Lost cap of ProSeal™ LMA vent has some substitutes

Abstract

Sir,

The ProSeal™ Laryngeal Mask Airway (PLMA) is a commonly used device to manage difficult airway in anesthesia practice. Structurally, it consists of four components; mask with a cuff. An airway tube, a draining tube and an inflation line terminating in the pilot balloon with attached valve for mask inflation as well as deflation. A red plug or manual vent is also fitted to the valve assembly which allows for the residual air in the mask to be vented. Thus keeping it open prevents the expansion of the cuff especially during steam autoclaving. Recently, while undertaking the routine checkup of the instruments in the OR, we discovered that the cap of the manual vent of a PLMA (size 3) was missing, making cuff inflation impossible. We explored the available options to make it useful again, including the rubber cap of the port of HME filter (INTERSURGICAL) (Figure 1). Consequently proper air seal could be created and the cuff could be inflated effectively again. The repaired PLMA performed satisfactorily providing adequate seal and without any loss of airway pressures in patients. Previous reports have described replacement of various parts of PLMA including damaged inflation line and the damaged valve with the PVC inflation line and functional valve from various sources respectively.^1,2 The replacement of non-functioning inflation valves with functional valves of discarded classic LMA and PLMA has also been reported previously .³

Additionally, stoppers of IV cannula, stoppers of triway or a 2 ml syringe can also be used in place of manual vent cap to create proper airway seal (Figure 1). However, the adequate functioning of the other parts must be ensured prior to using these devices in clinical practice.