Understanding Burn Care: Why is albumin given to burn patients?

Burn injuries affecting more than 20% of the total body surface area (TBSA) trigger a massive inflammatory response, leading to significant fluid shifts and plasma loss. In these severe cases, understanding why is albumin given to burn patients is crucial for managing burn shock, a life-threatening condition caused by severe hypovolemia.

Quick Summary

This article explores the critical role of human albumin solution in treating severely burned patients. It explains how albumin's colloid osmotic pressure helps restore intravascular volume and prevents fluid overload by reducing excessive crystalloid requirements during resuscitation.

Key Points

• Albumin Counters Burn Shock: Severe burns cause massive fluid and albumin loss from the blood vessels, leading to burn shock; albumin infusions help replenish this lost volume. {Link: Adoption of rescue colloid during burn resuscitation decreases fluid creep in patients with major burns https://www.sciencedirect.com/science/article/abs/pii/S0305417921000413}

• Restores Oncotic Pressure: Albumin is the primary driver of colloid osmotic pressure, which pulls fluid back into the bloodstream from the tissues, correcting hypovolemia. {Link: Adoption of rescue colloid during burn resuscitation decreases fluid creep in patients with major burns https://www.sciencedirect.com/science/article/abs/pii/S0305417921000413}

• Reduces Fluid Creep: By effectively expanding blood volume, albumin can reduce the need for excessive crystalloid fluids, a phenomenon known as fluid creep, and its associated complications. {Link: Adoption of rescue colloid during burn resuscitation decreases fluid creep in patients with major burns https://www.sciencedirect.com/science/article/abs/pii/S0305417921000413}

• Timing is Key: Due to initial high capillary leak, albumin is often delayed until 8-12 hours post-burn to maximize its intravascular retention, though it can be used earlier as a 'rescue' therapy. {Link: Adoption of rescue colloid during burn resuscitation decreases fluid creep in patients with major burns https://www.sciencedirect.com/science/article/abs/pii/S0305417921000413}

• Improves Resuscitation Outcomes: Using albumin as an adjunct in resuscitation can lead to reduced fluid requirements, lower rates of certain complications, and shorter hospital stays in some patient populations. {Link: Adoption of rescue colloid during burn resuscitation decreases fluid creep in patients with major burns https://www.sciencedirect.com/science/article/abs/pii/S0305417921000413}

• Part of a Broader Strategy: The use of albumin must be part of a carefully managed and monitored fluid resuscitation protocol, often alongside crystalloids and other supportive therapies. {Link: Adoption of rescue colloid during burn resuscitation decreases fluid creep in patients with major burns https://www.sciencedirect.com/science/article/abs/pii/S0305417921000413}

The Pathophysiology of Burn Shock and Albumin Loss

Severe thermal injuries induce a systemic inflammatory response, increasing capillary permeability. This allows significant amounts of plasma, including albumin, to leak out of the bloodstream into the surrounding tissues. This leakage causes a decrease in blood volume, leading to hypovolemic shock, and a reduction in serum albumin levels (hypoalbuminemia). The loss of albumin reduces the blood's colloid osmotic pressure, further exacerbating fluid movement out of the capillaries and causing severe edema.

The Mechanism: Why is Albumin Given to Burn Patients?

Administering human albumin solution helps counteract the effects of plasma loss by increasing the colloid osmotic pressure within the blood vessels. As a large molecule, albumin primarily stays in the vascular space, drawing fluid from the interstitial space back into the circulation. This helps to:

• Expand Plasma Volume: Restores circulating blood volume and supports cardiac output.
• Restore Oncotic Pressure: Balances hydrostatic and oncotic pressures, helping to reduce edema.

Reducing Fluid Creep

Standard burn resuscitation often involves large volumes of crystalloid fluids. Excessive use of crystalloids can lead to "fluid creep," where more fluid is given than predicted, potentially causing complications like abdominal compartment syndrome and respiratory distress due to edema. Adding albumin can help reduce the total crystalloid volume needed, thus mitigating these risks.

Albumin vs. Crystalloids in Burn Resuscitation

Both crystalloids and colloids like albumin are used in burn resuscitation, often in combination. {Link: Adoption of rescue colloid during burn resuscitation decreases fluid creep in patients with major burns https://www.sciencedirect.com/science/article/abs/pii/S0305417921000413}.

The Timing of Albumin Administration

The timing of albumin administration is debated due to the initial high capillary permeability after a burn. Giving albumin too early might lead to it leaking into tissues and worsening edema. Therefore, some guidelines recommend delaying administration until 8 to 12 hours post-injury when capillary leak decreases. {Link: Adoption of rescue colloid during burn resuscitation decreases fluid creep in patients with major burns https://www.sciencedirect.com/science/article/abs/pii/S0305417921000413}.

Potential Benefits and Considerations

Despite historical debates and cost considerations, albumin offers potential benefits in burn care. {Link: Adoption of rescue colloid during burn resuscitation decreases fluid creep in patients with major burns https://www.sciencedirect.com/science/article/abs/pii/S0305417921000413}.

Conclusion

Administering human albumin is a key part of fluid resuscitation for severely burned patients, especially those with large burn areas or inadequate response to crystalloids alone. {Link: Adoption of rescue colloid during burn resuscitation decreases fluid creep in patients with major burns https://www.sciencedirect.com/science/article/abs/pii/S0305417921000413}.

Frequently Asked Questions

What is the primary purpose of giving albumin to burn patients?

The primary purpose is to help restore the intravascular volume and treat burn shock. Severe burns cause plasma and albumin to leak from blood vessels, leading to dangerously low blood volume. Albumin infusions use colloid osmotic pressure to pull fluid back into the blood from the tissues, stabilizing the patient's circulatory system.

Why is albumin not given immediately after a burn?

In the immediate hours after a burn, the capillaries are at their most permeable, meaning they are very leaky. If albumin is given too early, it can leak into the interstitial space, potentially worsening tissue edema rather than staying in the bloodstream. For this reason, many protocols delay administration until the capillary integrity improves, typically after 8 to 12 hours.

What is 'fluid creep' and how does albumin help prevent it?

'Fluid creep' is the phenomenon of administering excessive amounts of crystalloid fluids during burn resuscitation, which can cause severe edema and complications. Albumin helps prevent this by increasing the blood's osmotic pressure, allowing a smaller total volume of fluid to be used while achieving adequate resuscitation.

Are there specific patient groups that benefit most from albumin?

Yes. Patients with extensive burn injuries (e.g., >20% TBSA) are the primary candidates. It is also recommended for patients who fail to respond adequately to initial crystalloid resuscitation, those with persistent hypovolemia, or those requiring significantly higher-than-predicted fluid volumes.

Is albumin safe for all burn patients?

Albumin is generally considered safe when used appropriately, but like any blood product, it carries some risk. There has been historical debate and conflicting evidence, particularly regarding its effect on mortality, although recent meta-analyses suggest a neutral effect on mortality during acute resuscitation. The decision to administer albumin is based on a careful assessment of the individual patient's condition.

How does albumin compare to crystalloid fluids for burn resuscitation?

Crystalloids, such as Lactated Ringer's, are the initial fluid of choice, but their volume expansion effect is temporary. Albumin, a colloid, provides a more sustained volume expansion due to its larger molecules staying in the intravascular space. While crystalloids are less expensive, albumin is more effective at correcting the oncotic pressure deficit caused by plasma leakage.

What are the guidelines for using albumin in pediatric burn patients?

Pediatric burn patients require special consideration due to their smaller physiological reserves. Some studies have shown that giving albumin earlier (e.g., 8-12 hours post-injury) can reduce crystalloid fluid needs, lessen 'fluid creep', and shorten hospital stays in children with large burns. The American Burn Association provides guidelines specific to this population.