Constant rate infusion of diazepam or propofol for the management of canine cluster seizures or status epilepticus

Abstract

IntroductionCluster seizures (CS) and status epilepticus (SE) in dogs are severe neurological emergencies that require immediate treatment. Practical guidelines call for constant rate infusion (CRI) of benzodiazepines or propofol (PPF) in patients with seizures not responding to first-line treatment, but to date only few studies have investigated the use of CRI in dogs with epilepsy.Study designRetrospective clinical study.MethodsDogs that received CRI of diazepam (DZP) or PPF for antiepileptic treatment during hospitalization at the Veterinary Teaching Hospital of the University of Turin for CS or SE between September 2016 and December 2019 were eligible for inclusion. Favorable outcome was defined as cessation of clinically visible seizure activity within few minutes from the initiation of the CRI, no seizure recurrence within 24 h after discontinuation of CRI through to hospital discharge, and clinical recovery. Poor outcome was defined as recurrence of seizure activity despite treatment or death in hospital because of recurrent seizures, catastrophic consequences of prolonged seizures or no return to an acceptable neurological and clinical baseline, despite apparent control of seizure activity. Comparisons between the number of patients with favorable outcome and those with poor outcome in relation to type of CRI, seizure etiology, reason for presentation (CS or SE), sex, previous AED therapy and dose of PPF CRI were carried out.ResultsA total of 37 dogs, with 50 instances of hospitalization and CRI administered for CS or SE were included in the study. CRI of diazepam (DZP) or PPF was administered in 29/50 (58%) and in 21/50 (42%) instances of hospitalization, respectively. Idiopathic epilepsy was diagnosed in 21/37 (57%), (13/21 tier I and 8/21 tier II); structural epilepsy was diagnosed in 6/37 (16%) of which 4/6 confirmed and 2/6 suspected. A metabolic or toxic cause of seizure activity was recorded in 7/37 (19%). A total of 38/50 (76%) hospitalizations were noted for CS and 12/50 (24%) for SE. In 30/50 (60%) instances of hospitalization, the patient responded well to CRI with cessation of seizure activity, no recurrence in the 24 h after discontinuation of CRI through to hospital discharge, whereas a poor outcome was recorded for 20/50 (40%) cases (DZP CRI in 12/50 and PPF CRI in 8/50). Comparison between the number of patients with favorable outcome and those with poor outcome in relation to type of CRI, seizure etiology, reason for presentation (CS or SE), sex and previous AED therapy was carried out but no statistically significant differences were found.ConclusionsThe present study is the first to document administration of CRI of DZP or PPF in a large sample of dogs with epilepsy. The medications appeared to be tolerated without major side effects and helped control seizure activity in most patients regardless of seizure etiology. Further studies are needed to evaluate the effects of CRI duration on outcome and complications.

ACVIM Consensus Statement on the management of status epilepticus and cluster seizures in dogs and cats

“…After the exclusion of duplicates, 87 (SE) and 28 (CS) studies remained and entered stage 2 screening. Of these, 38 clinical studies 2,3,37‐40,43‐74 (SE; dogs, n = 36; cats, n = 5) and 12 clinical studies 37,40,48,49,57,64,75‐80 (CS; dogs, n = 12; cats, n = 0) as well as 37 pharmacokinetic studies 49,57,65,81‐114 (dogs, n = 33; cats, n = 4) fulfilled stage 2 criteria and were selected for review. Some clinical studies included a mixed populations of dogs and cats.…”

“…Overall, although the ideal recommendation would be a minimum 24‐hour duration of IV CRI anesthetics based on guidelines used in humans, the panel considered a minimum duration of 12 hours, determined on an individual basis, according to the animal's clinical status and with the aim to decrease risks related to long‐term hospitalization and adverse effects of medications. In a recent study in dogs, however, no superiority of shorter (12 hours) over longer (24 hours) duration of propofol or DZP IV CRI was found regarding the outcome or duration of hospitalization 200 . The panel suggests that, if seizures relapse within a 12‐hour IV CRI duration of anesthetic administration, then a longer duration should be considered in clinically stable patients.…”

“…The most commonly reported form of SE in animals is generalized (tonic-clonic) CSE. 4,[37][38][39][40][41] However, the diagnosis of CSE and, in particular, NCSE can be overlooked in veterinary patients mainly because of the broad lack of utilization of and expertise in ictal EEG. 42 There are only a few reports of the use of EEG for the diagnosis of NCSE.…”

“…In a recent study in dogs, however, no superiority of shorter (12 hours) over longer (24 hours) duration of propofol or DZP IV CRI was found regarding the outcome or duration of hospitalization. 200 The panel suggests that, if seizures relapse within a 12-hour IV CRI duration of anesthetic administration, then a longer duration should be considered in clinically stable patients.…”

“…However, the broad clinical semiology of CSE and NCSE reported in humans has not been observed or officially described in animals. The most commonly reported form of SE in animals is generalized (tonic‐clonic) CSE 4,37‐41 . However, the diagnosis of CSE and, in particular, NCSE can be overlooked in veterinary patients mainly because of the broad lack of utilization of and expertise in ictal EEG 42 .…”