Progression of TBI Symptoms
Symptoms typically progress through three successive stages:
Severe TBI usually results in coma, a loss of consciousness. When in a coma, the patient's eyes are closed and he or she shows no reaction when spoken to, touched, or pinched. Some patients demonstrate a reflexive movement, such as a handgrip, when an arm or leg is touched or squeezed. A coma can be brief or can persist for hours, days, weeks, months, or even years. The longer a person is unconscious, the more severe the injury, and the greater the chance for permanent neurological damage. (more about coma)
A concussion is a brief (seconds to minutes) loss of consciousness caused by a blow to the head. The prognosis for recovery usually is good.
Post-traumatic Amnesia Symptoms
Once a patient responds with purposeful movement or attempts to communicate, he or she has progressed to post-traumatic amnesia (PTA). Purposeful movements include obeying a command to close the eyes or lift a limb and attempts to communicate by speaking, mouthing words, and/or gesturing.
PTA is a state of acute confusion. The hallmark of this stage is cognitive impairment (i.e., problems with perception, thinking, remembering, and concentration). During this stage, patients often cannot concentrate long enough to capture anything in their memory. The most common symptoms of PTA associated with TBI include the following:
- Answering the same question, asked repeatedly, with different responses
- Difficulty performing simple tasks, such as counting to 10 and reciting days of the week or months of the year
- Distractibility, attention jumps from one subject to another
- Inability to remember what happened in the preceding minutes, hours, or days
- Losing train of thought while responding to a question
- Responding inconsistently, vaguely, or tangentially
- Staring blankly at an observer
Behavioral changes often occur during PTA and the patient may be uncharacteristically quiet and passive, or aggressive and agitated. A patient may manifest disinhibitionsaying or doing things that come to mind which typically are not acted uponsuch as making inappropriate comments about someone's physical appearance (e.g., "You look really sexy."). Impulsivity is also common. For example, a patient may abruptly try to get out of bed, even with both legs in casts.
Patients usually have little or no awareness of these cognitive and behavioral impairments and typically remember nothing of their actions or what happened to them during PTA, even though they were fully conscious.
When patients begin retaining informationsuch as the current month and year, where they are or why they are in the hospitalthey have emerged from PTA and entered into the recovery phase. This can last weeks, months, or years, depending on which areas of the brain are damaged, and the severity of that damage. Recovery is characterized by progressive improvement in cognitive and behavioral functions. Sometimes behavior becomes more difficult when the patient becomes aware of his or her new limitations, resulting in frustration and depression that can be difficult to treat because of cognitive impairments.
Gains typically occur fairly rapidly at first, but the speed of improvement slows over months and years until a recovery plateau is reached. The more severe the injury, the longer it takes to plateau. Even when the patient's rate of improvement seems to stabilize, subtle, recognizable improvements may continue. These late changes develop very slowly and are so subtle that, unless specifically watched for, they may go unrecognized. They usually do not significantly impact the patient's functional status or the amount of supervision or support needed.