Dextran 40 + Sodium Chloride

Usage

• Dextran 40 + Sodium Chloride is prescribed for adjunctive therapy in hypovolemic shock caused by hemorrhage, burns, surgery, or trauma. It is also used for prophylaxis of thromboembolic events (such as deep vein thrombosis and pulmonary embolism), particularly in surgical settings like hip surgery. It can be used in extracorporeal circulation as a priming fluid in pump oxygenators.

• Pharmacological Classification: Plasma volume expander, antithrombotic.

• Mechanism of Action: Dextran 40 increases the osmotic pressure of the plasma, drawing fluid from the interstitial space into the vascular compartment. This expands plasma volume and improves blood flow. Its antithrombotic action is related to reduced blood viscosity, decreased platelet adhesiveness, and red blood cell aggregation.

Alternate Names

• Low Molecular Weight Dextran (LMD) in Sodium Chloride.
• Dextran 40 in 0.9% Sodium Chloride Injection.
• Brand Names: Gentran 40 with 0.9% Sodium Chloride, LMD with 0.9% Sodium Chloride, Polifleks.

How It Works

• Pharmacodynamics: Dextran 40 expands plasma volume, improves microcirculation, and reduces blood viscosity. It can also affect blood coagulation parameters like bleeding time and platelet function.
• Pharmacokinetics: Administered intravenously, Dextran 40 is primarily excreted renally. Smaller dextrans are rapidly filtered by the glomeruli, while larger ones are metabolized by plasma and tissue enzymes. Elimination half-life varies depending on the molecular weight of the dextran fraction.
• Mode of Action: Dextran 40 exerts its effect through increasing the colloid osmotic pressure of plasma, which leads to intravascular volume expansion. Dextran 40 decreases red blood cell aggregation, lowers platelet adhesiveness, and inhibits alpha-2-antiplasmin.
• Receptor Binding, Enzyme Inhibition or Neurotransmitter Modulation: Not applicable in the classic sense. Effects are mediated by the changes in fluid dynamics and blood properties.
• Elimination Pathways: Primarily renal excretion; some metabolic breakdown by plasma and tissue enzymes.

Dosage

Standard Dosage

Adults:

• Shock: Initial dose: 10 mL/kg (1 g/kg) by rapid infusion. Maximum dose: 20 mL/kg (2 g/kg) in the first 24 hours. Subsequent doses (if needed): Up to 10 mL/kg (1 g/kg) daily for a maximum of 5 days.
• Thromboembolism Prophylaxis: 500-1000 mL (approximately 10 mL/kg or 50-100 g) on the day of surgery, followed by 500 mL (50 g) daily for 2-3 days. Subsequent doses: 500 mL (50 g) every 2-3 days for up to 2 weeks, depending on the risk.

Children:

• Infants: 0.5 g/kg (5 mL/kg).
• Children: 1 g/kg (10 mL/kg).
• Adolescents: Follow adult dosing guidelines.
• Pediatric Safety Considerations: Safety and efficacy not fully established in neonates. Limited use in neonates requires careful consideration of dosage and potential adverse effects.

Special Cases:

• Elderly Patients: Monitor closely for fluid overload and renal function.
• Patients with Renal Impairment: Reduce dosage or avoid use in severe renal failure with oliguria or anuria.
• Patients with Hepatic Dysfunction: Exercise caution and monitor closely.
• Patients with Comorbid Conditions: Use with caution in patients with heart failure, pulmonary edema, active hemorrhage, diabetes mellitus, chronic liver failure.

Clinical Use Cases

• Intubation, Surgical Procedures, Mechanical Ventilation, ICU Use: Dextran 40 can be utilized for volume expansion and maintenance as needed within the dosage guidelines.
• Emergency Situations: For shock, initiate with a rapid infusion of 10 mL/kg (1 g/kg), up to a maximum of 20 mL/kg (2 g/kg) in the first 24 hours. Monitor closely.

Dosage Adjustments:

• Adjust dose based on clinical response, fluid status, and laboratory findings. Individualized adjustments may be required in cases of renal or hepatic dysfunction.

Side Effects

Common Side Effects:

• Fluid overload.
• Nausea, vomiting.
• Joint pain.
• Mild hypotension.
• Increased bleeding tendency.
• Abnormal renal and hepatic function test values.

Rare but Serious Side Effects:

• Severe anaphylactoid reactions (hypotension, cardiac arrest, respiratory arrest).
• Acute renal failure.
• Pulmonary edema.

Long-Term Effects: Not well-defined.

Adverse Drug Reactions (ADR): Anaphylaxis requires immediate discontinuation and intervention.

Contraindications

• Hypersensitivity to dextran.
• Marked hemostatic defects (e.g., thrombocytopenia, hypofibrinogenemia).
• Marked cardiac decompensation.
• Renal disease with severe oliguria or anuria.

Drug Interactions

• Additive medications should not be administered via dextran solutions.
• May potentiate bleeding with anticoagulants (e.g., warfarin, heparin, apixaban, rivaroxaban, enoxaparin).

Pregnancy and Breastfeeding

• Pregnancy Safety Category: C. Animal reproduction studies have not been conducted. Use only if clearly needed.
• Breastfeeding: Excretion in human milk unknown. Exercise caution.

Drug Profile Summary

• Mechanism of Action: Plasma volume expansion, reduced blood viscosity and erythrocyte aggregation.
• Side Effects: Fluid overload, bleeding, anaphylaxis (rare).
• Contraindications: Hypersensitivity, severe bleeding disorders, cardiac decompensation, renal failure with oliguria/anuria.
• Drug Interactions: Anticoagulants.
• Pregnancy & Breastfeeding: Use cautiously if benefits outweigh risks.
• Dosage: Adults: 10-20 mL/kg/day (shock); 500-1000 mL initially then 500 mL daily, then every 2-3 days (thromboembolism prophylaxis). Dosage modifications based on individual needs.
• Monitoring Parameters: Hemodynamic parameters (BP, heart rate, CVP), renal function, coagulation status, signs of fluid overload.

Popular Combinations: Often used as a sole agent for volume expansion.

Precautions

• Monitor closely for signs of circulatory overload, bleeding, and renal function. Dextran 1 should be administered before Dextran 40 to reduce the risk of anaphylactic reactions.

FAQs (Frequently Asked Questions)

Q1: What is the recommended dosage for Dextran 40 + Sodium Chloride?

A: Refer to the detailed dosage guidelines outlined in the dosage section above, as it depends on the clinical indication and patient-specific factors.

Q2: What are the most common side effects?

A: Fluid overload, nausea, vomiting, joint pain, and altered bleeding time are among the more commonly observed side effects.

Q3: What are the contraindications to using Dextran 40?

A: Hypersensitivity to dextran, marked hemostatic defects, severe cardiac decompensation, and renal failure with anuria/oliguria contraindicate the drug’s use.

Q4: How does Dextran 40 work in the body?

A: Dextran 40 expands plasma volume through its colloidal osmotic effects, reduces blood viscosity, and improves microcirculation.

Q5: Can Dextran 40 be used during pregnancy?

A: Dextran 40 should be used during pregnancy only if the potential benefit justifies the potential risk to the fetus.

Q6: Are there any drug interactions with Dextran 40 + Sodium Chloride?

A: Concomitant use with anticoagulants may increase the risk of bleeding. Avoid adding other medications to dextran solutions.

Q7: What monitoring parameters are important when administering Dextran 40?

A: Vital signs (BP, heart rate), central venous pressure, urine output, renal and hepatic function tests, and coagulation parameters are crucial for monitoring during and after administration.

Q8: How is Dextran 40 administered?

A: Dextran 40 is administered via intravenous infusion. Pre-administration of Dextran 1 is recommended to reduce allergic reaction potential.

Q9: What is the difference between Dextran 40 and Dextran 70?

A: Both are plasma expanders, but Dextran 70 has a higher molecular weight. Dextran 40 is preferred for shock, whereas Dextran 70 is more commonly used for thromboembolism prophylaxis.

Q10: What should be done if a patient experiences an anaphylactic reaction?

A: Immediately discontinue the infusion and provide appropriate supportive care, which may include epinephrine, antihistamines, and oxygen.