Intraoperative bronchial aspiration of ruptured pulmonary hydatid cysts. Ruptured pulmonary hydatid cysts are seen clinically and radiologically as persistent cavitary lesions of the lung. Bronchi opening into the pericyst cavity allow for discharge of fluid matter but not the escape of solid remnants of the collapsed parasite. Operative manipulation of the involved lung in the course of surgical management of chronic ruptured pulmonary hydatids can force fragments of the laminated membrane or small daughter cysts into the bronchial tree. Such extruded solid fragments lodge in bronchi of the same or opposite lung with resulting acute obstruction of airways. Intraoperative bronchial aspiration of hydatid material was seen in 7 patients with ruptured hydatid cysts of the lung, either primary or secondary to transdiaphragmatic extension of liver hydatids. The first clinical sign can be unexplained difficulty in ventilation. Effective management consists of prompt exposure of the stem bronchus on the operative side, with bronchotomy for suction retrieval of escaped solid fragments of the parasite. 