title: The effect of mechanically-induced cricoid force on lower oesophageal sphincter pressure in anaesthetised patients.
abstract: In the United Kingdom, cricoid force is central to upper airway management in obstetric and emergency anaesthesia. A reduction in oesophageal barrier pressure (OBP) in these patients may increase regurgitation risk. This study investigated whether the application of cricoid force to anaesthetised patients reduced lower oesophageal sphincter pressure (LOSP) and consequently OBP. Anaesthesia was induced in 29 patients using a standard protocol. An oesophageal balloon catheter was inserted and gastric trace identified. The catheter was withdrawn incrementally and pressure readings recorded at each position before and during the application of 30 N cricoid force, with a sudden rise in pressure indicating lower oesophageal sphincter position. Oesophageal barrier pressure was calculated as the difference between LOSP and gastric pressure. Application of cricoid force significantly reduced OBP without influencing gastric pressure (p < 0.001). The use of cricoid force may increase the risk of gastroesophageal reflux in anaesthetised patients.
authors.affiliation: Department of Anaesthetics and Intensive Care Medicine, University Hospital of Wales, Cardiff, UK.
authors.forename: A
authors.initials: A
authors.lastname: Garrard
authors.forename: A E
authors.initials: AE
authors.lastname: Campbell
authors.forename: A
authors.initials: A
authors.lastname: Turley
authors.forename: J E
authors.initials: JE
authors.lastname: Hall
mesh_terms: D000328:Adult; D000368:Aged; D000768:Anesthesia, General; D003413:Cricoid Cartilage / Q000502:physiology*; D004943:Esophagogastric Junction / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011015:Pneumonia, Aspiration / Q000517:prevention & control; D011312:Pressure; D013270:Stomach / Q000502:physiology; D013314:Stress, Mechanical