Article Preview
TopIntroduction
Traumatic brain injury is the most common cause of new onset epilepsy in young adults. Approximately 20-25% of severe traumatic brain injury patients will have seizures (abnormal electrical brain discharges) in the immediate period after a head injury. Factors that could tax the resources on an already damaged brain include increased metabolic demands, elevated intra-cranial pressure, and increased neurotransmitter release. Another area of concern is for the 8% of patients who present with unstable cervical injuries. The violent contractions associated with tonic/clonic seizures may aggravate existing cervical injury or cause death since there is only a small amount of space between the spinal cord and the cervical anatomy that normally protects it. In an injury of this nature, much of the space will already be compromised by swelling and inflammation.
Giving antiepileptic medication on a prophylactic basis thus seems to be a logical choice, what could be the down side? Unfortunately, these drugs are associated with adverse effects, some of them fatal. These include cognitive impairments, abnormalities in blood cells, neurologic impairment, and severe skin eruptions. Even though not every patient will experience these side effects, in those that do the results may be serious or fatal. These concerns led the Cochrane commission (http://www.cochrane.org/) to conduct a systematic review which focuses on the recommendations of using antiepileptic on a prophylactic basis.
Resources. This review was initiated by searching the Cochrane Injuries Group specialised register, as well as MEDLINE and the registers of the Cochrane Stroke Group and Cochrane Epilepsy Group. We also contacted pharmaceutical companies who manufacture anti-epileptic agents, the National Institute of Neurological Disorders and Stroke, Epilepsy Division, and the United States’ National Institute of Health.
Why was this review done? The review was done to explore the effectiveness of prophylactic antiepileptic drugs for acute traumatic brain injury and to assess risk to benefit ratios. Does this intervention help sort-term? How does it affect death or disability (long term seizures) and what are the benefits given potential adverse reactions to the drugs?
What did we find? The review found that using anti-epileptic drugs in the early stages after traumatic brain injury does decrease seizures. The review found that anti-epileptic drugs were effective for decreasing seizures in the first week after a TBI. Available pooled data failed to demonstrate reductions in overall mortality, later onset seizures or the development of persistent vegetative states.
There was not enough clear data within the studies collected to investigate cognitive/behavioural, neurological or hematopoietic adverse effects thought to result from the anti seizure medications.