Can a patient with a cerebrovascular accident develop pyrexia?

Can You Have a Fever with a Stroke?

Yes, fever is a common complication of stroke, occurring in approximately 37-50% of hospitalized stroke patients, and it is strongly associated with worse neurological outcomes and increased mortality. 1, 2, 3

Epidemiology and Timing

• Fever develops in 37.6% to 50% of patients hospitalized for acute stroke 2, 3
• Body temperature can rise to 39°C within 12 hours after stroke onset and typically peaks within the first 24 hours 4
• The incidence is particularly high in patients with basal ganglia hemorrhage, lobar hemorrhage, and especially intraventricular hemorrhage 5

Two Distinct Types of Post-Stroke Fever

Infectious Fever (Most Common)

• Accounts for approximately 60% of febrile episodes (22.7% of all stroke patients) 3
• Most commonly caused by:
  • Aspiration pneumonia (the leading cause)
  • Urinary tract infections (especially with catheterization)
  • Infections related to invasive procedures 1, 3
• Typically develops later in the hospital course 3, 6
• Responds to appropriate antibiotic therapy 6

Central (Neurogenic) Fever

• Accounts for approximately 40% of febrile episodes (14.8% of all stroke patients) 3, 6
• Occurs when no infectious source can be identified despite thorough investigation 1, 6
• Most commonly associated with:
  • Brainstem hemorrhage (most common location)
  • Basal ganglia and thalamic hemorrhage
  • Large cortical infarctions
  • Intraventricular hemorrhage 4
• Characterized by earlier onset of fever (within first 24-48 hours) 3, 6
• Does not respond well to antipyretic medications 6
• Associated with higher fever peaks and greater clinical severity 6

Clinical Characteristics That Predict Fever

Patients who develop post-stroke fever tend to have: 3

• Older age (independent predictor)
• More severe strokes (lower Glasgow Coma Scale and Scandinavian Stroke Scale scores)
• Intracerebral hemorrhage rather than ischemic stroke
• Mass effect and transtentorial herniation
• Larger infarct or hemorrhage size
• Use of invasive techniques (urinary catheterization, endotracheal intubation, nasogastric tubes)

Prognostic Impact

Fever after stroke is independently associated with markedly worse outcomes: 1, 5

• Increased morbidity and mortality (meta-analysis evidence) 1
• Larger final infarct size 7
• Worse functional outcomes on Modified Rankin Scale and Barthel Index 3
• The duration of fever is directly proportional to poor prognosis and serves as an independent predictor in patients who survive beyond 72 hours 5

Mechanisms of Injury

Fever worsens stroke outcomes through: 1, 7

• Enhanced metabolic demands
• Increased release of excitatory neurotransmitters
• Exaggerated free radical production
• Blood-brain barrier breakdown
• Increased intracranial pressure 5
• Impaired recovery of energy metabolism

Management Recommendations

When to Treat Fever

All fever (core temperature ≥38°C) in acute stroke patients should be treated aggressively with antipyretic agents while simultaneously investigating the source. 1, 5

First-Line Treatment

• Acetaminophen (paracetamol) is the first-line antipyretic, administered at 1g every 4-6 hours (maximum 4g/24 hours) 5, 8
• Begin treatment immediately when fever is documented, even before infection workup is complete 5
• Target normothermia of 36-37°C 1, 5

Infection Workup

Before labeling fever as "central," perform systematic evaluation: 5

• Bedside swallow screening (aspiration is a major risk factor)
• Chest radiograph
• Urinalysis and urine culture
• Blood cultures if indicated
• Consider other sources based on clinical context

Distinguishing Central from Infectious Fever

Key differentiating feature: timing of onset 3, 6

• Central fever: Onset within first 24-48 hours, higher peaks, poor response to antipyretics
• Infectious fever: Later onset (typically after 48-72 hours), responds to appropriate antibiotics

Advanced Temperature Management

If fever persists despite antipyretics: 1, 5

• Consider automated feedback-controlled temperature management devices for precise control
• Target maximum temperature variation ≤±0.5°C per hour and ≤1°C per 24 hours 5
• Physical cooling measures (sponging, fanning) cause discomfort and are not recommended 9

Critical Warnings

• Deep hypothermia (32-34°C) is NOT recommended due to high complication rates including coagulopathy (each 1°C drop reduces clotting factor activity by ~10%), pulmonary complications, and risk of rebound intracranial hypertension 5
• Routine prophylactic antipyretics in normothermic stroke patients are not evidence-based and provide no outcome benefit 1, 5, 8
• Acetaminophen has only modest efficacy in stroke-associated fever, lowering temperature by approximately 0.26°C within 4 hours 8, 2
• Maximum acetaminophen dose should not exceed 3-4g/day to avoid hepatotoxicity 2