Superior Laryngeal Nerve Block for Microlaryngoscopic Surgery: A Systematic Review and Meta-Analysis

Area of Science:

• Anesthesiology and surgical safety.
• Airway management and procedural outcomes.

Background:

• Microlaryngoscopic surgery (MLS) often leads to postoperative sore throat and cough.
• Anesthetic techniques aim to improve patient comfort and surgical outcomes.

Purpose of the Study:

• To evaluate the safety and efficacy of superior laryngeal nerve block (SLNB) in patients undergoing MLS.
• To compare outcomes of SLNB versus no SLNB in randomized controlled trials.

Main Methods:

• Systematic literature search across multiple databases (PubMed, Embase, Web of Science, etc.) and trial registries.
• Inclusion of randomized controlled trials (RCTs) adhering to PICOS principles.
• Primary outcome: incidence of severe postoperative sore throat (POST); Secondary outcomes: perioperative hemodynamics (MAP, HR), postoperative cough, and anesthesia recovery time.

Main Results:

• Eleven RCTs involving 728 patients were analyzed.
• SLNB significantly reduced severe POST at multiple time points (30 min, 2h, 4-6h, 24h) and severe postoperative cough (30 min, 2h).
• SLNB demonstrated improved perioperative hemodynamic stability (lower MAP and HR) and shorter anesthesia recovery time.

Conclusions:

• Superior laryngeal nerve block is a safe and effective adjunct for microlaryngoscopic surgery.
• SLNB reduces the incidence of severe postoperative sore throat and cough.
• SLNB contributes to more stable perioperative hemodynamics and faster anesthesia recovery.