Seizures, Status Epilepticus, and Neuromuscular Disorders
Seizures, Status Epilepticus, and Neuromuscular Disorders
Status epilepticus is a medical emergency: treat convulsive seizures lasting five minutes or more, and consider electrographic status after ten minutes. Give a benzodiazepine first-lorazepam 0.1 mg/kg (usually 4 mg) or midazolam-repeated once, then a second-line agent: levetiracetam 60 mg/kg, fosphenytoin 20 mg PE/kg, or valproate 40 mg/kg. For refractory status, start a continuous anesthetic infusion (midazolam, propofol, or pentobarbital) with EEG titration, often to burst suppression. Always look for reversible causes: hypoglycemia, hyponatremia, eclampsia, alcohol withdrawal, infection, and autoimmune encephalitis.
Nonconvulsive status epilepticus should be suspected in unexplained coma or persistent altered mentation; obtain urgent EEG. Do not confuse posturing or rigors with seizures. Prophylaxis after a single provoked seizure is usually unnecessary; address the cause.
Neuromuscular emergencies include Guillain–Barré syndrome, myasthenic crisis, and botulism. Monitor vital capacity and negative inspiratory force; intubate for vital capacity below 15–20 mL/kg or rapidly declining respiratory function. Guillain–Barré syndrome is treated with IVIG or plasmapheresis-not steroids. Myasthenic crisis may require plasmapheresis or IVIG; avoid medications that worsen neuromuscular transmission, such as aminoglycosides and magnesium.
Trap: withholding intubation because oxygen saturation is normal despite weak cough and rising PaCO2; or missing that pupillary sparing and downward gaze can indicate basilar artery stroke rather than seizure.
Rule of thumb: in convulsive status, do not wait for EEG or imaging before giving benzodiazepines.