Dextran 40

WARNINGS Although infrequent, severe and fatal anaphylactoid reactions consisting of marked hypotension or cardiac and respiratory arrest have been reported, most of these reactions have occurred in patients not previously exposed to intravenous dextran and early in the infusion period. It is strongly recommended, therefore, that patients not previously exposed to dextran be observed closely during the first minutes of the infusion period. Anaphylactoid Reactions There have been rare reports of serious and life-threatening dextran-induced anaphylactoid reactions (DIAR) associated with Dextran 40 and Dextran 70 administration. To reduce the likelihood of DIAR, 20 mL dextran 1 should be administered prior to infusion of Dextran 40 or Dextran 70 consistent with the dextran 1 package insert. 1-5 See DOSAGE AND ADMINISTRATION . Investigators have reported a 35-fold decrease (from 1:2000 to 1:70,000) in the incidence of DIAR following prophylactic use of dextran 1. 6 However, serious and life-threatening reactions may still occur following initiation of an infusion of any clinical dextran (see ADVERSE REACTIONS ). Because of the seriousness of anaphylactoid reactions, it is recommended that the infusion of intravenous dextran be stopped at the first sign of an allergic reaction provided that other means of sustaining the circulation are available. Resuscitative measures should be readily available for emergency administration in the event such a reaction occurs. In circulatory collapse due to anaphylaxis, rapid volume substitutions with an agent other than dextran should be instituted. Because LMD (dextran 40) is a hypertonic colloid solution, it attracts water from the extravascular space. This shift of fluid should be considered if the drug is used for poorly hydrated patients where additional fluid therapy will be needed. If LMD is given in excess, vascular overload could occur. The latter possibility can be avoided with careful clinical monitoring preferably by central venous pressure. Renal excretion of LMD causes elevations of the specific gravity of the urine. In the presence of adequate urine flow only minor elevation will occur, whereas in patients with reduced urine output, urine viscosity and specific gravity can be increased markedly. Since urine osmolarity is only slightly increased by the presence of dextran molecules, it is recommended that, when desired, a patient's state of hydration be assessed by determination of urine or serum osmolarity. If signs of dehydration are present, additional fluid should be administered. An osmotic diuretic such as mannitol also can be used to maintain an adequate urine flow. Although numerous studies attest to the "nephrotonic" effect of LMD, renal failure has been reported to occur after the use of LMD. Evidence of tubular vacuolization (osmotic nephrosis) has been found following LMD administration in animals and man. While this appears to be reversible experimentally in animals and to be a consequence of high urine concentration of the drug, its exact clinical significance is presently unknown. Occasional abnormal renal and hepatic function values have been reported following administration of LMD. However, the specific effect of LMD on renal and hepatic function could not be determined because most of the patients also had undergone surgery or cardiac catheterization. A comparative study of dextran 40 and 5% dextrose in water as pump-priming fluids in open-heart surgery has shown similar elevations of serum glutamic oxaloacetic transaminase (SGOT), aspartate aminotransferase and serum glutamic pyruvic transaminase (SGPT), alanine aminotransferase values in both groups. Caution should be employed when LMD is administered to patients with active hemorrhage as the resulting increase in perfusion pressure and improved microcirculatory flow may result in additional blood loss. Administering infusions of LMD that exceed the recommended dose should be avoided, since a dose-related increase in the incidence of wound hematoma, wound seroma, wound bleeding, distant bleeding (hematuria and melena) and pulmonary edema has been observed. Recommended doses should never be exceeded in patients with advanced renal disease, since excessive doses may precipitate renal failure. Dextran may interfere to some extent with platelet function and should be used with caution in cases with thrombocytopenia. Transient prolongation of bleeding time and/or slightly increased bleeding tendency may occur with the administration of doses greater than 1,000 mL. Care should be taken to prevent a depression of hematocrit below 30% by volume. When large volumes of dextran are administered, plasma protein levels will be decreased. Solutions containing sodium ions should be used with great care, if at all, in patients with congestive heart failure, severe renal insufficiency and in clinical states in which there exists edema with sodium retention. The intravenous administration of this solution can cause fluid and/or solute overloading resulting in dilution of serum electrolyte concentrations, overhydration, congested states or pulmonary edema. The risk of dilutional states is inversely proportional to the electrolyte concentrations of administered parenteral solutions. The risk of solute overload causing congested states with peripheral and pulmonary edema is directly proportional to the electrolyte concentrations of such solutions. In patients with diminished renal function, administration of solutions containing sodium ions may result in sodium retention.