Quiz: Managing Canine & Feline Seizures
Elizabeth Thomovsky, DVM, MS, DACVECC , Purdue University
Seizures are a common neurologic disorder in dogs and cats and therefore common presentations in emergency and general clinics.1 Seizure patients can range from those actively experiencing a seizure (ie, emergent) to those presented following a seizure in the home. Understanding how to manage seizures, including in-clinic diagnostics and anticonvulsant treatments, is important.
A generalized seizure occurs when electrical activity in the cerebral cortex of the brain leads to loss of consciousness, tonic-clonic muscular movements, and spontaneous autonomic functions (eg, urination, defecation).2 A continuous seizure lasting >5 minutes or ≥2 seizures without recovery of consciousness is referred to as status epilepticus.2 Cluster seizures are ≥2 seizures that occur within a 24-hour period.2
CBC & Serum Chemistry Profile Parameters That Can Cause Seizures
Anemia and polycythemia reduce oxygen delivery to cells of the brain due to reduced blood oxygen content (anemia) and reduced delivery of blood to brain cells.
Thrombocytopenia with platelet counts <5,000 to 10,000 cells/μL can result in spontaneous hemorrhage in various places. Occurrence in the forebrain can cause seizures.23
Liver functional failure (demonstrated by hypoalbuminemia, hypocholesterolemia, hypoglycemia, hyperbilirubinemia, and low blood urea nitrogen) causes hepatic encephalopathy, which can result in forebrain signs (eg, seizures).6
Severe azotemia from renal failure can cause uremic encephalopathy that manifests as seizures.6
Extreme changes (ie, elevation, decrease) in sodium levels from normal can alter mentation and lead to seizure-like episodes.6 Although the magnitude of change that leads to neurologic signs depends on the patient, more extreme changes—especially over a short period of time—are more likely to cause a seizure. For example, a serum sodium increase of 40 mmol/L over 6 hours is more likely to lead to neurologic signs than the same increase over 6 days. In addition, rapid correction of sodium levels is more likely to cause seizures when therapy is initiated.6
Tetany from hypocalcemia presents as seizure events.6
Hypoglycemia is a common cause of seizure activity.6
Listen to the Podcast
In this podcast episode, Dr. Thomovsky explains how to triage seizure cases, prioritize diagnostics, and gain short-team control with benzodiazepines.