A 55 year old Chinese male presented to the respiratory clinic for chronic cough for 3 weeks duration associated with haemoptysis. Prior to presentation, he was treated in the community with oral antibiotics without improvement. He had no known past medical history and but he had a significant 20 pack year smoking history. There were no relevant contact exposure or other symptoms to suggest pulmonary tuberculosis. A chest radiograph showed a large right lower zone mass, concerning for malignancy. A computed tomography (CT) thorax confirmed a right middle lobe mass with multiple necrotic mediastinal lymph nodes and liver metastasis (Fig. 1a). Sputum acid fast bacilli (AFB) smears and tuberculosis polymerase chain reaction (TB PCR) were negative.
A bronchoscopy and endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) of the mediastinal lymph nodes was arranged. Initial pre-procedural examination was unremarkable and he was afebrile with normal vital signs and oxygen saturation of 99% on room air. The patient did not have any pre-procedure risk factors for apnoea such as obstructive sleep apnoea (OSA) or short neck. His BMI was 18.9. Topical xylocaine spray 10% was given intra-orally and intra-nasally. Initial 1 mg of intravenous (IV) midazolam and 25 mug of IV fentanyl was given for moderate sedation with cardiac and pulse oximeter monitoring. A flexible bronchoscope was first introduced for airway inspection. Vocal cords was normal in appearance. Except for submucosal infiltration seen in the right middle lobe, there were no other endobronchial lesions seen (Fig. 1b). During inspection, a further 2 mg of IV midazolam was given to maintain adequate sedation. Bronchoalveolar lavage was performed to the right middle lobe with good returns. The flexible bronchoscope was removed and endobronchial ultrasound bronchoscope was introduced. Surveillance endobronchial ultrasound screen showed enlarged sub-carinal and right para-tracheal lymph nodes. Because the patient became agitated, a further IV midazolam 2 mg and IV fentanyl 25 mug was given, closely titrated to maintain moderate sedation. Successful EBUS-TBNA to sub-carinal lymph node was performed. We then proceeded to biopsy the right para-tracheal lymph node but abandoned because patient turned restless again and required a further IV fentanyl 50 mug. 2 minutes later, patient became unconscious and apnoeic. He was rigid and his chest wall movement ceased During the apnoea phase, he had desaturated leading to sinus bradycardia on the cardiac monitor. Bronchoscope was immediately removed and bag-valve-mask ventilation was attempted but ineffective due to chest wall rigidity. 100 mg IV suxamethonium was given for muscle paralysis to allow for endotracheal intubation and ventilation, followed by naloxone and flumazenil to reverse the effects of fentanyl and midazolam respectively. The time interval between the onset of apnoea and successful endotracheal intubation was 2 min. Airway inspection through the endotracheal tube showed no evidence of airway bleeding. Patient was extubated in the endoscopy room after 10 minutes of observation and wearing off of the effect of neuromuscular blockade (suxamethonium). He was closely observed in the recovery room for the next 6 hours during which he was successfully weaned off oxygen and discharged home on the same day.