What is the recommended fluid therapy for adults with fever?

Fluid Therapy in Febrile Adults

Primary Recommendation

For febrile adults with sepsis or septic shock, administer at least 30 mL/kg of balanced crystalloid solution (Ringer's lactate or Plasma-Lyte) within the first 3 hours using repeated fluid boluses of 250-1000 mL with reassessment after each bolus. 1, 2, 3

Clinical Context: When to Give Fluids

Fluid resuscitation is indicated when fever is accompanied by:

• Hypotension (systolic BP <90 mmHg or MAP <65 mmHg) 4
• Clinical markers of hypoperfusion (altered mental status, oliguria, poor peripheral perfusion, prolonged capillary refill) 4
• Lactate ≥2 mmol/L despite adequate oxygenation 4

Critical caveat: For febrile patients WITHOUT signs of shock or hypoperfusion, routine bolus intravenous fluids are NOT recommended and may cause harm. 4

Fluid Type Selection

First-Line Choice: Balanced Crystalloids

Use Ringer's lactate or Plasma-Lyte as your initial resuscitation fluid. 1, 2, 3

The evidence strongly favors balanced crystalloids over 0.9% saline:

• Mortality benefit: Lactated Ringer's solution reduced 30-day mortality (12.2% vs 15.9%, adjusted HR 0.71,95% CI 0.51-0.99) compared to saline in sepsis-induced hypotension 3
• Reduced kidney injury: Lower incidence of major adverse kidney events (35.4% vs 40.1%) and more vasopressor-free days 5
• Avoids complications: Prevents hyperchloremic metabolic acidosis associated with normal saline 1, 6, 5

Avoid These Fluids

• Do NOT use hydroxyethyl starches - increased mortality and acute kidney injury 2
• Avoid hypotonic solutions (D5W) for initial resuscitation - minimal intravascular effect and cerebral edema risk 7
• 0.9% saline is acceptable but inferior to balanced crystalloids 1, 3, 5

Administration Protocol

Initial Resuscitation (First 3 Hours)

1. Give 30 mL/kg of balanced crystalloid (approximately 2-3 liters for a 70 kg adult) 1, 2, 4
2. Use rapid bolus technique: 250-1000 mL administered over <15 minutes 1, 2
3. Reassess after EACH bolus - do not give the entire volume without checking response 1, 2

Reassessment Parameters After Each Bolus

Monitor these specific markers:

• Blood pressure (target MAP ≥65 mmHg) 4, 2
• Heart rate (should decrease with adequate resuscitation) 2
• Mental status (improvement in alertness) 4, 2
• Urine output (target >0.5 mL/kg/hr) 1, 2
• Peripheral perfusion (capillary refill, skin temperature) 4, 2
• Lactate clearance (aim for ≥20% reduction if elevated) 2

When to STOP Fluid Administration

Discontinue further boluses when ANY of these occur:

• No improvement in perfusion markers after a bolus 2
• Signs of fluid overload develop: pulmonary crackles, increased jugular venous pressure, worsening oxygenation 2
• Hemodynamic parameters stabilize (MAP ≥65 mmHg, adequate perfusion) 1, 2

Critical pitfall: Continuing fluids beyond these endpoints increases mortality and complications. 2

Special Populations

Patients with Pre-existing Heart Failure

• Use smaller boluses: 250-500 mL over 15-30 minutes 2
• Reassess more frequently after each smaller bolus 2
• Consider dynamic measures of fluid responsiveness (passive leg raise, pulse pressure variation) 2

Severe Burns with Fever

• Give 20 mL/kg crystalloid in first hour for adults with ≥20% total body surface area burned 4, 1
• Use balanced crystalloids (Ringer's lactate preferred) 4

Vasopressor Initiation

Start norepinephrine if hypotension persists despite adequate fluid resuscitation (after 30 mL/kg or when fluid overload signs appear). 4, 2

• Target MAP ≥65 mmHg (consider higher targets in chronic hypertension) 4, 2
• Can be administered via peripheral IV if central access unavailable, but monitor closely for extravasation 4

What NOT to Do

Common errors that worsen outcomes:

• Delaying initial resuscitation - mortality increases with delay 2
• Using central venous pressure (CVP) alone to guide therapy - static measures are unreliable 2
• Giving entire 30 mL/kg without reassessment - leads to fluid overload 1, 2
• Routine fluid boluses for fever without shock - harmful in some populations 4
• Using antipyretics as primary fever management instead of treating underlying cause 4

Monitoring Beyond Initial Resuscitation

After the first 3 hours, use dynamic measures of fluid responsiveness rather than static measures:

• Pulse pressure variation (if mechanically ventilated) 2
• Stroke volume variation 1
• Passive leg raise test 2

Avoid relying on CVP alone - it poorly predicts fluid responsiveness. 2