Concussion
DEFINITION
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A concussion is a traumatic brain injury that alters the way your brain functions. Effects are usually temporary but can include headaches and problems with concentration, memory, balance and coordination.
Although concussions usually are caused by a blow to the head, they can also occur when the head and upper body are violently shaken. These injuries can cause a loss of consciousness, but most concussions do not. Because of this, some people have concussions and don’t realize it.
Concussions are common, particularly if you play a contact sport, such as football. But every concussion injures your brain to some extent. This injury needs time and rest to heal properly. Most concussive traumatic brain injuries are mild, and people usually recover fully.
CAUSES
Your brain has the consistency of gelatin. It’s cushioned from everyday jolts and bumps by cerebrospinal fluid inside your skull. A violent blow to your head and neck or upper body can cause your brain to slide back and forth forcefully against the inner walls of your skull.
Sudden acceleration or deceleration of the head, resulting from certain events such as a car crash or being violently shaken, also can cause brain injury.
These injuries affect brain function, usually for a brief period, resulting in signs and symptoms of concussion.
A brain injury of this sort may lead to bleeding in or around your brain, causing symptoms such as prolonged drowsiness and confusion that may develop right away or later.
Such bleeding in your brain can be fatal. That’s why anyone who experiences a brain injury needs monitoring in the hours afterward and emergency care if symptoms worsen.
SYMPTOMS
The signs and symptoms of a concussion can be subtle and may not be immediately apparent. Symptoms can last for days, weeks or even longer.
Common symptoms after a concussive traumatic brain injury are headache, loss of memory (amnesia) and confusion. The amnesia, which may or may not follow a loss of consciousness, usually involves the loss of memory of the event that caused the concussion.
Signs and symptoms of a concussion may include:
- Headache or a feeling of pressure in the head
- Temporary loss of consciousness
- Confusion or feeling as if in a fog
- Amnesia surrounding the traumatic event
- Dizziness or “seeing stars”
- Ringing in the ears
- Nausea
- Vomiting
- Slurred speech
- Delayed response to questions
- Appearing dazed
- Fatigue
Some symptoms of concussions may be immediate or delayed in onset by hours or days after injury, such as:
- Concentration and memory complaints
- Irritability and other personality changes
- Sensitivity to light and noise
- Sleep disturbances
- Psychological adjustment problems and depression
- Disorders of taste and smell
Symptoms in children
Head trauma is very common in young children. But concussions can be difficult to recognize in infants and toddlers because they may not be able to describe how they feel. Nonverbal clues of a concussion may include:
- Appearing dazed
- Listlessness and tiring easily
- Irritability and crankiness
- Loss of balance and unsteady walking
- Crying excessively
- Change in eating or sleeping patterns
- Lack of interest in favorite toys
When to see a doctor
See a doctor within 1 to 2 days if:
- You or your child experiences a head injury, even if emergency care isn’t required
The American Academy of Pediatrics recommends that you call your child’s doctor for advice if your child receives anything more than a light bump on the head.
If your child doesn’t have signs of a serious head injury, and if your child remains alert, moves normally and responds to you, the injury is probably mild and usually doesn’t need further testing. In this case, if your child wants to nap, it’s OK to let him or her sleep. If worrisome signs develop later, seek emergency care.
Seek emergency care for an adult or child who experiences a head injury and symptoms such as:
- Repeated vomiting
- A loss of consciousness lasting longer than 30 seconds
- A headache that gets worse over time
- Changes in his or her behavior, such as irritability
- Changes in physical coordination, such as stumbling or clumsiness
- Confusion or disorientation, such as difficulty recognizing people or places
- Slurred speech or other changes in speech
Other symptoms include:
- Seizures
- Vision or eye disturbances, such as pupils that are bigger than normal (dilated pupils) or pupils of unequal sizes
- Lasting or recurrent dizziness
- Obvious difficulty with mental function or physical coordination
- Symptoms that worsen over time
- Large head bumps or bruises on areas other than the forehead in children, especially in infants under 12 months of age
Athletes
No one should return to play or vigorous activity while signs or symptoms of a concussion are present.
Experts recommend that an athlete with a suspected concussion not return to play until he or she has been medically evaluated by a health care professional trained in evaluating and managing concussions. Children and adolescents should be evaluated by a health care professional trained in evaluating and managing pediatric concussions.
Experts also recommend that adult, child and adolescent athletes with a concussion not return to play on the same day as the injury.