Heparin via the lung

Only recently has it been realized that heparin is absorbed when administered into the lung. Im mice, rats, dogs and humans a large dose of intrapulmonary heparin has been shown to cause a moderate degree of hypocoagulability lasting from 48 hours to 14 days depending on the species. This study is part of an ongoing program investigating the effects of the intrapulmonary administration of heparin. Heparin, 1500 units/kg body weight was instilled into the lung in a group of 12 dogs and an equal volume of saline was given in a control group of 10 dogs. Various hemodynamic and metabolic measurements were made at intervals. As expected there was a prolonged moderate increase in clotting time, but no significant effects from intrapulmonary administration of heparin were demonstrated by any of the other measurements. Much work has yet to be done before intrapulmonary heparin can be used clinically but it has potential importance in the management of thromboembolic disease.