Formula & Concentration
Albumin (Human) 25%
Since the oncotic pressure of AlbuRx® 25, Albumin (Human) 25% solution is about four times higher than that of normal human serum, it will expand the plasma volume if interstitial water is available for an inflow through the capillary walls. However, many patients suffering from an acute volume deficit also have some degree of interstitial dehydration. In the absence of hyperhydration, the treatment of an acute volume deficit with AlbuRx® 25 should therefore include isotonic electrolyte solutions with an albumin:electrolyte ratio of 1:3 or 1:4. By contrast, chronic volume deficits have usually been at least partially compensated for by the renal retention of sodium and water with some degree of tissue edema, and in these circumstances a trial with AlbuRx® 25 only is indicated. In any case, an anemia of clinically relevant magnitude requires specific treatment, and the metabolic needs of the patient with respect to fluid and electrolytes must be cared for.
The common causes of hypoproteinemia are protein-calorie malnutrition, defective absorption in gastro-intestinal disorders, faulty albumin synthesis in chronic hepatic failure, increased protein catabolism postoperatively or with sepsis, and abnormal renal losses of albumin with chronic kidney disease. In all these settings, the circulating albumin mass is initially maintained by a gradual transfer of extravascular albumin to the circulation, and hypoproteinemia ensues only when this compensatory potential has been exhausted. This implies that manifest hypoproteinemia is usually accompanied by a hidden extravascular albumin deficit of equal magnitude as the measurable intravascular deficit, which must be allowed for if AlbuRx® 25, Albumin (Human) 25% solution is infused because of the capillary permeability of that protein.
The primary sequel of the oncotic deficit resulting from hypoproteinemia is a loss of plasma and a gain of interstitial volume with increased lymphatic flow. As a secondary response, the kidney retains sodium and water which distribute themselves on both sides of the capillary walls and the plasma volume may be returned almost to normal when the interstitial hydrostatic pressure increases sufficiently to compensate for the decrease of the serum oncotic pressure. This chain of events is accelerated by the infusion of crystalloid fluids. The plasma volume is maintained at the price of interstitial edema.2
There is some evidence that a serum oncotic pressure near 20 mmHg – equaling a total serum protein (TSP) concentration of 5.2 g/100 mL – represents a threshold, below which the risk of complications increases.17 The target organs of hypoproteinemia include the skin, the lungs, and the intestine.10 Cutaneous edema lowers the oxygen tension of wounds and may thus impair the healing process.5 An oncotic deficit favors the development of interstitial pulmonary edema4 and the intestinal accumulation of fluids, which may progress to a paralytic ileus.9
Relief of the basic pathology is the definitive mode of therapy for the restoration of the plasma protein content, but this process takes time to become effective, and the rapid correction of a critical oncotic deficit by the administration of AlbuRx® 25, Albumin (Human) 25% solution – possibly in conjunction with a diuretic – may therefore be indicated, particularly in high-risk patients who have undergone abdominal, cardio-vascular, thoracic, or urologic surgery or who have acute bacteremia. In notably catabolic patients, attempts to raise the TSP level above 6 g/100 mL usually prove futile, even with massive doses of Albumin (Human).17 It is emphasized that whereas AlbuRx®25, Albumin (Human) 25% solution may be necessary to prevent or treat the aforementioned acute complications of hypoproteinemia, it is not indicated for treatment of the chronic condition itself.
Shelf Life and Storage
AlbuRx® 25, Albumin (Human) 25% solution should be stored at a temperature not exceeding 30°C (86°F). It should not be used after the expiration date printed on the label.