Prevention of radiation pneumonitis from inhaled 144Ce in beagle dogs by bronchopulmonary lavage

The efficacy of bronchopulmonary lavage and chelation therapy to remove 144Ce inhaled in fused clay particles and prevent radiation pneumonitis was evaluated in dogs. Sixteen beagle dogs were divided into three groups. Eight dogs (Group 1) were treated with a series of 10 bronchopulmonary lavages and 10 injections of diethylenetriaminepentaacetic acid during the first 56 days after inhalation exposure to 144Ce in fused clay particles. As a result of treatment, 46 percent of the initial lung burden of 144Ce was removed and six of eight dogs survived to 550 days after exposure. Four dogs (Group II) were exposed by inhalation to 144Ce but were not treated. One dog survived to 550 days after exposure. Nonsurvivors in both groups died of radiation pneumonitis 170 to 240 days after exposure. The remaining four dogs were not exposed to 144Ce but were given the lavage treatment; all survived to 550 days. (U.S.)