What is the recommended treatment for a patient with central fever, possibly with a history of brain injury or neurological conditions?

Treatment of Central Fever

For patients with central fever following brain injury, initiate controlled normothermia immediately using automated feedback-controlled temperature management devices targeting 36.0-37.5°C, as antipyretic medications alone are insufficient for effective temperature control in this population. 1, 2

Initial Assessment and Diagnosis

While investigating the fever source, treatment should begin immediately without delay, as fever duration correlates with worse neurological outcomes regardless of etiology 3. Key diagnostic steps include:

• Obtain chest radiograph and at least two sets of blood cultures (60 mL total) to rule out infectious causes 2, 3
• Consider lumbar puncture if mental status changes are unexplained and no contraindications exist 4
• Perform CT imaging if recent surgery to exclude surgical site infections 2
• Recognize that up to 50% of fever in neurocritical care patients is non-infectious in origin 4

The critical distinction is that while you investigate for infection, temperature control must proceed simultaneously—do not wait for culture results to begin treatment. 3

Temperature Management Strategy

Primary Intervention: Automated Temperature Control

Automated feedback-controlled temperature management devices are the recommended first-line approach for severe brain injury patients, as they provide precise control that antipyretics cannot achieve 1, 2. These devices should:

• Target core temperature of 36.0-37.5°C 1, 2
• Maintain temperature variation ≤±0.5°C per hour and ≤1°C per 24-hour period 1, 2
• Continue for as long as the brain remains at risk of secondary injury 1

Monitoring Requirements

Use central temperature monitoring (bladder catheter, esophageal, or pulmonary artery catheter) rather than peripheral measurements, as brain temperature can be up to 2°C higher than systemic temperature 1, 3. Continuous monitoring is preferable to intermittent measurements 1.

Role of Pharmacological Agents

Limited Efficacy of Antipyretics

Antipyretic medications (acetaminophen, NSAIDs) have limited efficacy in controlling fever in severe brain injury and should only serve as adjuncts during the induction phase, not as primary therapy 1, 2. This represents a critical pitfall—relying solely on antipyretics is insufficient 1.

Despite their limited effectiveness, guidelines still recommend their use:

• Acetaminophen or NSAIDs may be reasonable as adjunctive therapy 4, 3
• Daily dosages up to 6000 mg of acetaminophen showed modest temperature-lowering effects in stroke patients 4

Alternative Pharmacological Approach

For central fever specifically related to autonomic dysfunction (manifested by tachycardia, profuse sweating, and decorticate posturing), propranolol 20-30 mg every 6 hours has demonstrated effectiveness in reducing temperatures by at least 1.5°C within 48 hours 5. This should be continued until all signs of autonomic dysfunction resolve 5.

Pathophysiological Rationale

Fever control is critical because elevated temperature:

• Increases brain metabolic rate, cerebral blood flow, and intracranial pressure 1, 6
• Enhances release of neurotransmitters and increases free radical production 4
• Aggravates excitotoxicity, inflammation, and apoptosis 6
• Is independently associated with poor neurological outcomes and increased mortality 4, 6

Duration and Monitoring

Continue controlled normothermia throughout the acute phase while the brain remains at risk of secondary injury 1. This is particularly important in patients with:

• Seizures or high seizure risk 1
• Impending herniation or obliterated basal cisterns 1
• Significant mass effect requiring tier 1-2 ICP management 2

Common Pitfalls to Avoid

• Do not rely solely on antipyretics for temperature control in severe brain injury—they are inadequate as monotherapy 1, 2
• Do not delay treatment while searching for fever source—begin temperature control immediately 3
• Do not discontinue temperature control prematurely while the brain remains at risk of secondary injury 1
• Do not use peripheral temperature measurements (axillary, tympanic) when central monitoring is available 1, 3
• Do not attribute fever to central causes without first investigating infectious sources, as this may lead to missed treatable infections 1