There are many types and causes of seizures in veterinary patients and some “seizures” that are not seizures at all.
Episodes, involving the loss of limb function, loss of balance, loss of consciousness, loss of bladder or bowel control, muscle or limb tremors, bowed neck, or recumbent paddling (flailing the limbs while on the ground), usually fall into one of two categories: Seizures, (most often) - a central nervous system event; or syncope, (less often) - a cardiac event.
An ECG measures the electrical impulses across the heart. These impulses are represented by the characteristic wave and “beep” seen and heard from an ECG monitor. This electric wave is intended to produce a heart beat, which in turn should produce a pulse wave of blood throughout the body. When something in the rhythmic system is wrong, waves occur without a responsive pulse. This arrhythmia can cause periods of reduced circulation to the brain and spinal cord and result in spontaneous, inappropriate or incomplete function of the nervous system. Such events can thereby produce symptoms very similar to seizures.
Performing an ECG can often identify the presence and type of arrhythmia causing the event, but some arrhythmias come and go (paroxysmal). For these elusive arrhythmias, 24 hour monitoring may be necessary to find the cause.
Causes of true seizures usually fall into one of five large groups: trauma; toxic; infectious diseases of the brain, spinal cord or their membranes (encephalitis/meningitis); metabolic (liver, kidney, electrolyte disorders, etc.); or primary brain disorders (epilepsy or tumors).
Blood work can help identify (or rule out) problems associated with primary organs, electrolytes and some infections. Additionally, some toxins (like antifreeze) produce characteristic changes in basic blood work. As with humans, an MRI is helpful in evaluation for scars in the brain from trauma or the presence of tumors.
There are no readily available tests for epilepsy. It is often a presumed diagnosis if there is no evidence of any other cause of the event. Epilepsy usually develops as a rhythmic cycle of seizure clusters or period. During this time period, patients may have several seizures, then “cycle out” till the next cluster period. Cluster periods can be separated by days, weeks, months, or years. Seizures that occur while in a cluster period will also often loosely develop a pattern in their number, severity, and length.
Patients that have a few, mild, short seizures, several years apart, will not likely be put on anti-seizure medication. Patients that have many, protracted, severe seizures, several days apart, will be put on medication. Everything in between is a judgement call made based on those parameters.
There are many seizure medications available and each patient reacts a little differently to each medication. Sometimes a little trial and error is necessary to find a program that best fits your pet. Depending on the severity of the event, our doctors will often start immediate IV medication to try and stop existent seizures and recommended appropriate diagnostics and monitoring of your pet to allow better assessment of seizures frequency and intensity.
While your pet is having a siezure, it is imperative that you remain calm. Pets won't understand that your panic is from their seizure and may subsequently presume there is some other cause for panic in the room - thus making their seizure event worse. Do not try to force anything in their mouth - they won't "swallow their tongue" but you will obstruct their airway and may get bitten in the process. Place them on a flat low surface to prevent falling and secure the area so they won't knock things over on themselves.
The presence of one seizure is enough to warrant an immediate visit to our office to get help before the next one comes.
While seizures are an easy thing to get “all shook up over”, we hope that this information helps give you confidence when facing it as a problem with your pet.