After this increase in glucose metabolism, there is a subsequent lower metabolic state which may persist for up to 4 weeks after injury. A completely separate pathway involves a large amount of calcium accumulating in cells, which may impair oxidative metabolism and begin further biochemical pathways that result in cell death. Again, both of these main pathways have been established from animal studies and the extent to which they apply to humans is still somewhat unclear. Diagnosis
Head trauma recipients are initially assessed to exclude a more severe emergency such as an intracranial hemorrhage. This includes the "ABCs" (airway, breathing, circulation) and stabilization of the cervical spine which is assumed to be injured in any athlete who is found to be unconscious after head or neck injury. Indications that screening for more serious injury is needed include worsening of symptoms such as headaches, persistent vomiting, increasing disorientation or a deteriorating level of consciousness, seizures, and unequal pupil size. Those with such symptoms, or those who are at higher risk of a more serious brain injury, may undergo brain imaging to detect lesions and are frequently observed for 24–48 hours. A brain CT or brain MRI should be avoided unless there are progressive neurological symptoms, focal neurological findings or concern of skull fracture on exam.Diagnosis of concussion requires an assessment performed by a physician or nurse practitioner to rule out severe injuries to the brain and cervical spine, mental health conditions, or other medical conditions.
Other factors that may lengthen recovery time after mTBI include psychological problems such as substance abuse or clinical depression, poor health before the injury or additional injuries sustained during it, and life stress. Longer periods of amnesia or loss of consciousness immediately after the injury may indicate longer recovery times from residual symptoms. Other strong factors include participation in a contact sport and body mass size. Pediatric concussion
Most children recovery completely from concussion in less than four weeks, however 15–30% of youth may experience symptoms that last longer than a month. People aged 65+ with concussion
Mild traumatic brain injury recovery time in people over age 65 may have increased complications due to elevated health concerns, or comorbidities. This often results in longer hospitalization duration, poorer cognitive outcomes, and higher mortality rates. Repeat concussion
For unknown reasons, having had one concussion significantly increases a persons risk of having another. Having previously sustained a sports concussion has been found to be a strong factor increasing the likelihood of a concussion in the future. People who have had a concussion seem more susceptible to another one, particularly if the new injury occurs before symptoms from the previous concussion have completely gone away. It is also a negative process if smaller impacts cause the same symptom severity. Repeated concussions may increase a persons risk in later life for dementia, Parkinsons disease, and depression. Post-concussion syndrome
In post-concussion syndrome, symptoms do not resolve for weeks, months, or years after a concussion, and may occasionally be permanent.