The effect of mechanically‐induced cricoid force on lower oesophageal sphincter pressure in anaesthetised patients

Abstract

SummaryIn 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 The catheter was withdrawn incrementally and pressure readings recorded at each position before and during the application of 30 N cricoid force, with a sudden rise in pressure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.

Cricoid Pressure Provides Incomplete Esophageal Occlusion Associated with Lateral Deviation: A Magnetic Resonance Imaging Study

“…First, using an anatomical assessment as an endpoint is more easily achieved, but does not replace the need to perform some type of functional study. This would be required to determine the risk of potential adverse effects of CP, including the reduction of lower esophageal sphincter tone that may accompany CP (15). Therefore, the functional significance of incomplete or ineffective esophageal occlusion observed in our cohort cannot be determined.…”

“…Medical interventions should, where possible, be evaluated according to the risk-benefit ratio for the patient or population in question. Risks associated with CP include esophageal rupture cricoid injury, disturbance of an unstable cervical spine, impaired laryngeal view at intubation, and difficult ventilation and potential decrease in lower esophageal sphincter tone (10,14,15). Thus, CP has not been clearly established as a means to reduce the risk of aspiration of gastric contents in live patients, but it has been associated with increased risk to patients.…”

S1 guidelines on airway management

“…Some publications, for example indicate that cricoid pressure is frequently incorrectly applied [85] so that a reliable closure of the esophagus by cricoid pressure cannot regularly be achieved [86,87] and muscle tone of the lower esophagus sphincter can be reduced by the maneuver [88]. In addition, the application of cricoid pressure can impede mask ventilation as well as direct and even indirect laryngoscopy [89].…”

A cricoid cartilage compression device for the accurate and reproducible application of cricoid pressure

“…With the exception of one favourable published abstract [15], there have been no randomised, controlled trials to assess the benefits and/or risks of using this technique. Ironically, there has been a raft of contra-indicatory findings that cricoid pressure may not even prevent regurgitation [16,17], and may actually induce nausea and vomiting [18], promote aspiration by relaxing the lower oesophageal sphincter [3,19,20], impede airway management [21,22], prolong intubation time by obscuring the laryngeal view [23,24]; and possibly lead to cricoid cartilage fracture [25] and/or oesophageal rupture [2,24] by the application of excessive force. Despite this negativity [26], there still seems to be a wide body of acknowledged medical and legal approval [5,7,27] for using this technique in order to reduce patient risk.…”