Vladimir Nekhendzy1,2, Vijay K Ramaiah3, Jeremy Collins3, Hendrikus J Lemmens3, Sam P Most4. 1. Department of Anesthesiology, Perioperative and Pain Medicine, Stanford University School of Medicine, Stanford, CA, USA - nek@stanford.edu. 2. Department of Otolaryngology-Head and Neck Surgery, Stanford University School of Medicine, Stanford, CA, USA - nek@stanford.edu. 3. Department of Anesthesiology, Perioperative and Pain Medicine, Stanford University School of Medicine, Stanford, CA, USA. 4. Department of Otolaryngology-Head and Neck Surgery, Stanford University School of Medicine, Stanford, CA, USA.
Abstract
BACKGROUND: The use of flexible laryngeal mask airway (FLMA) in elective ear, nose and throat (ENT) surgery offers significant advantages, but is frequently considered inferior to tracheal intubation (TI) for ventilation and airway protection. We investigated the safety and success rate of intraoperative FLMA use with positive pressure ventilation (PPV), and the factors responsible for FLMA failure. METHODS: A 15-year single center retrospective study. FLMA failure was defined as the need for FLMA removal and TI, either during induction (primary failure), or after turning the patient over to the surgeon (secondary failure). Strict failure criteria included the inability to achieve and/or maintain all 3 essential FLMA functions, such as ventilation (tidal volume ≥6 mL/kg), airway protection from above the cuff (airway sealing pressure [ASP] >12 cm H2O), and separation of the respiratory and gastrointestinal tracts (absent gastric insufflation during PPV). RESULTS: In 685 patients, FLMA was successfully inserted in 94%. Secondary failure rate was 1.5%, with half of failures observed intraoperatively. The inability to seat FLMA during induction or FLMA dislodgment were the most common reasons for failures. The number of FLMA insertion attempts and low ASP were associated with FLMA primary failure and the need for TI. There were no complications. CONCLUSIONS: The results suggest an acceptably low failure rate of use of FLMA with PPV in selected ENT surgical procedures. True intraoperative FLMA failure is uncommon. We advocate observing strict criteria for adequacy of FLMA placement, and close monitoring of FLMA function intraoperatively at all times.
BACKGROUND: The use of flexible laryngeal mask airway (FLMA) in elective ear, nose and throat (ENT) surgery offers significant advantages, but is frequently considered inferior to tracheal intubation (TI) for ventilation and airway protection. We investigated the safety and success rate of intraoperative FLMA use with positive pressure ventilation (PPV), and the factors responsible for FLMA failure. METHODS: A 15-year single center retrospective study. FLMA failure was defined as the need for FLMA removal and TI, either during induction (primary failure), or after turning the patient over to the surgeon (secondary failure). Strict failure criteria included the inability to achieve and/or maintain all 3 essential FLMA functions, such as ventilation (tidal volume ≥6 mL/kg), airway protection from above the cuff (airway sealing pressure [ASP] >12 cm H2O), and separation of the respiratory and gastrointestinal tracts (absent gastric insufflation during PPV). RESULTS: In 685 patients, FLMA was successfully inserted in 94%. Secondary failure rate was 1.5%, with half of failures observed intraoperatively. The inability to seat FLMA during induction or FLMA dislodgment were the most common reasons for failures. The number of FLMA insertion attempts and low ASP were associated with FLMA primary failure and the need for TI. There were no complications. CONCLUSIONS: The results suggest an acceptably low failure rate of use of FLMA with PPV in selected ENT surgical procedures. True intraoperative FLMA failure is uncommon. We advocate observing strict criteria for adequacy of FLMA placement, and close monitoring of FLMA function intraoperatively at all times.