title: The effect of a cervical collar on the seal pressure of the LMA Supreme™: a prospective, crossover trial.
abstract: For personnel inexperienced in airway management, supraglottic airway devices may be the first choice in an emergency. Changing head position is known to reduce the seal pressure of a laryngeal mask airway. The aim of this study was to investigate whether the use of a cervical collar improves the stability of airways secured with the LMA Supreme™ (The Laryngeal Mask Company Limited, Mahé, Seychelles). In this crossover trial, the primary endpoint was the difference in the seal pressure of the LMA Supreme in anaesthetised patients in maximum passive extension of the neck, with and without a cervical collar. The median (IQR [range]) seal pressure was 18 (13.8-22.1 [0-30]) cmH(2) O in maximum passive extension without a cervical collar. With a cervical collar in place, the seal pressure increased to 28 (22.8-30 [17-30]) cmH(2) O (p<0.001). In the neutral head position, the seal pressure was 22 (17.6-24.5 [12-30]) cmH(2) O without and 27 (22-30 [12-30]) cmH(2) O with a cervical collar in place (p<0.001). We found that a cervical collar stabilises the airway with an LMA Supreme in place and we recommend this combination for (pre-hospital) emergency cases.
authors.affiliation: Department of Anaesthesiology, Intensive Care Medicine and Pain Management, University Hospital Giessen and Marburg GmbH, Campus Giessen, Giessen, Germany.  
authors.forename: V
authors.initials: V
authors.lastname: Mann
authors.forename: T
authors.initials: T
authors.lastname: Spitzner
authors.forename: T
authors.initials: T
authors.lastname: Schwandner
authors.forename: S T W
authors.initials: ST
authors.lastname: Mann
authors.forename: M
authors.initials: M
authors.lastname: Müller
authors.forename: J
authors.initials: J
authors.lastname: Ahlbrandt
authors.forename: M A
authors.initials: MA
authors.lastname: Weigand
authors.forename: R
authors.initials: R
authors.lastname: Röhrig
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000399:Air Pressure; D015992:Body Mass Index; D018592:Cross-Over Studies; D016267:External Fixators; D005260:Female; D006257:Head; D006801:Humans; D017214:Laryngeal Masks; D008297:Male; D008875:Middle Aged; D009333:Neck; D009765:Obesity / Q000150:complications / Q000503:physiopathology; D011229:Preanesthetic Medication; D011446:Prospective Studies; D012149:Restraint, Physical; D018401:Sample Size; D055815:Young Adult