McGrath videolaryngoscope versus Macintosh laryngoscope for tracheal intubation: A systematic review and meta-analysis with trial sequential analysis

Comparison of Macintosh Laryngoscope, King Vision®, VividTrac®, AirAngel Blade®, and a Custom-Made 3D-Printed Video Laryngoscope for Difficult and Normal Airways in Mannequins by Novices-A Non-Inferiority Trial

Background: Endotracheal intubation (ETI) is a cornerstone of airway management. The gold standard device for ETI is still the direct laryngoscope (DL). However, video laryngoscopes (VLs) are now also widely available and have several proven advantages. The VL technique has been included in the major airway management guidelines. During the COVID-19 pandemic, supply chain disruption has raised demand for 3D-printed medical equipment, including 3D-printed VLs. However, studies on performance are only sparsely available; thus, we aimed to compare 3D-printed VLs to the DL and other VLs made with conventional manufacturing technology. Methods: Forty-eight medical students were recruited to serve as novice users. Following brief, standardized training, students executed ETI with the DL, the King Vision® (KV), the VividTrac® (VT), the AirAngel Blade® (AAB), and a custom-made 3D-printed VL (3DVL) on the Laerdal® airway management trainer in normal and difficult airway scenarios. We evaluated the time to and proportion of successful intubation, the best view of the glottis, esophageal intubation, dental trauma, and user satisfaction. Results: The KV and VT are proved to be superior (p < 0.05) to the DL in both scenarios. The 3DVL's performance was similar (p > 0.05) or significantly better than that of the DL and mainly non-inferior (p > 0.05) compared to the KV and VT in both scenarios. Regardless of the scenario, the AAB proved to be inferior (p < 0.05) even to the DL in the majority of the variables. The differences between the devices were more pronounced in the difficult airway scenario. The user satisfaction scores were in concordance with the aforementioned performance of the scopes. Conclusions: Based upon our results, we cannot recommend the AAB over the DL, KV, or VT. However, as the 3DVL showed, 3D printing indeed can provide useful or even superior VLs, but prior to clinical use, meticulous evaluation might be recommended.

Spanish Society of Anesthesiology, Reanimation and Pain Therapy (SEDAR), Spanish Society of Emergency and Emergency Medicine (SEMES) and Spanish Society of Otolaryngology, Head and Neck Surgery (SEORL-CCC) Guideline for difficult airway management. Part II

The Airway Management section of the Spanish Society of Anesthesiology, Resuscitation, and Pain Therapy (SEDAR), the Spanish Society of Emergency Medicine (SEMES), and the Spanish Society of Otorhinolaryngology and Head and Neck Surgery (SEORL-CCC) present the Guide for the comprehensive management of difficult airway in adult patients. Its principles are focused on the human factors, cognitive processes for decision-making in critical situations, and optimization in the progression of strategies application to preserve adequate alveolar oxygenation in order to enhance safety and the quality of care. The document provides evidence-based recommendations, theoretical-educational tools, and implementation tools, mainly cognitive aids, applicable to airway management in the fields of anesthesiology, critical care, emergencies, and prehospital medicine. For this purpose, an extensive literature search was conducted following PRISMA-R guidelines and was analyzed using the GRADE methodology. Recommendations were formulated according to the GRADE methodology. Recommendations for sections with low-quality evidence were based on expert opinion through consensus reached via a Delphi questionnaire.

Comparison of Indirect and Direct Laryngoscopes in Pediatric Patients with a Difficult Airway: A Systematic Review and Meta-Analysis

This meta-analysis was performed to determine whether an indirect laryngoscope is more advantageous than a direct laryngoscope for tracheal intubation in the setting of a difficult pediatric airway. Data on the intubation failure and intubation time during tracheal intubation were extracted from prospective and retrospective studies identified through a comprehensive literature search. Data from 10 individual articles (11 trials) were combined, and a DerSimonian and Laird random-effects model was used to calculate either the pooled relative risk (RR) or the weighted mean difference (WMD) and the corresponding 95% confidence interval (CI). Meta-analysis of the 10 articles indicated that the intubation failure of tracheal intubation with an indirect laryngoscope was not significantly different from that of a direct laryngoscope in patients with a difficult airway (RR 0.86, 95% CI 0.51-1.46; p = 0.59; Cochrane's Q = 50.5; I2 = 82%). Intubation time with an indirect laryngoscope was also similar to that with a direct laryngoscope (WMD 4.06 s; 95% CI -1.18-9.30; p = 0.13; Cochrane's Q 39.8; I2 = 85%). In conclusion, indirect laryngoscopes had the same intubation failure and intubation time as direct laryngoscopes in pediatric patients with a difficult airway. Currently, the benefits of indirect laryngoscopes have not been observed in the setting of a difficult pediatric airway.

Comparison of McGrath Videolaryngoscope versus Macintosh Laryngoscope in Tracheal Intubation: An Updated Systematic Review

(1) Background: In the last few years, many randomized controlled trials (RCTs) have compared direct Macintosh laryngoscopy with McGrath videolaryngoscopy in order to assess the potential benefits of the latter; the results were sometimes controversial. (2) Methods: We conducted a comprehensive literature search to identify our articles according to inclusion and exclusion criteria: to be included, each study had to be a prospective randomized trial or comparison between the McGrath videolaryngoscope and the Macintosh laryngoscope in an adult population. We did not include manikin trials or studies involving double-lumen tubes. (3) Results: 10 studies met the inclusion criteria necessary. In total, 655 patients were intubated with the McGrath and 629 with the Macintosh. In total, 1268 of 1284 patients were successfully intubated, showing equivalent results for the two devices: 648 of 655 patients with the McGrath videolaryngoscope and 620 of 629 patients with the Macintosh laryngoscope. No differences were noted in terms of hemodynamic changes or the incidence of adverse events. (4) Conclusions: We can assert that the McGrath videolaryngoscope and Macintosh laryngoscope, even if with equivalent tracheal intubation results, supplement each other.

Awake Tracheal Intubation Is Associated with Fewer Adverse Events in Critical Care Patients than Anaesthetised Tracheal Intubation

BACKGROUND

Tracheal intubation in critical care is a high-risk procedure requiring significant expertise and airway strategy modification. We hypothesise that awake tracheal intubation is associated with a lower incidence of severe adverse events compared to standard tracheal intubation in critical care patients.

METHODS

Records were acquired for all tracheal intubations performed from 2020 to 2022 for critical care patients at a tertiary hospital. Each awake tracheal intubation case, using a videolaryngoscope with a hyperangulated blade (McGrath® MAC X-Blade), was propensity matched with two controls (1:2 ratio; standard intubation videolaryngoscopy (VL) and direct laryngoscopy (DL) undergoing general anaesthesia). The primary endpoint was the incidence of adverse events, defined as a mean arterial pressure of <55 mmHg (hypotension), SpO2 < 80% (desaturation) after sufficient preoxygenation, or peri-interventional cardiac arrest.

RESULTS

Of the 135 tracheal intubations included for analysis, 45 involved the use of an awake tracheal intubation. At least one adverse event occurred after tracheal intubation in 36/135 (27%) of patients, including awake 1/45 (2.2%; 1/1 hypotension), VL 10/45 (22%; 6/10 hypotension and 4/10 desaturation), and DL 25/45 (47%; 10/25 hypotension, 12/25 desaturation, and 3/25 cardiac arrest; p < 0.0001).

CONCLUSIONS

In this retrospective observational study of intubation practices in critical care patients, awake tracheal intubation was associated with a lower incidence of severe adverse events than anaesthetised tracheal intubation.

A multicentre randomised controlled trial of the McGrath Mac videolaryngoscope versus conventional laryngoscopy

Before completion of this study, there was insufficient evidence demonstrating the superiority of videolaryngoscopy compared with direct laryngoscopy for elective tracheal intubation. We hypothesised that using videolaryngoscopy for routine tracheal intubation would result in higher first-pass tracheal intubation success compared with direct laryngoscopy. In this multicentre randomised trial, 2092 adult patients without predicted difficult airway requiring tracheal intubation for elective surgery were allocated randomly to either videolaryngoscopy with a Macintosh blade (McGrath) or direct laryngoscopy. First-pass tracheal intubation success was higher with the McGrath (987/1053, 94%), compared with direct laryngoscopy (848/1039, 82%); absolute risk reduction (95%CI) was 12.1% (10.9-13.6%). This resulted in a relative risk (95%CI) of unsuccessful tracheal intubation at first attempt of 0.34 (0.26-0.45; p < 0.001) for McGrath compared with direct laryngoscopy. Cormack and Lehane grade ≥ 3 was observed more frequently with direct laryngoscopy (84/1039, 8%) compared with McGrath (8/1053, 0.7%; p < 0.001) No significant difference in tracheal intubation-associated adverse events was observed between groups. This study demonstrates that using McGrath videolaryngoscopy compared with direct laryngoscopy improves first-pass tracheal intubation success in patients having elective surgery. Practitioners may consider using this device as first choice for tracheal intubation.

Successful Tracheal Intubation With Airway Scope After Failure With McGrath

The use of video laryngoscopy is growing in patients with anatomical factors suggestive of a difficult airway. This case report describes the successful tracheal intubation of a 54-year-old female patient with limited mouth opening scheduled for third molar extraction under general anesthesia. The Airway scope (AWS) along with a gum-elastic bougie was used to secure the airway after failed direct laryngoscopy and video laryngoscopy using the McGrath MAC with an X-blade. The AWS has a J-shaped structure in which the blade approximates the curvature of the pharynx and larynx. This blade shape makes it easy to match the laryngeal axis with the visual field direction, enabling successful tracheal intubation even for patients with limited mouth opening. A major key to successful video laryngoscopy is to select a video laryngoscope based on the anatomical characteristics of patients with a difficult airway.

Comparison of the McGRATHTM Video Laryngoscope and Macintosh Laryngoscope for Orotracheal Intubation in a Simulated Difficult Airway Scenario: An Open-Label, Randomized Clinical Trial

Background and Objectives: Difficult intubation, which may be encountered unexpectedly during anesthesia, can increase patients' morbidity and mortality. The McGRATH video laryngoscope is known to provide improved laryngeal visibility in patients with difficult or normal airways. The purpose of this study was to evaluate the efficacy of the McGRATH video laryngoscope for orotracheal intubation compared with that of conventional Macintosh laryngoscopes in simulated difficult airway scenarios. Materials and Methods: In this randomized controlled trial, patients who were scheduled for surgery under general anesthesia requiring orotracheal intubation were assigned to the Macintosh laryngoscope (n = 50) or McGRATH video laryngoscope (n = 45) groups. In this study, to create a simulated difficult airway condition, the subjects performed manual in-line stabilization and applied a soft cervical collar. The primary outcome was the rate of successful intubation within 30 s. The time required for an intubation, glottis grade, intubation difficulty scale (IDS score), the subjective ease of intubation, and optimal external laryngeal manipulation (OLEM) were evaluated. In addition, complications caused by each blade were investigated. Results: The intubation success rate within 30 s was not significantly different between the two groups (44 (88.0%) vs. 36 (80.0%), p = 0.286). The glottic grade was better in the McGRATH group than in the Macintosh group (p = 0.029), but neither the intubation time (26.3 ± 8.2 s vs. 24.2 ± 5.0 s, p = 0.134) nor the rates of oral bleeding (2 (4.0%) vs. 0 (0.0%)) and tooth injury (0 (0.0%) vs. 1 (2.2%)) were significantly different between the two groups. Conclusions: The use of the McGRATH video laryngoscope did not improve the intubation success rate or shorten the intubation time. However, the McGRATH video laryngoscope provided a better glottis view than the conventional Macintosh laryngoscope in patients with a simulated difficult airway.

Effectiveness of Indirect and Direct Laryngoscopes in Pediatric Patients: A Systematic Review and Network Meta-Analysis

This research aimed to produce a coherent ranking of the effectiveness of intubation devices in pediatric patients using network meta-analysis (NMA). We searched the electric databases for prospective randomized studies that compared different tracheal intubation devices in pediatric patients. The primary outcome was intubation failure at the first attempt. Secondary outcomes were glottic visualization and intubation time. The statistical analysis performed used DerSimonian and Laird random-effects models. Frequentist network meta-analysis was conducted, and network plots and network league tables were produced. Subgroup analysis was performed after excluding rigid-fiberscope-type indirect laryngoscopes. Thirty-four trials comparing 13 devices were included. Most laryngoscopes had the same intubation failure rate as the Macintosh reference device. Only the Truview PCD™ had a significantly higher intubation failure rate than the Macintosh (odds ratio 4.78, 95% confidence interval 1.11–20.6) The highest-ranking laryngoscope was the Airtaq™ (P score, 0.90), and the AirwayScope™, McGrath™, and Truview EVO2™ ranked higher than the Macintosh. The Bullard™ had the lowest ranking (P score, 0.08). All laryngoscopes had the same level of glottic visualization as the Macintosh and only the C-MAC™ had a significantly shorter intubation time. Intubation time was significantly longer when using the GlideScope™, Storz DCI™, Truview PCD™, or Bullard™ compared with the Macintosh. P score and ranking of devices in the subgroup analyses were similar to those in the main analysis. We applied NMA to create a consistent ranking of the effectiveness of intubation devices in pediatric patients. The findings of NMA suggest that there is presently no laryngoscope superior to the Macintosh laryngoscope in terms of tracheal intubation failure rate and glottic visualization in pediatric patients.

Comparison of video-stylet and conventional laryngoscope for endotracheal intubation in adults with cervical spine immobilization: A PRISMA-compliant meta-analysis

BACKGROUND

Although minimization of cervical spine motion by using a neck collar or manual in-line stabilization is recommended for urgent tracheal intubation (TI) in patients with known or suspected cervical spine injury (CSI), it may worsen glottic visualization. The overall performance of video-stylets during TI in patients with neck immobilization remains unclear. The current meta-analysis aimed at comparing the intubation outcomes of different video-stylets with those of conventional laryngoscopes in patients with cervical immobilization.

METHOD

The databases of Embase, Medline, and the Cochrane Central Register of Controlled Trials were searched from inception to June 2021 to identify trials comparing intubation outcomes between video-stylets and conventional laryngoscopes. The primary outcome was first-pass success rate, while secondary outcomes included overall success rate, time to intubation, the risk of intubation-associated sore throat, or tissue damage.

RESULTS

Five randomized controlled trials published between 2007 and 2013 involving 487 participants, all in an operating room setting, were analyzed. The video-stylets investigated included Bonfils intubation fiberscope, Levitan FPS Scope, and Shikani optical stylet. There was no difference in first-pass success rate (risk ratio [RR] =1.08, 95% confidence interval [CI]: 0.89-1.31, P = .46], overall success rate (RR = 1.06, 95% CI: 0.93-1.22, P = .4), intubation time [mean difference = 4.53 seconds, 95% CI: -8.45 to 17.51, P = .49), and risk of tissue damage (RR = 0.46, 95% CI: 0.16-1.3, P = .14) between the 2 groups. The risk of sore throat was lower with video-stylets compared to that with laryngoscopes (RR = 0.45, 95% CI: 0.23-0.9, P = .02).

CONCLUSION

Our results did not support the use of video-stylets as the first choice for patients with neck immobilization. Further studies are required to verify the efficacy of video-stylets in the nonoperating room setting.

A Comparison of McGrath Videolaryngoscope versus Macintosh Laryngoscope for Nasotracheal Intubation: A Systematic Review and Meta-Analysis

Background: In this study, it was shown that the routine use of McGrath videolaryngoscopy may improve intubation success rates. The benefits to using a videolaryngoscope in nasotracheal intubation were also demonstrated. However, no solid evidence concerning the effectiveness of the use of McGrath videolaryngoscopes in nasotracheal intubation has previously been reported. As a result, we questioned whether, in adult patients who underwent oral and maxillofacial surgeries with nasotracheal intubation (P), the use of a McGrath videolaryngoscope (I) compared with a Macintosh laryngoscope (C) could reduce the intubation time, improve glottis visualization to a score of classification 1 in the Cormack–Lehane classification system, and improve the first-attempt success rate (O). The secondary outcomes measured were the rate of the use of Magill forceps and the external laryngeal pressure (BURP) maneuver used. Methods: An extensive literature search was conducted using databases. Only randomized controlled trials that compared the McGrath videolaryngoscopy and Macintosh laryngoscopy techniques in nasotracheal intubation in adult patients were included. Results: Five articles met the inclusion criteria and were included in the final analysis (n = 331 patients). The results showed a significant decrease in intubation time and a higher rate of classification 1 scores in the Cormack–Lehane classification system, but no difference in the first-attempt success rates were found between the McGrath group and the Macintosh group. Decreases in the rate of the use of Magill forceps and the use of the external laryngeal pressure maneuver were also found in the pooled analysis. With regard to the overall risk of bias, the selected trials were classified to have at least a moderate risk of bias, because none of the trials could blind the operator to the type of laryngoscope used. Conclusions: Our analysis suggests that the use of a McGrath videolaryngoscope in nasotracheal intubation resulted in shorter intubation times, improved views of the glottis and similar first-success rates in adult patients who received general anesthesia for dental, oral, maxillofacial, or head and neck cancer surgery, and also reduced the use of Magill forceps and the BURP maneuver.

Comparison of self-assembled video laryngoscope versus McGrath MAC®: A randomised controlled trial

Background and Aims:

Video laryngoscopy highly improves the success rate for endotracheal intubation. However, commercially available video laryngoscopes such as McGrath MAC^® can be costly. An economical video laryngoscope was assembled by attaching a fibreoptic videoscope into a Macintosh laryngoscope. This randomised study aimed to compare the intubation time of this self-assembled modified Macintosh video laryngoscope (SAM-VL) and McGrath MAC^® (McGrath).

Methods:

This study enroled 62 adults scheduled for elective surgery under general anaesthesia with endotracheal intubation. The primary outcome was total intubation time. Secondary outcomes were the time for glottic visualisation (time A), time for tube insertion after glottic visualisation (time B), first-attempt intubation success rate, degree of glottic visualisation, and need for backward, upward, rightward pressure (BURP) assistance, complications, and user satisfaction. The tests used were: Kolmogorov-Smirnov and the Mann-Whitney test to analyse the data’s distribution and the primary outcome, respectively.

Results:

The median total intubation time in the SAM-VL group versus the McGrath was 63 s (27–114s) versus 74 s (40–133s), respectively (P = 0.032). Intubation time B was significantly faster, while the score of glottic visualisation and BURP assistance was significantly higher in the SAM-VL group. The differences in the rate of successful first attempts and complications were not statistically significant. SAM-VL users rated the ease of blade insertion and manoeuvrability, degree of glottic visualisation, and overall rating as very high.

Conclusion:

Endotracheal intubation using self-assembled modified video laryngoscope is faster and allows better glottis visualisation than McGrath MAC^®.

Comparison of McGrath Videolaryngoscope and Macintosh Laryngoscope in Children with Torticollis: Randomized Controlled Trial

We investigated the efficacy of the McGrath videolaryngoscope compared with the Macintosh laryngoscope in children with torticollis. Thirty children aged 1–10 years who underwent surgical release of torticollis were randomly assigned into the McGrath and Macintosh groups. Orotracheal intubation was performed by a skilled anesthesiologist. The primary outcome was the intubation time. The Cormack–Lehane grade, lifting force, intubation difficulty scale (IDS), difficulty level, and intubation failure rate were also assessed. The intubation time was significantly longer in the McGrath group than in the Macintosh group (31.4 ± 6.7 s vs. 26.1 ± 5.4 s, p = 0.025). Additionally, the Cormack–Lehane grades were comparable between the groups (p = 0.101). The lifting force and IDS were significantly lower in the McGrath group than in the Macintosh group (p < 0.001 and p = 0.022, respectively). No significant differences were observed with respect to endotracheal intubation difficulty and intubation success rate. Intubation-related complications were also not observed. In conclusion, compared with the Macintosh laryngoscope, the McGrath videolaryngoscope extended the intubation time and did not improve glottic visualization in children with torticollis, despite having a lesser lifting force, lower intubation difficulty scale, and similar success rate.

Videolaryngoscopy vs. direct Macintosh laryngoscopy in tracheal intubation in adults: a ranking systematic review and network meta-analysis

Videolaryngoscopes are thought to improve glottic view and facilitate tracheal intubation compared with the Macintosh direct laryngoscope. However, we currently do not know which one would be the best choice in most patients undergoing anaesthesia. We designed this systematic review with network meta-analyses to rank the different videolaryngoscopes and the Macintosh direct laryngoscope. We conducted searches in PubMed and a further five databases on 11 January 2021. We included randomised clinical trials with patients aged ≥16 years, comparing different videolaryngoscopes, or videolaryngoscopes with the Macintosh direct laryngoscope for the outcomes: failed intubation; failed first intubation attempt; failed intubation within two attempts; difficult intubation; percentage of glottic opening seen; difficult laryngoscopy; and time needed for intubation. We assessed the quality of evidence according to GRADE recommendations and included 179 studies in the meta-analyses. The C-MAC and C-MAC D-Blade were top ranked for avoiding failed intubation, but we did not find statistically significant differences between any two distinct videolaryngoscopes for this outcome. Further, the C-MAC D-Blade performed significantly better than the C-MAC Macintosh blade for difficult laryngoscopy. We found statistically significant differences between the laryngoscopes for time to intubation, but these differences were not considered clinically relevant. The evidence was judged as of low or very low quality overall. In conclusion, different videolaryngoscopes have differential intubation performance and some may be currently preferred among the available devices. Furthermore, videolaryngoscopes and the Macintosh direct laryngoscope may be considered clinically equivalent for the time taken for tracheal intubation. However, despite the rankings from our analyses, the current available evidence is not sufficient to ensure significant superiority of one device or a small set of them over the others for our intubation-related outcomes.

Anaesthesia protocol evaluation of the videolaryngoscopy with the McGrath MAC and direct laryngoscopy for tracheal intubation in 1000 patients undergoing rapid sequence induction: the randomised multicentre LARA trial study protocol

INTRODUCTION

Rapid sequence induction of anaesthesia is indicated in patients with an increased risk of pulmonary aspiration. The main objective of the technique is to reduce the critical time period between loss of airway protective reflexes and rapid inflation of the cuff of the endotracheal tube to minimise the chance of aspiration of gastric contents. The COVID-19 pandemic has reinforced the importance of first-pass intubation success to ensure patient and healthcare worker safety. The aim of this study is to compare the first-pass intubation success rate (FPS) using the videolaryngoscopy compared with conventional direct laryngoscopy in surgical patients with a high risk of pulmonary aspiration.

METHODS AND ANALYSIS

The LARA trial is a multicentre, patient-blinded, randomised controlled trial. Consecutive patients requiring tracheal intubation are randomly allocated to either the McGrath MAC videolaryngoscope or direct laryngoscopy using the Macintosh laryngoscope. The expected rate of FPS is 92% in the McGrath group and 82% in the Macintosh group. Each group must include a total of 500 patients to achieve 90% power for detecting a difference at the 5% significance level. Successful intubation with the FPS is the primary endpoint. The secondary endpoints are the time to intubation, the number of intubation attempts, the necessity of airway management alternatives, the visualisation of the glottis using the Cormack and Lehane Score and the Percentage Of Glottic Opening Score and definite adverse events.

ETHICS AND DISSEMINATION

The project is approved by the local ethics committee of the Medical Association of the Rhineland Palatine state (registration number: 2020-15502) and medical ethics committee of the University of Freiburg (registration number: 21-1303). The results of this study will be made available in form of manuscripts for publication and presentations at national and international meetings.

TRIAL REGISTRATION

NCT04794764.

Impact of Videolaryngoscopy Expertise on First-Attempt Intubation Success in Critically Ill Patients

OBJECTIVES

The use of a videolaryngoscope in the ICU on the first endotracheal intubation attempt and intubation-related complications is controversial. The objective of this study was to evaluate the first intubation attempt success rate in the ICU with the McGrath MAC videolaryngoscope (Medtronic, Minneapolis, MN) according to the operators' videolaryngoscope expertise and to describe its association with the occurrence of intubation-related complications.

DESIGN

Observational study.

SETTING

Medical ICU.

SUBJECTS

Consecutive endotracheal intubations in critically ill patients.

INTERVENTIONS

Systematic use of the videolaryngoscope.

MEASUREMENTS AND MAIN OUTCOMES

We enrolled 202 consecutive endotracheal intubations. Overall first-attempt success rate was 126 of 202 (62%). Comorbidities, junior operator, cardiac arrest upon admission, and coma were associated with a lower first-attempt success rate. The first-attempt success rate was less than 50% in novice operators (1-5 previous experiences with videolaryngoscope, independently of airway expertise with direct laryngoscopies) and 87% in expert operators (> 15 previous experiences with videolaryngoscope). Multivariate analysis confirmed the association between specific skill training with videolaryngoscope and the first-attempt success rate. Severe hypoxemia and overall immediate intubation-related complications occurred more frequently in first-attempt failure intubations (24/76, 32%) than in first-attempt success intubations (14/126, 11%) (p < 0.001).

CONCLUSIONS

We report for the first time in the critically ill that specific videolaryngoscopy skill training, assessed by the number of previous videolaryngoscopies performed, is an independent factor of first-attempt intubation success. Furthermore, we observed that specific skill training with the McGrath MAC videolaryngoscope was fast. Therefore, future trials evaluating videolaryngoscopy in ICUs should consider the specific skill training of operators in videolaryngoscopy.

A systematic review of meta-analyses comparing direct laryngoscopy with videolaryngoscopy

PURPOSE

In the preceding 20 years, many randomized-controlled trials and meta-analyses have compared direct Macintosh laryngoscopy with videolaryngoscopy. The videolaryngoscope blades have included both traditional Macintosh blades and hyperangulated blades. Macintosh and hyperangulated blades differ in their geometry and technique for tracheal intubation; certain patient populations may benefit from one blade type over another. The primary objective of this systematic review was to assess whether published meta-analyses comparing direct Macintosh laryngoscopy to videolaryngoscopy have accounted for the videolaryngoscope blade type. Secondary objectives evaluated heterogeneity among practitioner experience and specialty, clinical context, patient population, and original primary study outcomes.

SOURCE

A search was performed across Ovid Medline, Ovid Embase, ClinicalKey, PubMed, TRIP, AccessAnesthesiology, Google Scholar, and ANZCA discovery. A systematic review identified meta-analyses which compared direct Macintosh laryngoscopy to videolaryngoscopy. There were no patient age or clinical specialty restrictions. Exclusion criteria included non-English language, studies comparing non-Macintosh blade to videolaryngoscopy, and studies in awake patients.

PRINCIPAL FINDINGS

Twenty-one meta-analyses were identified that were published between 1 January 2000 and 7 May 2020. Macintosh and hyperangulated videolaryngoscope blades were combined in most studies (16/21; 76%). Heterogeneity was also present among practitioner experience (20/21; 95%), clinician specialty (15/21; 71%), and clinical locations (10/21; 48%). Adult and pediatric patients were combined or not defined in 5/21 studies (24%). The primary outcomes of the meta-analyses varied, with the most common (7/21; 33%) being first-pass tracheal intubation success.

CONCLUSIONS

Heterogeneity across important clinical variables is common in meta-analyses comparing direct Macintosh laryngoscopy to videolaryngoscopy. To better inform patient care, future videolaryngoscopy research should differentiate blade type, clinical context, and patient-related primary outcomes.

Canadian Airway Focus Group updated consensus-based recommendations for management of the difficult airway: part 1. Difficult airway management encountered in an unconscious patient

PURPOSE

Since the last Canadian Airway Focus Group (CAFG) guidelines were published in 2013, the literature on airway management has expanded substantially. The CAFG therefore re-convened to examine this literature and update practice recommendations. This first of two articles addresses difficulty encountered with airway management in an unconscious patient.

SOURCE

Canadian Airway Focus Group members, including anesthesia, emergency medicine, and critical care physicians, were assigned topics to search. Searches were run in the Medline, EMBASE, Cochrane Central Register of Controlled Trials, and CINAHL databases. Results were presented to the group and discussed during video conferences every two weeks from April 2018 to July 2020. These CAFG recommendations are based on the best available published evidence. Where high-quality evidence was lacking, statements are based on group consensus.

FINDINGS AND KEY RECOMMENDATIONS

Most studies comparing video laryngoscopy (VL) with direct laryngoscopy indicate a higher first attempt and overall success rate with VL, and lower complication rates. Thus, resources allowing, the CAFG now recommends use of VL with appropriately selected blade type to facilitate all tracheal intubations. If a first attempt at tracheal intubation or supraglottic airway (SGA) placement is unsuccessful, further attempts can be made as long as patient ventilation and oxygenation is maintained. Nevertheless, total attempts should be limited (to three or fewer) before declaring failure and pausing to consider "exit strategy" options. For failed intubation, exit strategy options in the still-oxygenated patient include awakening (if feasible), temporizing with an SGA, a single further attempt at tracheal intubation using a different technique, or front-of-neck airway access (FONA). Failure of tracheal intubation, face-mask ventilation, and SGA ventilation together with current or imminent hypoxemia defines a "cannot ventilate, cannot oxygenate" emergency. Neuromuscular blockade should be confirmed or established, and a single final attempt at face-mask ventilation, SGA placement, or tracheal intubation with hyper-angulated blade VL can be made, if it had not already been attempted. If ventilation remains impossible, emergency FONA should occur without delay using a scalpel-bougie-tube technique (in the adult patient). The CAFG recommends all institutions designate an individual as "airway lead" to help institute difficult airway protocols, ensure adequate training and equipment, and help with airway-related quality reviews.

The VL3 videolaryngoscope for tracheal intubation in adults: A prospective pilot study

Background:

Videolaryngoscopy (VLS) is recommended by international guidelines for the management of difficult airways. We conducted an observational prospective pilot study to assess the efficacy of the new VL3 videolaryngoscope for routine tracheal intubation (TI) in adults; in terms of success rate, the number of attempts, and maneuver duration, including both normal and difficult airways.

Methods:

This prospective observational pilot study comprised a sample of 56 adult patients undergoing elective general anesthesia. For each patient, we performed VLS by VL3 recording the following data: successful TI rate, number of attempts, time of intubation, time to glottis visualization, Cormack-Lehane grade (CL), need for external laryngeal pressure, and presence of post-laryngoscopy side effects.

Results:

TI was successfully carried out in the totality of patients. In only 4 out of 56 cases, the VL3 offered a CL II. The first attempt intubation was achieved in 48 patients (85.7%). In one case, external laryngeal pressure was needed. No CL III or CL IV were observed. We did not find any significant difference between the predicted difficult airways sample and the rest of the population.

Conclusion:

VL3 videolaryngoscope showed to be an effective and safe device for routine TI, even in those patients with predicted difficult airway. More studies are needed to confirm our findings and verify its efficacy even in other settings.

Comparison of Direct and Video Laryngoscopes during Different Airway Scenarios Performed by Experienced Paramedics: A Randomized Cross-Over Manikin Study

Introduction. Airway management plays an essential role in anaesthesia practice, during both elective and urgent surgery procedures and emergency medicine.

Comparison of direct laryngoscope and McGrath videolaryngoscope in terms of glottic view and hemodynamics in bariatric surgery

Background/aim

In the recent years, videolaryngoscopes (VL) have emerged as alternative devices to direct laryngoscopes (DL) in difficult intubation situations. Therefore, we aimed to compare the Macintosh DL and McGrath VL in terms of the glottic image quality, intubation success, intubation time, hemodynamic response after intubation, and complications in bariatric surgery patients.

Material and methods

After obtaining approval by the ethics committee and receiving informed consent, we recorded the demographic and physical data of patients undergoing bariatric surgery. Patients were divided into 2 groups: Group M was intubated with the Macintosh DL, and Group V was intubated with the McGrath VL. After intubation, we noted the Cormack–Lehane score, the duration of intubation, the number of intubation interventions, and the hemodynamic data of patients.

Results

A total of 62 patients (ASA II, body mass index of >35 kg/m2) were included in the study. All patients except 1 patient were intubated on the first attempt. Although there was a decrease in heart rate and blood pressure with induction, similar hemodynamic data were obtained between groups during the operation. In group V, we obtained a better glottic image (P = 0.011), but intubation success was similar between the study groups. We also measured the intubation time in group M as 45.9 ± 19.1 s and group V as 57.1 ± 15.8 s (P = 0.015).

Discussion

Although we measured longer intubation times with the McGrath VL compared with the Macintosh DL, we obtained a better glottic image without causing hemodynamic changes. However, these findings did not make any difference in terms of intubation success.