THE EFFECT OF CRICOID PRESSURE AND NECK SUPPORT ON THE VIEW AT LARYNGOSCOPY

Fifty female patients were studied to compare the view of the larynx a t direct laryngoscopy under general anaesthesia with and without crico id pressure applied. We also compared the view using the standard tech nique of cricoid pressure with that using cricoid pressure in an upwar d and backward direction and further investigated whether these views were improved with a firm foam rubber neck support. The order in which the types of cricoid pressure were applied nas randomised and also bl inded with a drape over the neck. Cricoid pressure was simulated on we ighing scales after each case and a mean force of 3.2 kg was applied. The majority of views at laryngoscopy (95%) were grade 1, with too few grade 2 and 3 views for statistical comparison. Both types of cricoid pressure applied without neck support were more likely to give a bett er view than no cricoid pressure (p < 0.01) and cricoid pressure in an upward and backward direction was more likely to give a better view a t laryngoscopy than the standard technique (p < 0.01). Neck support du ring the standard technique of cricoid pressure did not improve the vi ew of the larynx at laryngoscopy. Cricoid pressure is likely to improv e the view at laryngoscopy which may be further improved by applying i t in an upward and backward direction.