Efficacy of stylet angulation at the holding position during tracheal intubation with a videolaryngoscope: a randomized controlled trial

A comparison of McGrath MAC, AIRWAY SCOPE®, and AceScope® video laryngoscopes in novice healthcare providers: a randomized crossover simulation study

BACKGROUND

Video laryngoscopes are widely used for tracheal intubation, particularly in challenging airway scenarios. The McGrath MAC, AIRWAY SCOPE®, and AceScope® are popular video laryngoscopes with different design features. This study aimed to compare the effectiveness and usability of these three devices in novice healthcare providers during simulated tracheal intubation scenarios employing a manikin.

METHODS

Sixty novice healthcare providers, including nurses and pharmacists, were enrolled in this randomized crossover study. Participants performed tracheal intubation using the McGrath MAC, AIRWAY SCOPE, and AceScope in both normal airway and cervical spine immobilization models. Primary outcomes were intubation success rate and time to intubation. Secondary outcomes included user preferences, device ease of use, and the incidence of dental injuries.

RESULTS

The AIRWAY SCOPE demonstrated the shortest intubation time in both normal airway and cervical spine immobilization models (14.90 ± 1.76 s and 23.80 ± 2.43 s, respectively), followed by the McGrath MAC and AceScope. All devices exhibited high success rates, and there were no significant differences in perceived difficulty among the three video laryngoscopes. The incidence of dental injuries was generally comparable among the devices. However, in the cervical spine immobilization model, the AceScope demonstrated a significantly higher rate of dental injuries compared to the McGrath MAC (p < 0.05), highlighting a potential concern for clinical practice.

CONCLUSIONS

The AIRWAY SCOPE was the most efficient video laryngoscope in terms of intubation time, followed by the McGrath MAC and AceScope. However, all devices showed high success rates and no significant differences in perceived difficulty. Further research is needed to validate these findings in clinical settings and investigate the impact of device-specific features on intubation outcomes and dental injury incidence.

TRIAL REGISTRATION

Registration number: jRCT1030240598 ( https://jrct.niph.go.jp/re/reports/detail/91422 ) The registration date of the clinical trial is January 8, 2025.UMIN000050394.

Appropriate shape of a stylet for tracheal intubation using the McGrath® MAC videolaryngoscope in neonates: a randomized crossover simulation study

BACKGROUND

Guidelines on airway management in neonates and infants recommend using a stylet when a videolaryngoscope is used, but it is not clear if the use of a stylet facilitates tracheal intubation and which shape of the stylet is suitable in neonates.

METHODS

As a preliminary simulation study of a randomized controlled cross-over design, 25 anesthesiologists (3 specialists, 11 senior residents, and 11 junior residents) used a McGrath® MAC videolaryngoscope (Covidien, Medtronic, Tokyo, Japan) blade 1 for tracheal intubation (of a 3.5-mm ID Shiley™ tube with a cuff), with one of four differently shaped stylets (C-shaped, J-shaped, hockey stick-shaped and double C-shaped) or without a stylet in a manikin of a neonate, and compared intubation times.

RESULTS

Compared with intubation time without the use of a stylet, intubation time was significantly longer with the use of the J-shaped stylet (P = 0.007; median (95% CI) difference: 2 (1 to 2) s) or with the hockey stick-shaped stylet (P = 0.0002; median (95% CI) difference: 9 (9 to 10) s). In contrast, intubation time was similar between no stylet and the C-shaped stylet (P = 0.90; median (95% CI) difference: 0 (0 to 0) s) or between no stylet and the double C-shaped style (P = 0.60; median (95% CI) difference: 0 (0 to 0) s).

CONCLUSIONS

In conclusion, while time to tracheal intubation would be similar with and without the use of a stylet, the shape of the stylet would affect intubation time in neonates.

Safety and effectiveness of endotracheal intubation in critically ill emergency patients with videolaryngoscopy

To investigate the safety and efficacy of video laryngoscopy for endotracheal intubation in critically ill patients. A total of 106 critically ill emergency patients treated at our hospital between January 2021 and June 2022 were randomly divided into 2 groups, the visual and direct groups, with 53 patients in each group. Both groups were treated with endotracheal intubation; the visual group was treated with video laryngoscopy, and the direct group was treated with conventional direct laryngoscopy. The Cormack-Lehane grade, percentage of glottic opening score, success rate of one intubation, intubation time, number of intubation attempts, hemodynamic values, and complications were compared between the 2 groups. The success rates of glottis exposure and one-time intubation were significantly higher while the intubation time and number of intubation attempts significantly lower in the visual group than in the direct group. The heart rate, mean arterial pressure (MAP), or blood oxygen saturation did not differ significantly between the 2 groups 10 minutes after entering the room (T0) or after anesthesia induction (T1). MAP was significantly lower in the visual group than in the direct group during immediate intubation (T2). The heart rate and MAP were significantly lower in the visual group than in the direct group 1 minute (T3) and 5 minutes (T4) after intubation. The incidences of intubation-related complications in the visual and direct groups were 7.55% and 22.60%, showing a significant difference. Endotracheal intubation under videolaryngoscopy is safer and more effective for critically ill emergency patients than conventional direct laryngoscopy. This can improve the success rate of intubation, reduce the intubation time, and reduce its effect on hemodynamics. Therefore, it is worthy of further clinical application.

Impact of Macintosh blade size on endotracheal intubation success in intensive care units: a retrospective multicenter observational MacSize-ICU study

Purpose

To investigate the impact of Macintosh blade size used during direct laryngoscopy (DL) on first-attempt intubation success of orotracheal intubation in French intensive care units (ICUs). We hypothesized that success rate would be higher with Macintosh blade size No3 than with No4.

Methods

Multicenter retrospective observational study based on data from prospective trials conducted in 48 French ICUs of university, and general and private hospitals. After each intubation using Macintosh DL, patients’ and operators’ characteristics, Macintosh blade size, results of first DL and alternative techniques used, as well as the need of a second operator were collected. Complications rates associated with intubation were investigated. Primary outcome was success rate of first DL using Macintosh blade.

Results

A total of 2139 intubations were collected, 629 with a Macintosh blade No3 and 1510 with a No4. Incidence of first-pass intubation after first DL was significantly higher with Macintosh blade No3 (79.5 vs 73.3%, p = 0.0025), despite equivalent Cormack–Lehane scores (p = 0.48). Complications rates were equivalent between groups. Multivariate analysis concluded to a significant impact of Macintosh blade size on first DL success in favor of blade No3 (OR 1.44 [95% CI 1.14–1.84]; p = 0.0025) without any significant center effect on the primary outcome (p = 0.18). Propensity scores and adjustment analyses concluded to equivalent results.

Conclusion

In the present study, Macintosh blade No3 was associated with improved first-passed DL in French ICUs. However, study design requires the conduct of a nationwide prospective multicenter randomized trial in different settings to confirm these results.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00134-022-06832-9.