Albumin administration is complicated because of its different concentrations and indications. By the end of this unit, you will be equipped to answer a common clinical dilemma: which concentration to use and how fast to give it.
What is Albumin & How it Works
We have 34-54 grams of albumin per liter of blood in our bodies; it is the most abundant plasma protein (~60%). Albumin is made primarily by the liver.
Its main purpose is to maintain the oncotic pressure of plasma. Oncotic pressure sustains the circulating blood volume; it maintains blood pressure, cardiac output and perfusion throughout the body.
Albumin is too large to pass through the blood vessels; it remains in the intravascular system. This creates a higher solute concentration within the blood vessels which attracts water from extravascular spaces into circulation.
Albumin also plays a significant is role in drug, hormone and enzyme transport around the body.
The commercial preparation of albumin is a simply an aqueous solution of human albumin. We derive albumin from human donors. The donations are then fractionized and pasteurized to produce a sterile product.
Clinical Indications for Albumin
We use albumin when there is some form of blood volume imbalance that we must restore. Whether from net loss or relative loss of circulating blood volume (explained below) albumin can temporarily compensate and maintain circulatory blood flow. This is why we refer to albumin as a “plasma volume expander”.
FDA approved indications include:
- hypovolemia including hypovolemic shock and ovarian hyperstimulation syndrome
- ascites including large volume paracentesis, spontaneous bacterial peritonitis, pancreatitis
- severe burns
Albumin Formulations
25% Albumin:
This formulation contains 25g of albumin per 100 ml of solution.
25% albumin has approximately five times the oncotic pressure of plasma. That means it will increase the gradient for movement of interstitial fluid into the intravascular 5-fold. When we administer 100ml of 25% albumin we effectively administer 500ml of volume expansion.
25% albumin is therefore useful when there is a relative hypovolemia; the volume is present in other extracellular or interstitial compartments.
The efficacy of 25% albumin is fully dependent on the availability of interstitial fluid to flow into the blood vessels.
If nothing is available to pull from (like cases of severe dehydration), 25% albumin will be ineffective.
This higher concentration of albumin is therefore useful in conditions like fluid overload in decompensated heart failure, ascites, severe burns, extensive cellulitis, pancreatitis and septic shock/inflammatory vasodilation.
5% Albumin:
This formulation contains 5g of albumin per 100ml of solution.
5% albumin is oncotically equivalent to that of plasma. This means that it will not increase the gradient for transport of fluid from the extravascular to the intravascular space. It simply stays within the blood vessels. When we administer 100ml of 5% albumin we effectively administer 100ml of volume expansion.
5% albumin is therefore useful when there is a net hypovolemia; there is an overall loss of volume in the body as a whole.
This is any occurrence of hypovolemia not related fluid shift.
Some examples are dehydration from excessive diuresis, severe diarrhea and vomiting, blood loss from major surgery or trauma.
Which to Use: 25% or 5%
Whenever you need to make the decision about which concentration of albumin is needed ask yourself:
Does my patient have a net hypovolemia or relative hypovolemia?
For net hypovolemia: use 5% albumin
For relative hypovolemia: use 25% albumin
How Fast to Administer Albumin
This is a very common question mainly because the rate of administration must consider the patient’s clinical status.
You can run albumin of either concentration relatively quickly (over 30 minutes) if your patient is clinically unstable due to hypovolemia. Our only limit to the rate of administration in this scenario is the capacity of the administration device. In addition, you can repeat the dose if there is an inadequate response in 15 to 30 minutes.
If your patient experiences adverse effects during the infusion, slow the rate. Adverse effects can include rigors and shortness of breath. With that said, albumin infusions are very well tolerated.
The rate of administration is more of a concern with lower acuity patients. We must consider the patient’s volume when selecting a rate of administration. We do not want to tip the scales into hypervolemia or rapidly increases in plasma volume because that can overload the body’s circulatory system. This is known as cardiovascular overload.
Signs of cardiovascular overload include headache and shortness of breath expanding to jugular venous distention and pulmonary edema. Stop the infusion, reassess the patient’s volume status and the continued need for albumin administration.
Bottom line: if your patient is hemodynamically unstable administer albumin quickly. If not administer over 2 hours increasing the rate of administration if desired and if patient demonstrates tolerability.
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The information on this website is intended to be used solely for educational and informational purposes. While the content may be about specific medical and health care issues, it is not a substitute for or replacement of personalized medical advice and is not intended to be used as the sole basis for making individualized medical or health-related decisions.