Elizabeth McLellan1, Karen Lam2, Elizabeth Behringer3, Vincent Chan4, Didem Bozak2, Nicholas Mitsakakis5, Anahi Perlas6. 1. Department of Anesthesia and Pain Management, Toronto Western Hospital, University Health Network, Toronto, ON, Canada; Royal Brisbane and Women's Hospital, Brisbane, Australia. 2. Department of Anesthesia and Pain Management, Toronto Western Hospital, University Health Network, Toronto, ON, Canada. 3. Department of Cardiovascular Surgery, Kaiser Permanente Los Angeles Medical Center, Los Angeles, CA, USA. 4. Department of Anesthesia, University of Toronto, Toronto, ON, Canada; Toronto Western Hospital, University Health Network, Toronto, ON, Canada. 5. Institute of Health Policy, Management and Evaluation, University of Toronto, Toronto, ON, Canada; Biostatistics Research Unit, University Health Network, Toronto, ON, Canada. 6. Department of Anesthesia, University of Toronto, Toronto, ON, Canada; Toronto Western Hospital, University Health Network, Toronto, ON, Canada. Electronic address: Anahi.perlas@uhn.ca.
Abstract
BACKGROUND: High-flow, heated, and humidified nasal oxygen therapy (HFNO) is frequently used in critical care and perioperative settings for a range of clinical applications. Much of the benefit of HFNO is attributed to generation of modest levels of positive airway pressure. Concern has been raised that this positive airway pressure may cause gastric insufflation, potentially increasing the risk of regurgitation and aspiration in an unprotected airway. METHODS: A prospective, interventional, assessor-blinded study was undertaken to evaluate the effects of HFNO on gastric content and gastric distension in healthy fasted adult volunteers assessed by ultrasonography. The primary outcome was the volume of gastric secretions. The secondary outcomes were the incidence of gastric air insufflation and the distribution of gastric antral grades. RESULTS: Sixty subjects were enrolled. No subject was found to have air gastric distension either at baseline or after treatment with HFNO. All subjects had either a Grade 0 or Grade 1 antrum, with similar distribution of antral grades and similar volume of gastric secretions before and after treatment with HFNO. CONCLUSIONS: There was no evidence that treatment with HFNO at flow rates of up to 70 L min-1 for 30 min resulted in gastric distension or an increase in gastric secretions in healthy individuals breathing spontaneously. The generalisability of these findings to subjects under anaesthesia and patients with incompetence of the lower oesophageal sphincter or impaired gastric emptying requires further investigation. CLINICAL TRIAL REGISTRATION: NCT03134937.
BACKGROUND: High-flow, heated, and humidified nasal oxygen therapy (HFNO) is frequently used in critical care and perioperative settings for a range of clinical applications. Much of the benefit of HFNO is attributed to generation of modest levels of positive airway pressure. Concern has been raised that this positive airway pressure may cause gastric insufflation, potentially increasing the risk of regurgitation and aspiration in an unprotected airway. METHODS: A prospective, interventional, assessor-blinded study was undertaken to evaluate the effects of HFNO on gastric content and gastric distension in healthy fasted adult volunteers assessed by ultrasonography. The primary outcome was the volume of gastric secretions. The secondary outcomes were the incidence of gastric air insufflation and the distribution of gastric antral grades. RESULTS: Sixty subjects were enrolled. No subject was found to have air gastric distension either at baseline or after treatment with HFNO. All subjects had either a Grade 0 or Grade 1 antrum, with similar distribution of antral grades and similar volume of gastric secretions before and after treatment with HFNO. CONCLUSIONS: There was no evidence that treatment with HFNO at flow rates of up to 70 L min-1 for 30 min resulted in gastric distension or an increase in gastric secretions in healthy individuals breathing spontaneously. The generalisability of these findings to subjects under anaesthesia and patients with incompetence of the lower oesophageal sphincter or impaired gastric emptying requires further investigation. CLINICAL TRIAL REGISTRATION: NCT03134937.
Authors: Weiqing Jiang; Li Shi; Qian Zhao; Wenwen Zhang; Man Xu; Wanling Wang; Xiaoliang Wang; Hongguang Bao; Jing Leng; Li Jiang Journal: Nan Fang Yi Ke Da Xue Xue Bao Date: 2020-11-30
Authors: Hye Jin Kim; Min-Soo Kim; So Yeon Kim; In Kyung Min; Wyun Kon Park; Sei Han Song; Dongkwan Shin; Hyun Joo Kim Journal: Sci Rep Date: 2022-07-04 Impact factor: 4.996