| Written by Dr.Md.Redwanul Huq (Masum) |
| Monday, 16 January 2012 13:00 |
Seizure:
Definition:
Seizure is a clinical event where there is excessive and synchronous electrical discharge of cerebral neurons which is manifested as motor, sensory, autonomic or psychiatric phenomenon.
Epilepsy:
Definition:
Epilepsy is a condition which is characterized by recurrent seizures of a particular pattern that is unprovoked by any immediate known cause.
Convulsion:
Definition:
Motor activities of seizure are known as convulsion.
Causes of seizures (by age):
1) In cases of neonates and early infants-
a) Metabolic disorders
b) Developmental disorder
c) Hypoxic-ischemic encephalopathy
d) Maternal drug abuse
e) Head injury
f) Viral encephalitis or other CNS infections
g) Tumors of CNS
2) In cases of late infants and early childhood ages-
a) Febrile seizures
b) Genetic epilepsy syndromes
3) In cases of adolescence and early adulthood ages-
a) Head injury
b) CNS lesions (acquired)
c) CNS infections
d) Tumors of CNS
e) Alcohol withdrawal
f) Congenital anomalies of CNS
4) In cases of older adults-
a) CVD (Cerebrovascular disease)
b) Metabolic disturbances
c) Subdural hematoma or other head trauma
d) Tumors of CNS
e)Degenerative diseases.
5) Drugs and other substances that can cause seizures:
I) Anesthetics and analgesics
a) Tramadol
b) Meperidine
c) Local anesthetic agents
II) Antimicrobial drugs / antiviral drugs-
a) Quinolones
b) Beta-lactams
c) Acyclovir
d) Isoniazid
III) Psychotropic agents
a) Antipsychotics
b) Antidepressants
c) Lithium
IV) Immunomodulatory drugs
a) Tacrolimus
b) Cyclosporine
c) Interferons
V) Drugs of abuse
a) Cocaine
b) Phencyclidine
c) Amphetamines
VI) Sedative-hypnotic drug withdrawal
a) Barbiturates
b) Benzodiazepines
c) Alcohol
VII) Other drugs-Radiographic contrast agents, Theophylline, Flumazenil.
Classification of seizures with their clinical features and drugs used for treatment:
| Type of seizures | Clinical features | Consciousness | Duration | Drugs used for treatment | |
| Primary choice | Alternate choice | ||||
| 1. Partial seizures | Carbamazepine, Phenytoin,Sodium valproate | Phenobarbital,Lamotrigine,Gabapentin,Levetiracetam,
Tiagabine, Zonisamide, Oxcarbazepine, Topiramate, Lacosamide, Rufinamide |
|||
| 1.a. Simple partial | Contraction of specific muscle groups, tingling, hot or cold sensations, speech disturbances | Retained | 20 – 60 seconds | ||
| 1.b. Complex partial | Confused behavior, amnesia, dreamy condition,purposeless movements of limbs or parts of limbs | Impaired | 30 seconds-2 minutes | ||
| 1.c. Partial seizure with secondary generalized | Partial seizure progresses into loss ofconsciousness, rigid extension of the trunk and limbs (known as tonic) and thenrhythmic contraction of the arms and legs (known as clonic) | Lost | 1 – 2 minutes | ||
| 2.Generalized seizures | |||||
| 2.a. Absence (petit mal) | Sudden short onset of impaired consciousness, stoppage ofall activities and watching | Impaired | Less than 30 seconds | Ethosuximide | Sodium valproate,Lamotrigine,Clonazepam |
| 2.b. Generalized Tonic-Clonic (grand mal) | Loss of consciousness, huge contraction of skeletal muscles,rigid extension of the trunk and limbs (known as tonic, this posture is calledopisthotonos) and then rhythmic contraction of the arms and legs (known as clonic). | Lost | 1 – 5 minutes | Sodium valproate, Carbamazepine, Phenytoin | Phenobarbital,Lamotrigine,Primidone,Topiramate |
| 2.c. Myoclonic | Sudden, short contraction of limb muscles or whole body | Retained | 1 – 5 seconds | Sodium valproate | Clonazepam,Lamotrigine |
| 2.d. Atonic | Abrupt loss of postural tonicity leading to drooping of the head orfalling | Lost | 5 sec – few minutes | Sodium valproate | |
| 2.e. Tonic | Rigid extension of the trunk and limbs | ||||
| 2.f. Clonic | Rhythmic contraction of the arms and legs | ||||
| 2.g. Infantile spasm | Contraction of limbs or trunk muscles of infants | ||||
| 3. Unclassified seizures | |||||
