Parker Flex-It stylet is as effective as GlideRite Rigid stylet for orotracheal intubation by Glidescope

Tracheal tube introducer-associated airway trauma: a systematic review

BACKGROUND

Tracheal tube introducers are recommended in airway management guidelines and are used increasingly as videolaryngoscopy becomes more widespread. This systematic review aimed to summarise the published literature concerning tracheal tube introducer-associated airway trauma.

METHODS

PubMed, EMBASE and CINAHL databases were searched using pre-determined criteria. Two authors independently assessed search results and performed data extraction and risk of bias assessments.

RESULTS

We included 16 randomised controlled trials and five observational studies involving 10,797 patients. There was heterogeneity in patient characteristics, airway manipulation, and airway trauma definition and measurement. One study investigated hyperangulated videolaryngoscopy. The standard stylet was the most commonly reported introducer, followed by bougie and stylets with additional features such as video or lighted tip. Airway trauma resulted in low harm and most frequently involved injuries to the upper airway, followed by laryngeal and tracheobronchial injuries. Eighteen studies were comparative and reported a reduction in airway trauma incidence when an introducer was used, with the exception of the standard stylet. Median (IQR [range]) pooled incidence of airway trauma associated with standard stylets was 13.1% (4.2-31.4 [0.5-79.2])% and with bougies was 5.4% (0.4-49.9 [0.0-68.0])%. The risk of bias of included studies was variable and many randomised trials were found to be at high risk due to non-robust measurement of the outcome.

CONCLUSIONS

Stylets might be associated with an increased risk of airway trauma compared with other devices or when no stylet was used, though the quality of evidence is modest. However, other introducers appear to be safe and reduce the risk of airway trauma.

Dynamic versus standard bougies for tracheal intubation with direct or indirect laryngoscopy in simulated or real scenarios: a systematic review and meta-analysis

INTRODUCTION

This systematic review and meta-analysis aimed to compare the efficacy of dynamic versus standard bougies to achieve tracheal intubation.

METHODS

We searched MEDLINE, Embase, CENTRAL, Web of Science, Scopus and Google Scholar on 10 October 2023. We included clinical trials comparing both devices. The primary outcome was the first-attempt intubation success rate. The secondary outcome was the time required for tracheal intubation.

RESULTS

Eighteen studies were included. Dynamic bougies do not increase first-attempt success rate (RR 1.11; p = 0.06) or shorten tracheal intubation time (MD -0.30 sec; p = 0.84) in clinical trials in humans. In difficult airways, first-attempt success intubation rate was greater for dynamic bougies (RR 1.17; p = 0.002); Additionally, they reduced the time required for intubation (MD -4.80 sec; p = 0.001). First-attempt intubation success rate was higher (RR 1.15; p = 0.01) and time to achieve intubation was shorter when using Macintosh blades combined with dynamic bougies (MD -5.38 sec; p < 0.00001). Heterogeneity was high.

CONCLUSION

Dynamic bougies do not increase the overall first-pass success rate or shorten tracheal intubation time. However, dynamic bougies seem to improve first-attempt tracheal intubation rate in patients with difficult airways and in those intubated with a Macintosh blade. Further research is needed for definitive conclusions.

REGISTRATION OF PROSPERO

CRD42023472122.

Comparison of Rigid and Articulating Video Stylets During Simulated Endotracheal Intubation With Hyperangulated Video Laryngoscopy

BACKGROUND

Endotracheal tube delivery through the vocal cords can be challenging with hyperangulated video laryngoscopy due to the acute angle around the tongue and surrounding airway structures. Articulating video stylets may mitigate this issue by equipping an endotracheal tube stylet with an operator-controlled articulating end that has an additional camera at the tip.

OBJECTIVES

We compared operator-reported ease of intubation between the traditional rigid stylet (GlideRite^Ⓡ Rigid Stylet, Verathon Inc., Bothell, WA) and the articulating video stylet (ProVu™ Video Stylet, Flexicare Inc., Irvine, CA) with a hyperangulated video laryngoscope (GlideScope^Ⓡ, Verathon Inc., Bothell, WA).

METHODS

Participants performed simulated intubation using a hyperangulated video laryngoscope with both stylets in random order. We compared operator-reported ease of intubation on a 0-100 visual analogue scale (VAS), best percentage of glottic opening (POGO), and time to intubation. We compared outcomes using a paired t-test or the asymptotic Wilcoxon-Pratt signed-rank test dependent on normality.

RESULTS

We enrolled a convenience sample of 16 emergency department attendings, residents, and physician assistant postgraduate trainees. The median operator-reported ease of intubation on VAS was 20 (interquartile range 9, 30) for the rigid stylet and 20 (10, 30) for the articulating video stylet (p = 0.832). However, the rigid stylet had a slightly shorter mean time to intubation compared with the articulating video stylet, 6.9 (standard deviation 2.5) vs. 10.3 (4.1) s, respectively (p = 0.017). POGO was similar between groups.

CONCLUSIONS

During simulated endotracheal intubation, the rigid and articulating video stylets had similar operator-reported ease of intubation.

Comparison between GlideRite® rigid stylet and Parker Flex-It™ stylet to facilitate GlideScope intubation in simulated difficult intubation: a randomized controlled study

Background

The GlideScope^® videolaryngoscope (GVL) is widely used in patients with difficult airways and provides a good glottic view. However, the acute angle of the blade can make insertion and advancement of an endotracheal tube (ETT) more difficult than direct laryngoscopy, and the use of a stylet is recommended. This randomized controlled trial compared Parker Flex-It™ stylet (PFS) with GlideRite^® rigid stylet (GRS) to facilitate intubation with the GVL in simulated difficult intubations.

Methods

Fifty-four patients were randomly allocated to undergo GVL intubation using either GRS (GRS group) or PFS (PFS group). The total intubation time (TIT), 100-mm visual analog scale (VAS) for ease of intubation, success rate at the first attempt, use of laryngeal manipulation, tube advancement rate by assistant, and complications were recorded.

Results

There was no significant difference between the GRS and PFS groups regarding TIT (50.3 ± 12.0 s in the GRS group and 57.8 ± 18.8 s in the PFS group, P = 0.108). However, intubation was more difficult in the PFS group than in the GRS group according to VAS score (P = 0.011). Cases in which the ETT was advanced from the stylet by an assistant, were more frequent in the GRS group than in the PFS group (P = 0.002). The overall incidence of possible complications was not significantly different.

Conclusions

In patients with a simulated difficult airway, there was no difference in TIT using either the PFS or GRS. However, endotracheal intubation with PFS is more difficult to perform than GRS.

Discrimination ability of the endotracheal tube location using real-time palpation during intubation using an endotracheal tube with a preloaded stylet

Purpose

Palpation during intubation could be used as an ancillary method of providing real-time information of the endotracheal tube (ETT) placement before manual ventilation. This study aimed to evaluate the ability to discriminate the ETT location using a modified real-time palpation method with a preloaded stylet during intubation.

Patients and methods

The examiner performing the real-time palpation method placed three fingers on the lateral sides of the trachea between the sternal notch and the thyroid cartilage to determine if endotracheal intubation was successful. Endotracheal intubation was confirmed by auscultation and quantitative carbon dioxide waveform using capnography.

Results

Eighty-eight patients were enrolled in this study. The discrimination accuracy of the real-time palpation method was 98.9% (95% CI: 93.8–99.8) for identifying the location of ETT between the trachea and esophagus. There was one false negative, reported as esophageal intubation rather than tracheal intubation.

Conclusion

The real-time palpation method during intubation using an ETT with a preloaded stylet is an instantly applicable technique with good discrimination ability. The addition of real-time information through this palpation method to the conventional intubation process, especially in patients with poor vocal cord visualization, would be useful to facilitate the process of safe and careful endotracheal intubation.