Laryngeal mask airways – to inflate or to deflate after insertion?

Abstract

This study demonstrates that LMAs, particularly when using small-sized LMAs or LMAs with a more rigid PVC surface, need to be deflated following insertion of the device rather than inflated to avoid cuff hyperinflation. Hence, cuff pressures should be measured routinely using a manometer to minimize potential pressure-related airway complications.

The laryngeal mask in infants and children: What is the cuff pressure?

“…Our finding of higher cuff pressures in larger LMAs is somewhat surprising given previous studies to the contrary [13,14]. Von Ungern-Sternberg et al conducted a similar study in which they found intracuff pressures to be significantly higher in size 1 LMAs when compared to all other sizes [13]. Similarly, Wallace et al plotted pressure volume curves for pediatric LMAs and described a particularly steep curve for size 1 LMAs [14].…”

“…The results of this quality assurance study indicate a significant number of hyperinflated LMAs in our pediatric population, especially in larger sized LMAs. Our finding of higher cuff pressures in larger LMAs is somewhat surprising given previous studies to the contrary [13,14]. Von Ungern-Sternberg et al conducted a similar study in which they found intracuff pressures to be significantly higher in size 1 LMAs when compared to all other sizes [13].…”

A randomised comparison of the self‐pressurised air‐QTM intubating laryngeal airway with the LMA UniqueTM in children*

“…Outcomes measured were airway leak pressure, ease and time for insertion, fibreoptic examination, incidence of gastric insufflation and complications. Median (IQR [range]) time to successful device placement was faster with the air-Q SP (12 (10-15 [5][6][7][8][9][10][11][12][13][14][15][16][17][18])) s than with the LMA-Unique (14 (12-17 [6][7][8][9][10][11][12][13][14][15][16][17][18][19][20][21][22]) s; p = 0.05). There were no statistically significant differences between the air-Q SP and LMA-Unique in initial airway leak pressures (16 (14-18 [10- …”

“…An increase in airway leak pressure of both devices at 10 min may indicate some degree of moulding of the device in the posterior pharynx improving airway seal. Adjustments of the intracuff pressure are sometimes needed to maintain an adequate airway seal and prevent overinflation of the cuff when using supraglottic airways [20][21][22]. In this respect, the use of the air-Q SP may represent a benefit, as it may be more convenient than supraglottic airways with inflatable cuffs.…”

Baby cuff as a reason for laryngeal mask airway cuff malfunction during airway management for anesthesia

“…Hence, cuff pressures should be measured routinely using a manometer to minimize potential pressure-related airway complications. [7] Joshi et al . showed that the ability to generate airway pressure of 20 cmH2O and ability to ventilate manually is a good test compared to fiberoptic bronchoscopy.…”