Frequently-Asked Questions on Pentaspan
[Q1] What is Pentaspan?
[A1] Pentaspan is 10% pentastarch in 0.9% sodium chloride. It is an artificial colloid (hydroxyethyl starch derivative).
[Q2] What is the primary intended use of Pentaspan?
[A2] The primary intended use of Pentaspan is as a substitute for older colloids such as albumin or hetastarch for use in plasma volume expansion. (http://www.micromedex.com/products/drugdex/updates/penta.htm)
[Q3] Name some clinical settings where Pentaspan has been used.
[A3] A number of clinical studies have demonstrated the safety of Pentaspan for plasmapheresis, vascular surgery, cardiopulmonary bypass, resuscitation after major burns or during sepsis syndrome, and hemodilution therapy after stroke.
(http://www.micromedex.com/products/drugdex/updates/penta.htm)
[Q4] How is Pentastarch administered?
[A4] Pentastarch is administered via the intravenous route.
(http://www.micromedex.com/products/drugdex/updates/penta.htm)
[Q5] What is the usual dose of Pentaspan?
[A5] The usual dose administered for the purposes of plasma volume expansion is 500 to 1000 mL, and should not to exceed 2000 mL daily under ordinary circumstances.
(http://www.micromedex.com/products/drugdex/updates/penta.htm)
[Q6] Which is eliminated faster from the body, pentastarch or hetastarch?
[A6] As a result of its lower molecular weight and lesser degree of substitution, pentastarch is eliminated from the circulation at a faster rate than hetastarch. Ordinarily, only 10% of an intravenous dose remains after 24 hours, and levels are undetectable after 4 to 7 days.
(http://www.micromedex.com/products/drugdex/updates/penta.htm)
[Q7] How is pentastarch eliminated from the body?
[A7] Pentastarch is hydrolyzed by plasma amylase, and this is more rapid and complete compared to hetastarch. Up to 70% of a dose is excreted in the urine within 24 hours. The elimination half-life of pentastarch is approximately 2.5 hours, which is substantially shorter than that of hetastarch.
(http://www.micromedex.com/products/drugdex/updates/penta.htm)
[Q8] List some clinical adverse effects that may occur when Pentaspan is used.
[A8] Potential adverse effects include hemostatic abnormalities (eg, prolonged prothrombin time and activated partial thromboplastin time (aPTT), and reductions in platelet counts, hemoglobin, and factor VIII levels). This is at least partly as a result of hemodilution. The effects on hemostasis are less than those observed with hetastarch. Other potential adverse effects include hypersensitivity reactions (rare), edema, weight gain, headache, fatigue, and nausea.
(http://www.micromedex.com/products/drugdex/updates/penta.htm)
[Q9] Where does pentastarch end up after it is administered?
[A9] Most of an infused dose of pentastarch is excreted in the urine. Prudence dictates that one avoid pentastarch in patients with renal disease complicated by oliguria or anuria unless it is related to hypovolemia.
(http://www.micromedex.com/products/drugdex/updates/penta.htm)
[Q10] Why is microvascular integrity important in intravenous fluid therapy?
[A10] "Administration of various types of fluid intravenously is frequently required to resuscitate perioperatively or critically ill patients. Crystalloids, plasma, albumin, or synthetic colloids such as gelatin, dextran, or hydroxyethyl starches (HESs) are the current options for this purpose. Intravenous fluid administration is well tolerated if the microvascular integrity is preserved, but the inflammatory response that occurs in sepsis, trauma, shock, and anaphylaxis results in increased vascular permeability. Significant vascular leakage causes interstitial edema, which may adversely affect organ function: cerebral edema causes mental status changes, pulmonary edema impairs gas exchange, myocardial edema decreases compliance, edematous tissues have impaired wound healing, and gut edema decreases nutrient absorption and increases bacterial translocation." (Traylor: Anesth Analg, Volume 83(2). August 1996. 209-212)
[Q11] Are all colloids more or less the same?
[A11] "It is increasingly clear that the effects of different colloids are different. Colloids vary markedly in their size, number average molecular weight (the arithmetic mean of all particle molecular weights), and weight average molecular weight (the sum of the number of molecules at each weight times the particle weight divided by the total weight of all molecules). Monodisperse solutions have one size of particle so that weight average and number average molecular weight are similar. Polydisperse solutions have a diverse range of molecular sizes and shapes, causing disparity between the weight average and the number average molecular weight. There are many colloid suspensions available with varying molecular sizes, half-lives, colloid oncotic pressures, side effects, and costs."
(Traylor: Anesth Analg, Volume 83(2). August 1996. 209-212)
[Q12] Why is Albumin an important colloid?
[A12] "Albumin accounts for 60%-80% of normal plasma oncotic pressure. Albumin is expensive because it is derived from pooled human plasma. Despite its multiple physiologic roles, albumin levels are best used as a prognostic indicator rather than as an absolute value to be maintained with exogenous albumin administration. Recent studies show that albumin administration can maintain oncotic pressure but does not decrease morbidity or mortality in critically ill patients. One explanation for the lack of benefit is continued extravascular leak of albumin, a monodisperse compound with a low molecular weight." (Traylor: Anesth Analg, Volume 83(2). August 1996. 209-212)
[Q13] What are Dextrans?
[A13] "Dextrans are composed of linear polysaccharide molecules whose molecular weight ranges from 10 to 90 kilodaltons (kd). Dextrans can improve microvascular circulation by decreasing blood viscosity and by coating vascular endothelial cells to minimize platelet and red blood cell aggregation. However, dextrans may produce bleeding by the same mechanism and are associated with a 1%-5% risk of anaphylaxis."
(Traylor: Anesth Analg, Volume 83(2). August 1996. 209-212)
[Q14] What are Gelatins?
[A14] "Gelatins are polypeptides with a molecular weight of 35 kd. They have limited utility as plasma expanders due to rapid migration from the intravascular space."
(Traylor: Anesth Analg, Volume 83(2). August 1996. 209-212)
[Q15] What are hydroxyethylstarch (HES) compounds?
[A15] "HES compounds are synthetic polymers derived from amylopectin, a branched polysaccharide polymer. The attachment of hydroxyethyl ether groups to the glucose units slows degradation by serum amylase.
(Traylor: Anesth Analg, Volume 83(2). August 1996. 209-212)
[Q16] What influences the pharmacokinetic properties of hydroxyethylstarch (HES) compounds?
[A16] "The pharmacokinetic properties of HES are directly related to the size and the molar substitution ratio (the number of hydroxyethyl groups per molecule of glucose). A higher degree of substitution results in slower breakdown and elimination of the molecule. Particles less than 50 kd are filtered by the kidneys within 48 hours, while larger particles are hydrolyzed by amylase and then excreted in urine and bile or phagocytized by the reticuloendothelial system." (Traylor: Anesth Analg, Volume 83(2). August 1996. 209-212)
[Q17] Is there a concern that hydroxyethylstarch (HES) compounds might be associated with a bleeding diathesis?
[A17] "For many years, there was concern that hetastarch might be associated with a bleeding diathesis. Observed coagulation abnormalities included hemodilution reduction of clotting factors and decreased Factor VIII and von Willebrand factor (vWF) levels. However, studies of cardiovascular patients compared the use of HES with the use of albumin as a pump priming solution and found no differences in bleeding, chest tube drainage, or transfusion requirements. Claes et al. studied the effects of albumin versus HES in neurosurgical and gynecological patients. Coagulation variables remained within the physiological range, but factor VIII and vWF levels decreased from baseline values. This decrease may be clinically relevant in patients with initially low levels as in disseminated intravascular coagulation, hemophilia, and von Willebrand's disease. Doses of HES larger than recommended have been used, resulting in moderate abnormalities in coagulation variables but no clinical bleeding or organ toxicity."
(Traylor: Anesth Analg, Volume 83(2). August 1996. 209-212)
[Q18] When are colloidal solutions (colloids) used in clinical medicine?
[A18] "Colloidal solutions are used not only in the acute treatment of hemorrhagic shock, but also in the treatment of critically ill patients after trauma, after major surgery or during sepsis. Natural colloids, such as plasma protein solutions and human serum albumin, as well as artificial colloids, such as dextran and gelatin, are available in many different pharmacologic modifications."
(Crit Care Med 1995; 23:806-814)
[Q19] List some drawbacks the use of colloids in clinical medicine.
[A19] "Each of these substances carries certain risks of complications: Natural colloids may transmit infectious diseases, such as hepatitis C or the acquired immunodeficiency syndrome, and are also capable of inducing anaphylactoid reactions. The main drawbacks associated with the administration of synthetic colloidal solutions, particularly of dextran, are hypersensitivity reactions and anticoagulant effects."
(Crit Care Med 1995; 23:806-814)
