What is the fluid of choice in a patient with shock?

From the Guidelines

The fluid of choice for a patient in shock is crystalloids, specifically 0.9% normal saline or Lactated Ringer's solution, administered as an initial bolus of 30 mL/kg body weight. This recommendation is based on the Surviving Sepsis Campaign guidelines, which suggest that crystalloids should be used as the initial fluid of choice in the resuscitation of severe sepsis and septic shock 1. The guidelines also recommend against the use of hydroxyethyl starches for fluid resuscitation of severe sepsis and septic shock 1.

Some key points to consider when administering fluids to a patient in shock include:

• The initial fluid challenge should aim to achieve a minimum of 30 mL/kg of crystalloids, with more rapid administration and greater amounts of fluid potentially needed in some patients 1
• Fluid administration should be continued as long as there is hemodynamic improvement, based on dynamic or static variables such as arterial pressure, heart rate, and pulse pressure variation 1
• Balanced crystalloids like Lactated Ringer's may be preferable to normal saline in patients at risk for hyperchloremic metabolic acidosis or renal injury
• Blood products should be considered early for hemorrhagic shock, with packed red blood cells transfused to maintain hemoglobin above 7-8 g/dL

It's worth noting that the guidelines suggest using either balanced crystalloids or saline for fluid resuscitation of patients with sepsis or septic shock, although the quality of evidence for this recommendation is low 1. Additionally, albumin may be considered in addition to crystalloids for initial resuscitation and subsequent intravascular volume replacement in patients with sepsis and septic shock, although this recommendation is also based on low-quality evidence 1.

Overall, the goal of fluid resuscitation in shock is to restore tissue perfusion and increase cardiac output and oxygen delivery to tissues, which helps reverse the cellular hypoxia and metabolic derangements that characterize shock states. Fluid responsiveness should be monitored closely using clinical parameters and dynamic measures, and adjustments to fluid administration should be made as needed to achieve optimal hemodynamic status.

From the Research

Fluid of Choice in Shock Patients

The choice of fluid in patients with shock is a critical decision that can impact patient outcomes. According to the available evidence, the following points can be considered:

• Crystalloids are recommended as the first-line therapy for fluid resuscitation in shock patients 2, 3.
• Balanced crystalloids may be a safer alternative to normal saline, as they are associated with lower mortality and kidney injury 2, 3, 4.
• Albumin is similar to crystalloids in terms of outcomes in septic patients, but it is costlier 2, 3.
• Hydroxyethyl starches are no longer indicated in critically ill patients, as they increase mortality and kidney injury 2, 3.
• In trauma patients, the use of plasma-based resuscitation with decreased use of crystalloid and colloid has led to decreased inflammatory and edema-mediated complications 5.
• The optimal choice of fluid remains to be determined, but existing evidence suggests avoiding crystalloids in favor of hypertonic solutions in patients with traumatic brain injury 5.
• Resuscitation with saline resulted in a significantly higher incidence of pulmonary edema than resuscitation with albumin or hetastarch 6.
• The coadministration of balanced crystalloids is associated with lower in-hospital mortality, whereas the use of colloids is associated with increased length of stay and costs per day 4.

Key Considerations

• The type of fluid used in resuscitation can impact patient outcomes, including mortality, kidney injury, and pulmonary edema.
• Crystalloids, particularly balanced crystalloids, are a reasonable choice for initial fluid resuscitation in shock patients.
• The use of colloids, such as hydroxyethyl starches, is not recommended due to increased mortality and kidney injury.
• Further research is needed to determine the optimal fluid choice in different patient populations, including trauma and septic patients.