The Questionable Efficacy of Topical Pharyngeal Anesthesia in Combination with Propofol Sedation in Gastroscopy Digestive Diseases and Sciences (2012) 57:2519-2526 Hsin-I Tsai ‧ Yung-Fung Tsai ‧ Shiue-Chin Liou ‧ Ming-Yao Su ‧ Chih-Chung Lin ‧ Chee-Jen Chang ‧Huang-Ping Yu