Final answer:
The primary difference among the SGAs mentioned is the Combitube and Rusch EasyTube having a double-lumen design for both ventilation and gastric access, while the Cobra Perilaryngeal airway and Tulip Airway do not have this feature.
Step-by-step explanation:
The primary difference of the mentioned double-lumen supraglottic airways (SGAs) relates to their design and intended usage. The Combitube is a double-lumen tube with one lumen opening above the larynx and the other extending into the oesophagus. The Rusch EasyTube, similar to the Combitube, also features two lumens but with distinct functionalities—one for ventilation and another for gastric access. The Cobra Perilaryngeal airway and the Tulip Airway, while also SGAs, do not have this double-lumen design.
Intubation through these devices allows air to bypass obstructions in the respiratory system. During the procedure, a tube is inserted through the nasal cavity and pharynx, passing through the larynx to reach the trachea, ensuring that air can reach the lungs effectively, with exhaled air and blood traveling from the heart being routed properly.