Hostname: page-component-7c8c6479df-fqc5m Total loading time: 0 Render date: 2024-03-28T02:52:30.478Z Has data issue: false hasContentIssue false

Cricoid yoke: the effect of surface area and applied force on discomfort experienced by conscious volunteers

Published online by Cambridge University Press:  02 June 2005

A. E. Campbell
Affiliation:
University of Wales College of Medicine, Department of Anaesthetics and Intensive Care Medicine, Cardiff, UK
A. Turley
Affiliation:
University of Wales College of Medicine, Department of Anaesthetics and Intensive Care Medicine, Cardiff, UK
A. R. Wilkes
Affiliation:
University of Wales College of Medicine, Department of Anaesthetics and Intensive Care Medicine, Cardiff, UK
J. E. Hall
Affiliation:
University of Wales College of Medicine, Department of Anaesthetics and Intensive Care Medicine, Cardiff, UK
Get access

Extract

Summary

Background and objective: The application of cricoid force is central to techniques that reduce the risk of gastric regurgitation and the subsequent pulmonary aspiration associated with obstetric and emergency anaesthesia. The discomfort associated with cricoid force in awake preoperative patients increases the incidence of coughing, struggling and pain during induction of anaesthesia. This study determined if increasing the surface area of a cricoid yoke reduced the associated discomfort in volunteers.

Methods: Fifty volunteers participated in a randomized single-blinded study. The cricoid yoke was positioned using standard anatomical landmarks and forces of 10, 20, 30 and 40 N were applied in a random order for 20 s, using two different yoke attachments with surface areas of 3 and 10 cm2. A rest of 30 s was allowed between the application of forces. Discomfort was graded by volunteers on a scale from 0 to 10 (0: no discomfort; 10: worse discomfort imaginable). A score of 10 was allocated if the volunteers could not tolerate the applied force for 20 s.

Results: Median scores for the small yoke were always higher than those for the large yoke at each force. There were significant differences between the scores for the small and large yokes at 10 and 20 N (P < 0.001) and 30 N (P = 0.0233), but there was no significant difference at 40 N.

Conclusions: The larger yoke was tolerated better by volunteers when clinically relevant cricoid forces were applied.

Type
Original Article
Copyright
© 2003 European Society of Anaesthesiology

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Sellick BA. Cricoid pressure to control regurgitation of stomach contents during induction of anaesthesia. Lancet 1961; 1: 404406.Google Scholar
Fanning GL. The efficacy of cricoid pressure in preventing regurgitation of gastric contents. Anesthesiology 1970; 32: 553555.Google Scholar
Brimacombe JR, Berry AM. Cricoid pressure. Can J Anaesth 1997; 44: 414425.Google Scholar
Rosen M. Anaesthesia for obstetrics. Anaesthesia 1981; 36: 145146.Google Scholar
Moir DD. Maternal mortality and anaesthesia. Br J Anaesth 1980; 52: 13.Google Scholar
Meek T, Gittins N, Duggan JE. Cricoid pressure knowledge and performance amongst anaesthetic assistants. Anaesthesia 1999; 54: 5961.Google Scholar
Meek T, Vincent A, Duggan JE. Cricoid pressure: can protective force be sustained? Br J Anaesth 1998; 80: 672674.Google Scholar
Howells TH, Chamney AR, Wraight WJ, Simons RS. The application of cricoid pressure. An assessment and a survey of its practice. Anaesthesia 1983; 38: 457460.Google Scholar
Lawes EG. Cricoid pressure with or without the ‘cricoid yoke’. Br J Anaesth 1986; 58: 13761379.Google Scholar
Lawes EG, Duncan PW, Bland B, Gemmel L, Downing JW. The cricoid yoke – a device for providing consistent and reproducible cricoid pressure. Br J Anaesth 1986; 58: 925931.Google Scholar
Vanner RG, O'Dwyer JP, Pryle BJ, Reynolds F. Upper oesophageal sphincter pressure and the effect of cricoid pressure. Anaesthesia 1992; 47; 95100.Google Scholar
Vanner RG, Pryle BJ. Regurgitation and oesophageal rupture with cricoid pressure: a cadaver study. Anaesthesia 1992; 47: 732735.Google Scholar
Wraight WJ, Chamney AR, Howells TH. The determination of an effective cricoid pressure. Anaesthesia 1983; 38: 461466.Google Scholar
Vanner RG. Tolerance of cricoid pressure by conscious volunteers. Int J Obstet Anaesth 1992; 1: 195198.Google Scholar
Grant LJ. Regulations and safety in medical equipment design. Anaesthesia 1998; 53: 13.Google Scholar
Vanner RG, Pryle BJ. Nasogastric tubes and cricoid pressure. Anaesthesia 1993; 48: 11121113.Google Scholar
Backhouse KM, Hutchings RT. A Colour Atlas of Surface Anatomy Clinical and Applied. London, UK: Wolfe, 1986.
Taylor TH, Major E. Hazards and Complications of Anaesthesia. Edinburgh, UK: Churchill Livingstone, 1993.