A Comparison of McGrath MAC, AIRWAY SCOPE®, and AceScope® Video laryngoscopes in Novice Healthcare Providers: A Randomized Crossover Simulation Study

A Comparison of McGrath MAC, AIRWAY SCOPE®, and AceScope® Video laryngoscopes in Novice Healthcare Providers: A Randomized Crossover Simulation Study | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article A Comparison of McGrath MAC, AIRWAY SCOPE®, and AceScope® Video laryngoscopes in Novice Healthcare Providers: A Randomized Crossover Simulation Study Musashi Yahagi, Kyuma Omi, Yuichi Yaguchi This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-4684340/v1 This work is licensed under a CC BY 4.0 License Status: Published Journal Publication published 25 Apr, 2025 Read the published version in BMC Anesthesiology → Version 1 posted 4 You are reading this latest preprint version Abstract 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 seconds and 23.80 ± 2.43 seconds, 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 comparable among the devices, with one notable exception between the AceScope and McGrath MAC in scenario of tracheal intubation using AceScope in a cervical spine immobilization model. 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. Figures Figure 1 Figure 2 Figure 3 Introduction Video laryngoscopes have revolutionized tracheal intubation by offering enhanced visualization of the airway, particularly in challenging airway scenarios. The McGrath MAC (Aircraft Medical Ltd, Scotland, United Kingdom) and AIRWAY SCOPE® (Pentax Corporation, Tokyo, Japan) are two widely employed video laryngoscopes that have demonstrated efficacy in tracheal intubation across diverse clinical situations. 1, 2, 3 The AceScope® (IMI Co., Ltd., Seoul, Korea), a novel video laryngoscope, combines the McGrath MAC's optimal glottic visualization with the AIRWAY SCOPE's disposable blade and guide rail system, offering a sleek, lightweight design that promotes ease of use and maneuverability. 4 Despite its innovative design, there is limited clinical evidence comparing the effectiveness and usability of the AceScope with other prevalent video laryngoscopes. 5, 6 The primary objective of this study is to evaluate and compare the performance of the AceScope, McGrath MAC, and AIRWAY SCOPE in terms of intubation success rate and time to intubation during simulated tracheal intubation scenarios in novice healthcare providers using a manikin. Additionally, the study aims to assess user preferences and device ease of use as secondary outcomes in both simulated normal and difficult airway situations. This comparative analysis will help determine whether the AceScope provides any distinct advantages over the other two video laryngoscopes, thereby contributing to the optimization of airway management strategies. Materials and Methods After obtaining approval from the Ethics Committee of Hitachi General Hospital (Approval No. 2023-22, Clinical Research Registry No. UMIN000050394), written informed consent was secured from 60 nurses and pharmacists lacking prior tracheal intubation experience to participate in this randomized crossover study. The novices received verbal and demonstrative instruction from a board-certified anesthesiologist in Japan on the utilization of three types of video laryngoscopes (McGrath MAC, AIRWAY SCOPE, and AceScope). A malleable stylet was inserted into the endotracheal tube (ETT) and bent into a "field hockey stick" shape for intubation with the McGrath MAC. 7,8 In this study, two types of airway management simulators, the Laerdal Airway Management Trainer (Laerdal Medical, Stavanger, Norway), were prepared: a "normal airway model" that allowed subjects to freely and arbitrarily adjust the simulator's inherent head extension angle, and a "Cervical Spine Immobilization Model," which was a custom-made difficult airway version created by the principal investigator. 9,10 The latter involved attaching a cervical spine protection collar for adults to the neck of the airway management simulator, rendering head extension impossible. Subsequently, participants were provided with five minutes of free training time for each device. Those who could not successfully intubate the trachea using at least one of the three video laryngoscopes were excluded from the study. A random order of the following six intubation scenarios was generated using a random number generator ( https://www.random.org ) by a physician distinct from the one who demonstrated tracheal intubation: 1) intubation with McGrath MAC in a normal airway model, 2) intubation with McGrath MAC in a cervical immobilization model, 3) intubation with AIRWAY SCOPE in a normal airway model, 4) intubation with AIRWAY SCOPE in a cervical immobilization model, 5) tracheal intubation using AceScope in a normal airway model, and 6) tracheal intubation using AceScope in a fixed cervical spine model. During the tracheal intubation scenarios, participants were permitted to request assistance from an assistant anesthesiologist at their discretion, starting 30 seconds after initiating the procedure. 11 The assistant could help with reinserting the laryngoscope, holding and supporting the laryngoscope, and adjusting the head position, and the number of instances in which the assistant provided aid was recorded. However, assistants were not allowed to touch the ETT. Upon completing all six scenarios, participants rated the ease of tracheal intubation for each device on a visual analog scale, with 0 signifying "extremely easy" and 10 denoting "extremely difficult." The primary endpoint in this study was the duration of successful tracheal intubation. Intubation time was defined as the interval from the blade's entry between the teeth until the ETT was connected to the bag-valve mask and the model lung inflated. 9, 12 All intubation procedures were video-recorded. The position of the ETT tip was verified by the principal investigator following each intubation. Failure of intubation was defined as a time delay exceeding 120 seconds or inflation of the model stomach without inflating the model lung when utilizing the bag-valve mask. Secondary endpoints included the frequency of assistance required for successful intubation and the incidence of dental injuries (audible maxillary teeth clicking sounds). 13 Sample size calculations for this study were based on previous research comparing video laryngoscopes. 9, 12, 14 Assuming an average intubation time of 40 seconds with a standard deviation of 10 seconds, a sample size of 7 participants per group was determined to be necessary for detecting a minimum difference of 10 seconds in intubation time between groups, with a statistical power of 0.80 and an alpha level of 0.05. To account for potential dropouts and ensure an adequate sample size for each of the three devices, the study aimed to enroll 60 novice healthcare providers, comprising both nurses and pharmacists. Statistical Analysis: Statistical analyses were conducted using Stata version 17.1 (StataCorp, College Station, TX, USA). Data normality was assessed using the Shapiro-Wilk test. As intubation time data were normally distributed, they were presented as means ± standard deviations. Differences in intubation time among devices were analyzed using repeated measures analysis of variance (ANOVA), followed by post-hoc tests with Bonferroni correction. Primary outcome measures included intubation times for each device in every scenario. Secondary outcome measures encompassed user preferences and ease of use for each device based on visual analog scale scores, the incidence of dental injuries, and the frequency of assistance required during intubation procedures. These outcomes were analyzed using descriptive statistics, such as means and standard deviations for continuous variables and proportions for categorical variables. The statistical significance of differences in outcomes among devices was determined using ANOVA or chi-square tests, as appropriate. Post-hoc comparisons were performed using Bonferroni-corrected pairwise comparisons, with a significance level set at p < 0.05. All statistical tests were two-tailed. Results The study involved 60 healthcare professionals with a median age of 32 years (interquartile range: 26 - 42 years), consisting of 35% males and 65% females, and including 71.7% nurses and 28.3% pharmacists. The objective was to compare intubation times using McGrath MAC, AIRWAY SCOPE, and AceScope video laryngoscopes in both normal airway and cervical spine immobilization models. Novice operators performed tracheal intubation with each device, and a repeated measures ANOVA was conducted on the intubation times for the three groups among 55 participants. Prior to the study, all fifty-five participants successfully completed tracheal intubation in all six scenarios after receiving a 5-minute demonstration and 15 minutes of hands-on training (5 minutes per device). Five participants were excluded due to difficulties handling the devices in the cervical spine immobilization model: three were unable to independently perform tracheal intubation using AceScope, and two were unable to independently perform tracheal intubation using McGrath MAC. In the normal airway model, the analysis revealed a significant effect of the device on intubation time (F(2, 54) = 8.358, p = 0.0002). The mean intubation times (SD) for the McGrath MAC, AIRWAY SCOPE, and AceScope groups were 18.67 (1.44), 14.90 (1.76), and 24.16 (2.49) seconds, respectively. Post-hoc comparisons using the Bonferroni correction demonstrated significant differences in intubation time between the McGrath MAC and AIRWAY SCOPE groups (p < 0.05), and between the AIRWAY SCOPE and AceScope groups (p 0.05). In the cervical spine immobilization model, the repeated measures ANOVA indicated a significant effect of the device on intubation time (F(2, 57) = 7.04, p = 0.0007). The mean intubation times (SD) for the McGrath MAC, AIRWAY SCOPE, and AceScope groups were 26.33 (2.06), 23.80 (2.43), and 33.38 (2.50) seconds, respectively, with significant differences in intubation time among all three groups (McGrath MAC vs. AIRWAY SCOPE: p < 0.05, McGrath MAC vs. AceScope: p < 0.05, AIRWAY SCOPE vs. AceScope: p < 0.05) (Figure 2). Table 1 presents the outcomes of the study, examining the success rates for intubation, the necessity for intubation assistance, and the incidence of dental injuries (quantified by the number of clicks) for each scenario. McGrath MAC, AIRWAY SCOPE and AceScope video laryngoscopes were all employed with both normal and cervical spine immobilization models in this study. In scenario 4, a single case of esophageal intubation occurred, while in scenario 6, there were two instances of esophageal intubation and time up. Participants assessed the difficulty of tracheal intubation using each device on a visual analog scale (VAS), and no significant differences in VAS ratings were observed among the devices (Figure 3). No significant differences in dental injury incidence were found among the McGrath MAC, AIRWAY SCOPE and AceScope in both normal and cervical spine immobilization models, except for a notable difference in dental injury rate between the AceScope and McGrath MAC in scenario 6 (23.6%, p = 0.04) (Table 1). Table 1: Outcomes of a Study Investigating Endotracheal Intubation Scenarios Utilizing Various Videolaryngoscopes. Scenario Failed / Success (Success rate) Intubation Assistance Required Dental Injuries (number of clicks) No injury 1 2 3 1 (McGrath MAC normal) 0 / 55 (100%) 3 (device hold) 60 0 0 0 2 (McGrath MAC difficult) 0 / 55 (100%) 7 (device hold) 53 4 1 2 3 (AIRWAY SCOPE normal) 0 / 55 (100%) 2 (one head support, one device hold) 59 1 0 0 4 (AIRWAY SCOPE difficult) 1 † / 54 (98.2%) 12 (six device hold, six device repositioning) 51 4 4 1 5 (AceScope normal) 0 / 55 (100%) 10 (five head repositioning, four device hold, one device repositioning) 57 2 0 1 6 (AceScope difficult) 2 † / 53 (96.3%) 18 (sixteen device hold, two device repositioning) 47* 4 6 3 Table 1 presents the outcomes of a study examining six distinct endotracheal intubation scenarios employing various videolaryngoscope devices. The success rates for intubation, the necessity for intubation assistance, and the incidence of dental injuries (quantified by the number of clicks) were documented. The McGrath MAC, AIRWAY SCOPE, and AceScope devices were all employed with both normal and cervical spine immobilization models in this study. In scenario 4, a single case of esophageal intubation occurred, while in scenario 6, there were two instances of esophageal intubation and time up. Abbreviations:†, esophageal intubation or time up; *, significant difference in dental injury rate between AceScope and McGrath MAC (p = 0.04). Discussion This study aimed to compare the effectiveness and usability of McGrath MAC, AIRWAY SCOPE, and AceScope video laryngoscopes during simulated tracheal intubation scenarios in novice healthcare providers. Our results demonstrated significant differences in intubation times among the three devices in both normal and cervical spine immobilization models. In the normal airway model, the AIRWAY SCOPE had the shortest intubation time, followed by the McGrath MAC and AceScope. In the cervical spine immobilization model, intubation times were significantly longer, with the AIRWAY SCOPE remaining the fastest, followed by the McGrath MAC and AceScope. These findings suggest that the AIRWAY SCOPE may be more efficient than the other two devices, particularly in challenging airway situations. This could be attributed to the AIRWAY SCOPE's unique design, which features a disposable blade and guide rail system that facilitates smooth endotracheal tube insertion. 15, 16 Previous studies have also reported the AIRWAY SCOPE's superiority in terms of intubation time compared to other video laryngoscopes. 17, 18, 19, 20 However, it is crucial to consider that the differences in intubation times might not be clinically significant, as all devices demonstrated a high success rate in both normal and difficult airway models. In terms of secondary outcomes, our study found that novice users reported similar levels of difficulty using three different video laryngoscopes based on their assessments using a visual analog scale (VAS). However, it should be noted that healthcare providers with varying levels of experience may have different experiences with these devices. Notably, the AceScope's user-friendly design may make it easier to use, underscoring the importance of appropriate training and practical experience in increasing healthcare providers' confidence and comfort when using these devices. 21, 22 The incidence of dental injuries was comparable among the McGrath MAC, AIRWAY SCOPE, and AceScope in both normal airway and cervical spine immobilization models, with the exception of a significant difference between the AceScope and McGrath MAC in scenario 6. It is important to note that dental injuries during tracheal intubation are a significant concern, as they can lead to patient discomfort, complications, and potential medicolegal issues. 23, 24 While the differences in dental injury rates observed in this study were minimal, further investigation into the factors contributing to these discrepancies may help identify strategies to reduce dental injury risk during intubation. 25 The AceScope is a novel video laryngoscope that combines the most advantageous features of the McGrath MAC and AIRWAY SCOPE, providing a lightweight design that facilitates ease of use and maneuverability. 4 Although the AceScope demonstrated longer intubation times in both normal and cervical spine immobilization models compared to the other devices, it is crucial to consider that the differences may not be clinically significant, given that all devices achieved high success rates (Fig. 2 ). The AceScope's blade shape is similar to that of the McGrath MAC, and its guide rail system is reminiscent of the unique feature of the AIRWAY SCOPE. These design features may potentially facilitate smooth endotracheal tube insertion and optimal glottic visualization. However, additional investigation is necessary to assess the effects of these characteristics on intubation outcomes. It is worth noting that the AceScope's longer intubation times may result from its unique design, which may require novices to adjust to a new technique, leading to longer intubation times. Subsequent studies should evaluate the effectiveness of the AceScope among providers with varying levels of experience to determine whether it offers any distinct advantages over the other two video laryngoscopes. Overall, the AceScope's innovative design warrants further investigation to determine its potential role in airway management strategies. This study has some limitations that should be acknowledged. Firstly, the use of a manikin model may not fully represent the complexities and challenges of intubating human subjects, particularly in difficult airway scenarios. 9, 12, 14, 17, 20, 25 Therefore, the generalizability of our findings to clinical practice should be approached cautiously. Secondly, the study only involved novice healthcare providers, and the results may not be applicable to experienced providers. 9, 26, 27 Future studies should examine the performance of these devices among providers with varying levels of experience to determine their effectiveness across a broader spectrum of healthcare professionals. In conclusion, our findings demonstrate that the AIRWAY SCOPE was the most efficient video laryngoscope in terms of intubation time, both in normal airway and cervical spine immobilization models, followed by the McGrath MAC and AceScope. However, all devices exhibited high success rates, and there were no significant differences in perceived difficulty among the three video laryngoscopes. Further research is needed to validate these findings in clinical settings and investigate the impact of device-specific features on intubation outcomes, as well as dental injury incidence. Declarations Ethics approval and consent to participate This study was approved by the Ethics Committee of Hitachi General Hospital (approval number 2023-22) and registered as a clinical trial with the registration number UMIN000050394. (https://center6.umin.ac.jp/cgi-open-bin/ctr/ctr_view.cgi?recptno=R000057382) The registration date of the clinical trial is February 21, 2023. Informed consent was obtained from all individual participants included in the study. Consent for publication Written consent for publication was obtained from all individual participants included in the study. Availability of data and materials All data generated or analysed during this study are included in this published article and its supplementary information files. Competing interests The authors declare that they have no competing interests. Funding Support was provided solely from institutional and departmental sources. Authors' contributions Y.Y. and M.Y. designed the study. Y.Y. and K.O. performed the data collection and analysis. M.Y. wrote the manuscript draft. Both authors reviewed and approved the final manuscript. Acknowledgements The authors would like to express their gratitude to Professor Makoto Tanaka (M.D. Dean, College of Medicine, School of Health Sciences Professor and Chairman Department of Anesthesiology Institute of Clinical Medicine, University of Tsukuba, Tsukuba-city, Ibaraki, JAPAN) for his valuable guidance and support. References Chen YY, Lin JC, Tsai MJ, Cheng KY. 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Additional Declarations No competing interests reported. Supplementary Files file.xlsx Cite Share Download PDF Status: Published Journal Publication published 25 Apr, 2025 Read the published version in BMC Anesthesiology → Version 1 posted Editorial decision: Revision requested 13 Nov, 2024 Editor assigned by journal 09 Jul, 2024 Submission checks completed at journal 09 Jul, 2024 First submitted to journal 04 Jul, 2024 You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-4684340","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":328170079,"identity":"7ff7c607-73a1-4fb0-a5be-d45d7e40974b","order_by":0,"name":"Musashi Yahagi","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA8UlEQVRIiWNgGAWjYBADHvvDjI0PGBgOwPiEtcgxHGc+bECSFmOG82xpEggteIDujPSHH3+2bUtsbOYxq+apuSPHz8D88AGDzB2cWsxu5BhL87bdTmxm5jG7zXPsmbFkA5uxAQPPM3xaGKQZgVrawFrYDiduOMDDJsHAcxiPlvTHP38CtfQAtRTz/CNKS4KZBNBhxhLMbGnMvG3EaDnzxsya59xtOQNm5sOSc/sOG0s2A/2SgM8vx9Mf3/xRdpvHgP9g44c33w7L8bM3P3zwsQd3iKEAJnAEMgNxYs8B4rQw/oAzfxCpZRSMglEwCkYCAAA7qVb37FmsDgAAAABJRU5ErkJggg==","orcid":"","institution":"Hitachi General Hospital","correspondingAuthor":true,"prefix":"","firstName":"Musashi","middleName":"","lastName":"Yahagi","suffix":""},{"id":328170080,"identity":"189321a7-0870-4062-95b1-63b877f607ec","order_by":1,"name":"Kyuma Omi","email":"","orcid":"","institution":"Hitachi General Hospital","correspondingAuthor":false,"prefix":"","firstName":"Kyuma","middleName":"","lastName":"Omi","suffix":""},{"id":328170082,"identity":"e7a0b1af-20ef-4915-b3fb-9ebbcf9b5f8e","order_by":2,"name":"Yuichi Yaguchi","email":"","orcid":"","institution":"Hitachi General Hospital","correspondingAuthor":false,"prefix":"","firstName":"Yuichi","middleName":"","lastName":"Yaguchi","suffix":""}],"badges":[],"createdAt":"2024-07-04 06:54:43","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-4684340/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-4684340/v1","draftVersion":[],"editorialEvents":[{"content":"https://doi.org/10.1186/s12871-025-03094-y","type":"published","date":"2025-04-25T15:58:22+00:00"}],"editorialNote":"","failedWorkflow":false,"files":[{"id":62153872,"identity":"3942c92e-d4cd-46f3-9a8b-4e9d062766e0","added_by":"auto","created_at":"2024-08-09 20:55:03","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":1655874,"visible":true,"origin":"","legend":"\u003cp\u003eComparison of three video laryngoscope models and their corresponding disposable plastic blades.\u003c/p\u003e\n\u003cp\u003ea: A collective view of the three video laryngoscopes, arranged from left to right: McGrath MAC, AceScope, and AIRWAY SCOPE.\u003c/p\u003e\n\u003cp\u003eb: The disposable plastic blades compatible with each of the three video laryngoscopes, displayed from left to right: McGrath MAC blade (size #3, blade effective length 114mm), AceScope blade (size #3, blade effective length 133.4mm), and AIRWAY SCOPE blade (Depth 95mm, Height 134mm, Width 52mm).\u003c/p\u003e","description":"","filename":"Figure1bladeofvideolaryngoscope49.png","url":"https://assets-eu.researchsquare.com/files/rs-4684340/v1/96ffcac5459a877be3871c92.png"},{"id":62155130,"identity":"157e6f73-291d-4634-8b73-6db1eb9628d9","added_by":"auto","created_at":"2024-08-09 21:03:03","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":28175,"visible":true,"origin":"","legend":"\u003cp\u003eSix box-and-whisker plots illustrating intubation times in seconds for six scenarios involving McGrath MAC, AIRWAY SCOPE, and AceScope video laryngoscope in normal airway and cervical immobilization models. Scenario 1) intubation with McGrath MAC in a normal airway model, 2) intubation with McGrath MAC in a cervical immobilization model, 3) intubation with AIRWAY SCOPE in a normal airway model, 4) intubation with AIRWAY SCOPE in a cervical immobilization model, 5) tracheal intubation using AceScope in a normal airway model, and 6) tracheal intubation using AceScope in a fixed cervical spine model.In the normal airway model, significant differences were observed between McGrath MAC and AIRWAY SCOPE (p \u0026lt; 0.05) and AIRWAY SCOPE and AceScope (p \u0026lt; 0.05), but not between McGrath MAC and AceScope (p \u0026gt; 0.05). In the cervical spine immobilization model, significant differences in intubation time were found among all three groups (McGrath MAC vs. AIRWAY SCOPE: p \u0026lt; 0.05, McGrath MAC vs. AceScope: p \u0026lt; 0.05, AIRWAY SCOPE vs. AceScope: p \u0026lt; 0.05).\u003c/p\u003e","description":"","filename":"Figure2intubationtime12.png","url":"https://assets-eu.researchsquare.com/files/rs-4684340/v1/71cad1bb48203e5c773b1b86.png"},{"id":62153875,"identity":"73b93841-c7c5-43a5-a0e8-c118889e1dba","added_by":"auto","created_at":"2024-08-09 20:55:03","extension":"png","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":19588,"visible":true,"origin":"","legend":"\u003cp\u003ethe box-and-whisker plots delineating the perceived ease of use for the McGrath MAC, AIRWAY SCOPE, AceScope video laryngoscopes, as assessed by 60 participants employing a Visual Analog Scale (VAS). Upon completion of all six scenarios, the participants evaluated the facility of tracheal intubation for each of the three devices utilizing a VAS, where a score of 0 signified \"extremely easy\" and 10 indicated \"highly challenging\". The comparative analysis revealed no statistically significant differences among the three devices concerning their ease of use. McGrath MAC: Median VAS score = 6 (IQR: 4 - 8), AIRWAY SCOPE: Median VAS score = 7 (IQR: 5 - 9), AceScope: Median VAS score = 6 (IQR: 4 - 8)\u003c/p\u003e","description":"","filename":"Figure3videolaryngoscopesVAS91.png","url":"https://assets-eu.researchsquare.com/files/rs-4684340/v1/a7b4f26e1b00468b18fda82c.png"},{"id":81569811,"identity":"4286bbd3-9eaa-47d1-891c-35780ea2e415","added_by":"auto","created_at":"2025-04-28 16:11:29","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":2725541,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-4684340/v1/643d1e09-6ae8-43f8-92e3-64407a2dbc6b.pdf"},{"id":62153873,"identity":"6cf3655d-af3f-450c-888e-f9c8d4ec2430","added_by":"auto","created_at":"2024-08-09 20:55:03","extension":"xlsx","order_by":5,"title":"","display":"","copyAsset":false,"role":"supplement","size":579497,"visible":true,"origin":"","legend":"","description":"","filename":"file.xlsx","url":"https://assets-eu.researchsquare.com/files/rs-4684340/v1/839699fed0da5af9d2cddddc.xlsx"}],"financialInterests":"No competing interests reported.","formattedTitle":"\u003cp\u003eA Comparison of McGrath MAC, AIRWAY SCOPE®, and AceScope® Video laryngoscopes in Novice Healthcare Providers: A Randomized Crossover Simulation Study\u003c/p\u003e","fulltext":[{"header":"Introduction","content":"\u003cp\u003eVideo laryngoscopes have revolutionized tracheal intubation by offering enhanced visualization of the airway, particularly in challenging airway scenarios. The McGrath MAC (Aircraft Medical Ltd, Scotland, United Kingdom) and AIRWAY SCOPE\u0026reg; (Pentax Corporation, Tokyo, Japan) are two widely employed video laryngoscopes that have demonstrated efficacy in tracheal intubation across diverse clinical situations.\u003csup\u003e1, 2, 3\u003c/sup\u003e The AceScope\u0026reg; (IMI Co., Ltd., Seoul, Korea), a novel video laryngoscope, combines the McGrath MAC's optimal glottic visualization with the AIRWAY SCOPE's disposable blade and guide rail system, offering a sleek, lightweight design that promotes ease of use and maneuverability.\u003csup\u003e4\u003c/sup\u003e Despite its innovative design, there is limited clinical evidence comparing the effectiveness and usability of the AceScope with other prevalent video laryngoscopes.\u003csup\u003e5, 6\u003c/sup\u003e\u003c/p\u003e \u003cp\u003eThe primary objective of this study is to evaluate and compare the performance of the AceScope, McGrath MAC, and AIRWAY SCOPE in terms of intubation success rate and time to intubation during simulated tracheal intubation scenarios in novice healthcare providers using a manikin. Additionally, the study aims to assess user preferences and device ease of use as secondary outcomes in both simulated normal and difficult airway situations. This comparative analysis will help determine whether the AceScope provides any distinct advantages over the other two video laryngoscopes, thereby contributing to the optimization of airway management strategies.\u003c/p\u003e"},{"header":"Materials and Methods","content":"\u003cp\u003eAfter obtaining approval from the Ethics Committee of Hitachi General Hospital (Approval No. 2023-22, Clinical Research Registry No. UMIN000050394), written informed consent was secured from 60 nurses and pharmacists lacking prior tracheal intubation experience to participate in this randomized crossover study. The novices received verbal and demonstrative instruction from a board-certified anesthesiologist in Japan on the utilization of three types of video laryngoscopes (McGrath MAC, AIRWAY SCOPE, and AceScope). A malleable stylet was inserted into the endotracheal tube (ETT) and bent into a \"field hockey stick\" shape for intubation with the McGrath MAC.\u003csup\u003e7,8\u003c/sup\u003e In this study, two types of airway management simulators, the Laerdal Airway Management Trainer (Laerdal Medical, Stavanger, Norway), were prepared: a \"normal airway model\" that allowed subjects to freely and arbitrarily adjust the simulator's inherent head extension angle, and a \"Cervical Spine Immobilization Model,\" which was a custom-made difficult airway version created by the principal investigator.\u003csup\u003e9,10\u003c/sup\u003e The latter involved attaching a cervical spine protection collar for adults to the neck of the airway management simulator, rendering head extension impossible. Subsequently, participants were provided with five minutes of free training time for each device. Those who could not successfully intubate the trachea using at least one of the three video laryngoscopes were excluded from the study. A random order of the following six intubation scenarios was generated using a random number generator (\u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://www.random.org\u003c/span\u003e\u003cspan address=\"https://www.random.org\" targettype=\"URL\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e) by a physician distinct from the one who demonstrated tracheal intubation: 1) intubation with McGrath MAC in a normal airway model, 2) intubation with McGrath MAC in a cervical immobilization model, 3) intubation with AIRWAY SCOPE in a normal airway model, 4) intubation with AIRWAY SCOPE in a cervical immobilization model, 5) tracheal intubation using AceScope in a normal airway model, and 6) tracheal intubation using AceScope in a fixed cervical spine model. During the tracheal intubation scenarios, participants were permitted to request assistance from an assistant anesthesiologist at their discretion, starting 30 seconds after initiating the procedure.\u003csup\u003e11\u003c/sup\u003e The assistant could help with reinserting the laryngoscope, holding and supporting the laryngoscope, and adjusting the head position, and the number of instances in which the assistant provided aid was recorded. However, assistants were not allowed to touch the ETT. Upon completing all six scenarios, participants rated the ease of tracheal intubation for each device on a visual analog scale, with 0 signifying \"extremely easy\" and 10 denoting \"extremely difficult.\"\u003c/p\u003e \u003cp\u003eThe primary endpoint in this study was the duration of successful tracheal intubation. Intubation time was defined as the interval from the blade's entry between the teeth until the ETT was connected to the bag-valve mask and the model lung inflated.\u003csup\u003e9, 12\u003c/sup\u003e All intubation procedures were video-recorded. The position of the ETT tip was verified by the principal investigator following each intubation. Failure of intubation was defined as a time delay exceeding 120 seconds or inflation of the model stomach without inflating the model lung when utilizing the bag-valve mask. Secondary endpoints included the frequency of assistance required for successful intubation and the incidence of dental injuries (audible maxillary teeth clicking sounds).\u003csup\u003e13\u003c/sup\u003e\u003c/p\u003e \u003cp\u003eSample size calculations for this study were based on previous research comparing video laryngoscopes.\u003csup\u003e9, 12, 14\u003c/sup\u003e Assuming an average intubation time of 40 seconds with a standard deviation of 10 seconds, a sample size of 7 participants per group was determined to be necessary for detecting a minimum difference of 10 seconds in intubation time between groups, with a statistical power of 0.80 and an alpha level of 0.05. To account for potential dropouts and ensure an adequate sample size for each of the three devices, the study aimed to enroll 60 novice healthcare providers, comprising both nurses and pharmacists.\u003c/p\u003e \u003cdiv id=\"Sec3\" class=\"Section2\"\u003e \u003ch2\u003eStatistical Analysis:\u003c/h2\u003e \u003cp\u003eStatistical analyses were conducted using Stata version 17.1 (StataCorp, College Station, TX, USA). Data normality was assessed using the Shapiro-Wilk test. As intubation time data were normally distributed, they were presented as means\u0026thinsp;\u0026plusmn;\u0026thinsp;standard deviations. Differences in intubation time among devices were analyzed using repeated measures analysis of variance (ANOVA), followed by post-hoc tests with Bonferroni correction. Primary outcome measures included intubation times for each device in every scenario. Secondary outcome measures encompassed user preferences and ease of use for each device based on visual analog scale scores, the incidence of dental injuries, and the frequency of assistance required during intubation procedures. These outcomes were analyzed using descriptive statistics, such as means and standard deviations for continuous variables and proportions for categorical variables. The statistical significance of differences in outcomes among devices was determined using ANOVA or chi-square tests, as appropriate. Post-hoc comparisons were performed using Bonferroni-corrected pairwise comparisons, with a significance level set at p\u0026thinsp;\u0026lt;\u0026thinsp;0.05. All statistical tests were two-tailed.\u003c/p\u003e \u003c/div\u003e"},{"header":"Results","content":"\u003cp\u003eThe study involved 60 healthcare professionals with a median age of 32 years (interquartile range: 26 - 42 years), consisting of 35% males and 65% females, and including 71.7% nurses and 28.3% pharmacists. The objective was to compare intubation times using McGrath MAC, AIRWAY SCOPE, and AceScope video laryngoscopes in both normal airway and cervical spine immobilization models. Novice operators performed tracheal intubation with each device, and a repeated measures ANOVA was conducted on the intubation times for the three groups among 55 participants. Prior to the study, all fifty-five participants successfully completed tracheal intubation in all six scenarios after receiving a 5-minute demonstration and 15 minutes of hands-on training (5 minutes per device). Five participants were excluded due to difficulties handling the devices in the cervical spine immobilization model: three were unable to independently perform tracheal intubation using AceScope, and two were unable to independently perform tracheal intubation using McGrath MAC.\u003c/p\u003e\n\u003cp\u003eIn the normal airway model, the analysis revealed a significant effect of the device on intubation time (F(2, 54) = 8.358, p = 0.0002). The mean intubation times (SD) for the McGrath MAC, AIRWAY SCOPE, and AceScope groups were 18.67 (1.44), 14.90 (1.76), and 24.16 (2.49) seconds, respectively. Post-hoc comparisons using the Bonferroni correction demonstrated significant differences in intubation time between the McGrath MAC and AIRWAY SCOPE groups (p \u0026lt; 0.05), and between the AIRWAY SCOPE and AceScope groups (p \u0026lt; 0.05), but not between the McGrath MAC and AceScope groups (p \u0026gt; 0.05). In the cervical spine immobilization model, the repeated measures ANOVA indicated a significant effect of the device on intubation time (F(2, 57) = 7.04, p = 0.0007). The mean intubation times (SD) for the McGrath MAC, AIRWAY SCOPE, and AceScope groups were 26.33 (2.06), 23.80 (2.43), and 33.38 (2.50) seconds, respectively, with significant differences in intubation time among all three groups (McGrath MAC vs. AIRWAY SCOPE: p \u0026lt; 0.05, McGrath MAC vs. AceScope: p \u0026lt; 0.05, AIRWAY SCOPE vs. AceScope: p \u0026lt; 0.05) (Figure 2).\u003c/p\u003e\n\u003cp\u003eTable 1 presents the outcomes of the study, examining the success rates for intubation, the necessity for intubation assistance, and the incidence of dental injuries (quantified by the number of clicks) for each scenario. McGrath MAC, AIRWAY SCOPE and AceScope video laryngoscopes were all employed with both normal and cervical spine immobilization models in this study. In scenario 4, a single case of esophageal intubation occurred, while in scenario 6, there were two instances of esophageal intubation and time up.\u003c/p\u003e\n\u003cp\u003eParticipants assessed the difficulty of tracheal intubation using each device on a visual analog scale (VAS), and no significant differences in VAS ratings were observed among the devices (Figure 3). No significant differences in dental injury incidence were found among the McGrath MAC, AIRWAY SCOPE and AceScope in both normal and cervical spine immobilization models, except for a notable difference in dental injury rate between the AceScope and McGrath MAC in scenario 6 (23.6%, p = 0.04) (Table 1).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTable 1:\u0026nbsp;\u003c/strong\u003eOutcomes of a Study Investigating Endotracheal Intubation Scenarios Utilizing Various Videolaryngoscopes.\u003c/p\u003e\n\u003ctable border=\"0\" cellspacing=\"0\" cellpadding=\"0\" width=\"100%\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd width=\"22.448979591836736%\" rowspan=\"2\" valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003eScenario\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"16.3265306122449%\" rowspan=\"2\" valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003eFailed / Success\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e(Success rate)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"33.673469387755105%\" rowspan=\"2\" valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003eIntubation Assistance Required\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"27.551020408163264%\" colspan=\"4\" valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003eDental Injuries (number of clicks)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"25%\" valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003eNo injury\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"25%\" valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003e1\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"25%\" valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003e2\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"25%\" valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003e3\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"23.157894736842106%\" valign=\"top\"\u003e\n \u003cp\u003e1 (McGrath MAC normal)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"16.842105263157894%\" valign=\"top\"\u003e\n \u003cp\u003e0 / 55\u003c/p\u003e\n \u003cp\u003e(100%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"34.73684210526316%\" valign=\"top\"\u003e\n \u003cp\u003e3 (device hold)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"6.315789473684211%\" valign=\"top\"\u003e\n \u003cp\u003e60\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"6.315789473684211%\" valign=\"top\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"6.315789473684211%\" valign=\"top\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"6.315789473684211%\" valign=\"top\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"23.157894736842106%\" valign=\"top\"\u003e\n \u003cp\u003e2 (McGrath MAC difficult)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"16.842105263157894%\" valign=\"top\"\u003e\n \u003cp\u003e0 / 55\u003c/p\u003e\n \u003cp\u003e(100%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"34.73684210526316%\" valign=\"top\"\u003e\n \u003cp\u003e7 (device hold)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"6.315789473684211%\" valign=\"top\"\u003e\n \u003cp\u003e53\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"6.315789473684211%\" valign=\"top\"\u003e\n \u003cp\u003e4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"6.315789473684211%\" valign=\"top\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"6.315789473684211%\" valign=\"top\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"23.157894736842106%\" valign=\"top\"\u003e\n \u003cp\u003e3 (AIRWAY SCOPE normal)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"16.842105263157894%\" valign=\"top\"\u003e\n \u003cp\u003e0 / 55\u003c/p\u003e\n \u003cp\u003e(100%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"34.73684210526316%\" valign=\"top\"\u003e\n \u003cp\u003e2 (one head support, one device hold)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"6.315789473684211%\" valign=\"top\"\u003e\n \u003cp\u003e59\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"6.315789473684211%\" valign=\"top\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"6.315789473684211%\" valign=\"top\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"6.315789473684211%\" valign=\"top\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"23.157894736842106%\" valign=\"top\"\u003e\n \u003cp\u003e4 (AIRWAY SCOPE difficult)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"16.842105263157894%\" valign=\"top\"\u003e\n \u003cp\u003e1\u003csup\u003e\u0026dagger;\u003c/sup\u003e / 54\u003c/p\u003e\n \u003cp\u003e(98.2%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"34.73684210526316%\" valign=\"top\"\u003e\n \u003cp\u003e12 (six device hold, six device repositioning)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"6.315789473684211%\" valign=\"top\"\u003e\n \u003cp\u003e51\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"6.315789473684211%\" valign=\"top\"\u003e\n \u003cp\u003e4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"6.315789473684211%\" valign=\"top\"\u003e\n \u003cp\u003e4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"6.315789473684211%\" valign=\"top\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"23.157894736842106%\" valign=\"top\"\u003e\n \u003cp\u003e5 (AceScope normal)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"16.842105263157894%\" valign=\"top\"\u003e\n \u003cp\u003e0 / 55\u003c/p\u003e\n \u003cp\u003e(100%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"34.73684210526316%\" valign=\"top\"\u003e\n \u003cp\u003e10 (five head repositioning, four device hold, one device repositioning)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"6.315789473684211%\" valign=\"top\"\u003e\n \u003cp\u003e57\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"6.315789473684211%\" valign=\"top\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"6.315789473684211%\" valign=\"top\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"6.315789473684211%\" valign=\"top\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"23.157894736842106%\" valign=\"top\"\u003e\n \u003cp\u003e6 (AceScope difficult)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"16.842105263157894%\" valign=\"top\"\u003e\n \u003cp\u003e2\u003csup\u003e\u0026dagger;\u0026nbsp;\u003c/sup\u003e/ 53\u003c/p\u003e\n \u003cp\u003e(96.3%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"34.73684210526316%\" valign=\"top\"\u003e\n \u003cp\u003e18 (sixteen device hold, two device repositioning)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"6.315789473684211%\" valign=\"top\"\u003e\n \u003cp\u003e47*\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"6.315789473684211%\" valign=\"top\"\u003e\n \u003cp\u003e4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"6.315789473684211%\" valign=\"top\"\u003e\n \u003cp\u003e6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"6.315789473684211%\" valign=\"top\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003eTable 1 presents the outcomes of a study examining six distinct endotracheal intubation scenarios employing various videolaryngoscope devices. The success rates for intubation, the necessity for intubation assistance, and the incidence of dental injuries (quantified by the number of clicks) were documented. The McGrath MAC, AIRWAY SCOPE, and AceScope devices were all employed with both normal and cervical spine immobilization models in this study. In scenario 4, a single case of esophageal intubation occurred, while in scenario 6, there were two instances of esophageal intubation and time up. Abbreviations:\u0026dagger;, esophageal intubation or time up; *, significant difference in dental injury rate between AceScope and McGrath MAC (p = 0.04).\u003c/p\u003e"},{"header":"Discussion","content":"\u003cp\u003eThis study aimed to compare the effectiveness and usability of McGrath MAC, AIRWAY SCOPE, and AceScope video laryngoscopes during simulated tracheal intubation scenarios in novice healthcare providers. Our results demonstrated significant differences in intubation times among the three devices in both normal and cervical spine immobilization models. In the normal airway model, the AIRWAY SCOPE had the shortest intubation time, followed by the McGrath MAC and AceScope. In the cervical spine immobilization model, intubation times were significantly longer, with the AIRWAY SCOPE remaining the fastest, followed by the McGrath MAC and AceScope.\u003c/p\u003e \u003cp\u003eThese findings suggest that the AIRWAY SCOPE may be more efficient than the other two devices, particularly in challenging airway situations. This could be attributed to the AIRWAY SCOPE's unique design, which features a disposable blade and guide rail system that facilitates smooth endotracheal tube insertion.\u003csup\u003e15, 16\u003c/sup\u003e Previous studies have also reported the AIRWAY SCOPE's superiority in terms of intubation time compared to other video laryngoscopes.\u003csup\u003e17, 18, 19, 20\u003c/sup\u003e However, it is crucial to consider that the differences in intubation times might not be clinically significant, as all devices demonstrated a high success rate in both normal and difficult airway models.\u003c/p\u003e \u003cp\u003eIn terms of secondary outcomes, our study found that novice users reported similar levels of difficulty using three different video laryngoscopes based on their assessments using a visual analog scale (VAS). However, it should be noted that healthcare providers with varying levels of experience may have different experiences with these devices. Notably, the AceScope's user-friendly design may make it easier to use, underscoring the importance of appropriate training and practical experience in increasing healthcare providers' confidence and comfort when using these devices.\u003csup\u003e21, 22\u003c/sup\u003e\u003c/p\u003e \u003cp\u003eThe incidence of dental injuries was comparable among the McGrath MAC, AIRWAY SCOPE, and AceScope in both normal airway and cervical spine immobilization models, with the exception of a significant difference between the AceScope and McGrath MAC in scenario 6. It is important to note that dental injuries during tracheal intubation are a significant concern, as they can lead to patient discomfort, complications, and potential medicolegal issues.\u003csup\u003e23, 24\u003c/sup\u003e While the differences in dental injury rates observed in this study were minimal, further investigation into the factors contributing to these discrepancies may help identify strategies to reduce dental injury risk during intubation.\u003csup\u003e25\u003c/sup\u003e\u003c/p\u003e \u003cp\u003eThe AceScope is a novel video laryngoscope that combines the most advantageous features of the McGrath MAC and AIRWAY SCOPE, providing a lightweight design that facilitates ease of use and maneuverability.\u003csup\u003e4\u003c/sup\u003e Although the AceScope demonstrated longer intubation times in both normal and cervical spine immobilization models compared to the other devices, it is crucial to consider that the differences may not be clinically significant, given that all devices achieved high success rates (Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e2\u003c/span\u003e). The AceScope's blade shape is similar to that of the McGrath MAC, and its guide rail system is reminiscent of the unique feature of the AIRWAY SCOPE. These design features may potentially facilitate smooth endotracheal tube insertion and optimal glottic visualization. However, additional investigation is necessary to assess the effects of these characteristics on intubation outcomes. It is worth noting that the AceScope's longer intubation times may result from its unique design, which may require novices to adjust to a new technique, leading to longer intubation times. Subsequent studies should evaluate the effectiveness of the AceScope among providers with varying levels of experience to determine whether it offers any distinct advantages over the other two video laryngoscopes. Overall, the AceScope's innovative design warrants further investigation to determine its potential role in airway management strategies.\u003c/p\u003e \u003cp\u003eThis study has some limitations that should be acknowledged. Firstly, the use of a manikin model may not fully represent the complexities and challenges of intubating human subjects, particularly in difficult airway scenarios.\u003csup\u003e9, 12, 14, 17, 20, 25\u003c/sup\u003e Therefore, the generalizability of our findings to clinical practice should be approached cautiously. Secondly, the study only involved novice healthcare providers, and the results may not be applicable to experienced providers.\u003csup\u003e9, 26, 27\u003c/sup\u003e Future studies should examine the performance of these devices among providers with varying levels of experience to determine their effectiveness across a broader spectrum of healthcare professionals.\u003c/p\u003e \u003cp\u003eIn conclusion, our findings demonstrate that the AIRWAY SCOPE was the most efficient video laryngoscope in terms of intubation time, both in normal airway and cervical spine immobilization models, followed by the McGrath MAC and AceScope. However, all devices exhibited high success rates, and there were no significant differences in perceived difficulty among the three video laryngoscopes. Further research is needed to validate these findings in clinical settings and investigate the impact of device-specific features on intubation outcomes, as well as dental injury incidence.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eEthics approval and consent to participate\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThis study was approved by the Ethics Committee of Hitachi General Hospital (approval number 2023-22) and registered as a clinical trial with the registration number UMIN000050394. (https://center6.umin.ac.jp/cgi-open-bin/ctr/ctr_view.cgi?recptno=R000057382) The registration date of the clinical trial is February 21, 2023. Informed consent was obtained from all individual participants included in the study.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConsent for publication\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eWritten consent for publication was obtained from all individual participants included in the study.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAvailability of data and materials\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eAll data generated or analysed during this study are included in this published article and its supplementary information files.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eCompeting interests\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe authors declare that they have no competing interests.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFunding\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eSupport was provided solely from institutional and departmental sources.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAuthors' contributions\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eY.Y. and M.Y. designed the study. Y.Y. and K.O. performed the data collection and analysis. M.Y. wrote the manuscript draft. Both authors reviewed and approved the final manuscript.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAcknowledgements\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe authors would like to express their gratitude to Professor Makoto Tanaka (M.D. Dean, College of Medicine, School of Health Sciences Professor and Chairman Department of Anesthesiology Institute of Clinical Medicine, University of Tsukuba, Tsukuba-city, Ibaraki, JAPAN) for his valuable guidance and support.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eChen YY, Lin JC, Tsai MJ, Cheng KY. Retromolar intubation with video intubating stylet in difficult airway: A randomized crossover manikin study. Am J Emerg Med. 2022 Apr;54:212-220. doi: 10.1016/j.ajem.2022.02.008. Epub 2022 Feb 9. 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A comparison of McGrath MAC\u0026reg; and standard direct laryngoscopy in simulated immobilized cervical spine pediatric intubation: a manikin study. Eur J Pediatr. 2017 Jun;176(6):779-786. doi: 10.1007/s00431-017-2909-9. Epub 2017 Apr 21. PMID: 28429117; PMCID: PMC5432598.\u003c/li\u003e\n\u003cli\u003eKleine-Brueggeney M, Greif R, Schoettker P, Savoldelli GL, Nabecker S, Theiler LG. Evaluation of six videolaryngoscopes in 720 patients with a simulated difficult airway: a multicentre randomized controlled trial. Br J Anaesth. 2016 May;116(5):670-9. doi: 10.1093/bja/aew058. PMID: 27106971.\u003c/li\u003e\n\u003cli\u003eAoi Y, Inagawa G, Nakamura K, Sato H, Kariya T, Goto T. Airway scope versus macintosh laryngoscope in patients with simulated limitation of neck movements. J Trauma. 2010 Oct;69(4):838-42. doi: 10.1097/TA.0b013e3181c4529e. PMID: 20179653.\u003c/li\u003e\n\u003cli\u003eMurakami Y, Ueki R, Niki M, Hirose M, Shimode N. Three-day tracheal intubation manikin training for novice doctors using Macintosh laryngoscope, McGRATH MAC videolaryngoscope and Pentax AirwayScope. Medicine (Baltimore). 2021 Jan 29;100(4): e23886. doi: 10.1097/MD.0000000000023886. PMID: 33530183; PMCID: PMC7850776.\u003c/li\u003e\n\u003cli\u003eMalik MA, Maharaj CH, Harte BH, Laffey JG. Comparison of Macintosh, Truview EVO2, Glidescope, and Airwayscope laryngoscope use in patients with cervical spine immobilization. Br J Anaesth. 2008 Nov;101(5):723-30. doi: 10.1093/bja/aen231. Epub 2008 Sep 9. PMID: 18784069.\u003c/li\u003e\n\u003cli\u003eTeoh WH, Shah MK, Sia AT. Randomised comparison of Pentax AirwayScope and Glidescope for tracheal intubation in patients with normal airway anatomy. Anaesthesia. 2009 Oct;64(10):1125-9. doi: 10.1111/j.1365-2044.2009.06032. x. PMID: 19735405.\u003c/li\u003e\n\u003cli\u003eTan Y, Loganathan N, Thinn KK, Liu EHC, Loh NW. Dental injury in anaesthesia: a tertiary hospital\u0026apos;s experience. BMC Anesthesiol. 2018 Aug 16;18(1):108. doi: 10.1186/s12871-018-0569-6. PMID: 30111288; PMCID: PMC6094905.\u003c/li\u003e\n\u003cli\u003eWarner ME, Benenfeld SM, Warner MA, Schroeder DR, Maxson PM. Perianesthetic dental injuries: frequency, outcomes, and risk factors. Anesthesiology. 1999 May;90(5):1302-5. doi: 10.1097/00000542-199905000-00013. PMID: 10319777.\u003c/li\u003e\n\u003cli\u003eCarassiti M, Zanzonico R, Cecchini S, Silvestri S, Cataldo R, Agr\u0026ograve; FE. Force and pressure distribution using Macintosh and GlideScope laryngoscopes in normal and difficult airways: a manikin study. Br J Anaesth. 2012 Jan;108(1):146-51. doi: 10.1093/bja/aer304. Epub 2011 Sep 28. PMID: 21965048.\u003c/li\u003e\n\u003cli\u003eKleine-Brueggeney M, Buttenberg M, Greif R, Nabecker S, Theiler L. Evaluation of three unchannelled videolaryngoscopes and the Macintosh laryngoscope in patients with a simulated difficult airway: a randomised, controlled trial. 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PMID: 27882535.\u003c/li\u003e\n\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":true,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"bmc-anesthesiology","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"bane","sideBox":"Learn more about [BMC Anesthesiology](http://bmcanesthesiol.biomedcentral.com/)","snPcode":"","submissionUrl":"https://www.editorialmanager.com/bane","title":"BMC Anesthesiology","twitterHandle":"BMC_series","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"em","reportingPortfolio":"BMC Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true},"keywords":"","lastPublishedDoi":"10.21203/rs.3.rs-4684340/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-4684340/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003ch2\u003eBackground\u003c/h2\u003e \u003cp\u003eVideo laryngoscopes are widely used for tracheal intubation, particularly in challenging airway scenarios. The McGrath MAC, AIRWAY SCOPE\u0026reg;, and AceScope\u0026reg; 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.\u003c/p\u003e\u003ch2\u003eMethods\u003c/h2\u003e \u003cp\u003eSixty 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.\u003c/p\u003e\u003ch2\u003eResults\u003c/h2\u003e \u003cp\u003eThe AIRWAY SCOPE demonstrated the shortest intubation time in both normal airway and cervical spine immobilization models (14.90\u0026thinsp;\u0026plusmn;\u0026thinsp;1.76 seconds and 23.80\u0026thinsp;\u0026plusmn;\u0026thinsp;2.43 seconds, 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 comparable among the devices, with one notable exception between the AceScope and McGrath MAC in scenario of tracheal intubation using AceScope in a cervical spine immobilization model.\u003c/p\u003e\u003ch2\u003eConclusions\u003c/h2\u003e \u003cp\u003eThe 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.\u003c/p\u003e","manuscriptTitle":"A Comparison of McGrath MAC, AIRWAY SCOPE®, and AceScope® Video laryngoscopes in Novice Healthcare Providers: A Randomized Crossover Simulation Study","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2024-08-09 20:54:58","doi":"10.21203/rs.3.rs-4684340/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Revision requested","date":"2024-11-13T07:57:30+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2024-07-09T10:57:58+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2024-07-09T10:57:20+00:00","index":"","fulltext":""},{"type":"submitted","content":"BMC Anesthesiology","date":"2024-07-04T06:53:30+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"bmc-anesthesiology","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"bane","sideBox":"Learn more about [BMC Anesthesiology](http://bmcanesthesiol.biomedcentral.com/)","snPcode":"","submissionUrl":"https://www.editorialmanager.com/bane","title":"BMC Anesthesiology","twitterHandle":"BMC_series","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"em","reportingPortfolio":"BMC Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"12aa9d51-7497-4dbe-8ca3-4775da7b05c1","owner":[],"postedDate":"August 9th, 2024","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"published-in-journal","subjectAreas":[],"tags":[],"updatedAt":"2025-04-28T16:04:13+00:00","versionOfRecord":{"articleIdentity":"rs-4684340","link":"https://doi.org/10.1186/s12871-025-03094-y","journal":{"identity":"bmc-anesthesiology","isVorOnly":false,"title":"BMC Anesthesiology"},"publishedOn":"2025-04-25 15:58:22","publishedOnDateReadable":"April 25th, 2025"},"versionCreatedAt":"2024-08-09 20:54:58","video":"","vorDoi":"10.1186/s12871-025-03094-y","vorDoiUrl":"https://doi.org/10.1186/s12871-025-03094-y","workflowStages":[]},"version":"v1","identity":"rs-4684340","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-4684340","identity":"rs-4684340","version":["v1"]},"buildId":"qtupq5eGEP_6zYnWcrvyt","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}