Functions and structural features of silicone laryngeal masks

The three basic airway management devices are face masks, laryngeal masks, and endotracheal tubes. Silicone laryngeal masks are the mainstream high-end category of supraglottic airway devices (SADs). As one of the three core tools of modern airway management, the silicone laryngeal mask fills the gap between face masks and endotracheal tubes, serving as a first-line alternative for difficult airway emergencies and a key device for balancing infection control and cost. It belongs to the supraglottic airway ventilation category, used to establish a temporary artificial airway during general anesthesia and emergency situations. It does not enter the trachea but only conforms to the pharyngeal cavity.

1. Intraoperative ventilation and oxygen supply: Connects to anesthesia machine/ventilator to deliver oxygen and anesthetic gas, enabling spontaneous breathing or mechanical positive pressure ventilation. Suitable for short to medium-duration surgeries.

2. Emergency Airway Management: Rapid airway establishment for respiratory arrest, difficult intubation, sedation resuscitation, painless gastroscopy/colonoscopy/outpatient procedures, which is simpler and less invasive than endotracheal intubation.

3. Reduced airway damage: It does not require passing through the glottis and does not irritate the trachea. Compared with endotracheal intubation, the incidence of coughing, laryngospasm, vocal cord damage, and postoperative sore throat is significantly reduced.

4. Assisted Airway Maneuvers: A fiberoptic bronchoscope and suction catheter can be inserted through the laryngeal mask airway, facilitating airway examination and secretion suction.

5. Partial Prevention of Gastric Reflux: After the mask airway is inflated, it closes the oropharyngeal cavity, preventing the reflux of gastric contents to some extent. However, it cannot completely prevent aspiration. Use with caution in patients with a full stomach or at high risk of reflux.

1. Ventilation Tube: A hollow medical-grade silicone tube serving as the air inlet and outlet channel; available in standard straight tube and reinforced steel wire versions to prevent bending; sizes 1-5 are available to fit newborns and adults.

2. Distal Cuff (Ventilation Mask/Bag): A flexible silicone bag that inflates after insertion into the pharynx, conforming to the base of the tongue and around the epiglottis to seal the oropharynx and create an airway; the soft silicone reduces pressure on the mucous membranes.

3. Inflation Tube: A thin silicone tube attached to the outside of the ventilation tube, connecting the cuff to the indicator cuff, used for inflating and deflating the cuff.

4. Indicator Cuff (Pressure Monitoring Cuff): A small cuff at the end of the inflation tube, allowing for a rough assessment of the cuff's inflation pressure by touch; it can be connected to a pressure monitoring gauge for precise control of the cuff's internal pressure, preventing ischemia due to pressure on the pharyngeal mucosa.

5. Standard 15mm Universal Connector: The proximal interface of the catheter, conforming to national standard specifications, compatible with anesthesia circuits, ventilators, and simple breathing bags.

6. Gastric Drainage Channel: The dual-lumen silicone laryngeal mask airway features a unique design with one ventilation channel and one independent gastric tube channel. This allows for the insertion of a gastric tube to drain gastric fluid, significantly reducing the risk of reflux and aspiration. Commonly used in laparoscopic procedures and for obese patients.

7. Anti-slip Protrusions/Shaping Structure on the Back: The mask airway features a shaping design on the back that conforms to the anatomy of the human throat, reducing displacement and air leakage.