Fresh frozen plasma can be administered at 10 to 20 ml/kg/day to replenish clotting factors and provide antiproteinase activity
in states of inflammation, such as pancreatitis, and provide small quantities of albumin.6 Infuse 20 ml/kg plasma for every 0.5 g/dl increase in plasma albumin needed, provided no ongoing losses are present. The
goal of plasma administration is to raise a patient's serum albumin concentration to 2 g/dl; once this goal is achieved, provide
the remainder of colloidal support with synthetic colloids.
Examples of artificial colloids include hetastarch, dextran 40, dextran 70, and polymerized bovine hemoglobin glutamer-200
(Oxyglobin—Biopure). Hetastarch and dextrans are commonly used in veterinary practice. Concentrated human serum albumin (HSA)
(25% albumin; ASD Healthcare) should be considered in severe cases of hypoalbuminemia (albumin < 2 g/dl).
Hetastarch. Hetastarch is a polymer of amylopectin suspended in a lactated Ringer's solution. The average molecular weight of hetastarch
is 69,000 daltons. The hetastarch particles are broken down by serum amylase and last in circulation for about 36 hours. Because
hetastarch can bind with von Willebrand factor, a patient's activated partial thromboplastin time (APTT) and activated clotting
time (ACT) may become mildly prolonged, but this will not contribute to or cause bleeding.
Administer hetastarch in incremental boluses of 5 to 10 ml/kg in dogs and 5 ml/kg in cats. Because rapid hetastarch administration
can cause histamine release and vomiting in cats, administer the bolus slowly over 15 to 20 minutes. Many authors recommend
that the total daily dose of hetastarch should not exceed 20 to 30 ml/kg/day.6 After administering the boluses, administer hetastarch as a constant-rate infusion (20 to 30 ml/kg/day intravenously) until
the patient is able to maintain its serum albumin concentration and colloidal support on its own. During hypovolemic shock,
5 to 10 ml/kg can be given as an intravenous bolus.
Dextran. Dextran solutions contain polymers of glucose with average molecular weights of 40 and 70 daltons. Most practitioners favor
dextran 70 over dextran 40 because dextran 70's larger particles contribute to the water-holding capacity of blood. The smaller
particles of dextran 40 last about four hours in circulation before being cleared by the kidneys. The larger particles of
dextran 70 last about nine hours in circulation.
Both dextran 40 and dextran 70 coat platelets and red blood cells and can impair coagulation and interfere with cross-match
procedures. For this reason, dextran 70 may be preferred over hetastarch in conditions of hypercoagulability and thrombosis.
Anaphylaxis and renal failure have been reported in people that received dextran 40.6 The dose is 10 to 20 ml/kg/day given intravenously when administered along with a crystalloid. During hypovolemic shock,
5 ml/kg can be administered as an intravenous bolus to treat hypotension.
Polymerized bovine hemoglobin glutamer-200. This solution contains bovine stroma-free hemoglobin that acts both as a potent colloid and as an oxygen carrier in the face
of thrombosis or anemia. Recommended doses are 20 to 30 ml/kg/day. Polymerized bovine hemoglobin glutamer-200 can be administered
as an intravenous bolus of 3 to 7 ml/kg. Use caution when infusing this solution in normovolemic patients and in those with
congestive heart failure because of the risk of causing iatrogenic volume overload.
HSA. Albumin contributes 80% of the oncotic pressure of blood and acts as a carrier for various essential compounds in the body,
including hormones, zinc, copper, and drugs. Albumin is also a mediator of coagulation and a free-radical scavenger at sites
of inflammation. Hypoalbuminemia (albumin < 2 g/dl) has been associated with delayed wound healing and an overall increase
in patient mortality.10 Patients with conditions associated with increased capillary pore size, such as sepsis, vasculitis, and systemic inflammatory
response syndrome, can benefit from maintaining the serum albumin concentration at or ideally above 2 g/dl.