IV Fluid Bolus for Dehydration
For a dehydrated adult patient, administer 500-1000 mL of isotonic crystalloid (preferably balanced solution like lactated Ringer's or Plasmalyte) over 15-30 minutes, then reassess and repeat as needed based on clinical response.
Initial Bolus Recommendations by Clinical Context
Sepsis/Septic Shock
- Give at least 30 mL/kg of IV crystalloid within the first 3 hours 1
- For a 70 kg adult, this equals approximately 2100 mL
- WHO guidelines recommend 1000 mL crystalloid immediately, continued at 20 mL/kg/hour (maximum 60 mL/kg in first 2 hours) 2
- Alternative approach: 500-1000 mL boluses over 30 minutes, repeated based on response 2
Severe Dehydration (≥10% fluid deficit)
- Administer 20 mL/kg boluses of Ringer's lactate or normal saline until pulse, perfusion, and mental status normalize 3
- For a 70 kg adult, this equals 1400 mL per bolus
- Repeat boluses until hemodynamic stability achieved 4
Moderate Dehydration (6-9% fluid deficit)
- Give 100 mL/kg over 2-4 hours 3
- For a 70 kg adult, this equals 7000 mL total over 2-4 hours
Mild Dehydration (3-5% fluid deficit)
- Administer 50 mL/kg over 2-4 hours 3
- For a 70 kg adult, this equals 3500 mL over 2-4 hours
Fluid Type Selection
Prioritize balanced crystalloid solutions over normal saline 5, 6. Balanced solutions (lactated Ringer's, Plasmalyte) reduce:
- Length of hospital stay 5
- Risk of hyperchloremic metabolic acidosis 7, 6
- Risk of acute kidney injury 7, 6
Normal saline is appropriate when:
- Sodium or chloride deficits exist 7
- Severe liver dysfunction is present (avoid lactate-buffered solutions) 5
Reassessment Algorithm
After each bolus, evaluate:
- Heart rate - should decrease toward normal
- Blood pressure - systolic should rise above 90 mmHg, MAP ≥65 mmHg 1
- Capillary refill - should improve to <2 seconds 8
- Mental status - should normalize 3
- Urine output - target ≥0.5 mL/kg/hour 1
- Skin perfusion - warm extremities, reduced mottling 8
Critical Pitfalls to Avoid
Stop or slow fluid administration if signs of overload develop:
- Increased jugular venous pressure
- New or worsening pulmonary crackles/rales
- Peripheral edema
- Rapid weight gain 2, 8
In patients with heart failure, renal failure, or hepatic failure: Restrict to 50-60% of calculated volumes 5
In resource-limited settings with sepsis: More than 4 L crystalloid may be required in the first 24 hours 8, but aggressive boluses in children with compensated shock and severe anemia have shown harm 8
Ongoing Management
- Continue reassessing hemodynamic status frequently 1
- Use dynamic variables (passive leg raise, pulse pressure variation) over static variables (CVP) to predict fluid responsiveness 1
- Replace ongoing losses: 10 mL/kg for each watery stool, 2 mL/kg for each episode of vomiting 3
- Consider vasopressors if hypotension persists after 60 mL/kg within first 2 hours 2