LMA-Larnygeal Mask Airway

The LMA airway is a supraglottic airway management device.

 

An LMA consists of a wide-bore tube whose proximal end connects to a breathing circuit with a standard 15-mm connector, and whose distal end is attached to an elliptical cuff that can be inflated through a pilot tube.

 

The deflated cuff is lubricated and inserted blindly into the hypopharynx so that, once inflated, the cuff forms a low-pressure seal around the entrance to the larynx.  

 

An ideally positioned cuff is bordered by the base of the tongue superiorly, the pyriform sinuses laterally, and the upper

esophageal sphincter inferiorly. If the esophagus lies within the rim of the cuff, gastric distention and regurgitation become a distinct possibility. 

 

If an LMA is not functioning properly after attempts to improve the fit have failed, most practitioners will try another LMA one size larger or smaller.

 

Down-folding of the epiglottis or distal cuff accounts for many failures. LMA insertion under direct visualization with a laryngoscope or fiberoptic bronchoscope may prove beneficial in difficult cases.

 

Partial cuff inflation prior to insertion may also be helpful.

 

The shaft of the LMA can be secured with tape.

 

The LMA partially protects the larynx from pharyngeal secretions (but not gastric regurgitation), and it should remain in place until the patient has regained airway reflexes, usually signaled by coughing and/or mouth opening on command.

 

Though not clearly a substitute for tracheal intubation, the LMA has proven helpful as a temporary measure in patients with difficult airways because of the ease of insertion and relatively high success rate.

 

It has been used as a conduit for an intubating stylet (eg, bougie), ventilating jet stylet, flexible FOB, or small-diameter (6.0-mm) tracheal tube. Several LMAs are available that have been modified to facilitate placement of a largertracheal tube with or without the use of an FOB.

 

Contraindications to the LMA:

Patients with pharyngeal pathology (eg, abscess).

 

Pharyngeal obstruction.

 

Full stomachs (eg, pregnancy, hiatal hernia).

 

Low pulmonary compliance (eg, restrictive airways disease) requiring peak inspiratory pressures greater than 30 cm H2O.

 

 

Fast Track LMA

Facilitates intubation, blind or fiberoptic.

 

Rigid, anatomically curved airway device that is wide enough to accept an 8.0 mm cuffed ETT and short enough to ensure passage of the ETT cuff beyond the vocal cords.

 

Has a rigid handle to facilitate one-handed insertion, removal, and adjustment of the device's position to enhance oxygenation and alignment with the glottis.

 

Also has an epiglottic elevating bar in the mask aperture which elevates the epiglottis as the ETT is passed through and a ramp which directs the tube centrally and anteriorly to reduce the risk of arytenoid trauma or esophageal placement.

 

Available in three sizes, one size for children, two sizes for adults.

 

I-Gel LMA

Designed to create a non-inflatable, anatomical seal of the pharyngeal, laryngeal and perilaryngeal structures while avoiding compression trauma-no inflatable cuff.

 

Gastric channel designed to improve patient safety.

 

Integral bite-block reduces the possibility of airway channel occlusion.

 

Reduces the possibility of epiglottis downfolding and obstructing the airway.