Comparison of Pentax Airway Scope and Macintosh laryngoscope for orotracheal intubation in children: A randomised non-inferiority trial.

BACKGROUND: Pentax Airway Scope (AWS) is a recently developed videolaryngoscope for use in both normal and difficult airways, yet its use in paediatric patients has not been established. The purpose of this study was to evaluate the efficacy of the Pentax AWS regarding intubation time, laryngeal view and ease of intubation in paediatric patients with normal airway, compared to Macintosh laryngoscope. METHOD: A total of 136 paediatric patients aged 1-10 with American Society of Anaesthesiologists physical status I or II undergoing general anaesthesia were randomly allocated into two groups: Macintosh laryngoscope (n = 68) and Pentax Airway Scope (n = 68). Primary outcome was intubation time. Cormack-Lehane laryngeal view grade, application of optimal laryngeal external manipulation, intubation difficulty scale, intubation failure rate and adverse events were also measured. RESULT: No significant difference was observed between the two groups regarding intubation time (P = 0.713). As for the laryngeal view grade, the Pentax group resulted in lower graded cases compared to the Macintosh group (P = 0.000). No optimal laryngeal external manipulation application was required in the Pentax group. Intubation difficulty scale resulted in lower values for Pentax group (P = 0.001). Failure rate was not different between the two groups (P = 0.619). There were significantly more teeth injury cases in the Pentax group than Macintosh group (P = 0.042). CONCLUSION: Pentax Airway Scope provided similar intubation time and success rate, while improving laryngeal view, compared to Macintosh laryngoscopy in children with normal airway. When using Pentax AWS in children, however, the risk of teeth injury may increase.

Effect of High-Flow Nasal Oxygenation on Gastric Insufflation in Patients Undergoing Laryngeal Microsurgery under Tubeless General Anesthesia with Neuromuscular Blockade.

BACKGROUND: High-flow nasal oxygenation is an oxygen delivery method by which high concentrations of heated humidified oxygen are supplied via the nasal cavity. This study aimed to investigate the effect of high-flow nasal oxygenation on gastric volume change in adult patients undergoing laryngeal microsurgery under tubeless general anesthesia with neuromuscular blockade. METHODS: Patients aged 19-80 years with an American Society of Anesthesiologists physical status 1 or 2 who were scheduled to undergo laryngoscopic surgery under general anesthesia were recruited. Patients received high-flow nasal oxygenation therapy at 70 L/min during surgery under general anesthesia with neuromuscular blockade. The cross-sectional area of the gastric antrum was measured via ultrasound in the right lateral position before and after high-flow nasal oxygenation, and the gastric volume was calculated. The duration of apnea, i.e., the duration of administration of high-flow nasal oxygenation in the paralyzed state, was also recorded. RESULTS: Of the 45 patients enrolled, 44 completed the study. There were no significant differences in the antral cross-sectional area in the right lateral position, gastric volume, and gastric volume per kg between before and after high-flow nasal oxygenation application. The median duration of apnea was 15 (interquartile range, 14-22) min. CONCLUSION: High-flow nasal oxygenation at 70 L/min during apnea with the mouth open did not influence the gastric volume in patients undergoing laryngeal microsurgery under tubeless general anesthesia with neuromuscular blockade.

Comparison of learning direct laryngoscopy using a McGrath videolaryngoscope as a direct versus indirect laryngoscope: a randomized controlled trial.

OBJECTIVE: Tracheal intubation using a direct laryngoscope is difficult to teach. The McGrath videolaryngoscope, a Macintosh-like device with a camera, can be used as a direct laryngoscope to educate novices under supervision using the screen. We compared the effect on Macintosh laryngoscopy skills following training with a McGrath videolaryngoscope as a direct versus indirect laryngoscope. METHODS: Thirty-seven participants were randomized into direct and indirect groups according to the training method using a McGrath videolaryngoscope. Participants attempted Macintosh direct laryngoscopy in normal and difficult airway scenarios. The primary endpoint was the intubation time, and the rate of successful intubation, dental trauma, and difficulty were secondary outcomes. RESULTS: The intubation time after education decreased significantly in both groups and was significantly shorter in the direct group than in the indirect group across time. The difficulty degree in the direct group was lower than that in the indirect group across time; however, the rate of dental trauma was not significantly different. CONCLUSION: Both direct and indirect laryngoscopy using a McGrath videolaryngoscope improved the performance of Macintosh direct laryngoscopy in novices, while direct laryngoscopy using a McGrath videolaryngoscope demonstrated better educational effects than indirect laryngoscopy.Registered at ClinicalTrials.gov (NCT03471975).

Comparison of McGrath, Pentax, and Macintosh laryngoscope in normal and cervical immobilized manikin by novices: a randomized crossover trial.

BACKGROUND: The aim of this study was to compare tracheal intubation performance regarding the time to intubation, glottic view, difficulty, and dental click, by novices using McGrath videolaryngoscope (VL), Pentax Airway Scope (AWS) and Macintosh laryngoscope in normal and cervical immobilized manikin models. METHODS: Thirty-five anesthesia nurses without previous intubation experience were recruited. Participants performed endotracheal intubation in a manikin model at two simulated neck positions (normal and fixed neck via cervical immobilization), using three different devices three times each. Performance parameters included intubation time, success rate of intubation, Cormack Lehane laryngoscope grading, dental click, and subjective difficulty score. RESULTS: Intubation time and success rate during first attempt were not significantly different between the 3 groups in normal airway manikin. In the cervical immobilized manikin, the intubation time was shorter (p = 0.012), and the success rate with the first attempt was significantly higher (p < 0.001) when using McGrath VL and Pentax AWS compared with Macintosh laryngoscope. Both VLs showed less difficulty score (p < 0.001) and more Cormack Lehane grade I (p < 0.001) in both scenarios. The incidence of dental clicks was higher with Macintosh laryngoscope compared with McGrath VL in cervical immobilized airway (p < 0.001). CONCLUSIONS: McGrath VL and Pentax AWS did not show clinically significant decrease in intubation time, however, they achieved higher first attempt success rate, easier intubation and better glottis view compared with Macintosh laryngoscope by novices in a cervical immobilized manikin model. McGrath VL may reduce the risk of dental injury compared with Macintosh laryngoscope in cervical immobilized scenario. TRIAL REGISTRATION: ClinicalTrials.gov (NCT03161730), May 22, 2017 https://clinicaltrials.gov/ct2/hom.