Associations between fever following hemispherotomy, surgeon experience, and increased CSF protein

Fever following hemispheric disconnection surgery is a well-known, although poorly understood, phenomenon resulting in frequent infectious workups. Prior studies have identified univariate relationships between post-hemispherotomy fever, seizure etiology, and use of an external ventricular drain for temporary CSF diversion. The aim of this study was to examine multivariate relationships between the occurrence of post-hemispherotomy fever, clinical characteristics, and CSF parameters.

A retrospective chart review was conducted for all patients who underwent hemispherotomy performed by a single surgeon at the Children's Hospital of Philadelphia from May 2017 to July 2024. Clinical characteristics, including seizure etiology, operative duration, estimated blood loss, age and weight at the time of surgery, and case chronology (i.e., surgeon experience) were abstracted. The daily maximum temperature (Tmax), antipyretic medication dosages, steroid regimen, and all blood and CSF laboratory values were recorded. Fever was defined as Tmax > 38.5°C on postoperative days 0-14. Associations between postoperative fever, clinical characteristics, and CSF parameters were assessed via multivariate logistic regression analysis.

Seventy patients (35 male and 35 female, mean age 7.2 years) were included in the analysis. Postoperative fever occurred in 30 patients (42.9%). Fever was more common among patients with Rasmussen's encephalitis (RE; 8/11, 72.7%) and hemimegalencephaly (HME; 5/9, 55.6%), although neither etiology was significant in the multivariate analysis (p = 0.069 and p = 0.097, respectively). Fevers occurred more frequently at the beginning of the surgeon's career and declined with case chronology (OR 0.96, p = 0.047). Among patients for whom CSF laboratory testing was performed (52/70, 74.3%), a significant association was observed between the CSF protein level and postoperative fever (OR 1.002, p = 0.045).

The likelihood of fever following hemispherotomy declined with surgeon experience and was positively associated with an elevated CSF protein level. Fevers might also be more common in patients with certain seizure etiologies, specifically RE and HME.