Background: Obese patients often present difficulties with face mask ventilation during general anaesthesia (GA) induction. A nasal mask assembly has been shown to maintain oxygenation in sedated obese OSA patients and to improve ventilation in anaesthetized patients with poor face-mask fit.1-3 We presented its use in an obese patient with a difficult airway.. 
Case report: A 65 y/o obese (BMI 34 kg/m2) female with metastatic lung cancer to the brain, s/p chemotherapy and radiation therapy presented for bronchoscopy to evaluate hemoptysis. CTA revealed a large right hilar mass (8.5 cm) encased pulmonary artery and mainstem bronchus. 
She had a full round face, Class III airway, poor dentition, a large tongue and suspected OSA. She gave consent to use a nasal mask for GA induction and for photography/case report. An infant mask (size #2) with fully inflated air cushion was secured over her nose with head straps and connected to a breathing circuit with 6 L/min O2 and 5-6 cm H2O CPAP delivered through anaesthesia machine. Her O2 saturation (Sat) increased to 100% from 93%. GA was induced with fentanyl and propofol. Her mouth was closed and a tight nose-mask seal was obtained with one hand and positive pressure ventilation was easy with the other hand. Succinylcholine was then given. With the nasal mask assembly providing apneic oxygenation, endotracheal intubation (ETI) was performed using a video-laryngoscope (VL). Her O2 Sat was 100% throughout ETI. Bronchoscopy revealed active arterial bleeding in the right main bronchus requiring urgent endovascular embolization. She was placed in the right lateral decubitus position. Left radial arterial catheter was inserted to monitor blood pressure. She was stabilized and transported to Interventional Radiology Suite for bronchial artery embolization. She tolerated the procedure well without any complications and bleeding was successfully controlled. 

Discussion: This nasal mask assembly provided continuous oxygenation in an obese patient with a difficult airway and poor face-mask fit during GA induction and VL ETI. It prevented severe desaturation and may have improved patient safety.
Ref: 1. SAMBA 28th AM, March 2013; 2. www.TSEMask.com; 3. ASA AM (MC3009), Oct 2015 
Learning Points: How to provide nasal CPAP preoxygenation in obese OSA patients, assisted nasal ventilation in anaesthetized patients with poor face-mask fit by one anaesthesiologist and continuous apnoeic oxygenation during VL ETI.

A novel nasal mask assembly provided CPAP pre-oxygenation, positive pressure ventilation and apnoeic oxygenation during general anaesthesia induction in an obese patient with suspected OSA, difficult airway and poor face-mask fit during Bronchoscopy