Review of: Lang ES, Andruchow JE: What is the preferred first-line therapy for status epilepticus? Annals of Emergency Medicine. 2006. 48:98–100.
This abstract, which appeared in Annals of Emergency Medicine, strives to provide support for Evidence-Based Emergency Medicine (EBEM). The abstract is based on a systematic review from the Cochrane Database of Systematic Reviews titled "Anticonvulsant therapy for status epilepticus" 2006, Issue 1, article number CD003723. The Cochrane Database is one of the most respected databases of scientific literature and allows researchers the ability to perform quality comparisons of studies (aka, a meta-analysis) to determine the trend for or against a particular intervention.
This abstract supports the routine use of lorazepam intravenously as the first-line drug of choice to stop status epilepticus, which the authors define as seizure activity lasting more than 30 minutes or two or more consecutive seizures without a return to full consciousness. Lorazepam was clinically significant to both diazepam and midazolam at stopping seizure activity. However, there was no difference between the agents in regard for the need to provide ventilatory support or other complications.
It's important that our practice of both in- and out-of-hospital medicine be based on evidence. Sometimes, the only way to make a decision regarding best practice is to examine the results of many studies that include all possible patient populations. The Cochrane Database provides this type of resource.
In this case, the questions is whether to use lorazepam or diazepam for status epilepticus. However, the definition of status as used by the authors isn't consistent with that used by EMS, which usually defines it as seizure activity lasting no more than 10 minutes. We generally don't like to transport patients actively seizing and will give them a minute or two (however long it takes to get the IV started) and then treat them.
Whether the same findings regarding lorazepam woul hold true for prehospital seizure control isn't clear, and no randomized controlled studies exist. Therefore, we're left to extrapolate this study into our practice.
The take home message is that at least there is no disadvantage to using lorazepam over diazepam. Although it has been the opinion of many, including myself, that lorazepam results in less respiratory suppression, this study indicates there is no difference. But that may be true only with regard to status epilepticus where the patient is more profoundly acidotic. Further studies are needed to determine what amount of each of these medications is needed to stop the types of seizure activity frequently seen in EMS before we can make an evidence-based decision.