Removal of 144Ce in Fused Clay Particles from the Beagle Dog Lung by Bronchopulmonary Lavage

Abstract

The effectiveness of repeated bronchopulmonary lavage for removing inhaled l4We fused clay particles from the lungs of Beagle dogs was investigated. Twelve Beagle dogs were exposed to a 144Ce fused clay aerosol resulting in initial lung burdens ranging from 47-64 pCi/kg body weight. Eight received 10 saline lavage treatments, five on each lung over a 56-day period. At the end of each lavage, they also received 50 mg of calcium diethylenetriaminepentaacetic acid (DTPA) intravenously. Four dogs received no treatment. A second group of four dogs was exposed to an aeorsol of fused clay only and given 10 lung lavages over a 56-day period. I n the eight treated dogs, an average of 44% of initial lung burden was removed by the 10 lavage procedures. Recovery from two of these eight dogs was considerably lower, 23 and 27%, than the average of the remaining 6, 51%. The reason for this has not been established. Examination of the urinary excretion showed that although the DTPA injections increased urinary excretion 10 fold, this difference between the treated and untreated dogs accounted for only 1.6% of the initial lung burden. Thus, for 144Ce inhaled in this form, the lavage procedure was 28 times more effective in removing '44Ce from the body than were the DTPA injections. The reduction in initial lung burden over a 56-day treatment period resulted in a decrease of the cumulative radiation dose to the lung, at 90 days and infinity, to 53 and 57%, respectively, of that found for the untreated dogs. No significant clinical changes due to treatment were observed in these animals. All of the dogs in this study were alive at 90 days post-exposure and are now under observation in the colony.

Effect of bronchopulmonary lavage on lung retention and clearance of particulate material in hamsters.

“…The technique has been extensively studied in baboons, dogs, and rodents as a possible treatment to reduce lung deposits of insoluble radioactive particles after inhalation (5)(6)(7)(8)(9)(10)(11). For example, Brightwell and Ellender (6) found that repeated lavage ofhamsters during the first 4 weeks after inhalation ofplutonium dioxide (PU02) removed 90% ofthe initial lung burden.…”

Effect of Time Post-exposure on the Effectiveness of Bronchopulmonary Lavage in Removing Inhaled 144Ce in Fused Clay from Beagle Dogs

“…I n previous studies in which dogs were given a series of lavages after they inhaled relatively insoluble aerosols of 144Ce in fused clay, the fraction of the lung burden removed in the lavage fluid tended to decrease with each succeeding lavage (BOECKER et al, 1974;SILBAUCH et al, 1975). For example, unilateral lavage of the right lung in eight dogs at 2,9 and 21 days after exposure removed mean fractions of 16, 5.5 and 2.5%, respectively, of the initial lung burden (BOECKER et al, 1974).…”

“…For example, unilateral lavage of the right lung in eight dogs at 2,9 and 21 days after exposure removed mean fractions of 16, 5.5 and 2.5%, respectively, of the initial lung burden (BOECKER et al, 1974). These decreases could have been due to either the increasing time after exposure or the reduction of the lung burden with each lavage.…”

“…BRONCHOPULMONARY lavage (lung washing) has been used to remove inhaled radioactive particles from the lungs of man (MCCLELLAN et al, 1972) and experimental animals (BOECKER et al, 1974;SILBAUGH et al, 1975). The factors which limit removal of the radioisotope by this treatment are not well understood but the time after exposure at which lavage is performed may be important.…”

Effect of Flow Rate of Lavage Fluid on the Removal of Radioactive Particles from the Lung by Bronchopulmonary Lavage

“…Lavage has also been used to remove radioactive particles from the lung in man and in experimental animals (PFLEGER et al, 1969;KUNGLE-LUTZ et at., 1970;BOECKER et al, 1974). I n clinical practice, lavage is usually performed on one side of the lung per session.…”