Where Is the Convex-Probe Endobronchial Ultrasound Balloon? A Lessen to Learn
Endobronchial ultrasound (EBUS)-guided transbronchial needle aspiration (TBNA) is a minimally invasive bronchoscopic procedure with overall complication rate <1.5%.1 The complications of EBUS-TBNA such as needle fracture and retention within the lymph nodes,2 pneumothorax, airway bleeding requiring intervention, mediastinitis, and hypoxic respiratory failure have been reported in the literature.1 We describe a case of dislodged convex-probe EBUS balloon in the bronchus. Its pathophysiologic mechanism, and preventive measures are also discussed. If such a complication is unrecognized, it could lead to life-threatening consequences.
A 71-year-old woman underwent right upper lobectomy for stage IB squamous cell lung carcinoma followed by 4 cycles of chemotherapy. Surveillance computed tomography of the chest 6 months later demonstrated an enlarged right paratracheal lymph node (station 4R) measuring 18×13 mm in size. EBUS-TBNA was performed to determine tumor recurrence in the mediastinum. She underwent general anesthesia with endotracheal tube placement because of difficulty placing the laryngeal mask airway. A flexible bronchoscopy was initially advanced through the endotracheal tube to determine the airway anatomy and no endobronchial lesion was found. The tip of the endotracheal tube was just 1 cm above the carina and was withdrawn a couple of centimeters to allow access to the right paratracheal node. The EBUS balloon had to be inflated to establish a firm contact with the airway mucosa overlying the right paratracheal lymph node for obtaining adequate ultrasonic visualization of the node. Multiple TBNA were obtained while the endotracheal tube remained slightly above the tip of the EBUS bronchoscope. Rapid on-site evaluation of the specimens demonstrated the presence of squamous cell carcinoma confirming the diagnosis of tumor recurrence. The EBUS scope was advanced to the left hilar area for lymph node evaluation; however, the balloon inflation was not successful because the small crescent of the balloon usually seen on the fiber-optic image was not identified. The EBUS scope was withdrawn to evaluate the balloon, which was not found at the tip of the scope. Airway inspection using the flexible bronchoscope showed a foreign body at the orifice of the right lower lobe bronchus (Fig. 1). It was identified to be the dislodged balloon of the EBUS scope and was successfully retrieved using suction.
Our explanation of this occurrence is that the balloon attached to the probe was rubbing against the endotracheal tube during right paratracheal node aspirations forcing the balloon to slip from the probe to the right lower lobe bronchus. If the EBUS scope is removed without attempting to inflate the balloon to visualize the left hilar nodes, the balloon could be left in the airways, which could have led to complications such as atelectasis and postobstructive pneumonia. It is important to confirm the presence of the balloon at the end of the EBUS procedure and to recognize that balloon migration to the airways can lead to potential complications if it goes unnoticed. Laryngeal mask airway instead of endotracheal tube for ventilation during the EBUS procedure, particularly for higher paratracheal lymph node aspiration, may prevent the occurrence of this complication.3 One can certainly argue that use of conventional-TBNA for 18×13 mm lymph node at the 4R location in a patient with recurrent lung cancer could have certainly avoided the mishap.