In my last post, I discussed seizures and I will be continuing this topic in this post. We discussed the causes and triggers of seizures which are; Vascular Causes, Infectious Causes, Traumatic Causes, Autoimmune Causes, Metabolic Causes, Idiopathic Causes, Neoplasia causes, Drug causes, and Eclampsia Causes. This makes the Mnemonic VITAMIN D and E. In the previous post, I explained the Pathophysiology of Seizures, and I started with the Clinical Features of Seizures where I looked into Focal Seizures. Today, I will continue with seizures, explaining the Clinical Features of Seizures, Generalized seizures, the areas where the generalized seizures present, Diagnosis, treatment, and Epilepticus. Sit back and enjoy the post.
Clinical Features of Seizures Continued
Focal Sensory seizures cause patients to feel pain and paresthesias, if the electric activity is abnormal in the occipital lobe it could affect the Primary visual cortex, and patients could experience visual hallucinations. In the temporal lobe (primary auditory cortex), it could cause patients to hear abnormal sounds. In the primary olfactory cortex, patients would start to smell things that aren't there (abnormal smell). The gustatory cortex which is responsible for taste starts to allow the patient to have an abnormal taste (metallic taste). ,
Focal autonomic seizure patients suffer seizures in the Insula (which regulates autonomic activities). patients with focal autonomic seizures would experience increased cardiac activities (heart rate causing tachycardia, and blood pressure causing hypertension). Since it is autonomic, the bladder system could be affected, leading to Urinary incontinence, and also affect salivation in the mouth, and sweating. ,. The Temporal Lobe, which controls the limbic system that deals with emotions, and behaviors, seizures will cause people to exhibit emotional behaviors such as hypersexual behavior, Deja Vu, derealization, and depersonalization..
Focal Seizure with Impairment or Without Impairment
Impairment has to do with the loss of consciousness, and it is important to know if the seizure is associated with the brain and brainstem. If the focal seizure has involvement with the reticular formation (which is the arousal system), the Thalamus, leading to patients experiencing aura, Todd's paralysis, and Post-ictal state, then the seizure can lead to loss of cautiousness (impairment). Focal seizure without impairment doesn't involve the thalamus and the reticular formation. The focal seizure happens in the cerebral hemisphere without hitting these regions. ,,.
It is important to know that focal seizure with impairment can lead to generalized seizures. When the seizure begins at one hemisphere, involving the thalamus, and the reticular formation, it can still be regarded as a focal seizure, but when it goes into another hemisphere passing through the corpus callosum, with history of aura, automatism, afterwords, it is a focal seizure that became a generalized seizure. ,.
Generalized Seizures
Generalized seizures have to do with a generalized hemisphere involvement, affecting the thalamus, the reticular formation, and a post-ictal state after the seizure, then it is a generalized seizure. Generalized seizures can be divided into two types which are motor and non-motor seizures.
Generalized motor seizure can present in various forms which include Generalized-Atonic Seizures, generalized-clonic seizures, Generalized-tonic seizures, generalized-myoclonic seizures, and Tonic-Clonic seizures. Tonic-Clonic Seizure usually causes convulsion, stiffening, and movement of bilateral movement of upper limbs, lower limbs, and the muscles of the respiratory system. Leading to a cry or involuntary scream, causing an upper movement of the eyes/upgaze of the eye, it also pulls oral secretion, intended contraction of the mastic muscle tightening the teeth really hard, it also causes the release of the sphincter in the urethra and the anal sphincter area, leading to incontinence. Tonic-Clonic seizure can also increase the action potentials of the heart, causing an increased heart rate, and blood pressure. It is also accompanied by post-ictal phases with amnesia, confusion, and lethargy.,,
Generalized Non-motor Seizure is classified as Absence seizures. With the absence seizures, patients could experience blackout and daydreaming effects. It causes automatism, but generalized non-motor Seizures do not cause loss of muscle tone, and they do not possess any postictal state. ,
Diagnosis for Seizures
If patients with seizure have a history of seizure or are epileptic, then there is a possibility that they are on an anti-epileptic medication, so it is important to check the AED level. If the AED level is low, then the dosage is increased to get into the therapeutic range. If the AED level is normal, then the drug should be switched to another anti-epileptic drug. If there is an underlying cause of seizures, it is important to check the underlying cause.,. If the patient doesn't have a history of seizure, it is important to know why the patient seized and what triggered the seizure, looking through the Vitamin D and E mnemonic. If it is a vascular seizure, it could be caused by ischemic stroke, subarachnoid hemorrhage, intracerebral hemorrhage, anoxic brain injury, prez posterior reversal encephalopathy, and intracerebral hemorrhage. A CT, MRI, Lumber Puncture for Subarachnoid hemorrhage can be done, EEG. In the case of infectious triggers as well, CT, MRI, Lumber puncture, Blood Cultures, CBC, ,,.
Treatments for Seizures
When a patient seizes, they are treated with anti-epileptics depending on whether they have a history of seizures. it is important to check for the underlying cause of the seizure based on diagnostics. If the cause is reversible, it is important to treat the underlying cause but if the cause isn't reversible easily, then it is important to keep treating with anti-epileptic drugs until the cause has been treated. It is important to know that seizure is a symptom of an underlying disorder resulting from any of the VITAMIN D and E mnemonic causing abnormal electric activities in the brain. Remember that seizures are a result of an increase in the glutamate pathway, and a decrease in the inhibitory GABA pathway. Anti-Epileptic drugs would either increase the inhibitory GABA pathway or decrease the glutamate pathway. Drugs that block sodium channels to decrease glutamate are Valproic acid (Valproate), Phenytoin, Topiramate, Lamotrigine, carbamazepine, and Fosphenytoin. . Other drugs that increase the inhibitory GABA pathway are Gabapentin, Ethosuximide (for treating Absence seizures). SV2A blockers include Levetiracetam (with the brand name Keppra or Nayzilam). Anti-Epileptic drug that target the NMDA receptors blocking glutamate from binding to the receptors is ketamine . Drugs that increase the GABA pathway are Benzodiazepines which include Lorazepam, Diazepam, and Midazolam. Other drugs are propofol, and phenobarbital.,
Image Reference
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