not at all à coma state, it’s the normal healthy state.
The list just shows the progression from fully awake → to less responsive → to coma → to no brain activity.
Glasgow coma scale (GCS):
• Definition - The Glasgow Coma Scale measures coma depth by checking eye response, verbal response, and motor response, and the total score shows how severe the coma is.
• Example:
A person opens their eyes when you call their name (Eye = 3), speaks clearly (Verbal = 5), and moves their arm normally (Motor = 6).
Symptoms of coma:
No eye opening – the person’s eyes stay closed.
No response to sound or touch – they don’t react when spoken to or shaken.
No purposeful movement – no controlled actions or movements.
Abnormal breathing – slow, irregular, or unusual breathing patterns.
Weak or absent reflexes – reflexes like blinking or reacting to light may be reduced.
No verbal response – they cannot speak or make meaningful sounds.
Very low brain activity – shown on medical tests like EEG.