Is there evidence for using crystalloids (intravenous fluids) in hemorrhagic shock?

From the Guidelines

Yes, there is evidence for using crystalloids in hemorrhagic shock as initial resuscitation fluid, with balanced crystalloids like lactated Ringer's or Plasma-Lyte preferred over normal saline (0.9% NaCl) for most patients. The most recent and highest quality study, published in 2022 1, suggests that while there is no significant difference in mortality or acute renal failure between balanced and non-balanced crystalloids, the potentially deleterious effects on renal function and survival of high-volume chloride-rich solutions should orient first-line treatment choices toward balanced solutions.

Key Considerations

• Initial resuscitation typically involves rapid infusion of 1-2 liters of warm crystalloid solution through large-bore IV access, followed by reassessment of vital signs and perfusion status.
• The goal is to maintain a mean arterial pressure of 60-65 mmHg (permissive hypotension) until definitive hemorrhage control is achieved, as higher pressures may worsen bleeding.
• Crystalloids work by expanding intravascular volume, though they distribute to the extravascular space within hours, requiring approximately three times the volume of actual blood loss for adequate resuscitation.
• While crystalloids are readily available and inexpensive, large volumes can cause dilutional coagulopathy, hypothermia, and tissue edema.

Additional Recommendations

• In severe hemorrhagic shock, crystalloids should be used as a bridge to blood product administration (packed red blood cells, plasma, and platelets), ideally in a 1:1:1 ratio, which better addresses the complex pathophysiology of hemorrhagic shock including coagulopathy 1.
• Platelets should be administered to maintain a platelet count above 50×10^9/l in patients with ongoing bleeding and/or traumatic brain injury.
• Mechanical thromboprophylaxis with intermittent pneumatic compression and/or anti-embolic stockings may be applied as soon as possible, and pharmacological thromboprophylaxis should be employed within 24 h after bleeding has been controlled.

From the Research

Evidence for Crystalloid Use in Hemorrhagic Shock

• The use of crystalloids in hemorrhagic shock has been studied in various research papers, with some indicating that crystalloids can be life-saving in severe cases 2.
• However, other studies suggest that the use of crystalloids should be minimized, and instead, plasma should be used as the primary means for volume expansion in traumatic hemorrhagic shock 3.
• A study comparing the effects of normal saline and lactated Ringer's solution on resuscitation markers found that both solutions can lead to marked acidosis, but lactated Ringer's solution elevated lactate levels, while normal saline negatively affected the base deficit 4.
• Another study found that bicarbonated Ringer's solution can be used to supplement missing extracellular fluid and correct metabolic acidosis, and it was associated with lower incidence of complications and shorter intensive care unit length of stay compared to lactated Ringer's solution 5.

Key Findings

• Crystalloids can be used in hemorrhagic shock, but their use should be carefully considered and monitored 2, 4.
• The type of crystalloid used can affect the patient's outcome, with some solutions leading to increased lactate levels or negative effects on base deficit 4, 5.
• Plasma is recommended as the primary means for volume expansion in traumatic hemorrhagic shock 3.
• Bicarbonated Ringer's solution may be a suitable alternative to lactated Ringer's solution for resuscitation in hemorrhagic shock 5.

Resuscitation Strategies

• The primary goal of resuscitation in hemorrhagic shock is to stop the bleeding and restore circulating blood volume 2, 6.
• The use of crystalloids, colloids, and blood products can be life-saving in severe cases of hemorrhagic shock 2.
• A hemoglobin level of 7-8 g/dl appears to be an appropriate threshold for transfusion in critically ill patients with no evidence of tissue hypoxia, but maintaining a higher hemoglobin level of 10 g/dl is a reasonable goal in actively bleeding patients 2.