Nasal breathing is superior to oral breathing when performing and undergoing transnasal endoscopy: a randomized trial

Abstract

Background and study aims: Transnasal endoscopy presents a technical difficulty when inserting the flexible endoscope, and it is unclear whether a particular breathing method is useful for transnasal endoscopy. Therefore, we conducted a prospective randomized controlled trial to compare endoscopic operability and patient tolerance between patients in the nasal breathing and oral breathing groups. Patients and methods: A total of 198 eligible patients were randomly assigned to undergo the transnasal endoscopy with nasal breathing and with oral breathing. Endoscopists and patients answered questionnaires on the endoscopic operability and patient tolerance using a 100-mm visual analog scale ranging from 0 (non-existent) to 100 (most difficult/ unbearable). The visibility of the upper-middle pharynx was recorded. Results: Patient characteristics didn’t differ significantly in both groups. Nasal breathing showed a higher rate of good visibility of the upper-middle pharynx than oral breathing (91.9% vs. 27.6%; p<0.05). Nasal breathing showed lower scores than oral breathing in overall technical difficulty (21.0±11.4 vs. 35.4±15.0; p<0.05). Regarding patient tolerance, nasal breathing showed lower scores than oral breathing in overall discomfort (22.1±18.8 vs. 30.5±20.9; p<0.05) and other symptoms, including nasal and throat pain, choking, suffocating, gagging, belching, and bloating (p<0.05). Pharyngeal bleeding rate was lower in the nasal breathing group than that in the oral breathing group (0% vs. 9.2%; p<0.05). Conclusions: Nasal breathing is superior to oral breathing in performing and undergoing transnasal endoscopy. Nasal breathing led to good visibility of the upper-middle pharynx, improved endoscopic operability and patient tolerance, and showed safety by decreasing pharyngeal bleeding.