Administration of Diastat® is an extremely easy, safe and effective means of controlling cluster or status seizure activity in adults and children over age 2.
Sweeping changes to the National Standard Curriculum in 1994 allowed EMT-Basics to assist patients with self-administration of lifesaving rescue medications. Prior to 1997, no rescue medication was available for a life-threatening condition like status epilepticus or prolonged seizure activity. The development of Diastat® in the mid-1990s has provided an easily administered, efficient and safe method of treating prolonged seizure activity. Given the safety and efficacy of this medication and procedure, it is the next logical step in the expanding scope of practice for EMT-Basics and should be added to the approved list of assisted rescue medications contained in the next revision of the National EMS Education Standards and Instructional Guidelines.
In 1994, the National Highway Traffic Safety Administration released its revised National Standard Curriculum for EMT-Basics, with a number of new cognitive and manipulative skill sets that included assisting patients with the self-administration of prescribed rescue medications like nitroglycerin, oral glucose, inhalers and epinephrine auto-injectable pens. The rationale behind basic level-assisted administration was that the patient had already been evaluated by a physician and prescribed the medications for self-administration. Second, the benefit of timely administration of these prescribed medications far outweighed any inherent risks that could be recognized in the prehospital setting. Strict guidelines and protocols have been attached to these new responsibilities, which continue to be outlined in the 2009 National EMS Education Standards and Instructional Guidelines.
Diazepam Use in Seizures
Diastat®--diazepam rectal gel and its trademark administration system-- was first approved for use by the Food and Drug Administration in the United States in 1997 as a treatment for breakthrough seizures in adults and children over age 2. This Schedule IV CDS is currently the only FDA-approved treatment for status epilepticus (SE) or other life-threatening seizures in this age group.1 It was specifically developed for use by parents, caregivers and other nonmedical personnel, and is therefore designed to be easy and safe to administer outside a clinical setting.2
Most seizure patients, no matter how well managed through maintenance medication, will likely experience breakthrough seizures throughout their lifetime. Possibly as many as 35% of patients on antiseizure medications may not be adequately controlled.3 Although these occasional breakthrough seizures are mostly benign, extended, cluster or repetitive seizure activity can lead to life-threatening consequences. Cluster seizures, also referred to as acute repetitive seizures, are best defined as numerous seizures that occur over a time period from minutes to hours and generally fall outside of what would be considered normal for that patient.4 Progression of these types of seizures can manifest as status epilepticus, which should be considered a true medical emergency that can be identified by a number of clinical scenarios. Any generalized seizure lasting more than five minutes or any three consecutive seizures over a one-hour period would be classified as status in nature. SE would also include any type of recurrent seizure without a recognizable postictal recovery period. Finally, any other type of seizure (e.g., partial complex or focal) lasting more than 30 minutes would be defined as SE.5 Between 50,000 and 200,000 generalized convulsive status epilepticus (GCSE) seizures occur every year in the United States, with an overall mortality rate of 20%.6 Additional statistics show that status seizures lasting more than one hour have a mortality rate of 32%, compared with 2.7% for seizures of shorter duration.7 Although the etiology of the seizure and age of the patient are contributing factors, it is clear that morbidity and mortality associated with status epilepticus are directly related to duration of the seizure activity. Therefore, timely administration of an effective anti-convulsant and subsequent termination of seizure activity would be considered a lifesaving intervention.
Diastat® is simply diazepam formulated into a special water-soluble rectal gel and packaged by Valeant Pharmaceuticals in its own trademark, AcuDial, delivery system. Diazepam is commonly given intravenously for seizures and is thought to increase activity of gamma-aminobutyric acid (GABA), which is the primary inhibitory transmitter in the central nervous system.8 Diazepam is rapidly dispersed to the tissues, particularly the brain, and has half-life estimates that range from 20 up to 200 hours. Diastat® has the same types of contraindications, drug interactions and side effects as generic diazepam.
The primary advantage of rectal administration is that it is not necessary to gain intravenous access to introduce a therapeutic amount of diazepam into the system. Although the rate of absorption is slightly less than that of IV administration, rectal administration is very effective and faster than either intramuscular or oral routes. This slower absorption rate of rectally administered diazepam is advantageous, however, in that it decreases the risk of respiratory depression that is often associated with IV administration of benzodiazepines.9 This risk is enhanced with IV administration of diazepam due to a sudden spike in plasma concentrations of the drug.10 Rectal administration does not produce these rapid elevations and therefore does not carry a significant risk of respiratory depression.
Diastat® has proven to be extremely safe for the prehospital and non- medical settings. The manufacturers of Diastat® report that during initial trials, no events of respiratory depression occurred. These trials included patients who received as much as 180% of the recommended dose. Additionally, two of the patients in the study received “twice the target dose with no adverse effects reported.”11 In one specific case, 330% of the recommended dose was reported to have produced no signs of respiratory or cardiac depression.10 Moreover, an American Epilepsy Society 2000 abstract titled Respiratory Effects of Rectally Administered Diazepam (Diastat®) in Pediatric Epilepsy Patients: A Retrospective Study concluded: “The data show that Diastat® had little or no effect on respiration when administered to this population of pediatric epilepsy patients suffering from prolonged or cluster seizures. Results confirm the overall safety and efficacy of rectally administered diazepam in this treatment population.”12
Equally as impressive as its safety record is the documented efficacy of Diastat®. Clinical trials by the manufacturer indicate that 85% of the patients who received the preparation resolved their seizure activity without further intervention; 71% of these patients remained seizure free for 12 hours after resolution of the initial activity.11 A recent study of adult patients conducted by the University of Kentucky found that Diastat® stopped seizure activity in 90% of the patients who were enrolled.3 Overall, administration of rectal diazepam is considered to be a rapid and effective treatment for life-threatening seizure activity.
Currently, a number of states and local jurisdictions allow school nurses, as well as personal care assistants and other nonmedical paraprofessionals to administer prescribed Diastat® in the public school and daycare settings prior to arrival of EMS professionals. This accommodation did not come without controversy from both the school systems and other organizations. Ultimately, the courts have affirmed the individual's right to receive this life- saving intervention by applying case law as it relates to the Individuals with Disabilities Education Act (formerly the Education for All Handicapped Children Act of 1975), Title II of the Americans with Disabilities Act, and Section 504 of the Rehabilitation Act.13 In essence, the argument of schools and daycare systems was that they did not have qualified staff to administer such medications.13 The courts disagreed, indicating that Diastat® and other medications are a required accommodation for children needing such an intervention and thus must be provided in these educational environments. Overall, it has been determined that Diastat®, which was developed and approved by the FDA for safe administration outside a medical setting, is sufficiently safe to be administered by trained caregivers and paraprofessionals as part of each student's required emergency care plan in school.
Diastat® administration is simple and safe. The AcuDial system, which was approved by the FDA in 2005, is a preloaded adjustable-dose plastic syringe with a tapered tip designed for rectal administration of the product. It is loaded with a maximum dose of 10 or 20 mg of diazepam, with adjustments of 2.5 mg increments down to a low dose of 2.5 mg. A pharmacist simply dials the syringe to the physician's prescribed dosage before it is dispensed to the patient. The lock, indicated by a visible green line on the syringe, minimizes the possibility of a dosage error during administration. The caregiver simply removes the protective cap and applies a water soluble jelly to the tip to ease insertion into the rectum. The seizing patient is placed in the semiprone side or left lateral Sims position. The caregiver then spreads the cheeks of the buttocks to visualize the anus for insertion of the device. The tip is gently inserted into the rectum until the hub makes contact with the anus and the medication is dispensed by slowly pressing on the plunger. The device is removed and the cheeks of the buttocks held closed to minimize the possibility of leakage from the cavity. Under most circumstances, the seizure should resolve within 5-15 minutes.
Administration of Diastat® is an extremely easy, safe and effective means of controlling cluster or status seizure activity in adults and children over age 2. Rapid intervention with this vital medication can save lives, minimize neurologic damage and prevent many emergency room admissions. This product was specifically designed for use outside a clinical setting by parents, caregivers and other nonmedical personnel, and is a proven delivery system shown safe and effective for more than 15 years. It is currently being administered in schools by trained caregivers and at home by parents as a rescue medication. With proper guidelines, protocols and training regarding the specifics of this drug, it is an ideal and appropriate prescribed rescue medication that can be used by basic EMTs to assist patients who are unable to help themselves. Proper administration of this intervention requires a simple skill set that is straightforward and easy to master, similar to that of medications already included on the assisted medication list.14 It is clear that the benefit of rapid assisted intervention with this prescribed medication far outweighs any inherent risks that could be recognized in the prehospital setting. There is a strong argument that Diastat® should be included in the list of prescribed medications EMT-Basics are allowed to assist in administering. It should be considered one of the next logical steps in development of the expanding role for EMT-Basics. I also recommend including it in the next revision of the National EMS Education Standards and Instructional Guidelines.
1. Valeant Pharmaceuticals. About Diastat. www.diastat.com/1-About/.
2. Valeant Pharmaceuticals. Uncompromised Safety of Diastat AcuDial. www.diastat.com.
3. Fakahoury T, Chumley A, Owen MB, University of Kentucky, Department of Neurology. Effectiveness of diazepam rectal gel in adults with acute repetitive seizures and prolonged seizures: A single-center experience. Epilepsy and Behavior.Elsevier Inc., 2007.
4. Study Gives Thumbs Up to Home Therapy for Seizure Clusters. www.epilepsyfoundation.org.
5. Neuroland. Status Epilepticus (SE). http://neuroland.com/nn/_index.htm.
6. Huff SJ. Status Epilepticus. http://emedicine.medscape.com/article/793708-overview.
7. Varelas M. Management of status epilepticus seizures and critical care seizures. In P. Varelas & M. V. Spanaki, eds. Seizures in Critical Care, pp. 305-364, Humana Press, 2005.
8. RxList Inc. Diastat Clinical Pharmacology Mechanism of Action. www.rxlist.com/diastat-drug.htm.
9. Murphy P. Pediatric Seizures. Journal of Emergency Medical Services, 22(11):pp. 62-67, 1997.
10. Pellock JM. Safety of Diastat, a rectal gel formulation of diazepam for acute seizure teatment. Virginia Commonwealth University. Adis Data Information BV, 2004.
11. Valeant Pharmaceuticals. Efficacy that lasts: Diastat AcuDial. www.diastat.com.
12. Bettis DB, Grey P. Respiratory effects of rectally administered diazepam (Diastat) in pediatric epilepsy patients: A retrospective study. www.aesnet.org.
13. Carpenter JA. (n.d.). Diastat administration in schools: Summary of relevant federal laws and selected cases. http://www.epilepsyfoundation.org/epilepsylegal/upload/diastatschool.pdf.
14. RxList Inc. Diastat, Clinical Pharmacology, Clinical Studies; Fig 2, Caregivers Overall Global Assessment. www.rxlist.com/diastat-drug.htm.
Matthew Knoblauch, AAS, NREMT-P, is a retired fire captain/paramedic and currently owns and operates Northlake Emergency Services Consulting LLC in Abita Springs, LA. He is a certified emergency manager in Louisiana, as well as an associate emergency manager with the International Association of Emergency Managers. He has worked in various disciplines, including public and private EMS services, law enforcement and the fire service.