Lung Lavage Therapy to Lessen the Biological Effects of Inhaled 144 Ce in Dogs

Abstract

To evaluate the therapeutic effects of removal of an internally deposited radionuclide on long-term biological effects, lung lavage was used to treat dogs that had inhaled 144Ce in a relatively insoluble form, in fused aluminosilicate particles. Either 10 lung lavages were performed between Days 2 and 56 after exposure or 20 lung lavages were performed between Days 2 and 84 after exposure. Approximately one-half of the 144Ce was removed by the lavages, resulting in a corresponding reduction in the total absorbed beta dose to lung. The mean survival time of the treated dogs was 1270 days compared to 370 days for untreated dogs whose initial pulmonary burdens of 144Ce were similar. Treated dogs died late from cancers of the lung or liver, whereas the untreated dogs died at much earlier times from radiation pneumonitis. Dogs treated with lung lavage but not exposed to 144Ce had a mean survival of 4770 days. We concluded that removal of 144Ce from the lung by lavage resulted in increased survival time and in a change in the biological effects from inhaled 144Ce from early-occurring inflammatory disease to late-occurring effects, principally cancer. In addition, the biological effects occurring in the treated dogs could be better predicted from the total absorbed beta dose in the lung and the dose rate after treatment rather than from the original dose rate to the lung. Therefore, we concluded that prompt treatment to remove radioactive materials could be of significant benefit to persons accidentally exposed to high levels of airborne, relatively insoluble, radioactive particles.

Radiation mitigating properties of the lignan component in flaxseed

“…Lung lavage has been advocated as a possible countermeasure to remove radionuclides inhaled after detonation of an RDD [39,40]. However, this seems impractical since multiple lavages may be required for efficient removal of radionuclide burden using an invasive procedure with inherent risks and a requirement of anesthesia.…”

Dietary flaxseed administered post thoracic radiation treatment improves survival and mitigates radiation-induced pneumonopathy in mice

“…Some reports suggest using lung lavage to remove radionuclides inhaled after a dirty bomb detonation as a possible countermeasure [28,29]. However, this remains an impractical countermeasure since multiple lavages may be required for efficient removal of radionuclide burden while the procedure itself is associated with known risks of an invasive procedure that requires anesthesia.…”

Development and Licensure of Medical Countermeasures to Treat Lung Damage Resulting from a Radiological or Nuclear Incident

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