Non-infectious fever in the neurological intensive care unit: incidence, causes and predictors

Abstract

Background and objective: Non-infectious causes of fever are often considered in critical neurological patients but their true significance has not been formally studied. The aim of this study was to evaluate the incidence, causes and predictors of fever in patients with acute neurological/neurosurgical disease and no documented infection.

Methods: Prospective data collection of consecutive patients admitted to the neurological intensive care unit (NICU) of an academic medical centre for more than 48 h was carried out. Fever was defined as body temperature > or = 101 degrees F (38.3 degrees C) documented on at least one measurement for 2 consecutive days. Patients were enrolled only if a diagnostic workup, including cultures of > or = 2 body samples, was performed before antibiotic use. Febrile patients with no proven evidence of infection were considered to have non-infectious fever.

Results: 93 patients were included in the final analysis. Fever was non-infectious in 31 patients (33%). There were no differences between the infectious and non-infectious fever groups in terms of age, use and duration of invasive catheters, daily duration of fever and number of days with fever. Documented infections tended to be more common among febrile patients with traumatic brain injury (52% vs 36%; p = 0.06). Non-infectious fever was more frequent among patients with subarachnoid haemorrhage (48% vs 18%; p = 0.01) in whom it was associated with vasospasm (p = 0.03) and symptomatic vasospasm (p = 0.05). Non-infectious fever started earlier (mean 2.6 vs 4 days; p = 0.007) and onset of fever within the first 72 h of admission predicted negative evaluation for infection (p = 0.01). Subarachnoid haemorrhage and fever onset within the first 72 h were independent predictors of non-infectious fever on multivariable analysis.

Conclusions: Fever in the absence of documented infections occurs commonly in the NICU, especially among patients with subarachnoid haemorrhage and vasospasm. Early onset of fever predicts a non-infectious cause.