Utility of the Pentax-AWS® without interruption of chest compression: Comparison of the Macintosh laryngoscope with the Pentax-AWS® in manikin model

doi:10.1016/j.resuscitation.2009.09.031

Resuscitation

Volume 81, Issue 1, January 2010, Pages 69-73

https://doi.org/10.1016/j.resuscitation.2009.09.031 Get rights and content

Abstract

Background

Emergency airway management in suboptimal conditions can result in difficulties in tracheal intubation. The video laryngoscope (Pentax-AWS^®) has potential advantages during difficult tracheal intubations. According to the 2005 guidelines for cardiopulmonary resuscitation (CPR), all rescuers should minimize interruption of chest compressions. Our hypothesis is that tracheal intubation using the Pentax-AWS^® is possible without interruption of chest compressions. We tested this using tracheal intubation performed by less experienced medical personnel in a manikin model.

Methods

Thirty-two less experienced (<10 tracheal intubations) medical interns performed intubation using the Pentax-AWS^® and the Macintosh laryngoscope in an ALS simulator (Laerdal, Stavanger, Norway) in each of three scenarios. The three scenarios were: (1) normal airway without chest compression, (2) normal airway with continuous chest compression, and (3) difficult airway with continuous chest compression. The success rate, time required to complete tracheal intubation and to visualize vocal cords, POGO (percentage of glottic opening) score, dental compression and the ease of intubation were recorded.

Results

All participants performed successful intubation with the Pentax-AWS^® in the three scenarios. In the two continuous chest compression scenarios (scenarios 2 and 3), the success rate was significantly higher with the Pentax-AWS^® than with the Macintosh laryngoscope.

Conclusions

The Pentax-AWS^® was an effective tool for endotracheal intubation during chest compression performed by less experienced medical personnel in a manikin model simulating cardiac arrest, both under conditions of normal and difficult airways.

Introduction

Standard direct laryngoscopic tracheal intubation remains the preferred technique to establish advanced airway management. However, sufficient experience is required to be proficient in using this technique. In an emergency situation, airway management is often performed by a less experienced physician, particularly under suboptimal conditions. This may affect a patient's morbidity.1, 2 Introduction of tracheal intubation by video laryngoscope might have benefits in these situations.3, 4, 5, 6, 7, 8

The Pentax-AWS^® system (AWS; Pentax Corporation, Tokyo, Japan) is a newly developed portable video laryngoscope that is designed for tracheal intubation under normal and difficult airway situations. It consists of a camera, a monitor, and a disposable blade (PBlade^®). The PBlade^® is designed to provide a view of the glottis without alignment of the oral, pharyngeal, and laryngeal axes and has a channel on its right side by which it holds and guides the endotracheal tube (ETT). Previous studies have demonstrated that the Pentax-AWS^® improves the glottic view and is the device of choice among several video laryngoscopes.4, 6, 8, 9, 10, 11, 12

Several animal studies have shown that frequent or prolonged interruption of chest compressions is associated with reduced coronary perfusion pressure, reduced return of spontaneous circulation, reduced survival rates, and reduced post-resuscitation myocardial function.13, 14, 15, 16 The 2005 American Heart Association (AHA) guidelines for cardiopulmonary resuscitation (CPR) and emergency cardiac care (ECC) recommend that all rescuers should minimize interruption of chest compression for checking the pulse, analyzing rhythm, or performing other activities such as insertion of advanced airway management or use of a defibrillator.

Our hypothesis is that tracheal intubation via the Pentax-AWS^® system is possible during cardiopulmonary resuscitation without interruption of chest compressions. To test our hypothesis, tracheal intubation was performed by less experienced medical personnel (doctors applying for medical internship in our hospital) using a manikin model (ALS simulator, Laerdal, Stavanger, Norway).

Section snippets

Methods

After approval from the Institutional Review Board at our hospital, written informed consent was obtained from 32 participants. All participants had limited clinical experience in real patients. Before recruitment into our study, 15 participants had never attempted tracheal intubation in real patients. Although the other 17 volunteers had some prior experience of tracheal intubation, while they were students they had performed fewer than 10 tracheal intubations (2.76 ± 2.88) under the supervision

Results

Thirty-two participants (medical interns) who had performed fewer than 10 tracheal intubations were enrolled in this study. The majority of the participants were male (n = 21, 65.6%). The mean age of participants was 27.4 (±1.95) years, the mean height was 168 (±7.80) cm and the mean weight was 61.7 (±11.24) kg. No participants had prior experience with the Pentax-AWS^®.

Discussion

As a result of recent advances in video technology and in fiber optic systems, several kinds of video laryngoscopes have been introduced. Recent studies showed that the video laryngoscope is superior to a conventional laryngoscope in enabling a glottic view, in success rate, and in management of difficult airways.3, 5, 7, 17, 18, 19 Pott and Murray suggested that the management of potentially difficult intubations is likely to change through the use of video laryngoscopes.⁴ Malik et al.

Conclusion

Less experienced medical personnel were able to successfully perform endotracheal intubation without interruption of chest compression in a manikin model simulating cardiac arrest under conditions of both normal and difficult airways. Further validation of the Pentax-AWS^® in the clinical setting is required.

Conflict of interest

No author has any conflict of interest in regard to devices and finance.

Funding

This article was not financially supported by any company or organization.

Acknowledgement

The authors thank Dr. Imju Kang, who is a certified BLS provider at Kangbuk Samsung Hospital, for his contribution to this study.

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Cited by (36)

Comparison of video laryngoscopy versus direct laryngoscopy for intubation in emergency department patients with cardiac arrest: A multicentre study
2019, Resuscitation
To compare the tracheal intubation performance between video laryngoscopy (VL) and direct laryngoscopy (DL) in patients with cardiac arrest in the ED.
This is an analysis of the data from a prospective, multicentre study of 15 EDs in Japan. We included consecutive adult patients with cardiac arrest who underwent intubation with VL or DL from 2012 through 2016. The primary outcome was first-attempt success. The secondary outcomes were glottic visualisation assessed with Cormack grade (1 vs. 2–4) and occurrence of oesophageal intubation. To examine the between-device difference in outcome risks, we analysed the whole data and 1:1 propensity score matched data.
Among 9694 patients who underwent intubation in the EDs, 3360 cardiac arrests (35%) were included in the analysis (90% were non-traumatic cardiac arrests). The first-attempt success rate was higher in the VL group compared to those in the DL (78% vs 70%; unadjusted OR 1.61 [95%CI 1.26–2.06] P < 0.001). This association remained significant after adjusting for six potential confounders and within-ED clustering (adjusted OR 1.33 [95%CI 1.03–1.73] P = 0.03). VL use was also associated with a better glottic visualisation (adjusted OR 3.84 [95%CI 2.81–5.26] P < 0.001) and lower rate of oesophageal intubation (adjusted OR 0.45 [95%CI 0.24–0.85] P = 0.01) compared to DL. These results were consistent in the propensity score matched analysis.
Based on large multicentre prospective data of ED patients with cardiac arrest, the use of VL was associated with a higher first-attempt success rate compared to DL, with a better glottic visualisation and lower oesophageal intubation rate.
C-MAC compared with direct laryngoscopy for intubation in patients with cervical spine immobilization: A manikin trial
2017, American Journal of Emergency Medicine
The aim of this study was to compare C-MAC videolaryngoscopy with direct laryngoscopy for intubation in simulated cervical spine immobilization conditions.
The study was designed as a prospective randomized crossover manikin trial. 70 paramedics with < 5 years of medical experience participated in the study. The paramedics attempted to intubate manikins in 3 airway scenarios: normal airway without cervical immobilization (Scenario A); manual inline cervical immobilization (Scenario B); cervical immobilization using cervical extraction collar (Scenario C).
Scenario A: Nearly all participants performed successful intubations with both MAC and C-MAC on the first attempt (95.7% MAC vs. 100% C-MAC), with similar intubation times (16.5 s MAC vs. 18 s C-MAC). Scenario B: The results with C-MAC were significantly better than those with MAC (p < 0.05) for the time of intubation (23 s MAC vs. 19 s C-MAC), success of the first intubation attempt (88.6% MAC vs. 100% C-MAC), Cormack-Lehane grade, POGO score, severity of dental compression, device difficulty score, and preferred airway device. Scenario C: The results with C-MAC were significantly better than those with MAC (p < 0.05) for all the analysed variables: success of the first attempt (51.4% MAC vs. 100% C-MAC), overall success rate, intubation time (27 s MAC vs. 20.5 s C-MAC), Cormack-Lehane grade, POGO score, dental compression, device difficulty score and the preferred airway device.
The C-MAC videolaryngoscope is an excellent alternative to the MAC laryngoscope for intubating manikins with cervical spine immobilization.
Video laryngoscopy vs. direct laryngoscopy: Which should be chosen for endotracheal intubation during cardiopulmonary resuscitation? A prospective randomized controlled study of experienced intubators
2016, Resuscitation
This study compared endotracheal intubation (ETI) performance during cardiopulmonary resuscitation (CPR) between direct laryngoscopy (DL) and video laryngoscopy (VL) (GlideScope^®) by experienced intubators (>50 successful ETIs).
This was a prospective randomized controlled study conducted in an emergency department between 2011 and 2013. Intubators who used DL or VL were randomly allocated to ETI during CPR. Data were collected from recorded video clips and rhythm sheets. The success, speed, complications, and chest compressions interruption were compared between the two devices.
Total 140 ETIs by experienced intubators using DL (n = 69) and VL (n = 71) were analysed. There were no significant differences between DL and VL in the ETI success rate (92.8% vs. 95.8%; p = 0.490), first-attempt success rate (87.0% vs. 94.4%; p = 0.204), and median time to complete ETI (51 [36–67] vs. 42 [34–62] s; p = 0.143). In both groups, oesophageal intubation and dental injuries seldom occurred. However, longer chest compressions interruption occurred using DL (4.0 [1.0–11.0] s) compared with VL (0.0 [0.0–1.0] s) and frequent serious no-flow (interruption > 10 s) occurred with DL (18/69 [26.1%]) compared with VL (0/71) (p < 0.001). For highly experienced intubators (>80 successful ETIs), frequent serious no-flow occurred in DL (14/55 [25.5%] vs. 0/57 in VL).
The ETI success, speed and complications during CPR did not differ significantly between the two devices for experienced intubators. However, the VL was superior in terms of completion of ETI without chest compression interruptions.
Clinical Research Information Service (CRIS) in South Korea KCT0000849.
Performance of intubation with 4 different airway devices by unskilled rescuers: Manikin study
2015, American Journal of Emergency Medicine
Citation Excerpt :
Because TTV with the iGEL was nearly half that with the LMA, in terms of time management, we suggest the iGEL may be more useful for rapid airway establishment. Although many previous surveys on intubation with the AWS in comparison with the MCL or other VLs [7-20], to our knowledge, there are no reports comparing the performance of the AWS with SADs. In line with previous results, intubation with the AWS had a longer TTV than the SADs in this study.
This study was designed to compare the performances of 4 airway devices in achieving successful ventilation.
A randomized crossover trial was conducted to evaluate 4 airway devices: laryngeal mask airway (LMA), i-gel (iGEL), PENTAX Airway Scope (AWS), and Macintosh laryngoscope (MCL). Thirty-eight unskilled rescuers performed intubation on a manikin during chest compressions in normal and difficult airway scenarios. The time to ventilation, intubation success rate, and difficulty of intubation were measured.
The time to ventilation of the airway devices in the normal scenario had a median value of 8.8 seconds (interquartile range, 7.3-10.5 seconds) for iGEL, 16.1 seconds (13.9-19.3 seconds) for LMA, 30.6 seconds (24.6-37.6 seconds) for AWS, and 35.0 seconds (29.5-45.9 seconds) for MCL. In the difficult airway scenario, the respective time to ventilation was 8.6 seconds (7.8-10.0 seconds), 15.3 seconds (14.3-20.2 seconds), 29.4 seconds (25.7-36.3 seconds) and 59.0 seconds (46.1-103.3 seconds). The success rates were 100% and 100% for LMA, 100% and 100% for iGEL, 97.4% and 94.7% for AWS, and 78.9% and 47.4% for MCL in the normal and difficult airway scenarios. The difficulties of intubation expressed as numerical rating scale were 2.0 and 2.0 (median values) for LMA, 1.0 and 2.0 for iGEL, 3.0 and 3.0 for AWS, and 4.0 and 5.0 for MCL in the normal and difficult airway scenarios, respectively.
With novice intubators who were unfamiliar with the airway devices, the LMA, iGEL, and AWS were superior to the MCL for establishing an airway without interruption of chest compressions in a manikin study. Intubation with the iGEL was faster and easier than with the other airway devices.
Simulated endotracheal intubation of a patient with cervical spine immobilization during resuscitation: A randomized comparison of the Pentax AWS, the Airtraq, and the McCoy Laryngoscopes
2015, American Journal of Emergency Medicine
Tracheal intubation during cardiopulmonary resuscitation is a high-risk procedure. The aim of this study was to compare efficacy of intubation with the Pentax AWS, Airtraq, and McCoy laryngoscopes in patients with cervical spine immobilization during resuscitation in a randomized, controlled simulation trial.
We compared times to intubation, success rate, Cormack and Lehane grading, and ease of intubation when using Pentax AWS, Airtraq, and McCoy in randomized order.
Sixty-seven paramedics were trained in the use of the Pentax AWS, Airtraq, and McCoy laryngoscopes with a METIman Prehospital manikin. Participants performed tracheal intubation in patients with cervical spine immobilization during resuscitation scenario. We measured success rates, times for tracheal intubation, the glottic view, and ease of intubation.
The primary study end point, overall success rate, was highest when using Pentax AWS (94.0%) and was lower in Airtraq (86.6%; P = .017) and in McCoy (85.1%; P = .019). Time to first effective ventilation was achieved significantly shorter when using Pentax AWS (25.4 ± 6.7 seconds) than Airtraq (35.6 ± 5.1 seconds; P < .001) or McCoy (38.5 ± 10.3 seconds; P < .001). The quality of glottic view and ease of use were best with Pentax AWS.
The Pentax AWS videolaryngoscope provided a better view of the vocal cords, less insertion time, and higher success rate of the endotracheal intubation compared with the Airtraq or McCoy laryngoscopes in adults with simulated cervical spine immobilization during resuscitation.
Comparison of the pentax, truview, glidescope, and the miller laryngoscope for child intubation during resuscitation
2015, American Journal of Emergency Medicine
Citation Excerpt :
Median time until final placement was 20.6 (IQR, 18-27) seconds. Han et al [13] during intubation of an adult with simultaneous chest compression found that the overall effectiveness of intubation using Pentax-AWS was 100%, and time to intubation was 13.5 seconds. One hundred percent effectiveness of Pentax-AWS during intubation also replicates the studies of Komasawa et al [10].
The study was designed to compare the effectiveness of 3 video laryngoscopes with the Miller laryngoscope during pediatric resuscitation.
This was a randomized crossover study involving 87 paramedics and 54 nurses. The primary end point of the study was the success rate of blind tracheal intubation, whereas the secondary end point was defined as the time from insertion of a device to the first manual ventilation of the manikin's lungs.
The median time to intubation using the Pentax, Truview, GlideScope, and Miller varied with the times being 20.6 (interquartile range [IQR], 18-27) vs 20.1 (IQR, 18-23.3) vs 30.2 (IQR, 29.6-35) vs 41.3 (IQR, 33-45.2) seconds, respectively. The overall success ratios of intubation for the devices were 100% vs 100% vs 100% vs 79.4%.
We concluded that, in a pediatric manikin scenario, the video laryngoscopes are safe devices and can be used for pediatric intubation during uninterrupted chest compressions. Further clinical studies are necessary to confirm these initial positive findings.

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^☆: A Spanish translated version of the abstract of this article appears as Appendix in the final online version at doi:10.1016/j.resuscitation.2009.09.031.

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Simulation and educationUtility of the Pentax-AWS® without interruption of chest compression: Comparison of the Macintosh laryngoscope with the Pentax-AWS® in manikin model☆

Abstract

Background

Methods

Results

Conclusions

Introduction

Section snippets

Methods

Results

Discussion

Conclusion

Conflict of interest

Funding

Acknowledgement

J Clin Anesth

Br J Anaesth

Br J Anaesth

Ann Emerg Med

Ann Emerg Med

Br J Anaesth

Resuscitation

Emergency tracheal intubation: complications associated with repeated laryngoscopic attempts

Anesth Analg

Evaluation of ease of intubation with the GlideScope or Macintosh laryngoscope by anaesthetists in simulated easy and difficult laryngoscopy

Anaesthesia

Review of video laryngoscopy and rigid fiberoptic laryngoscopy

Curr Opin Anaesthesiol

Simulation and education
Utility of the Pentax-AWS^® without interruption of chest compression: Comparison of the Macintosh laryngoscope with the Pentax-AWS^® in manikin model☆