Epilepsy and Seizure Disorders: Status epilepticus

• Epilepsy is a chronic neurological disorder that affects the brain. It is characterized by recurrent unprovoked seizures that result from abnormal synchronous electrical activity of a group of neurons in the brain

 

Epileptic seizures

• Seizures are transient episodes of altered consciousness, behavior, sensation, motor activity, or autonomic function that result from abnormal electrical activity of a group of neurons in the brain
• Seizures can be classified into two main types: focal (partial) seizures and generalized seizures
  • Focal seizures: Seizures that originate from a specific region of the brain and affect only one hemisphere. They can be further divided into:
    • Focal aware seizures: Seizures that do not impair consciousness or awareness. They may cause motor symptoms (e.g., twitching, jerking, stiffening), sensory symptoms (e.g., tingling, numbness, flashing lights), autonomic symptoms (e.g., sweating, flushing, palpitations), or psychic symptoms (e.g., deja vu, fear, joy)
    • Focal impaired awareness seizures: Seizures that impair consciousness or awareness. They may cause automatisms (e.g., lip smacking, fumbling, wandering), confusion, amnesia, or postictal (after seizure) symptoms (e.g., headache, fatigue, weakness)
  • Generalized seizures: Seizures that involve both hemispheres of the brain and affect the whole body. They can be further divided into:
    • Absence seizures: Seizures that cause brief lapses of consciousness or awareness. They may cause staring, blinking, or subtle movements
    • Myoclonic seizures: Seizures that cause sudden brief muscle contractions or jerks. They may affect one or more limbs or the whole body
    • Atonic seizures: Seizures that cause sudden loss of muscle tone or strength. They may cause falls or head drops
    • Tonic seizures: Seizures that cause sudden increase of muscle tone or stiffness. They may cause rigid posture or extension of limbs
    • Clonic seizures: Seizures that cause rhythmic muscle contractions or spasms. They may affect one or more limbs or the whole body
    • Tonic-clonic seizures: Seizures that cause a combination of tonic and clonic phases. They may cause loss of consciousness, convulsions, biting of tongue, incontinence, etc.



 

 

Causes of epilepsy and seizure disorders  

•  The causes of epilepsy and seizure disorders vary depending on the type and origin of the seizures.
• some common causes include
  • genetic factors (e.g., mutations or syndromes),
  • structural factors (e.g., trauma, stroke, tumor, infection),
  • metabolic factors (e.g., electrolyte imbalance, hypoglycemia, hypoxia),
  •  immune factors (e.g., autoimmune diseases, inflammation),
  • pharmacological factors (e.g., drug withdrawal, drug toxicity),
  • idiopathic factors (e.g., unknown causes)

 

Risk factors of epilepsy and seizure disorders  

• Some factors that may increase the risk of developing epilepsy and seizure disorders include
  • age (infants and older adults),
  • sex (male),
  •  family history,
  • head injury,
  • brain infection (e.g., meningitis, encephalitis),
  • brain tumor,
  • stroke,
  • dementia, etc.

 

Signs and symptoms of epilepsy and seizure disorders  

• The signs and symptoms of epilepsy and seizure disorders vary depending on the type and severity of the seizures.
• Some common manifestations include
  • altered consciousness, behavior, sensation, motor activity, or autonomic function as described above;
  • aura (a warning sign before a seizure such as a smell, sound, or feeling);
  • prodrome (a mood or physical change before a seizure such as irritability, anxiety, or headache);
  • postictal state (a recovery period after a seizure such as confusion, drowsiness, or weakness);
  • status epilepticus (a prolonged or recurrent seizure that lasts more than 5 minutes or does not stop without treatment)



 

 

Diagnosis of epilepsy and seizure disorders  

• The diagnosis of epilepsy and seizure disorders is based on clinical criteria that include medical history, physical examination, neurological examination, and exclusion of other possible causes.
• Some diagnostic tests that may be used to confirm the diagnosis or identify the type and origin of the seizures include:
  • Electroencephalography (EEG): To measure the electrical activity of the brain using electrodes attached to the scalp that may show abnormal patterns or spikes that indicate seizure activity
  • Neuroimaging: To visualize the structure and function of the brain using techniques such as CT, MRI, PET, SPECT, etc. that may show structural abnormalities or lesions that cause seizures
  • Blood tests: To check for metabolic disorders, infection, inflammation, drug levels, etc. that may cause or mimic seizures
  • Lumbar puncture: To obtain a sample of CSF for analysis and culture that may show infection, inflammation, or bleeding that cause seizures



 

Treatment of epilepsy and seizure disorders  

• The treatment of epilepsy and seizure disorders is aimed at controlling the seizures, reducing the side effects, improving the quality of life, and providing support and education for the patient and caregivers.
• Some treatment options include:
  • Antiepileptic drugs (AEDs): To prevent or reduce the frequency and severity of seizures using drugs such as phenytoin, carbamazepine, valproic acid, lamotrigine, levetiracetam, etc. that act on various neurotransmitter systems or receptors to stabilize the electrical activity of the brain. These drugs may have side effects such as drowsiness, dizziness, rash, liver toxicity, etc.
  • Surgery: To remove or disconnect the brain tissue that causes seizures using procedures such as lobectomy (removal of a lobe of the brain), hemispherectomy (removal of a hemisphere of the brain), corpus callosotomy (cutting of the corpus callosum that connects the two hemispheres of the brain), etc. These procedures may have risks such as infection, bleeding, stroke, cognitive impairment, etc.
  • Neuromodulation: To stimulate or inhibit specific brain regions or nerves using devices such as vagus nerve stimulator (VNS), responsive neurostimulation (RNS), deep brain stimulation (DBS), transcranial magnetic stimulation (TMS), etc. that deliver electrical currents or magnetic fields to modulate neuronal activity. These devices may have side effects such as infection, bleeding, headache, voice changes, etc.
  • Dietary therapy: To modify the intake of carbohydrates, fats, and proteins using diets such as ketogenic diet, modified Atkins diet, low glycemic index treatment, etc. that induce ketosis (a metabolic state that uses fat as the main source of energy) that may reduce seizure activity. These diets may have side effects such as weight loss, constipation, kidney stones, etc.
  • Lifestyle therapy: To avoid or reduce triggers or factors that may provoke seizures using interventions such as stress management, sleep hygiene, exercise, etc. that involve coping with stress, getting enough sleep, performing physical activities, etc. These interventions may improve mood, energy, and well-being in epilepsy and seizure disorder patients

Treatment of epilepsy and seizure disorders  

• The prevention of epilepsy and seizure disorders depends on the type and cause of the seizures.
• Some preventive measures include:

 

• • avoiding head injury, infection, stroke, tumor, etc. that may damage the brain
  • avoiding drugs, alcohol, caffeine, etc. that may alter the brain chemistry
  • avoiding flashing lights, loud noises, etc. that may stimulate the brain
  • taking AEDs as prescribed
  • following a healthy lifestyle
  • seeking medical attention if experiencing any signs or symptoms of seizures

Status epilepticus.

• The nervous system consists of the central nervous system (CNS) and the peripheral nervous system (PNS)
• The CNS includes the brain and the spinal cord, which are responsible for processing and integrating sensory and motor information
• The PNS includes the cranial and spinal nerves, which connect the CNS to the rest of the body
• The nervous system communicates through electrical impulses and chemical signals called neurotransmitters
• A seizure is a sudden, abnormal, and excessive discharge of neurons in the brain that causes a change in behavior, sensation, or consciousness
• Status epilepticus (SE) is a neurologic emergency that occurs when a seizure lasts longer than 5 minutes or when seizures occur very close together without recovery between them
• SE can be classified into two main types: generalized convulsive SE (GCSE) and nonconvulsive SE (NCSE)
• GCSE is characterized by repeated tonic-clonic seizures that involve both hemispheres of the brain and cause loss of consciousness, muscle contractions, and rhythmic jerking of the extremities
• NCSE is characterized by continuous or fluctuating altered mental status or behavior without overt motor manifestations
• SE can cause permanent brain damage or death if not treated promptly and effectively



Causes and risk factors of Status epilepticus.

• SE can be caused by various factors that trigger or exacerbate seizures, such as:
  • Acute or chronic CNS disorders, such as stroke, trauma, infection, tumor, malformation, degeneration, or inflammation
  • Metabolic disturbances, such as hypoglycemia, hyponatremia, hypocalcemia, hypomagnesemia, uremia, hepatic encephalopathy, or acidosis
  • Drug toxicity or withdrawal, such as from alcohol, benzodiazepines, barbiturates, opioids, anticonvulsants, or illicit substances
  • Acute or chronic systemic illnesses, such as sepsis, fever, hypoxia, hypotension, anemia, or electrolyte imbalance
  • Genetic or idiopathic epilepsy syndromes, such as Dravet syndrome, Lennox-Gastaut syndrome, or febrile seizures
• The risk factors for SE vary depending on the age group and the underlying etiology of seizures
• In general, some risk factors include:
  • History of epilepsy or previous seizures
  • Nonadherence or subtherapeutic levels of anticonvulsant therapy
  • African American race
  • Male gender
  • Low socioeconomic status
  • Comorbidities that affect the CNS or metabolism

 

Pathophysiology of Status epilepticus.

• SE occurs when the normal mechanisms that terminate a seizure fail to function properly
• This results in a mismatch of excitatory and inhibitory neurotransmitters in the brain, such as glutamate and gamma-aminobutyric acid (GABA)
• Glutamate is the main excitatory neurotransmitter that stimulates neuronal activity and increases calcium influx into neurons
• GABA is the main inhibitory neurotransmitter that reduces neuronal activity and increases chloride influx into neurons
• In SE, there is an excessive release of glutamate and a reduced release of GABA, leading to neuronal hyperexcitability and hypersynchronization
• SE can be divided into two phases: phase I and phase II
• Phase I occurs in the first 30 minutes of seizure activity and is characterized by increased autonomic activity and cerebral blood flow
• Each seizure causes a sharp increase in epinephrine, norepinephrine, and steroid concentrations that cause hypertension, tachycardia, cardiac arrhythmias, hyperglycemia, hyperthermia, sweating, and salivation
• Cerebral blood flow is increased to meet the increased metabolic demand of the brain during seizures
• Increased sympathetic and parasympathetic stimulation with muscle hypoxia can lead to ventricular arrhythmias, severe acidosis, and rhabdomyolysis (breakdown of muscle tissue)
• Shock, hypotension, hyperkalemia, and acute tubular necrosis may occur as a result of prolonged muscle contractions and tissue damage
• Phase II occurs after 30 minutes of seizure activity and is characterized by loss of cerebral autoregulation, decreased cerebral blood flow, increased intracranial pressure, and systemic hypotension
• The body is no longer able to compensate for the increased metabolic demand of the brain and the seizures become self-sustaining
• Hypoglycemia, hyperthermia, respiratory failure, hypoxia, respiratory and metabolic acidosis, hyperkalemia, hyponatremia, and uremia may develop as a result of impaired organ function and homeostasis
• The prolonged and recurrent seizures can cause neuronal injury and death through various mechanisms, such as:
  • Excitotoxicity, which is the excessive stimulation of neurons by glutamate that leads to calcium overload and oxidative stress
  • Apoptosis, which is the programmed cell death that is triggered by mitochondrial dysfunction and DNA damage
  • Necrosis, which is the uncontrolled cell death that is caused by energy depletion and membrane disruption
  • Inflammation, which is the activation of immune cells and cytokines that cause further neuronal damage and edema
• The neuronal injury and death can result in permanent brain damage or death, depending on the extent and location of the affected brain regions

 

Clinical manifestation of Status epilepticus.

• The clinical manifestations of SE depend on the type, duration, and severity of seizures, as well as the underlying etiology and comorbidities of the patient
• In general, some common signs and symptoms include:
  • Altered level of consciousness, ranging from confusion to coma
  • Motor manifestations, such as tonic-clonic movements, myoclonus, focal seizures, or subtle twitching
  • Autonomic manifestations, such as hypertension, tachycardia, cardiac arrhythmias, hyperthermia, sweating, salivation, or incontinence
  • Neurologic manifestations, such as headache, visual disturbances, aphasia, hemiparesis, or focal deficits
  • Metabolic manifestations, such as hypoglycemia, hyponatremia, hyperkalemia, acidosis, or uremia
  • Respiratory manifestations, such as hypoxia, hypercapnia, respiratory failure, or pulmonary edema
  • Musculoskeletal manifestations, such as rhabdomyolysis, muscle breakdown, or compartment syndrome

Diagnosis of Status epilepticus.

• The diagnosis of SE is based on the clinical history and presentation of the patient, as well as the results of laboratory and imaging tests
• The diagnosis requires a high index of suspicion and prompt recognition of seizure activity and its duration
• The diagnosis can be confirmed by electroencephalography (EEG), which is the gold standard for detecting seizure activity in the brain
• EEG can also help to differentiate between GCSE and NCSE, as well as to identify the seizure focus and etiology
• EEG should be performed as soon as possible after the onset of SE or after the administration of initial anticonvulsant therapy
• Other diagnostic tests that may be performed include:
  • Blood tests to measure glucose, electrolytes, calcium, magnesium, liver function tests, renal function tests, blood cultures, arterial blood gas, and serum anticonvulsant levels
  • Urine tests to screen for drugs or toxins that may cause or worsen seizures
  • Lumbar puncture to obtain cerebrospinal fluid (CSF) for analysis and culture to rule out CNS infection or inflammation
  • Computed tomography (CT) scan or magnetic resonance imaging (MRI) of the brain to detect structural lesions or abnormalities that may cause or result from seizures

Treatment of Status epilepticus.

• The treatment of SE aims to stop the seizures as quickly and safely as possible, to identify and treat the underlying cause, and to prevent complications and recurrence
• The treatment involves a stepwise approach that consists of three stages: initial stabilization, initial therapy, and refractory therapy
• Initial stabilization involves securing the airway, breathing, and circulation (ABCs) of the patient, as well as monitoring vital signs, oxygen saturation, and glucose levels
• Initial therapy involves administering intravenous benzodiazepines, such as lorazepam or diazepam, as first-line anticonvulsants to terminate the seizures within 5 minutes of administration
• Refractory therapy involves administering intravenous non-benzodiazepine anticonvulsants, such as phenytoin, fosphenytoin, valproate, levetiracetam, or lacosamide, as second-line anticonvulsants to prevent seizure recurrence within 60 minutes of administration
• If seizures persist despite initial and refractory therapy, the patient is considered to have super-refractory SE and may require more aggressive treatment options, such as continuous infusion of anesthetic agents (e.g. propofol), ketamine, or barbiturates (e.g. pentobarbital), or other interventions such as hypothermia or surgery

Nursing care and management of Status epilepticus.

• The nursing care and management of patients with SE involves:
  • Providing a safe and supportive environment for the patient, such as padding the bed rails, removing any potential hazards, maintaining a patent airway, administering oxygen, and suctioning secretions as needed
  • Administering anticonvulsant medications as prescribed and monitoring their effectiveness and adverse effects, such as respiratory depression, hypotension, sedation, or allergic reactions
  • Monitoring the patient’s vital signs, neurologic status, seizure activity, and EEG findings, and reporting any changes or abnormalities to the health care provider
  • Performing frequent blood tests to assess glucose, electrolytes, calcium, magnesium, liver function, renal function, blood cultures, arterial blood gas, and serum anticonvulsant levels, and correcting any imbalances or abnormalities as ordered
  • Providing adequate hydration and nutrition to the patient, either orally or parenterally, and preventing aspiration or dehydration
  • Preventing complications such as infection, pressure ulcers, contractures, or venous thromboembolism by implementing appropriate measures such as hygiene, skin care, passive range of motion exercises, and prophylactic anticoagulation
  • Educating the patient and family about the causes, signs and symptoms, treatment, and prevention of SE and seizures in general, as well as the importance of adherence to anticonvulsant therapy and regular follow-up visits
  • Providing emotional support and reassurance to the patient and family and addressing any concerns or fears they may have

Complications and outcomes of Status epilepticus.

• SE is a life-threatening condition that can cause serious complications and poor outcomes if not treated promptly and effectively
• Some of the possible complications include:
  • Permanent brain damage or death due to neuronal injury or death, cerebral edema, increased intracranial pressure, or cerebral ischemia
  • Respiratory failure or pulmonary edema due to hypoxia, hypercapnia, or aspiration
  • Cardiac arrest or arrhythmias due to autonomic instability, hypotension, or electrolyte imbalance
  • Shock or multiorgan failure due to hypoperfusion, acidosis, or rhabdomyolysis
  • Infection or sepsis due to impaired immunity, invasive procedures, or catheter-associated complications
• The outcomes of SE depend on various factors such as the type, duration, and severity of seizures, the underlying etiology and comorbidities of the patient, and the timeliness and effectiveness of treatment
• Some of the possible outcomes include:
  • Complete recovery without any residual neurologic deficits or recurrence of seizures
  • Partial recovery with some degree of neurologic impairment or increased frequency or severity of seizures
  • Persistent vegetative state or coma due to extensive brain damage or anoxic injury
  • Death due to refractory seizures or complications