Evaluation of the Storz CMAC®, Glidescope® GVL, AirTraq®, King LTS-D™, and direct laryngoscopy in a simulated difficult airway

Efficacy of Video Laryngoscopy versus Direct Laryngoscopy in the Prehospital Setting: A Systematic Review and Meta-Analysis

INTRODUCTION

Placing an endotracheal tube is a life-saving measure. Direct laryngoscopy (DL) is traditionally the default method. Video laryngoscopy (VL) has been shown to improve efficiency, but there is insufficient evidence comparing VL versus DL in the prehospital settings. This study, comprising a systematic review and random-effects meta-analysis, assesses current literature for the efficacy of VL in prehospital settings.

METHODS

PubMed and Scopus databases were searched from their beginnings through March 1, 2022 for eligible studies. Outcomes were the first successful intubation, overall success rate, and number of total DL versus VL attempts in real-life clinical situations. Cochrane's Risk of Bias (RoB) tool and the Newcastle-Ottawa Scale (NOS) were applied to assess risk of bias and study quality; Q-statistics and I2 values were used to assess heterogeneity.

RESULTS

The search yielded seven studies involving 23,953 patients, 6,674 (28%) of whom underwent intubation via VL. Compared to DL, VL was associated with a statistically higher risk ratio for first-pass success (Risk Ratio [RR] = 1.116; 95% CI, 1.005-1.239; P = .041; I2 = 87%). The I2 value for the subgroup of prospective studies was 0% compared to 89% for retrospective studies. In addition, VL was associated with higher likelihood of overall success rate (RR = 1.097; 95% CI, 1.01-1.18; P = .021; I2 = 85%) and lower mean number of attempts (Mean Difference = -0.529; 95% CI, -0.922 to -0.137; P = .008).

CONCLUSION

The meta-analysis suggested that VL was associated with higher likelihood of achieving first-pass success, greater overall success rate, and lower number of intubation attempts for adults in the prehospital settings. This study had high heterogeneity, likely presenced by the inclusion of retrospective observational studies. Further studies with more rigorous methodology are needed to confirm these results.

Comparison of Pentax-AWS®, Glidescope®, and King Vision® for difficult-airway intubation in manikins model by paramedics

Introduction:

Prehospital tracheal intubation of a difficult airway is challenging for paramedics. Thus far, the potential role of video laryngoscopes for this purpose has not been confirmed. Therefore, this study aimed to determine the impact of different types of video laryngoscopes on the success rate and time to intubation by paramedics.

Methods:

This is a prospective, randomized, crossover manikin study involving 18 paramedics. Participants performed intubation on a difficult airway in a high-fidelity manikin using Pentax-AWS®, Glidescope®, and King Vision® (with two blade types). Time to intubation and success rate of intubation were determined. Participants also rated the best glottic view and reported their preferences of devices.

Results:

In a difficult-airway scenario, the median time to intubation with Pentax-AWS® was 22.9 s (interquartile range, 19.5–24.9 s), which was significantly shorter than using other devices. There were no significant differences in the time to maximal exposure of the vocal cords between four devices ( p = 0.156). The time to insert the endotracheal tube with Pentax-AWS® and King Vision® with a guide-channel blade was significantly shorter than that with the other two devices (all, p < 0.05). Pentax-AWS® and King Vision® with a guide-channel blade showed higher success rates than the other two devices ( p = 0.04). With regard to device preference, 14 participants preferred Pentax-AWS® among all devices analyzed.

Conclusion:

Pentax-AWS® could be an appropriate device for paramedics in cases of difficult airways, with high success rate.

Learning and performance of endotracheal intubation by paramedical students: Comparison of GlideScope(®) and intubating laryngeal mask airway with direct laryngoscopy in manikins

Background and Aims:

GlideScope video laryngoscope (GVL) and intubating laryngeal mask airway (I-LMA) may be used to facilitate intubation and secure the airway in patients with normal and abnormal airways. The aim of this study was to evaluate whether (GVL) and (I-LMA) facilitate and improve the tracheal intubation success rate and could be learned and performed easily by paramedic students when compared with Macintosh direct laryngoscopy (DL).

Methods:

This study was a prospective, randomised crossover trial that included 100 paramedic students. Macintosh DL, I-LMA and GVL were tested in both normal and difficult airway scenarios. Each participant was allowed up to three intubation attempts with each device, in each scenario. The time required to perform tracheal intubation, the success rate, number of intubation attempts and of optimisation manoeuvres and the severity of dental trauma were recorded. Statistical analysis was performed using Chi-square, one-way ANOVA, or Kruskal-Wallis test as appropriate, followed by post hoc test.

Results:

GVL and I-LMA required less time to successfully perform tracheal intubation, showed a greater success rate of intubation, reduced the number of intubation attempts and optimization manoeuvres required and reduced the severity of dental trauma compared to Macintosh DL in both normal and difficult airway scenarios.

Conclusion:

GVL and I-LMA provide better airway management than Macintosh DL in both normal and difficult airway scenarios.

Evaluation of Karl Storz CMAC Tip™ device versus traditional airway suction in a cadaver model

Introduction

We compared the efficacy of Karl Storz CMAC Tip™ with inline suction to CMAC with traditional suction device in cadaveric models simulating difficult airways, using media mimicking pulmonary edema and vomit.

Methods

This was a prospective, cohort study in which we invited emergency medicine faculty and residents to participate. Each participant intubated 2 cadavers (one with simulated pulmonary edema and one with simulated vomit), using CMAC with inline suction and CMAC with traditional suction. Thirty emergency medicine providers performed 4 total intubations each in a crossover trial comparing the CMAC with inline suction and CMAC with traditional suction. Two intubations were performed with simulated vomit and two with simulated pulmonary edema. The primary outcome was time to successful intubation; and the secondary outcome was proportion of successful intubation.

Results

The median time to successful intubation using the CMAC with inline suction versus traditional suction in the pulmonary edema group was 29s and 30s respectively (p=0.54). In the vomit simulation, the median time to successful intubation was 40s using the CMAC with inline suction and 41s using the CMAC with traditional suction (p=0.70). There were no significant differences in time to successful intubation between the 2 devices. Similarly, the proportions of successful intubation were also not statistically significant between the 2 devices. The proportions of successful intubations using the inline suction were 96.7% and 73.3%, for the pulmonary edema and vomit groups, respectively. Additionally using the handheld suction device, the proportions for the pulmonary edema and vomit group were 100% and 66.7%, respectively.

Conclusion

CMAC with inline suction was no different than CMAC with traditional suction and was associated with no statistically significant differences in median time to intubation or proportion of successful intubations.