A comparison of three types of tracheal tube for use in laryngeal mask assisted blind orotracheal intubation

Abstract

Laryngeal mask assisted blind orotracheal intubation is a technique that is best mastered under controlled circumstances. The influence of the type of tracheal tube, and positioning of the head, on the success rate of this procedure was evaluated in 90 gynaecological patients presenting for elective procedures under general anaesthesia. After induction, a laryngeal mask was introduced and its position was confirmed. Up to three attempts at blind orotracheal intubation using one of three tracheal tubes (Argyle, Portex or Kendall Curity) passed through the laryngeal mask were permitted in each patient. The success rates after a single attempt at blind oral intubation were 3.3%, 70.0% and 30.0% respectively ( p < 0.001 and p < 0.05 when Portex was compared to Argyle and Kendall Curity types). After a maximum of three attempts, success rates were 30.0% (Argyle), 93.3% ( Portex) and 76.7% (Kendall Curity). The first attempt at tracheal intubation was performed in the 'snifing the morning air position' and this was successful in 52% of successful intubations; the second attempt using extension at the atlanto-occipital joint was successful in a further 35% of successful intubations; the third attempt used varying degrees of neck JIexion and extension at the atlanto-occipital joint and this permitted successful placement of the tracheal tube in the remaining 13% of patients in whom tracheal intubation was possible.

Difficult Airway Society guidelines for management of the unanticipated difficult intubation

“…Classic LMA TM for secondary tracheal intubation: Fibreoptic tracheal intubation through the classic LMA TM (the role of the single-use LMA TM in management of the difficult airway patient has not been established) should be considered when an ILMA TM is not available. Although Heath [120] reported a 93% success rate for blind intubation through the LMA TM (in the absence of cricoid pressure), others have achieved much lower success rates [121,122] and blind intubation cannot be recommended. Success rates of 90-100% (depending on technique, equipment, number of attempts allowed and experience of user) can be achieved with fibreoptic intubation through the classic LMA TM [113,123,124].…”

The LMA Classic™ as a conduit for tracheal intubation in adult patients: a review and practical guide

“…29 Differences in technique, patient positioning and type of tracheal tube employed have resulted in significantly differing reported success rates. Single-attempt (74%, 37/50) and overall (90%, 45/50) success rates were reported in an adult population of paralysed elective surgical patients with a technique that included good lubrication and a 90 degree to the left rotation to bring the bevel anteriorly during passage of a 6-mm internal-diameter tracheal tube ( 31 achieved a single-attempt blind intubation success rate of 3.3%, 70% and 30%. After a maximum of three attempts, success rates increased to 30%, 93.3% and 76.7%, respectively.…”

The roles of the laryngeal mask airway in emergency medicine

“…Alternatively, simple blind passage of an ETT through the LMA has also been described as successful and less time consuming 42 . A recent study claimed the success rate of the simple blind ETT through LMA technique was between 30% and 93.3% depending on the brand of endotracheal tube utilised 63 .…”