A laryngeal mask airway(LMA) was first described by Brain1) in 1983. It has been used worldwide as a preferable airway for outpatient anesthesia as well as an emergency airway to overcome the difficult airway. It can be inserted into the
hypopharyngeal
area in a blind technique. However, because the tongue is displaced against the posterior pharyngeal wall in a sedated and/or relaxed patients, we occasionally encounter a difficulty in inserting LMA in a blind technique even with jaw thrust
maneuver2,3), rotational movement4) of LMA. With a forceful insertion against resistance, the LMA tip may damage to the uvula4). So a laryngoscopic aid4,5) may be helpful to facilitate a LMA insertion. However, it is well known that a
laryngoscope
may
damage to the the upper teeth or lip.
I devised an introducer to facilitate to a LMA placement. The "L"-shaped introducer is made of the stainlesssteel tablespoon which is easily got from a kitchen. It is made by appropriately bending the shaft of the tablespoon, and it has several
holes on
the distal oval plate of the spoon to drain secretions(Fig. 1) It can ease a LMA insertion by lifting the posteriorly displaced tongue base form the posterior wall and the soft palate(Fig. 2).
I compared changes in arterial blood pressure of LMA(Intravent, Pacific Medical, Supplies Pty Lte., Melbourne Australia) insertion with this device to those of the blind insertion technique in 36 female patients (introducer group, n=20; blind
technique
group, n=16). I observed that there was a significant increase of mean arterial blood pressure 1 minute after LMA placement compared with the immediate placement values in both groups.(P<0.01 by student's t-test). However, there were no
statistically
significant differences of one-minut mean-arterial blood pressure between the two groups. Thus I concluded that a LMA placement with the introducer had comparable hemodynamic changes to the blind insertion technique.
I think the introducer it has several advantages: easy to get and make, easy to learn how to use, smaller and less heavier than a laryngoscope(easy to handle), no damages to the upper teeth or lip, making more room.
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