ABNORMALITIES ON VENTILATION-PERFUSION LUNG SCANS INDUCED BY BRONCHOALVEOLAR LAVAGE

Studies were performed before and at varying times after lavage in 10 normal volunteers to assess whether bronchoalveolar lavage results in significant abnormalities on ventilation/perfusion lung scans and ches t x-rays. Abnormal lung scans were obtained in six subjects, interpret able as intermediate (three scans), low (one scan) and very low (two s cans) probability for pulmonary emboli. Defects varied from multisegme ntal to subsegmental in size, while chest x-rays were normal in all bu t one. Both the extent and frequency of defects tended to decrease wit h time; 24 hr after bronchoalveolar lavage only one of four subjects h ad a minimally abnormal scan. It is recommended that ventilation/perfu sion lung scanning be delayed at least 24 hr following bronchoalveolar lavage to avoid problems in interpretation of defects which may merel y be the result of the lavage.