Fever in ICU Patients: Clinical Challenges and Management
Abstract
Background: Fever is a common and clinically significant finding in intensive care units (ICUs), often signaling infection but also arising from diverse non-infectious etiologies. Its interpretation is complex due to critical illness physiology, invasive interventions, and immune variability.
Aim: To review the definitions, epidemiology, pathophysiology, diagnostic approach, and management strategies for fever in critically ill patients, emphasizing evidence-based practices and context-specific considerations.
Methods: A comprehensive narrative review of current guidelines and major epidemiologic studies was conducted, integrating data on fever thresholds, etiologic patterns, diagnostic algorithms, and therapeutic interventions in ICU settings.
Results: Fever occurs in 26–88% of ICU patients, with sepsis accounting for approximately 63% of cases. Infectious causes include ventilator-associated pneumonia, catheter-related bloodstream infections, and intra-abdominal infections, while non-infectious sources range from drug fever to thromboembolic disease and endocrine crises. High-grade fever (>39.5°C) correlates with increased mortality, particularly in non-septic patients. Diagnostic evaluation requires systematic history, physical examination, microbiologic sampling, biomarker interpretation, and imaging. Management prioritizes early antimicrobial therapy, source control, and individualized temperature regulation. Evidence does not support routine aggressive fever suppression except in neurologic injury or extreme hyperthermia.
Conclusion: Fever in ICU patients is a multifactorial phenomenon requiring disciplined evaluation and tailored management. Over-reliance on fever as an infection surrogate risks unnecessary antibiotic use and missed alternative diagnoses. Optimal care integrates rapid infection control, judicious antipyresis, and multidisciplinary collaboration.
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Copyright (c) 2025 Nazeeh Omar Alsahafi, Sultan Eid Alahmadi, Ahmed S ALjohani, Majed Awad Alzahrani, Faisal Talal Alradadi, Ali Mohammed Aljohani, Abdullah Mohammed Alzahrani, Rasha Tariq Abduljwad, Fahad Abdullah Nasir Alotibi
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