Do I continue fluid resuscitation in a patient with fluid overload and persistent hyperlactatemia?

Management of Fluid Resuscitation in Patients with Fluid Overload and Persistent Hyperlactatemia

In patients with fluid overload and persistent hyperlactatemia, fluid resuscitation should be reduced or stopped, and alternative strategies for improving tissue perfusion should be initiated, including vasopressors if hypotension is present.

Assessment of Fluid Status and Perfusion

When faced with a patient who has both fluid overload and persistent hyperlactatemia, a careful evaluation of the underlying cause of hyperlactatemia is essential:

• Signs of fluid overload to monitor:

  • Increased jugular venous pressure (JVP)
  • Pulmonary crackles/rales
  • Peripheral edema
  • Decreasing oxygen saturation
  • Radiological evidence of pulmonary edema or pleural effusions

• Perfusion assessment tools:

  • Capillary refill time (CRT): Normal is <2-3s in adults <65 years, <4.5s in those ≥65 years 1
  • Skin temperature and mottling
  • Urine output (target >0.5 mL/kg/hour) 1
  • Mental status changes
  • Central venous oxygen saturation (ScvO2) if available (target >70%) 2

Decision Algorithm

1. Determine if hyperlactatemia is due to hypoperfusion or other causes:

   • Assess for hypoperfusion context: ScvO2 <70%, P(cv-a)CO2 ≥6 mmHg, or CRT ≥4s 3
   • If these markers are absent, hyperlactatemia may be due to non-hypoperfusion causes (adrenergic-driven production, impaired clearance) 3, 4

2. If signs of fluid overload are present:

   • Reduce or stop fluid administration 2
   • WHO guidelines specifically recommend reducing the rate of fluid infusion if clinical signs of fluid overload are present 2
   • Consider vasopressors if hypotension persists despite fluid overload 2, 5

3. If hypotension persists with fluid overload:

   • Initiate norepinephrine as first-line vasopressor 1, 5
   • Target mean arterial pressure (MAP) of 65 mmHg 2, 1
   • Administer through a central venous line using a syringe or infusion pump 2

Rationale and Evidence

The 2020 guidelines for fluid management in sepsis recommend clinical reassessment to detect fluid overload and/or pulmonary edema, with the WHO guideline specifically recommending a reduction in the rate of fluid infusion if clinical signs of fluid overload are present 2. This is critical because continuing aggressive fluid resuscitation in patients with fluid overload can lead to worsened outcomes.

The Surviving Sepsis Campaign guidelines (2017) emphasize that following initial fluid resuscitation, additional fluids should be guided by frequent reassessment of hemodynamic status, including a thorough clinical examination 2. They recommend dynamic over static variables to predict fluid responsiveness.

Recent evidence suggests that hyperlactatemia in sepsis is often caused more by impaired tissue oxygen use rather than impaired oxygen transport 4. This means that additional fluid administration may not address the underlying cause of elevated lactate in many cases, particularly when fluid overload is already present.

Special Considerations

• Lactate clearance as a target: While targeting lactate clearance has been suggested in guidelines 2, recent evidence questions this approach when signs of fluid overload are present 6. A 2021 study indicated that titrating resuscitation to lactate clearance can lead to unnecessary fluid administration and volume overload 6.

• Mortality risk: Patients with persistent hyperlactatemia (>10 mmol/L) and poor lactate clearance (<32.8% at 12 hours) have extremely high mortality rates (>96%) 7. This underscores the importance of appropriate management strategies beyond simply continuing fluid administration.

• Timing of fluid overload: Fluid overload developing later in ICU stay (>24h) is associated with even higher mortality than early fluid overload 7, emphasizing the importance of avoiding excessive fluid administration.

Monitoring Response

• Reassess perfusion markers frequently (every 1-2 hours)
• Monitor for improvement in clinical signs of tissue perfusion
• Track lactate clearance, but interpret in context of other perfusion markers 3, 6
• Evaluate capillary refill time, as normalization after initial resuscitation is associated with better outcomes 8

Remember that continuing fluid administration in patients with clear signs of fluid overload can lead to worsened respiratory function, prolonged mechanical ventilation, and increased mortality. The focus should shift to optimizing cardiac function and tissue perfusion through other means, particularly vasopressors if hypotension is present.