Status epilepticus and cluster seizures.

Status epilepticus (SE) is a medical emergency for companion animals, with significant associated morbidity and mortality. Therapy in companion animals and people has been largely with sedatives and anesthetics, many of which have gamma-aminobutyric acid receptor-mediated mechanisms. Early aggressive treatment includes staged first-line therapy with benzodiazepines, and second- and third-line protocols when needed. Recently, intravenous levetiracetam has also been used in for SE in dogs and people, and there are other human intravenous drug preparations that may hold promise for future use in companion animals.

Epileptogenesis and companion animals.

Epileptogenesis is the process by which a normal brain develops into an epileptic brain. There are 3 distinct phases of epileptogenesis-the latent period before seizures occur, the occurrence of recurrent seizures, and in about 30% of patients, the development of refractory epilepsy. Understanding the basic epileptic circuit abnormalities associated with recurrent seizures via aberrations in glutamate, gamma-aminobutyric acid, and ligand- and voltage-gated ion channel activity can help the small-animal practitioner understand the mechanism of action of the antiepileptic drugs currently used for dogs and cats for new-onset and refractory epilepsy. Understanding the latest research results and theories about the pathophysiology of the latent period of epileptogenesis, where recurrent seizures have not yet developed, would help the practitioner understand possible target areas for future treatments to treat epilepsy by preventing it rather than just symptomatically preventing recurrent seizures. The current areas of focus of research on the latent period include neurodegeneration, neurogenesis, axonal sprouting, glial cell activation, invasion of inflammatory cells, angiogenesis, and subclinical alteration of ligand- and receptor-gated ion channels.

Evaluations of labrador retrievers with exercise-induced collapse, including response to a standardized strenuous exercise protocol.

Clinical and metabolic variables were evaluated in 14 Labrador retrievers with exercise-induced collapse (EIC) before, during, and following completion of a standardized strenuous exercise protocol. Findings were compared with previously reported variables from 14 normal Labrador retrievers that participated in the same protocol. Ten of 14 dogs with EIC developed an abnormal gait during evaluation, and these dogs were significantly more tachycardic and had a more severe respiratory alkalosis after exercise compared to the normal dogs. Muscle biopsy characteristics and sequential lactate and pyruvate concentrations were normal. Genetic testing and linkage analysis excluded malignant hyperthermia as the cause of EIC. Common causes of exercise intolerance were eliminated, but the cause of collapse in EIC was not determined.

Exercise-induced collapse of Labrador retrievers: survey results and preliminary investigation of heritability.

Completed surveys were obtained from owners of 225 Labrador retrievers affected by the syndrome of exercise-induced collapse. Questions addressed signalment, age of onset, description of collapse episodes, and owner perception of activities and factors associated with collapse. Most dogs were young (mean 12 months) when collapse episodes began. Retrieving was the activity most commonly associated with collapse. Owners felt that excitement (187/225; 83%) and high environmental temperatures (71/225; 31%) increased the likelihood of collapse. Analysis of pedigrees collected from 169 affected dogs was most consistent with an autosomal recessive mode of inheritance.