Treatment of Central Fever
For patients with central fever, use antipyretic medications (acetaminophen or NSAIDs) as first-line treatment, particularly in neurologically injured patients where fever can precipitate secondary brain injury. 1, 2
Diagnostic Prerequisites Before Treatment
Central fever is a diagnosis of exclusion—you must rule out infectious and other non-infectious causes first 1:
- Obtain chest radiograph for all ICU patients with new fever 1, 3
- Collect at least two sets of blood cultures (60 mL total) before starting any antimicrobials 1, 3
- If central venous catheter present, draw simultaneous central and peripheral blood cultures 1
- Consider CT imaging for patients with recent thoracic, abdominal, or pelvic surgery 1, 3
- Lumbar puncture if neurological symptoms warrant and not contraindicated 1, 2
Pharmacologic Treatment Algorithm
First-Line Therapy
Administer antipyretic medications immediately—do not delay treatment while searching for fever source, as fever duration correlates with worse outcomes in neurologically injured patients 2:
- Acetaminophen as first-line agent 2, 4
- NSAIDs as alternative first-line option 2
- Target temperature: 36.0-37.5°C in patients with stroke or neurological injury 2
Rationale for Pharmacologic Approach
- Antipyretic medications are preferred over non-pharmacologic cooling methods for patients desiring symptomatic relief 1, 3
- Uncontrolled neurogenic fever precipitates secondary brain injury through increased intracranial pressure and metabolic demands 1, 2
- For acute ischemic stroke patients specifically, prompt fever treatment prevents worse outcomes 1
Refractory Cases
If standard antipyretics fail, consider off-label agents based on case report evidence 5:
- Bromocriptine (dopamine agonist)
- Propranolol (beta-blocker)
- Baclofen (GABA agonist)
Note: These medications have only anecdotal support from case reports with significant heterogeneity in dosing and duration 5
Advanced Temperature Control
For severe refractory fever 2:
- Utilize automated feedback-controlled temperature management devices
- Maintain temperature variation ≤±0.5°C per hour, ≤1°C per 24 hours to avoid complications
Temperature Monitoring Strategy
Use central temperature monitoring methods when available 1, 3, 2:
- Pulmonary artery catheters
- Bladder catheters
- Esophageal thermistors
When central monitoring unavailable, use oral or rectal temperatures—avoid unreliable methods like axillary or tympanic measurements 1, 3, 2
Continuous monitoring is preferable to intermittent measurements for closer temperature control 2
Critical Caveats
What NOT to Do
- Do not routinely use antipyretics solely for temperature reduction in non-neurologically ill critically ill patients, as this has not improved 28-day mortality, hospital mortality, or shock reversal 1, 3
- Do not treat the thermometer number rather than the patient's symptoms in general ICU populations 3
When to Treat Aggressively
The key distinction is neurological injury changes the risk-benefit calculation 1, 2:
- Patients with pontine hemorrhage, subarachnoid hemorrhage, stroke, or other CNS disorders require aggressive fever treatment to normal levels 2
- These patients should be managed in ICU settings given acuity, frequent ICP elevations, and multiple medical complications 2
Predictors of Central vs Infectious Fever
Central fever is more likely when 6:
- Onset within 72 hours of ICU admission (OR 2.20)
- Diagnosis of subarachnoid hemorrhage, intraventricular hemorrhage, or tumor (OR 6.33)
- Absence of infiltrate on chest x-ray (OR 3.02)
- Recent blood transfusion (OR 3.06)
- Persistent fever lasting >6 hours for ≥2 consecutive days
The combination of negative cultures, no chest x-ray infiltrate, CNS hemorrhage/tumor diagnosis, and fever onset within 72 hours predicts central fever with 90% probability 6