Author: Ethan Covey
A single-use flexible laryngeal mask proved to be a safe alternative airway device for use in pediatric adenotonsillectomy, and it appears to reduce OR time, according to a new study.
“Flexible—or armored—supraglottic airway devices have been successfully used in patients undergoing adenotonsillectomies for many years in other countries,” said Amy Graham-Carlson, MD, an assistant professor of pediatric anesthesiology at McGovern Medical School at University of Texas Health, in Houston. “For one reason or another, we have been slow or unwilling to adopt this practice in pediatric anesthesia here in the U.S.”
Dr. Graham-Carlson and her colleagues explored whether these airways conferred a benefit by reducing intraoperative or postoperative airway events, whether they reduced the amount of time the patient is in the OR, and whether any barriers to use existed for pediatric patients. The results were presented at the 2019 annual meeting of the Society for Pediatric Anesthesiology/American Association of Pediatrics, held earlier this year.
The researchers conducted a retrospective review of patients aged 2 to 17 years who underwent an adenotonsillectomy over a 12-month period. A total of 289 patients were included in the study: 94 who received the LMA Flexible (Teleflex) and 195 who received an oral right-angle endotracheal tube (RA ETT).
Dr. Graham-Carlson and her team found that the LMA Flexible was a safe, effective alternative to an oral RA ETT. Only 4% of patients required conversion from the flexible airway to the RA ETT device (Table).
|Table. Demographics and OR Time Results RA ETT, right-angle endotracheal tube|
|Characteristics||LMA Flexible||Oral RA ETT|
|Number of patients||94 (98–4 converted)||195 (191+4 converted)|
|Ages, years (range)||7.1 (2-17)||6.2 (2-17)|
|Weight, kg (range)||30.3 (12.1-106.8)||28.8 (10.5-120.5)|
|OR time, minutes (range)||14.4 (3-40)||19.0 (2-41)|
Additionally, the average time from end of surgery to wheels out was shorter with the LMA Flexible: 14.4 minutes compared with 19 minutes when using the RA ETT.
However, the team noted that proper placement of the LMA Flexible, and its relationship with the McIvor mouth gag with tongue retractor, could be difficult. “We found that it is feasible to use a flexible LMA in our patients undergoing adenotonsillectomies if an experienced ENT [ear, nose and throat] surgeon was performing the procedure,” Dr. Graham-Carlson said. “The important nuance is that the LMA has to be pulled back and/or adjusted by the surgeon after the McIvor retractor is placed, as the retractor tends to push the LMA deeper. Junior-level ENT residents have a hard time balancing this adjustment and maintaining adequate exposure.”
Because of this, the study authors stressed the importance of cooperation between the anesthesiologist and ENT surgeon during placement of the devices.
The team also recommended use of the smallest available LMA Flexible mask size in order to prevent obstruction of the otolaryngologist’s view and provide the best fit for younger patients. The authors added, however, that the available sizes might limit use on patients less than 4 years of age.
According to Dr. Graham-Carlson, the study showed that the LMA Flexible is a promising product for these procedures, when correctly placed, and would benefit from further study. “There was a trend to greater efficiency and a trend towards fewer adverse airway events,” she said. “This was a single-center, retrospective, quality improvement project that would certainly need to be conducted in a randomized controlled trial with other institutions to make any solid conclusions from the data.”