Dextran

Dextran is a low molecular weight dextran used as an adjunctive treatment of shock or impending shock due to hemorrhage, burns, surgery or other trauma, as well as the prophylaxis of venous thrombosis and pulmonary embolism during high-risk medical procedures[1]. It is a polysaccharide that differs from others in that its glucose units are joined together 1:6 glucoside links[1]. The main chain of glucose has short branches at frequent intervals which are probably joined by 1:3 and 1:4 glucoside links[1]. The chains can be composed of about 200,000 glucose units[1]. Many bacteria, like Leuconostoc, can synthesize dextran from sucrose, and this activity is used commercially to obtain dextran[1].

Dextran 40 is a sterile, nonpyrogenic preparation of low molecular weight dextran (average mol. wt. 40,000) in 5% Dextrose Injection or 0.9% Sodium Chloride Injection[1]. It is administered by intravenous infusion[1]. Dextran 75 is a complex branched glucan with an average molecular weight 75000 Daltons[1]. It is produced from certain bacteria that with α-1,6 glycosidic linkages between glucose molecules and α-1,3 linkages between branches[1]. When labelled with technetium Tc99m, dextran 75 is intravenously administered as an imaging agent to detect and diagnose conditions in the vascular compartment such as pericardial effusion or ventricular aneurysm[1].

Dextran is used as the restoration of blood mass during surgical interventions if there is hypovolemia due to trauma or dehydration[1]. It is as well used after the presence of hemorrhage in cases of blood loss to a level inferior to 15% of the blood mass, if compatibility test cannot be completed or when blood lots need to be tested for pathogen detection[1]. Dextran is also used for the prevention of profound postoperative venous thrombosis[1]. Dextran as well presents ophthalmic applications as solutions or ointments for the temporary relief of xerophthalmia or minor ocular irritations[1].

Dextran is a complex branched glucan (polysaccharide derived from the condensation of glucose), originally derived from wine[2]. IUPAC defines dextrans as "Branched poly-α-d-glucosides of microbial origin having glycosidic bonds predominantly C-1 → C-6"[2]. Dextran chains are of varying lengths (from 3 to 2000 kilodaltons)[2]. The polymer main chain consists of α-1,6 glycosidic linkages between glucose monomers, with branches from α-1,3 linkages[2]. This characteristic branching distinguishes a dextran from a dextrin, which is a straight chain glucose polymer tethered by α-1,4 or α-1,6 linkages[2].

Dextran 70 is on the WHO Model List of Essential Medicines, the most important medications needed in a health system[2]. Medicinally it is used as an antithrombotic (antiplatelet), to reduce blood viscosity, and as a volume expander in hypovolaemia[2]. Dextrans are available in multiple molecular weights ranging from 3 kDa to 2 MDa[2]. The larger dextrans (>60,000 Da) are excreted poorly from the kidney, so remain in the blood for as long as weeks until they are metabolized[2]. Consequently, they have prolonged antithrombotic and colloidal effects[2]. In this family, dextran-40 (MW: 40,000 Da), has been the most popular member for anticoagulation therapy[2]. Close to 70% of dextran-40 is excreted in urine within the first 24 hours after intravenous infusion, while the remaining 30% are retained for several more days[2].

Dextran is used in managing and treating various clinical conditions, including during hemorrhage, shock, surgical procedures, radiological imaging, antithrombotic administration, and ophthalmic relief of xerophthalmia[3]. This activity reviews the indications, contraindications, adverse events, mechanisms of action, toxicity, and other key factors of dextran therapy in the clinical setting related to the essential information needed by members of a healthcare team[3].

LMD (dextran 40) is indicated for use in the adjunctive treatment of shock or impending shock due to hemorrhage, burns, surgery or other trauma[4]. It is not indicated as a replacement for whole blood or blood components if they are available[4]. It should not replace other forms of therapy known to be of value in the treatment of shock[4]. LMD is also indicated for use as a priming fluid, either as a sole prime or as an additive, in pump oxygenators during extracorporeal circulation[4].

Dextran is a high molecular weight glucose polymer produced by the action of the bacteria, Leuconostoc mesenteroides , on a sucrose substrate[5]. It is used in various cosmetic products, including serums and essences, facial moisturizers, hair treatments, mascaras, masks, around-eye creams, shampoos, anti-aging products, and more[5]. However, it is restricted in EWG VERIFIED products without adequate substantiation[5].

Citations:

[1] https://go.drugbank.com/drugs/DB09255

[2] https://en.wikipedia.org/wiki/Dextran

[3] https://www.ncbi.nlm.nih.gov/books/NBK557631/

[4] https://www.pfizermedicalinformation.com/dextran

[5] https://www.ewg.org/skindeep/ingredients/701898-DEXTRAN/