To compare the efficacy and safety of traditional inflatable laryngeal mask, i-gel non-inflatable laryngeal mask and GMA-TULIP non-inflatable laryngeal mask in surgeries with lateral position under general anesthesia, so that providing evidence for the selection of laryngeal mask in surgeries with lateral position.

Laryngeal mask and tracheal intubation are the two most commonly used airway management methods for patients under general anesthesia. Compared with tracheal intubation, laryngeal mask is only placed in the throat without the need for laryngoscope to expose the glottis, not entering the glottis and trachea, so it will not cause mechanical damage to the vocal cords and trachea. Moreover, the insertion of laryngeal mask reduces the excitation of sympathetic and vagus nerves, has a relatively mild effect on physiological status, and significantly reduces cardiovascular reactions, which is convenient for maintaining hemodynamic stability during anesthesia induction and patients can tolerate the tube better without coughing or agitation during recovery from the anesthesia. Therefore, laryngeal masks are currently widely used in airway management during general anesthesia. Studies have shown that about 3 million patients in the UK National Health Service system receive anesthesia surgery with different types of airway management every year, and the use of laryngeal masks is higher than that of tracheal intubation, accounting for about 56.2%.

Since its introduction, many new laryngeal masks have been improved and applied to clinical practice based on the classic laryngeal mask. A key indicator for evaluating the performance of laryngeal masks is their sealing effect on the airway. Currently, laryngeal masks are mainly divided into two categories: inflatable laryngeal masks and non-inflatable laryngeal masks. Inflatable laryngeal masks are traditional types, including BlockBuster, Superme, ProSeal, and Fastrach, which are the most widely used in clinical practice. Non-inflatable laryngeal masks are designed with a mirror image of the throat opening and use thermoplastic elastomer materials to achieve a gas tightness effect similar to that of inflatable laryngeal masks. The i-gel laryngeal mask is currently the most commonly used non-inflatable type. A meta-analysis found that the sealing pressure of the i-gel laryngeal mask is higher than that of traditional inflatable laryngeal masks, indicating better airway sealing performance for non-inflatable laryngeal masks. The GMA-TULIP non-inflatable laryngeal mask is a new type of non-inflatable laryngeal mask with advantages such as a C-shaped double gastric tube channel, a stable platform for the tongue base, a soft tissue sealing ring, a prominent epiglottis attachment, and a design that matches the anatomical structure of the throat opening. Compared with inflatable laryngeal masks, the GMA-TULIP mask is more in line with anatomical positioning design, theoretically providing higher sealing effect on the airway.

Although the laryngeal mask has been successfully applied to the airway management of surgeries with lateral position under general anesthesia, its widespread use is limited due to the special position of lateral position, which may lead to laryngeal mask displacement, poor airway tightness, and air leakage. Therefore, exploring a laryngeal mask with better airway sealing effect in surgeries with lateral position under general anesthesia will help promote the clinical application of laryngeal mask, reduce airway injury and hemodynamic fluctuation, and improve patient comfort. To this end, this project plans to compare the application effects of traditional inflatable BlockBuster laryngeal mask, i-gel non-inflatable laryngeal mask, and GMA-TULIP non-inflatable laryngeal mask in surgeries with lateral position under general anesthesia, providing clinical evidence for the selection of laryngeal mask in surgeries with lateral position under general anesthesia.

Inclusion Criteria:

1. Patients received surgeries in lateral position with an estimated surgery duration of less than 3 hours under general anesthesia.
2. Ages between 18 to 80, and body mass index less than 28 kg/m².
3. American Society of Anesthesiologists (ASA) Grades I-III.
4. Patients are willing to participate and be able to understand and sign an informed consent form.

Exclusion Criteria:

1. Individuals with an open bite of less than 2cm.
2. Individuals with a history of obvious regurgitation of gastric contents and risk factors for aspiration.
3. Patients with combined pharyngeal and laryngeal lesions.
4. Predicting difficult airway patients.
5. Hearing, intellectual, communication, and cognitive impairments.
6. Any reason that prevents cooperation with the study or that the researcher deems inappropriate for inclusion in this trial.

Individual participant data (IPD) will be available with the responding author when required.

The data will become available when publish and keep it for 5 years.

Researchers who provide a methodologically sound proposal.