What is Coma or What is meant by Coma ?
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| Credits : Aaron Cohen, CC BY-SA 3.0 Wikimedia Commons |
The state of awakeness in an individual is regulated by the upper portion of the brain stem, which serves as the connection between the cerebrum and the spinal cord. This control is facilitated through a network of nerve cells and fibres known as the reticular activating system. The cerebrum, comprising the right and left hemispheres, cooperates with the upper part of the brain stem to maintain consciousness and alertness. Now in normal circumstances, the brain can quickly adjust the level of activity and consciousness as needed. It makes adjustment based on the information provided by its 5 senses of the body namely ears, eyes, mouth, skin and nose. For example, the brain brings adjustments in its metabolic activity and energy level and thus induces sleep.
What weakens the consciousness of the brain ?
The brain’s
ability to adjust its activity, energy and consciousness levels is weakened in
the following circumstances:
· Impaired brain function and consciousness adjustment occur when
both cerebral hemispheres malfunction, particularly due to sudden and severe
damage.
· Dysfunction of the reticular activating system contributes to the
impairment of the brain's ability to modulate activity and consciousness
levels.
· Other contributing factors to impaired adjustment include severe
sleep deprivation.
· Immediate post-seizure periods result in compromised activity and
consciousness levels.
· Reduced blood flow or nutrient supply to the entire brain leads to
impaired adjustment.
· Diminished blood flow to specific brain regions, such as in
certain strokes, contributes to impairment.
· Toxic substances damaging nerve cells or affecting their function
result in impaired adjustment.
· Bleeding, swelling, brain tumours, or injury causing pressure on
parts of the brain lead to compromised activity and consciousness levels.
What are the causes of Coma ?
Most
common causes of impaired consciousness (lethargy, obtundation, stupor, coma)
as per the studies of Merck
Manual are :
1.
Toxic substances:
e.g., carbon monoxide
2.
Drugs: e.g.,
alcohol, opioids, sedatives
3.
Metabolic
abnormalities: e.g., low/high blood sugar levels (hypoglycaemia, hyperglycaemia)
4.
Disorders causing
nerve cell malfunction: e.g., liver failure, kidney failure
5.
Severe
infections: e.g., meningitis, brain abscess
6.
Infections
elsewhere in the body: e.g., sepsis
7.
Severe or
prolonged seizures
8.
Inadequate blood
flow to the brain: e.g., cardiac arrest
9.
Head injuries:
e.g., concussion, bleeding in or around the brain
10.
Disorders
increasing intracranial pressure: e.g., certain brain tumours, strokes
11.
Disorders
interfering with the delivery of substances to the brain or affecting their
utilization:
· Low/high blood sugar levels: hypoglycaemia, hyperglycaemia
· Low oxygen levels in the blood: respiratory or heart failure
· Stopping of heart’s pumping or breathing: cardiac arrest,
respiratory arrest
· Diseases affecting blood flow to the brain
12.
Specific
disorders affecting cells throughout the body:
· Liver failure
· Kidney failure
· Underactive thyroid gland (hypothyroidism)
· Abnormal body temperature: hypothermia or hyperthermia
· Low/high levels of calcium or sodium in the blood
· Thiamine(Vitamin B1) deficiency
13.
Disorders
affecting areas of the brain controlling consciousness:
· Head injuries causing bleeding or damage to control areas
· Strokes and tumours directly damaging control areas
· Disorders increasing intracranial pressure indirectly affecting
consciousness
· Structural abnormalities blocking cerebrospinal fluid flow
· Large masses pushing the brain, causing damage and potential
herniation
14.
Substances
causing impaired consciousness:
· Excessive alcohol or drug consumption: sedatives, opioids
· Interactions between multiple drugs
· Marijuana overdoses
· Neuroleptic malignant syndrome from certain antipsychotic drugs
What are the symptoms of Coma ?
Among all the symptoms of coma, here is the list of six most common symptoms faced by the patients (If you face them, let your doctor know about it):
1. Impaired Consciousness: Consciousness is significantly impaired,
ranging from a stupor (responsive to vigorous stimulation) to a complete lack
of arousal in a coma, where individuals are unconscious with closed eyes and
cannot be awakened.
2. Abnormal Breathing Patterns: The pattern of breathing is often abnormal,
including rapid, slow, deep, or irregular breathing. Alternating between these
abnormal patterns is also observed.
3. Blood Pressure Fluctuations: Blood pressure may fluctuate, either
increasing or decreasing, depending on the underlying cause of impaired
consciousness. For instance, head injuries causing bleeding in the brain may
lead to increased pressure within the skull, prompting a response to elevate
blood pressure.
4. Muscle Contractions: Muscles may contract and remain in unusual
positions. Decerebrate rigidity involves tilting the head back with extended
arms and legs, while decorticate rigidity features flexed arms with extended
legs. Sporadic or involuntary muscle contractions can also occur.
5. Eye Abnormalities: The eyes may be affected, with one or both
pupils dilated and unresponsive to light changes. Alternatively, pupils may be
constricted. Abnormal eye movements or a lack of movement may also be observed.
6. Additional Symptoms: The underlying disorder causing impaired
consciousness may manifest other symptoms. For example, if the cause is
meningitis, early symptoms may include fever, vomiting, headache, and a stiff
neck, making it difficult to lower the chin to the chest. These additional
symptoms provide crucial diagnostic clues.
Neurological assessment in coma patients
Physicians use the Glasgow Coma Scale (GCS) to evaluate the extent of impaired consciousness in individuals facing various acute medical conditions and trauma. I have already made an article (click here to read) on it read that for further information.
What is the Treatment for Coma ?
Measures to help
people breathe and improve blood flow to the brain are very important for
treating coma. Immediate action is required if an individual is rapidly
becoming less alert and difficult to arouse, as this signals a medical
emergency. Emergency medical personnel initiate the first steps, checking the
airway, ensuring adequate breathing, and assessing pulse, blood pressure, and
heart rate. Corrective measures should be taken if any issues are identified.
Patients are
initially treated in an emergency department and subsequently admitted to a
hospital intensive care unit for continuous monitoring. Nurses closely monitor
vital signs such as heart rate, blood pressure, temperature, and oxygen levels.
Abnormalities are promptly corrected to prevent further brain damage. Oxygen is
administered immediately, and intravenous lines are inserted for the quick
delivery of drugs or glucose. Temperature management is crucial in cases of
very high or low body temperature. Concurrent disorders, such as heart or lung
issues, are also addressed. Blood pressure is closely monitored to ensure it
remains within normal ranges, preventing complications like stroke.
Treatment of the
underlying cause is prioritized. For low blood sugar levels, intravenous
glucose is administered, often with thiamine to address Wernicke encephalopathy
in cases of undernourishment, particularly due to alcohol abuse. In head
injuries, neck immobilization is essential, and certain drugs like amantadine
may aid nerve cell function. Suspected opioid overdoses are treated with the
antidote naloxone.
In cases of ingesting toxic substances within an hour, rare instances may
involve pumping the stomach or administering activated charcoal to prevent
further absorption.
For those in a
deep coma, breathing support is essential, often requiring a breathing tube and
mechanical ventilation. Mechanical ventilation, achieved through endotracheal
intubation (yes, some nerdy terms are necessary here), ensures proper
oxygen delivery, preventing inhalation of stomach contents. Sedatives may be
used to manage agitation induced by mechanical ventilation. The management of
increased pressure within the skull involves measures like elevating the head
of the bed and using mechanical ventilation for hyperventilation. Diuretics or
other drugs may be employed to reduce brain fluids, and sedatives may be given
to control muscle contractions or agitation. Blood pressure is lowered if
excessively high, and drains may be inserted into the ventricles of the brain
to drain cerebrospinal fluid.
For how much time will the coma remain ?
Coma vs. Vegetative State vs. Stupor - What’s the Difference ?
Now you will
definitely be confused in the above terms and could ask me are stupor and coma
the same thing? Or aren’t all of them the same? Well let me clarify them for
you.
Coma: A coma is a state of profound unconsciousness
in which an individual is unresponsive to external stimuli and cannot
be awakened. It involves a complete loss of consciousness, with no awareness of
self or the surrounding environment. Typically, the eyes remain closed, though
there might be brief periods of eye opening. The duration of a coma can vary,
ranging from temporary to prolonged, depending on the underlying cause. Motor
responses in a coma are minimal, and there is little to no purposeful movement.
Vegetative
State (Unresponsive Wakefulness Syndrome): In opposite of it, a vegetative state is
characterized by intermittent periods of wakefulness with an overall lack of
responsiveness and awareness. A person in a vegetative state may experience
spontaneous eye opening, but this does not correspond to purposeful responses.
The state can be prolonged, indefinite, and while there may be involuntary
movements, there is no meaningful awareness of self or surroundings.
Stupor: Stupor represents a state of reduced consciousness where an individual is in a daze, responding minimally to stimuli and appearing lethargic. While consciousness is markedly reduced, it is not completely absent. Awareness is limited, and responses to stimuli are often delayed and minimal. Eye opening may be reduced, and there might be some responsiveness to stimuli. The duration of stupor can vary depending on the underlying cause, and motor responses are limited, including slow or minimal reactions to external stimuli.
The Miracle Story of The Coma Patient I Heard About
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| Credits to : Wikipedia |
I have heard the
story of Martin Pistorious, the mysterious onset of his illness in South Africa
left doctors puzzled, leaning towards a diagnosis of cryptococcal
meningitis. As his condition relentlessly worsened, he gradually lost the
ability to move, speak, or engage with his family through eye contact.
Despite the
predictions from experts, his family sticked to a steadfast routine for 12
years. Each morning, his father diligently rose at 5 a.m., dressing Martin and
transporting him to the care centre. Evenings were marked by a meticulous
routine: a bath, dinner, and tender placement into bed. An alarm, faithfully
set every two hours, resonated to ensure Martin's body was turned, preventing
the onset of bed sores.
Around 1992, the
once immobilized Martin has emerged from the shadows of his affliction. Armed
with a computer as his voice and propelled by a wheelchair, he has reclaimed
mobility and the power of speech. In his poignant memoir, "Ghost Boy: My
Escape From A Life Locked Inside My Own Body," Martin chronicles his
recollections from those 12 years of silent captivity.
In those years of
seeming invisibility, Martin endured the torment of being trapped within his
own unresponsive body, a silent witness to the world around him. As he emerged
from the shadows, he recalled the mundane yet agonizing moments, like being
subjected to mind-numbing children's shows. The mention of Barney, a staple in
the routine of the care centre, triggers Martin's vivid disdain.
The narrative takes a sombre turn when Martin recalls hearing his mother express a desperate wish for his death. Joan Pistorious, fraught with guilt over these words, carried the weight of her own desperation and sorrow for her son's seemingly bleak existence. Martin, displaying an extraordinary capacity for empathy, understands the depth of his mother's despair, encapsulating a tale of resilience and understanding in the face of profound adversity.
References : As we come to the end of the article, I would like to give special credits to Merck Manual for the information they have provide us with and also Mayo Clinic for the same.