Blind intubation of anaesthetised children with supraglottic airway devices AmbuAura-i and Air-Q cannot be recommended A randomised controlled trial

BACKGROUNDPaediatric supraglottic airway devices AmbuAura-i and Air-Q were designed as conduits for tracheal intubation. Although fibreoptic-guided intubation has proved successful, blind intubation as a rescue technique has never been evaluated.OBJECTIVEEvaluation of blind intubation through AmbuAura-i and Air-Q. On the basis of fibreoptic view data, we hypothesised that the success rate with the AmbuAura-i would be higher than with the Air-Q.DESIGNA randomised controlled trial.SETTINGUniversity Childrens' Hospital; September 2012 to July 2014.PATIENTSEighty children, American Society of Anesthesiologists (ASA) class I to III, weight 5 to 50kg.INTERVENTIONSTracheal intubation was performed through the randomised device with the tip of a fibrescope placed inside and proximal to the tip of the tracheal tube. This permitted sight of tube advancement, but without fibreoptic guidance (visualised blind intubation).MAIN OUTCOME MEASURESPrimary outcome was successfully visualised blind intubation; secondary outcomes included supraglottic airway device success, insertion times, airway leak pressure, fibreoptic view and adverse events.RESULTSPersonal data did not differ between groups. In contrast to our hypothesis, blind intubation was possible in 15% with the Air-Q and in 3% with the AmbuAura-i [95% confidence interval (95% CI) 6 to 31 vs. 0 to 13%; P=0.057]. First attempt supraglottic airway device insertion success rates were 95% (Air-Q) and 100% (AmbuAura-i; 95% CI 83 to 99 vs. 91 to 100; P=0.49). Median leak pressures were 18cmH(2)O (Air-Q) and 17cmH(2)O [AmbuAura-i; interquartile range (IQR) 14 to 18 vs. 14 to 19cmH(2)O; P=0.66]. Air-Q insertion was slower (27 vs. 19s, P<0.001). There was no difference in fibreoptic view, or adverse events (P>0.05). In one child (Air-Q size 1.5, tube size 3.5), the tube dislocated during device removal.CONCLUSIONVentilation with both devices is reliable, but success of blind intubation is unacceptably low and cannot be recommended for elective or rescue purposes. If intubation through a paediatric supraglottic airway device is desired, we suggest that fibreoptic guidance is used.TRIAL REGISTRATIONClinicaltrials.gov identifier: NCT01692522.