Table of ContentsView AllTable of ContentsWhat Coma IsTypes of ComaCausesSignsRating SeverityDiagnosisTreatmentOutlookComa RecoveryRisk FactorsPrevention
Table of ContentsView All
View All
Table of Contents
What Coma Is
Types of Coma
Causes
Signs
Rating Severity
Diagnosis
Treatment
Outlook
Coma Recovery
Risk Factors
Prevention
A coma is a state of deep unconsciousness in which a person is unresponsive for a prolonged time. Although comas have many possible causes, they all involve temporary or permanent harm to the brain, impairing a person’s awareness of their surroundings and their ability to respond to them.
In some situations, a medically induced coma may help prevent brain damage, improving the chances of survival and reducing the likelihood of long-term disability. This article describes the causes of coma, rating scales, and what to expect if your loved one has been diagnosed with a coma.
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What Is a Coma Exactly?
A coma may last for days or longer before a person regains consciousness, but in some situations, a person may never recover from a coma.
The outcome of a coma depends on the severity and cause. Often, the medical cause is treated while a person is receiving respiratory and other support.
What Is a Persistent Vegetative State?A persistent vegetative state is a prolonged condition in which a person might appear to intermittently go from sleeping to awake but remain unresponsive.
What Is a Persistent Vegetative State?
A persistent vegetative state is a prolonged condition in which a person might appear to intermittently go from sleeping to awake but remain unresponsive.
Health conditions can lead to a coma in different ways.
Some of the categories include:
A coma can involve one or more of these physical changes.
What Is the Cause of a Coma?
Several medical conditions can affect a person’s level of consciousness, potentially causing a coma.
The most common causes of coma include:
What Are the Signs of a Coma?
A coma may be diagnosed during a hospital stay or suspected during an emergency response. Often, a coma is diagnosed after a person has been in an unresponsive condition for several hours or longer.
First responders will often describe a person’s state of consciousness using the AVPU scale.
The AVPU scale is:
Healthcare providers diagnose a coma based on a physical examination, diagnostic tests, and assessment of the medical history and recent situation.
Unconsciousness First Aid and Treatment
How Doctors Determine Severity: The Glasgow Coma Scale
The Glasgow Coma Scale (GCS) assigns a severity number to a coma through assessment of physical movements, speaking, and movement. The scale can also help healthcare professionals track improvement, decline, or stability.
The scale provides a maximum possible score of 15, which correlates to a mild coma. The lowest score of 3 indicates a deep coma.
Scoring is based on:
An Overview of Level of Consciousness (LOC)
How Comas Are Diagnosed
When a person is diagnosed with a coma, healthcare providers work to identify the cause. Often, treatment involves medical stabilization to minimize the risk of permanent brain damage.
Diagnosis is based on:
How a Coma Is Treated
Treatment depends on how long a person has been in a coma, the cause, and the likelihood of recovery. Often, particularly when there is a high chance of recovery, the person is cared for in theintensive care unit, where close medical monitoring and quick medication adjustments are possible.
Corticosteroids or diuretics (water pills) canreduce brain swelling.Additionally, support for breathing, blood pressure, and heart function is usually necessary to maintain survival and prevent further brain injury. Medication to help manage any ongoing infections or inflammatory conditions is sometimes necessary.
Coma has many potential complications, which include pneumonia (lung infection or inflammation), skin infections, urinary tract infections, dysregulated body temperature, bowel obstruction, seizures, and more.
After recovery from a coma, rehabilitation can help to strengthen breathing muscles and build muscle strength and control. Many coma survivors will also need speech and swallow therapy.
What’s the Outlook for Someone in a Coma?
Many people can recover from a coma. If your loved one is in a medically induced coma, they are more likely to have a full recovery because the coma-inducing medication can be reversed when they become medically stable.
If your loved one is in a comatose state due to a medical condition or a head injury, then the outlook and potential for recovery are highly variable based on their individual situation.
Recovery from a coma depends on many factors individual to the person and the cause of the coma.
Waking Up From a Coma
Waking up from a coma is usually a gradual process. There may be a delay of hours or days after medical causes are treated before a person starts to become more alert.
If your loved one is waking up from a coma, remain patient and anticipate a slow recovery.
Signs of Coming Out of a Coma
When a person is recovering from a coma, they may periodically open their eyes, begin to move, respond to touch or pain, or toss and turn in bed.They may also cough or try to pull out medical devices, such as intravenous (IV) catheters or breathing tubes.
The Ranchos Scale
The Rancho Los Amigos Cognitive Scale-Revised (RLAS-R) is more detailed than the AVPU scale or the GCS. This scale rates people on 10 levels, based on many factors, including responsiveness, eye movements, need for assistance, memory, cooperation, learning, and more.
Will You Remember Anything That Happened During the Coma?
People do not typically remember anything from when they were in a coma after recovering from one.This is because they are not alert or aware of their surroundings during a coma. Some people may have a slight recollection of the event that caused the coma—such as a car accident—but usually can’t remember most of the details.
What Are the Risk Factors for Comas?
A head injury is the most clear-cut risk factor for a coma. Additionally, health conditions that can lead to rapid alterations in metabolism can also cause a coma. Drug or alcohol use or withdrawal can lead to altered levels of consciousness that can be temporary, permanent, or life-threatening.
Health conditions that are associated with a risk of coma include heart disease, lung disease,cerebrovascular disease(a disease of the blood vessels in the brain), thyroid disorders, diabetes, liver, disease, and kidney failure.
Can You Prevent a Coma?
Prevention of traumatic brain injury is a crucial step for preventing a coma.This includes wearing a seat belt while in a moving vehicle or wearing a helmet for certain contact sports.
Additionally, managing underlying health conditions, such as diabetes or kidney disease, can help prevent metabolic changes that could lead to a coma. Taking care ofstroke risk factors—like high blood pressure, high cholesterol, diabetes, and smoking—can all reduce the risk of a stroke-induced coma.
That said, there is no specific coma prevention strategy. Taking care of your health is the best way to prevent serious brain damage that could lead to unconsciousness.
Summary
A coma is a state of unresponsiveness. People can be diagnosed as being in a coma based on a physical examination, medical history, and diagnostic tests. Several health conditions are known to have the risk of leading to a coma. Many people can recover from a coma, depending on its severity and underlying cause.
If your loved one has been diagnosed with a coma, you need to know that this diagnosis has variable outcomes—and their prognosis relies on many factors. When your loved one is stabilized, their healthcare providers will discuss expectations and treatment plans with you.
9 Sources
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