Your patient arrives by ambulance having a seizure. EMS administered ativan 10 minutes ago. You give a second dose but the seizure continues. What should you do?
Status Epilepticus (SE)
Definition:
Seizures that are prolonged or recur before the patient fully recovers.
The exact meaning of prolonged is evolving. Most seizures are brief, resolving spontaneously in less than 1-2 minutes. It is known from animal studies that within minutes of a non-resolving seizure there are synaptic changes that quickly lead to neuropeptide expresion changes and ultimately excitotoxicity that “culminates in neuronal death.” [2] Prolonged seizure duration results in treatment resistance, especially to benzodiazepines. [1] Based on this and proven benefit to early treatment, it is now defined that convulsive SE must be treated within 5 minutes, [1,3] and any patient who arrives having a seizure should be considered to have SE.
Beware of of patients who remain unresponsive after initial treatment, as nonconvulsive SE is seen in nearly 50% of comatose patients after control of convulsive SE. [1] In one study, mean unresponsive time after generalized convulsion (by video monitoring) is 4 minutes and max 20 minutes before non-respiratory movement. [4] If your patient is not moving within 20 minutes of cessation of convulsion suspect status!
This short time frame has led to a focus on initiating treatment in the prehospital setting. algorythmic prehospital and emergency care is effective in reducing the duration of SE.
- Treatment: (protocol from [2])
- Within 5 minutes: Lorazepam 4mg IV, repeat x 1 in 5 minutes
Alt: midazolam 10mg IM, diazepam 20mg PR- under/late dosing decrease treatment efficacy
- remeber ABC, IV, monitoring
- labs: cbc, bmp, Ca, Mg, Po4, LFT, trop, AED levels, blood gas
- glucose level, treat with thiamine then glucose
- within 30 minutes: Fosphenytoin then midazolam (can also complete simultaneously)
-Fosphenytoin 20mg/kg up to 150mg/min
-Midazolam: 0.2mg/kg q 5 minutes (max 2mg/kg), start drip 0.2mg/kg/h
Alt: valproate, levetiracetam, lacosamide- Some protocols beginning to favor directly moving to anesthetics skipping this phase… time is brain
- >30 minutes: ICU, treatment with continuous EEG, neurologist
–pentobarbital 5mg/kg q 5 then drip or propofol 1-2mg/kg q5 min then drip
- Within 5 minutes: Lorazepam 4mg IV, repeat x 1 in 5 minutes
Fosphenytoin is the prodrug of phenytoin. It is more expensive. Less hypotension. faster infusion. both drugs cause arrythmia and respiratory depression. both have many drug-drug interactions. [2]
References:
1)Betjemann, John P., and Daniel H. Lowenstein. “Status Epilepticus in Adults.” The Lancet Neurology 14.6 (2015): 615-24. Web.
2)Arbo, John E., Stephen Ruoss, Geoffrey K. Lighthall, Michael P. Jones, and Joshua Stillman. Decision Making in Emergency Critical Care: An Evidence-based Handbook. N.p.: n.p., n.d. Print.
3)Lowenstein, Daniel H., Thomas Bleck, and Robert L. Macdonald. “It’s Time to Revise the Definition of Status Epilepticus.” Epilepsia 40.1 (1999): 120-22. Web.
4) Seyal, Masud, Lisa M. Bateman, and Chin-Shang Li. “Impact of Periictal Interventions on Respiratory Dysfunction, Postictal EEG Suppression, and Postictal Immobility.” Epilepsia 54.2 (2012): 377-82. Web.
