Intrapulmonary heparin. A new procedure for anticoagulant therapy

Area of Science:

• Pharmacology
• Pulmonary Drug Delivery
• Hematology

Background:

• Heparin is a widely used anticoagulant.
• Conventional heparin administration routes have limitations.
• Intrapulmonary drug delivery offers potential for sustained release.

Purpose of the Study:

• To investigate the pharmacokinetic and safety profile of intrapulmonary heparin administration.
• To evaluate the anticoagulant effects and duration following intrapulmonary heparin.
• To explore the potential clinical utility of this novel administration route.

Main Methods:

• Heparin was administered via the intrapulmonary route to dogs, mice, and human volunteers.
• Clotting times were monitored to assess hypocoagulability.
• Postmortem examinations of lungs, body fluids, and tissues were conducted to evaluate safety.

Main Results:

• A single intrapulmonary dose of heparin induced a prolonged state of moderate hypocoagulability (3 days in dogs, 14 days in humans).
• The duration and intensity of the anticoagulant effect correlated with dosage, with effective doses exceeding 8 mg/kg.
• Heparin was rapidly cleared from the lungs, sequestered in cellular compartments (likely macrophages), and slowly released into plasma.
• No evidence of hemorrhage or heparin-related pathological changes was observed in any tissue or species.

Conclusions:

• Intrapulmonary heparin administration provides a sustained anticoagulant effect with a favorable safety profile.
• The unique pharmacokinetic profile suggests potential for novel anticoagulant therapies.
• Further clinical investigation into intrapulmonary heparin for anticoagulant treatment is warranted.