What is the recommended fluid resuscitation strategy?

Fluid Resuscitation Strategy

Initiate resuscitation with crystalloid solutions, specifically administering at least 30 mL/kg within the first 3 hours, using balanced crystalloids (lactated Ringer's or Plasma-Lyte) as the preferred choice over normal saline. 1, 2

Initial Fluid Selection and Administration

Crystalloids are the mandatory first-line resuscitation fluid for all patients requiring volume resuscitation, with strong evidence supporting this approach over colloids. 3

Crystalloid Type Selection:

• Balanced crystalloids (lactated Ringer's or Plasma-Lyte) should be preferentially selected over normal saline to minimize the risk of hyperchloremic metabolic acidosis, which can worsen outcomes particularly in patients with renal dysfunction. 1, 2
• Normal saline remains acceptable when balanced solutions are unavailable, though it carries increased risk of acid-base disturbances. 3
• The choice between balanced and unbalanced crystalloids represents a weak recommendation due to low-quality evidence, but the physiologic rationale strongly favors balanced solutions. 3

Volume and Timing:

• Administer a minimum of 30 mL/kg of crystalloid within the first 3 hours of recognizing sepsis-induced hypoperfusion or shock. 1, 2
• More rapid administration and larger volumes may be required based on individual hemodynamic response. 3, 2
• Use a fluid challenge technique with boluses of 250-1000 mL administered rapidly and reassessed after each administration. 2

Fluid Challenge Technique

Continue fluid administration only as long as hemodynamic parameters demonstrate ongoing improvement. 3, 1

Assessment Parameters:

• Dynamic measures are superior to static measures for predicting fluid responsiveness, including pulse pressure variation and stroke volume variation. 1, 2
• Static variables (arterial pressure, heart rate, mental status, urine output, skin perfusion) should supplement but not replace dynamic assessment. 3, 2
• Central venous pressure (CVP) should NOT be used alone to guide fluid therapy due to poor predictive ability for fluid responsiveness. 1, 2

Stopping Criteria:

• Discontinue fluid administration when hemodynamic parameters stabilize, no further improvement in tissue perfusion occurs, or signs of fluid overload develop (pulmonary edema, increasing oxygen requirements, jugular venous distension). 1, 4

Special Populations and Considerations

Patients with Chronic Kidney Disease:

• Apply the same initial 30 mL/kg crystalloid bolus despite renal dysfunction, as delayed resuscitation increases mortality. 4
• After initial resuscitation, use smaller boluses (250-500 mL) with more frequent reassessment due to impaired fluid excretion capacity. 4
• Monitor more aggressively for fluid overload given limited renal excretory function. 4
• Consider earlier vasopressor initiation (norepinephrine) to maintain perfusion while limiting excessive fluid volumes. 4

Pediatric Patients:

• Administer 20 mL/kg boluses for children with septic shock, with subsequent reassessment after each bolus. 3
• Total fluid administration up to 40-60 mL/kg in the first hour may be appropriate in systems with intensive care availability, titrated to response. 3
• In resource-limited settings without intensive care, limit to 40 mL/kg total in the first hour if hypotensive. 3
• Do NOT administer routine bolus fluids to febrile children who are not in shock, as this may worsen outcomes. 3

Upper Gastrointestinal Bleeding:

• Crystalloids remain the fluid of choice over colloids, as colloids provide no survival benefit and are more expensive. 3
• Balanced crystalloids (Ringer's lactate) may reduce acute kidney injury compared to normal saline. 3
• Evidence is insufficient to recommend restrictive versus liberal fluid strategies, but the priority is stopping bleeding while minimizing hemodynamic compromise. 3

Albumin Considerations

Albumin may be added to crystalloids when patients require substantial amounts of crystalloid resuscitation, though this represents a weak recommendation with low-quality evidence. 3, 2

• Albumin does not improve mortality compared to crystalloids alone in most patients. 3
• Consider albumin supplementation when crystalloid requirements exceed 60-80 mL/kg to potentially reduce total volume needed. 2, 4

Fluids to Avoid

Hydroxyethyl starches are absolutely contraindicated for resuscitation, with strong evidence demonstrating increased mortality and acute kidney injury. 3, 1, 4

• Gelatins should be avoided in favor of crystalloids based on weak evidence. 3
• Dextrans and other synthetic colloids lack evidence of benefit and carry risk of adverse effects. 3

Critical Pitfalls to Avoid

• Never delay initial resuscitation due to concerns about fluid overload—delayed resuscitation definitively increases mortality and trumps theoretical fluid overload concerns. 1, 4
• Do not rely on CVP alone to guide fluid therapy, as it poorly predicts fluid responsiveness and can lead to both under- and over-resuscitation. 1, 2
• Continuous reassessment is mandatory after each fluid bolus to detect both inadequate resuscitation and fluid overload at early stages. 3, 2
• Do not use dopamine for renal protection—it is ineffective and potentially harmful. 1

Vasopressor Integration

If hypotension persists despite adequate fluid resuscitation, initiate norepinephrine as the first-choice vasopressor targeting mean arterial pressure ≥65 mmHg. 1, 2

• Vasopressors should complement, not replace, adequate fluid resuscitation in the initial phase. 3
• Earlier vasopressor initiation may be appropriate in patients with chronic kidney disease or other conditions where excessive fluid administration poses significant risk. 4