Incidence, risk factors, and outcomes for early postoperative seizures in dogs with rostrotentorial brain tumors after intracranial surgery

• Published in: Journal of veterinary internal medicine Vol. 36; no. 2; pp. 694 - 701
• Main Authors: Parker, Rell L., Du, John, Shinn, Richard L., Drury, Adam G., Hsu, Fang‐Chi, Roberston, John L., Cecere, Thomas E., Arendse, Avril U., Rossmeisl, John H.
• Format: Journal Article
• Language: English
• Published: Hoboken, USA John Wiley & Sons, Inc 01-03-2022; Wiley
• Subjects: Animals; brain biopsy; Brain cancer; Brain Neoplasms - complications; Brain Neoplasms - surgery; Brain Neoplasms - veterinary; canine; craniotomy; Dog Diseases - epidemiology; Dog Diseases - pathology; Dog Diseases - surgery; Dogs; Humans; Incidence; intracranial neoplasm; Medical records; neurosurgery; Postoperative Complications - veterinary; Postoperative Period; Retrospective Studies; Risk Factors; Seizures - epidemiology; Seizures - etiology; Seizures - veterinary; SMALL ANIMAL; Tumors; canine; intracranial neoplasm; neurosurgery; brain biopsy; craniotomy
• ISSN: 0891-6640; 1939-1676
• DOI: 10.1111/jvim.16391

Background
Seizures in the early postoperative period after intracranial surgery may affect outcome in dogs.
Objectives
To determine the incidence of early postoperative seizures (EPS) in dogs with brain tumors, identify specific risk factors for EPS, and determine if EPS affects outcome.
Animals
Eighty‐eight dogs that underwent 125 intracranial surgeries for diagnosis and treatment of rostrotentorial brain tumors.
Methods
Retrospective cohort study. All patients with a diagnosis of rostrotentorial brain tumor from 2006 to 2020 were included. Early postoperative seizures were diagnosed by observation of seizure activity within 14 days of neurosurgery. Previously diagnosed structural epilepsy, perioperative anticonvulsant drug (ACD) use, magnetic resonance imaging (MRI), and tumor characteristics were evaluated. Outcome measures included neurologic and nonneurologic complications, duration of hospitalization, and survival to discharge.
Results
Dogs with rostrotentorial brain tumors had EPS after 16/125 (12.8%) neurosurgical procedures (95% confidence interval [CI], 7%‐19%). Presence of previous structural epilepsy was not associated with EPS risk (P = 1). Perioperative ACD use also was not associated with EPS (P = .06). Dogs with EPS had longer hospitalization (P < .001), were more likely to have neurologic complications postsurgery (P = .01), and were less likely to survive to discharge (P = .01).
Conclusions and Clinical Importance
It is difficult to predict which dogs are at risk of EPS because the presence of previous structural epilepsy and the use of perioperative ACDs was not associated with EPS. However, seizures in the early postoperative period are clinically important because affected dogs had prolonged hospitalization, more neurologic complications, and decreased short‐term survival.