The Ambu AuraGain produces higher oropharyngeal leak pressure (OLP) than the LMA Supreme in patients undergoing general anaesthesia for various surgeries, according to a study presented here at the 2017 Annual Meeting of the Canadian Anesthesiologists Society (CAS).
OLP represents the airway pressure at which gas leaks back around the supraglottic airway cuff, explained Amélie Dallaire, MD, Toronto Western Hospital, Toronto, Ontario.
“We found a difference in OLP that was statistically significant,” he said.
The prospective investigation involved 105 patients who had undergone ambulatory procedures such as knee arthroscopy, correction of strabismus, and bladder surgery. Patients were randomised to receive the AuraGain (n = 51) or the Supreme (n = 54).
Morbidly obese patients were not included in the study, and patients in both arms were similar in terms of age, gender distribution, and body mass index.
OLP was significantly higher for those patients exposed to the Ambu AuraGain compared with those exposed to the LMA Supreme (25.6 cmH20 vs 21.1 cmH2O; P < .001).
Higher OLPs are particularly relevant in treating heavier patients, which would represent cases where the newer technology would have a clinical role, said Dr. Dallaire.
“The new device would be helpful in a situation where you expect higher ventilation pressure,” he said. “If the ventilation pressure exceeds the OLP, there will be a major leak around the device, and you won’t be able to ventilate your patient properly. You can expect higher ventilation pressure in more obese patients. In these clinical cases, the AuraGain could be more useful.”
Insertion time was significantly longer with the Ambu AuraGain (13.5 vs 11.4 seconds; P < .001). A total of 3 insertion attempts were allowed in the study.
“We also asked anaesthesiologists about their satisfaction with ease of insertion of the device,” said Dr. Dallaire. “When we questioned them, more said the Ambu AuraGain was more difficult to insert compared with the LMA Supreme.”