Cricoid pressure – friend or foe?

Cricoid pressure was described by Sellick [1] over 40 years ago to reduce the probability of the aspiration of gastric contents onto the pulmonary tree. It subsequently became part of the technique termed rapid sequence intubation and is used in most countries of the world as an integral part of the emergency induction of anaesthesia. Its introduction into clinical practice followed a simple technique description and case series. The technique was never evaluated in a trial. Subsequently evidence has emerged to suggest that the use of CP may impair laryngoscopy and bag mask ventilation [2]. Releasing CP has been recommended as a way of improving the laryngeal view at difficult intubations. However there is limited data concerning the effects of releasing CP (with/without laryngeal manipulation) on the resultant quality of the laryngeal view and subsequent intubation's success rates [2]. We prospectively evaluated the use of CP and its release on 402 emergency pre-hospital trauma airways over 16 months. CP was released in 47 cases. Its release was associated with an improved or neutral effect on laryngeal view in all cases. Removing CP facilitated intubation in most cases and was not associated with a worsening view of the cords in any patient. There were two cases of regurgitation associated with failed intubation, prolonged BMV and the removal of CP.

CP has entered into clinical practise with scant evidence that it reduces aspiration and little evaluation of its risks and benefits. We suggest that in cases of poor laryngeal view early removal of CP is likely to facilitate intubation with little evidence of risk to the patient.