Skip to main content
    • Aa
    • Aa

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

  • A. E. Campbell (a1), A. Turley (a1), A. R. Wilkes (a1) and J. E. Hall (a1)


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.

Corresponding author
Correspondence to: Alison Campbell, Anaesthetics Department, Singleton Hospital, Swansea, SA2 8QA, UK. Tel/Fax: +44 (0)1792 285427
Linked references
Hide All

This list contains references from the content that can be linked to their source. For a full set of references and notes please see the PDF or HTML where available.

FanningGL. The efficacy of cricoid pressure in preventing regurgitation of gastric contents.Anesthesiology1970; 32: 553555.

BrimacombeJR, BerryAM. Cricoid pressure.Can J Anaesth1997; 44: 414425.

RosenM. Anaesthesia for obstetrics.Anaesthesia1981; 36: 145146.

MoirDD. Maternal mortality and anaesthesia.Br J Anaesth1980; 52: 13.

MeekT, GittinsN, DugganJE. Cricoid pressure knowledge and performance amongst anaesthetic assistants.Anaesthesia1999; 54: 5961.

MeekT, VincentA, DugganJE. Cricoid pressure: can protective force be sustained?Br J Anaesth1998; 80: 672674.

HowellsTH, ChamneyAR, WraightWJ, SimonsRS. The application of cricoid pressure. An assessment and a survey of its practice.Anaesthesia1983; 38: 457460.

LawesEG. Cricoid pressure with or without the ‘cricoid yoke’.Br J Anaesth1986; 58: 13761379.

LawesEG, DuncanPW, BlandB, GemmelL, DowningJW. The cricoid yoke – a device for providing consistent and reproducible cricoid pressure.Br J Anaesth1986; 58: 925931.

VannerRG, O'DwyerJP, PryleBJ, ReynoldsF. Upper oesophageal sphincter pressure and the effect of cricoid pressure.Anaesthesia1992; 47; 95100.

VannerRG, PryleBJ. Regurgitation and oesophageal rupture with cricoid pressure: a cadaver study.Anaesthesia1992; 47: 732735.

WraightWJ, ChamneyAR, HowellsTH. The determination of an effective cricoid pressure.Anaesthesia1983; 38: 461466.

VannerRG. Tolerance of cricoid pressure by conscious volunteers.Int J Obstet Anaesth1992; 1: 195198.

GrantLJ. Regulations and safety in medical equipment design.Anaesthesia1998; 53: 13.

VannerRG, PryleBJ. Nasogastric tubes and cricoid pressure.Anaesthesia1993; 48: 11121113.

Recommend this journal

Email your librarian or administrator to recommend adding this journal to your organisation's collection.

European Journal of Anaesthesiology
  • ISSN: 0265-0215
  • EISSN: 1365-2346
  • URL: /core/journals/european-journal-of-anaesthesiology
Please enter your name
Please enter a valid email address
Who would you like to send this to? *



Abstract views

Total abstract views: 46 *
Loading metrics...

* Views captured on Cambridge Core between September 2016 - 22nd September 2017. This data will be updated every 24 hours.