Complications associated with the use of the GlideScope videolaryngoscope

Video Versus Direct Laryngoscopy for Intubation: Updated Systematic Review and Meta-Analysis

Direct laryngoscopy (DL) is a modality commonly used in endotracheal intubation (EI). Video laryngoscopy (VL) was introduced to further facilitate the procedure with enhancement in glottic views, which captures the video image of the vocal cords to be projected onto a screen, providing enhanced visualization. This real-time video projection aids in accurately placing the endotracheal tube (ETT) through the vocal cords. In emergency and critical care settings, both laryngoscopes are used for intubations. This study assesses the efficacy of both modalities by comparing success rates in first-attempt tracheal intubation in critically ill patients.  PubMed, EMBASE, and Scopus were searched and all randomized controlled trials (RCTs) and observational studies until 2023 were included. Studies included patients in critical care settings undergoing EI under the guidance of either DL or VL. The primary outcome was the first attempt at successful tracheal intubation. The secondary outcomes assessed the comparative safety of DL and VL by comparing the rates of severe hypoxemia, severe hypotension, and cardiac arrest occurring during each modality. P-values were considered of statistical significance if below 0.05. Statistical analysis was performed using RevMan v5.4 (The Nordic Cochrane Centre, The Cochrane Collaboration, Copenhagen, Denmark). The results were displayed in the form of forest plots.  A total of eight studies were included with a total of 5348 patients, with 1780 in the DL group and 3568 in the VL group. Analysis revealed that in emergency situations, the success rate of intubation on the first attempt was significantly higher for VL than DL [81.5% vs 68%; RR= 1.19; 95% CI: 1.10, 1.29; p <0.00001; I2=70%]. There was no significant correlation between VL and severe hypoxemia [13.4% vs 11.6%; RR= 0.99; 95% CI: 0.74, 1.33; p =0.97; I2=46%], severe hypotension [6.09% vs 4.78%; RR:1.19; 95% CI: 0.83, 1.72; p =0.35, I2-15%], and cardiac arrest, [0.8% vs 0.4%; RR= 1.17; 95% CI: 0.37, 3.70]; p =0.79; I2=0%]. Our meta-analysis confirmed that VL has a higher success rate for first-pass intubation than DL. Furthermore, our analysis has shown no significant evidence linking VL to any adverse events.

Airway Management: The Current Role of Videolaryngoscopy

Airway management is usually an uncomplicated and safe intervention; however, when problems arise with the primary airway technique, the clinical situation can rapidly deteriorate, resulting in significant patient harm. Videolaryngoscopy has been shown to improve patient outcomes when compared with direct laryngoscopy, including improved first-pass success at tracheal intubation, reduced difficult laryngeal views, reduced oxygen desaturation, reduced airway trauma, and improved recognition of oesophageal intubation. The shared view that videolaryngoscopy affords may also facilitate superior teaching, training, and multidisciplinary team performance. As such, its recommended role in airway management has evolved from occasional use as a rescue device (when direct laryngoscopy fails) to a first-intention technique that should be incorporated into routine clinical practice, and this is reflected in recently updated guidelines from a number of international airway societies. However, currently, overall videolaryngoscopy usage is not commensurate with its now widespread availability. A number of factors exist that may be preventing its full adoption, including perceived financial costs, inadequacy of education and training, challenges in achieving deliverable decontamination processes, concerns over sustainability, fears over "de-skilling" at direct laryngoscopy, and perceived limitations of videolaryngoscopes. This article reviews the most up-to-date evidence supporting videolaryngoscopy, explores its current scope of utilisation (including specialist techniques), the potential barriers preventing its full adoption, and areas for future advancement and research.

A manikin study comparing the performance of traditional Macintosh laryngoscope, GlideScope®, Airtraq®, and video-optical intubation stylet in endotracheal intubation used by emergency doctors in simulated difficult airway intubation: A pilot study

Background:

The video-optical intubation stylet (VS) is a slim, rigid but flexible intubating device that aids physicians to intubate patients, particularly with difficult airways.

Objectives:

The objective of this study was to compare the performance of emergency department doctors in using different intubating devices for intubation in an airway manikin simulating different difficult airway scenarios.

Methods:

Thirty emergency department doctors were recruited in a pilot study. Their performance of using traditional Macintosh laryngoscope, GlideScope®, Airtraq® and C-MAC® Video Stylet were compared in three situations: normal, restricted cervical motion and limited oral aperture. The time for intubation, first attempt success rate, failure rate, dental injury and the subjective ease of different devices by the participants were compared.

Result:

The mean intubation time by VS in each scenario was significantly shorter compared with other devices (Normal: 19.77s vs 24.67–28.19s, p = 0.014; Cervical restriction: 20.85 vs 26.17–31.26s, p = 0.008; Limited oral aperture:19.03 vs 29.35, p = 0.001). However, there was no significant difference in failure rate or first attempt success rate. The incidence of dental injury was significantly lower with VS than other laryngoscopes (p = 0.001, p < 0.05 and p < 0.05 in normal, cervical restriction and limited oral aperture scenarios, respectively). Moreover, participants appreciated that VS was the easiest device to intubate in each scenario. (p < 0.05 in all scenarios)

Conclusion:

The performance of VS was comparable to or even better than the commonly used laryngoscopes in the emergency department in airway management. When adequate training is provided, VS can be a potentially good alternative for tracheal intubation in different situations.

Updated guideline on equipment to manage difficult airways: Australian and New Zealand College of Anaesthetists

The Australian and New Zealand College of Anaesthetists (ANZCA) recently reviewed and updated the guideline on equipment to manage a difficult airway. An ANZCA-established document development group, which included representatives from the Australasian College for Emergency Medicine and the College of Intensive Care Medicine of Australia and New Zealand, performed the review, which is based on expert consensus, an extensive literature review, and bi-nationwide consultation. The guideline (PG56(A) 2021, https://www.anzca.edu.au/getattachment/02fe1a4c-14f0-4ad1-8337-c281d26bfa17/PS56-Guideline-on-equipment-to-manage-difficult-airways) is accompanied by a detailed background paper (PG56(A)BP 2021, https://www.anzca.edu.au/getattachment/9ef4cd97-2f02-47fe-a63a-9f74fa7c68ac/PG56(A)BP-Guideline-on-equipment-to-manage-difficult-airways-Background-Paper), from which the current recommendations are reproduced on behalf of, and with the permission of, ANZCA. The updated 2021 guideline replaces the 2012 version and aims to provide an updated, objective, informed, transparent, and evidence-based review of equipment to manage difficult airways.

[Tracheal rupture following endotracheal intubation for an emergency cesarean]

This is a case report of a 45-year-old patient, 39 weeks of gestation, who was intubated via rapid sequence induction (RSI) for an emergency cesarean. The indication for emergency cesarean was a pathological cardiotocography during the ejection phase following labor induction.Despite the primary use of a video laryngoscope, there was difficulty aligning the laryngeal axis. Therefore, an internal stylet was used to heavily angulate the endotracheal tube (ETT) to a hockey stick shape to enter the larynx.Postoperative dyspnea and extensive facial swelling were initially diagnosed as an allergic reaction. Only 22 h later the diagnosis of tracheal rupture was confirmed following computer tomography.We hypothesized that the mechanism of injury was due to excessive pressure transmitted to the tip of the ETT. This probably occurred due to a leverage effect caused by the withdrawal of the heavily bent stylet from the ETT, forcing an intratracheal cranial movement of the ETT.By conducting an experiment on a pig's trachea, we were able to visualize this mechanism of injury. In addition, we were able to demonstrate that bending the stylet to a similar angle as the laryngoscope blade led to minimal movement of the tip of the ETT.Therefore, when using a stylet during intubation, we recommend bending the ETT and stylet to the shape of the used laryngoscope blade and retracting the stylet at a similar angle to avoid complications, such as tracheal rupture.

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

Background

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

Methods

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

Results

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

Conclusions

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

Deep neck abscess after intubation trauma: a case report

Significant injuries from endotracheal intubation are exceedingly rare but can lead to life-threatening complications, such as pharyngeal perforation. This type of perforation can result in abscess formation and airway compromise. Risks for this complication include operator skill and intubation in emergent situations. This case report details a 59-year-old male who underwent elective septoplasty with bilateral nasal turbinate reduction. The procedure required general anesthesia induction and endotracheal intubation. He developed a gradually enlarging right-sided neck mass with associated fevers, neck pain, odynophagia, and dysphonia. He presented to the emergency department on postoperative day 5 and was diagnosed with a right-sided, prevertebral space abscess with airway mass effect secondary to pharyngeal perforation. He was admitted for operative management, intravenous antibiotics, and was successfully treated. While significant injury from endotracheal intubation is rare, it can result in infection and threaten airway patency. Emergency physicians must recognize pharyngeal perforation as a potential source of infection following instrumentation of the pharynx. This case has been reported to increase awareness of the potential for such injury.

A comparative study of the efficacy of Glidescope versus Macintosh direct laryngoscopy for intubation in pediatric patients undergoing cardiac surgery

Background:

The Glidescope is a novel, portable, reusable video laryngoscope that has provided superior laryngeal visualization to facilitate tracheal intubation, especially in the management of difficult airways. In this study, we aimed to compare the efficacy of the Glidescope (video-laryngoscope) against the Macintosh direct laryngoscope.

Methods:

Fifty patients were randomly selected via simple randomization using computer-generated random numbers, and sorted into two groups of 25 patients: the Glidescope group and the Macintosh group. We included pediatric patients undergoing cardiac surgery for the repair of congenital heart disease. Those with suspected difficult intubation, preterm babies with low body weight, and patients at risk of aspiration were all excluded.

Results:

Patients’ baseline demographic and clinical characteristics were found to be comparable in the two groups. The mean intubation time was 24.1 ± 13.6 s in the Glidescope group, as compared to 18.1 ± 5.9 s in the Macintosh group. Blade insertion was easy in 92% and 96% of the patients in the Glidescope and Macintosh groups, respectively. Tracheal intubation was considered easy in 84% of the Glidescope group, compared to 92% of the Macintosh group. There was a statistically significant correlation between the ease of tracheal intubation and the used intubation method (rho = –0.35; P = 0.014).

Conclusion:

Our findings indicate that the Glidescope can be used as an efficient modality for obtaining successful intubations with no complications. Ease of tracheal intubation was the only outcome that was found to be affected by the used modality. Further investigations with proper sample sizes are needed.

Soft palate perforation from Glidescope® intubation: A case report

We highlight a potential major complication from GlideScope intubation-perforation of the soft palate. With increasing use of video laryngoscopy, precautions must be taken to ensure that its continued use does not increase airway complications.

Comparing the first-attempt tracheal intubation success of the hyperangulated McGrath® X-blade vs the Macintosh-type CMAC videolaryngoscope in patients with cervical immobilization: a two-centre randomized controlled trial

We compared the hyperangulated McGrath X-blade with the Macintosh-type CMAC videolaryngoscope through the use of manual in-line stabilization on patients. The primary hypothesis was that the McGrath X-blade has a similar first-attempt success rate as the CMAC videolaryngoscope. 210 patients of ASA physical status I to III, aged 21 to 80 years old, undergoing general anesthesia requiring tracheal intubation were prospectively recruited into this two-centre randomized controlled trial, from June 2016 to April 2019. Patients with history of or predicted difficult airway, pre-existing dental risks, BMI > 35 kg/m², cervical spondylosis or myelopathy, aspiration risks, patients who declined to participate or lacked the mental capacity to give consent were excluded. Participants were intubated using either hyperangulated McGrath X-blade (MGX) or Macintosh-type CMAC (CM) videolaryngoscopy, with manual in-line stabilization. Primary outcome measured was first-attempt tracheal intubation success. Secondary outcomes included overall successful intubation within 2 attempts or 120 s, time to intubation, glottic view obtained and intubation-related complications. First-attempt success rates were 71.4% in the MGX group vs. 79.0% in the CM group (p = 0.26), with an absolute difference of -7.6% (95%CI -20%, 5.0%, p value = 0.26), but this trial was underpowered to detect a difference. Overall success was 91.4% (MGX) vs. 92.4% (CM) (p > 0.99). The Cormack & Lehane laryngeal grade was superior in the MGX group compared to CM group (Grade I: MGX 44%, CM 23%; Grade II: MGX 53%, CM 45%; Grade III: MGX 3%, CM 32%; p < 0.001). The median time to intubation using the MGX was longer than the CM [MGX 55.5 s (42.1-78.3), CM 43.8 s (38-55.3); p < 0.001]. Our study did not demonstrate a significant difference in efficacy between the McGrath X-blade and the CMAC videolaryngoscope. In patients with manual in-line stabilization, no anticipated airway difficulty and in the hands of experienced operators, the McGrath X-blade provided superior glottic views but conferred no advantage over the C-MAC, with a longer median time to intubation compared to the CMAC videolaryngoscope.Trial registration: Australian New Zealand Clinical Trial Registry (ACTRN12616000668404).

Awake tracheal intubation with the ProVu™ video stylet: a case series

Management of the difficult airway is integral to peri-operative practice. The development of devices to simplify airway handling are changing our approach to tracheal intubation. We report a case series of three patients who underwent awake tracheal intubation with the ProVu™ video stylet (Flexicare Medical Ltd, Mountain Ash, UK). All three patients had predicted difficult airways, including: limited mouth opening secondary to radiotherapy; previous exenteration, hemi-maxillectomy and scapular free flap formation; and cervical fixation. Awake tracheal intubation was performed successfully in all three cases, with no complications reported. This is the first reported case series of the ProVu™ video stylet as an awake tracheal intubation device. The benefits and limitations of this video stylet are discussed.

Evolution of videolaryngoscopy in pediatric population

Direct laryngoscopy has remained the sole method for securing airway ever since the inception of endotracheal intubation. The recent introduction of video-laryngoscopes has brought a paradigm shift in the pratice of airway management. It is claimed that they improve the glottic view and first pass success rates in adult population. The airway management in children is more challenging than adults. The role of videolaryngoscopy for routine intubation in children is not clearly proven. This review attempts to discuss various videolaryngosocpes available for use in pediatric patients.

Comparison of two different shapes of stylets for intubation with the McGrath MAC® video laryngoscope: a randomized controlled trial

Objective

This study was performed to compare two different shapes of stylets, 60° and J-shaped stylets, for intubation using the McGrath MAC® video laryngoscope (MVL).

Methods

Two hundred twenty-two patients undergoing surgery under general anesthesia were randomly allocated to Group J (n = 111) or Group 60° (n = 111) and intubated using the MVL with the stylet bent into the allocated shape. The time to intubation (TTI) and other intubating profiles were compared between the groups. Multivariate regression analysis was used to determine the relationship between factors related to difficult intubation and TTI.

Results

The TTI was not different between the two groups. There were also no differences in the intubating profiles between the two groups. In both groups, the TTI was longer with a modified Mallampati score (mMS) of ≥3 and percentage of glottic opening (POGO) score of <50. In Group J, the TTI was longer with a body mass index (BMI) of ≥30 kg/m².

Conclusion

The TTI during tracheal intubation with the MVL was not different between the two groups. The TTI was longer with an mMS of ≥3 and POGO score of <50. In Group J, the TTI was longer with a BMI of ≥30 kg/m².

Simultaneous en bloc endotracheal tube insertion with GlideScope® Titanium™ video laryngoscope use: a randomized-controlled trial

PURPOSE

Intubation-associated trauma with the GlideScope is rare, but when it occurs, it is likely due to advancing the endotracheal tube (ETT) blindly between the direct view of the oropharynx and the video view of the glottis. It is also occasionally difficult to advance the ETT to the glottic aperture despite a good view of the glottis on the monitor. One technique to potentially address both issues is to introduce the ETT en bloc with the GlideScope, thus visualizing the ETT tip throughout its entire path. We hypothesized that this en bloc technique could be faster and potentially easier than the standard technique.

METHODS

Fifty patients with normal-appearing airways who required orotracheal intubation for elective surgery were randomly allocated to intubation with either the en bloc or the standard (GlideScope-first-then-ETT) technique. A three-dimensional printed clip was utilized to secure the ETT to the GlideScope during en bloc insertion. The primary outcome was time to intubation, defined from mask removal to first end-tidal carbon dioxide detection, recorded by a blinded observer. Secondary outcomes were subjective ease of intubation (100-mm visual analogue scale [VAS], 0 = easy; 100 = difficult), number of intubation attempts/failures, and incidence of oropharyngeal trauma (bleeding).

RESULTS

The median [interquartile range (IQR)] intubation time was 36 [31-42] sec with the en bloc technique vs 41 [37-50] sec with the standard technique (difference in medians, 5 sec; 95% confidence interval [CI], 2 to 11; P = 0.008). The median [IQR] ease of intubation VAS was 11 [9-21] mm with the en bloc technique, and 15 [11-24] mm with the standard technique (difference in medians, 4 mm; 95% CI, -2 to 8; P = 0.19). Laryngoscopic grade and number of intubation attempts were similar between the groups; there was no oropharyngeal trauma noted.

CONCLUSION

In this study of video laryngoscopy, intubation was slightly faster with the en bloc technique than with the standard GlideScope intubation technique, although the clinical importance of this difference is unknown.

TRIAL REGISTRATION

www.clinicaltrials.gov (NCT02787629); registered 1 June 2016.

Utility of videolaryngoscopy for diagnostic and therapeutic interventions in head and neck surgery

BACKGROUND

Videolaryngoscopy is commonly used by anesthesiologists to manage difficult airways. Recently otolaryngologists have reported use in select procedures; to date there is limited evaluation in head and neck surgery.

MATERIALS AND METHODS

Patients who underwent direct laryngoscopy (DL) with use of GlideScope videolaryngoscopy (GVL) were retrospectively identified from a tertiary care Veterans Affairs hospital. GVL was used to assist or replace traditional laryngoscopes for diagnostic and therapeutic procedures.

RESULTS

Nineteen patients (48-83 years old) underwent 21 procedures. Difficult endotracheal intubation was reported in 53% of patients. GVL replaced traditional DL in 76% of cases, assisted evaluation prior to traditional DL in 10%, and rescued failed traditional DL in 14%. No complications occurred. Three indications for GVL were identified.

DISCUSSION

GVL was safe in our experience and provides unique benefits in selected scenarios in head and neck surgery. Otolaryngologists can consider videolaryngoscopy as a complement to traditional DL.

Recommendations for the evaluation and management of the anticipated and non-anticipated difficult airway of the Societat Catalana d'Anestesiologia, Reanimació i Terapèutica del Dolor, based on the adaptation of clinical practice guidelines and expert consensus

The Airway Division of the Catalan Society of Anaesthesiology, Intensive Care and Pain Management (SCARTD) presents its latest guidelines for the evaluation and management of the difficult airway. This update includes the technical advances and changes observed in clinical practice since publication of the first edition of the guidelines in 2008. The recommendations were defined by a consensus of experts from the 19 participating hospitals, and were adapted from 5 recently published international guidelines following an in-depth analysis and systematic comparison of their recommendations. The final document was sent to the members of SCARTD for evaluation, and was reviewed by 11 independent experts. The recommendations, therefore, are supported by the latest scientific evidence and endorsed by professionals in the field. This edition develops the definition of the difficult airway, including all airway management techniques, and places emphasis on evaluating and classifying the airway into 3 categories according to the anticipated degree of difficulty and additional safety considerations in order to plan the management strategy. Pre-management planning, in terms of preparing patients and resources and optimising communication and interaction between all professionals involved, plays a pivotal role in all the scenarios addressed. The guidelines reflect the increased presence of video laryngoscopes and second-generation devices in our setting, and promotes their routine use in intubation and their prompt use in cases of unanticipated difficult airway. They also address the increased use of ultrasound imaging as an aid to evaluation and decision-making. New scenarios have also been included, such as the risk of bronchoaspiration and difficult extubation Finally, the document outlines the training and continuing professional development programmes required to guarantee effective and safe implementation of the guidelines.

Upper airway tract complications of endotracheal intubation

The gold standard in airway maintenance is translaryngeal endotracheal intubation, but this is not without its complications. Trauma to the upper airway as a result of the act of endotracheal intubation is a common event in adults undergoing procedures under general anaesthesia. Sites requiring attention during intubation include the laryngeal apparatus, the pharynx and oral cavity as well as the nasal cavity when nasopharyngeal intubation is performed. Patients can present with a range of symptoms which can make assessment and management challenging. Dysphonia, throat pain and dysphagia are the commonest presenting complaints. Patient-related factors, intubation technique and other anaesthetic-related conditions can be a cause of trauma, if not adequately considered before intubation. All patients should be carefully examined preoperatively and their past medical history obtained. Patient demographics, comorbidities, existing airway pathology and presence of reflux should be noted. Trauma prevention strategies should be in place to eliminate avoidable complications. Potential difficult airway cases should be flagged up and adequately prepared for, in anticipation of intubation difficulties that can lead to trauma. The majority of injuries will resolve spontaneously with conservative management. Persistent symptomatology, usually secondary to laryngeal injuries, requires prompt referral to an ear nose and throat specialist with an interest in laryngology for further assessment and treatment.

Role of playback videolaryngoscope footage in improved patient care

Despite the frequency of videolaryngoscope use, to the authors’ knowledge, there are no publications exploring the role of playback video recording in real time to improve patient care. We present a patient with a difficult airway complicated by trauma during GlideScope® (Verathon Inc., Bothell, WA, USA) intubation. The injury was not recognised by any of the anaesthetic staff observing the intubation, and was only identified when playback video footage was viewed. This provided the opportunity for early ear, nose and throat surgical review prior to extubation. Airway trauma can be missed by the anaesthetist. Reviewing video playback footage at an appropriate time during the case may enable more timely recognition of airway injuries and, ultimately, improved patient care.

Fibreoptic intubation in airway management: a review article

Since the first use of the flexible fibreoptic bronchoscope, a plethora of new airway equipment has become available. It is essential for clinicians to understand the role and limitations of the available equipment to make appropriate choices. The recent 4th National Audit Project conducted in the United Kingdom found that poor judgement with inappropriate choice of equipment was a contributory factor in airway morbidity and mortality. Given the many modern airway adjuncts that are available, we aimed to define the role of flexible fibreoptic intubation in decision-making and management of anticipated and unanticipated difficult airways. We also reviewed the recent literature regarding the role of flexible fibreoptic intubation in specific patient groups who may present with difficult intubation, and concluded that the flexible fibrescope maintains its important role in difficult airway management.

Video laryngoscopy versus direct laryngoscopy for first-attempt tracheal intubation in the general ward

Background

Recent trials showed that video laryngoscopy (VL) did not yield higher first-attempt tracheal intubation success rate than direct laryngoscopy (DL) and was associated with higher rates of complications. Tracheal intubation can be more challenging in the general ward than in the intensive care unit. This study aimed to investigate which laryngoscopy mode is associated with higher first-attempt intubation success in a general ward.

Methods

This is a retrospective study of tracheal intubations conducted at a tertiary academic hospital. This analysis included all intubations performed by the medical emergency team in the general ward during a 48-month period.

Results

For the 958 included patients, the initial laryngoscopy mode was video laryngoscopy in 493 (52%) and direct laryngoscopy in 465 patients (48%). The overall first-attempt success rate was 69% (664 patients). The first-attempt success rate was higher with VL (79%; 391/493) than with DL (59%; 273/465, p < 0.001). The first-attempt intubation success rate was higher among experienced operators (83%; 266/319) than among inexperienced operators (62%; 398/639, p < 0.001). In multivariate logistic regression analyses, VL, pre-intubation heart rate, pre-intubation SpO₂ > 80%, a non-predicted difficult airway, experienced operator, and Cormack–Lehane grade were associated with first-attempt intubation success in the general ward. Over all intubation-related complications were not different between two groups (27% for VL vs. 25% for DL). However, incidence of a post-intubation SpO₂ < 80% was higher with VL than with DL (4% vs. 1%, p = 0.005), and in-hospital mortality was also higher (53.8% vs. 43%, p = 0.001).

Conclusion

In a general ward setting, the first-attempt intubation success rate was higher with video laryngoscopy than with direct laryngoscopy. However, video laryngoscopy did not reduce intubation-related complications. Furthers trials on best way to perform intubation in the emergency settings are required.

Electronic supplementary material

The online version of this article (10.1186/s13613-018-0428-0) contains supplementary material, which is available to authorized users.

A prospective randomized controlled study to evaluate and compare GlideScope with Macintosh laryngoscope for ease of endotracheal intubation in adult patients undergoing elective surgery under general anesthesia

Background:

The aim of the study was to compare the ease the intubation using GlideScope video laryngoscope and Macintosh laryngoscope in adult patients undergoing elective surgery under general anesthesia.

Materials and Methods:

A total of 200 American Society of Anesthesiologists I–II patients of either sex, in the age group of 18–60 years were included in the study. Patients were randomly allocated to two groups. We assessed ease of intubation depending on time to tracheal intubation, number of attempts, glottic view (Cormack–Lehane grade [CL grade] and percentage of glottis opening [POGO]) and intubation difficulty score (IDS), hemodynamic variables and any intra- and post-operative adverse events.

Results:

The rate of successful endotracheal intubation (ETI) in both groups was 100% in the first attempt. The time required for successful ETI was 24.89 ± 5.574 in Group G and 20.68 ± 3.637 in Group M (P < 0.001) found to be statistically significant. There was significant improvement in glottic view with GlideScope (as assessed by POGO score 66.71 ± 29.929 and 94.40 ± 10.476 in group G and 75.85 ± 26.969 and 74.20 ± 29.514 Group M and CL grading [P < 0.001]). A comparison of mean IDS between two groups revealed intubation was easier with the use of GlideScope. The hemodynamic response to intubation was significantly lesser with the use of GlideScope when compared with Macintosh laryngoscope. The incidence of adverse events, though minor like superficial lip or tongue bleed, was similar in two groups.

Conclusions:

GlideScope offers superiority over Macintosh laryngoscope in terms of laryngeal views and the difficulty encountered at ETI in an unselected population.

Stylet angulation of 70 degrees reduces the time to intubation with the GlideScope®: A prospective randomised trial

Objective

The GlideScope® videolaryngoscope provides a good view of the glottis. However, directing and inserting an endotracheal tube is sometimes difficult during intubation with the GlideScope®. In this study, we compared two GlideScope® stylet angulations (90° vs. 70°) in terms of the time to intubation.

Methods

In total, 162 patients scheduled for elective surgery under general anaesthesia were randomly assigned to one of two groups. In the 90 group (n = 79), a 90° stylet was used. In the 70 group (n = 78), a 70° stylet was used. The time to intubation was recorded. The number of intubation attempts was assessed.

Results

The time to intubation was significantly shorter in the 70 than 90 group [26.0 (23.0–32.0) vs. 37.0 (30.0–43.0) s, respectively]. The first-time intubation success rate was significantly higher and the number of failed intubations was significantly lower in the 70 than 90 group (100% vs. 87% and 0% vs. 6%, respectively).

Conclusions

This investigation suggests that a 70° angle stylet is superior to a 90° angle stylet for GlideScope® intubation.

Trial Registration Clinicaltrials.gov Identifier: NCT02547064

Guidelines and algorithms for managing the difficult airway

The difficult airway constitutes a continuous challenge for anesthesiologists. Guidelines and algorithms are key to preserving patient safety, by recommending specific plans and strategies that address predicted or unexpected difficult airway. However, there are currently no "gold standard" algorithms or universally accepted standards. The aim of this article is to present a synthesis of the recommendations of the main guidelines and difficult airway algorithms.

Assessment of awake i-gel™ insertion for fiberoptic-guided intubation in patients with predicted difficult airway: A prospective, observational study

Background and Aims:

Orotracheal intubation (OTI) with fiberoptic bronchoscope (FOB) in spontaneous ventilation is one of the main techniques for patients with predicted difficult airway. Latest generation supraglottic airway devices have been designed to allow OTI through them. We assessed the safety and effectiveness of FOB-guided OTI through i-gel™ device which was inserted in spontaneously breathing patients with predicted difficult airway.

Material and Methods:

Eighty-five patients with difficult airway predictors were included. The i-gel was inserted under oropharyngeal local anaesthesia and sedation. After checking the adequate ventilation through the i-gel with capnography curve, general anaesthesia was induced in order to introduce the endotracheal tube guided by FOB. We recorded the i-gel insertion time (t_gel), intubation time (t_int), O₂ saturation in pulse oximetry (SpO₂) at different times: basal (t₀), after 3 min of preoxygenation with a face mask at 100% FiO₂ (t₁), after i-gel mask insertion (t₂) and after intubation (t₃). Adverse events during the procedure were also recorded.

Results:

All patients were successfully intubated. SpO₂ values were: 96.9 ± 1.2 (t₀), 99.0 ± 0.9 (t₁), 96.2 ± 2.4 (t₂), 96.0 ± 2.5 (t₃). t_gel and t_int were 38.0 ± 7.8 s and 36.5 ± 5.6 s, respectively. No serious adverse events were recorded and no patient suffered airway trauma.

Conclusion:

I-gel insertion in spontaneous ventilation secures the airway before achieving fiberoptic intubation without the occurrence of adverse events. More studies might be necessary in order to confirm the results presented, but we consider that the technique described is a safe and effective alternative to classic OTI with FOB in spontaneously breathing patients with predicted difficult airway.

Comparison of the GlideScope® with the Macintosh Laryngoscope in Endotracheal Intubation during Uninterrupted Mechanical Chest Compression: A Randomised Crossover Manikin Study

Background

The GlideScope® (GS) has been shown to improve the first-attempt success rate of endotracheal intubation during continuous mechanical chest compressions compared with the conventional Macintosh laryngoscope (ML) in inexperienced hands. Yet, its value for operators with experience of emergency airway management has remained uncertain. We set out to compare their performance in the hands of experienced operators in a manikin receiving continuous mechanical chest compressions delivered by LUCAS®.

Method

This was a randomised crossover study. Thirty-five emergency physicians and intensivists performed intubation using GS and ML in 3 different scenarios: (1) normal airway without chest compressions; (2) normal airway with uninterrupted mechanical chest compressions; and (3) normal airway with cervical spine (C-spine) immobilisation and uninterrupted mechanical chest compressions. The sequence of scenarios and devices used were randomised. The primary outcome was the first-attempt success rate of intubation. Other data including demographics, the time required for successful intubation, complications during intubation, the visual analog scale of perceived difficulty of intubation and the preference on devices in each scenario were also collected and analyzed.

Results

In scenario 1, the first-attempt success rate with both laryngoscopes was 100%. In scenario 2, there was a higher first-attempt success rate with ML but it was not statistically significant (GS 97.14% vs ML 100%, p=1.00). In scenario 3, one participant failed to intubate in the first attempt with each of the laryngoscopes (GS 97.14% vs ML 97.14%, p=0.754). More dental compression was noted with GS but the difference was not statistically significant (GS 42.86% vs ML 22.86%, p=0.126). Overall, the median time for intubation with GS was significantly longer in all 3 scenarios (Scenario 1: GS 18.5s; interquartile range [IQR] 13.8 -22.2s vs ML 11.2s, IQR 9.5-14.2s, p<0.001; Scenario 2: GS 18.7s, IQR 13.1-25.2s vs ML 13.4s, 10.3-15.8s, p<0.001; Scenario 3: GS 20.8s, IQR 16.5-29.2s vs ML 14.0s, IQR 10.5-18.0s, p<0.001). More participants preferred GS in scenario 3, while ML remained the device of choice in the other two scenarios. Conclusion: GS is not superior to ML in terms of the first-attempt success rate of intubation and it takes significantly longer to intubate for experienced operator. Yet more participants prefer its use when the C-spine motion is limited. Further studies are warranted to explore its role in trauma resuscitation. (Hong Kong j.emerg.med. 2016;23:159-167)

Fiberoptic bronchoscope and C-MAC video laryngoscope assisted nasal-oral tube exchange: two case reports

In cases of multiple facial trauma and other specific cases, the anesthesiologist may be asked to convert an oral endotracheal tube to a nasal endotracheal tube or vice versa. Conventionally, the patient is simply extubated and the endotracheal tube is re-inserted along either the oral or nasal route. However, the task of airway management can become difficult due to surgical trauma or worsening of the airway condition. Fiberoptic bronchoscopy was considered a novel method of airway conversion but this method is not useful when there are secretions and bleeding in the airway, or if the anesthesiologist is inexperienced in using this device. We report a successful airway conversion under the aid of both, a fiberoptic bronchoscope and a C-MAC video laryngoscope.

Arytenoid cartilage dislocation mimicking bilateral vocal cord paralysis: A case report

RATIONALE

Arytenoid dislocation is very rare and may be misdiagnosed as vocal cord paralysis or a self-limiting sore throat.

PATIENT CONCERNS

A 70-year-old male (70 kg, 156 cm) was scheduled for transurethral resection of bladder tumors. A McGrath videolaryngoscope, with a basic cuffed Mallinckrodt oral tracheal tube of 7.5 mm internal diameter, was used to successfully intubate his trachea. The duration of surgery was 25 minutes. In the recovery room, he complained of sore throat and dyspnea with inspiratory stridor, which were not resolved after intravenous injection of 10 mg of dexamethasone.

DIAGNOSES

The otolaryngological examination revealed midline fixation of the bilateral vocal folds, suggestive of bilateral arytenoid dislocation or bilateral vocal cord palsy. The latter was ruled out because there was no evidence of recurrent laryngeal nerve injury.

INTERVENTIONS

Under general anesthesia, a closed reduction was performed using laryngoscopic forceps to apply posterolateral pressure on the arytenoid joints on both sides. Only the dislocation of the left cricoarytenoid joint could be easily reduced, whereas reduction of the right joint was not possible.

OUTCOMES

On postoperative day 7, examination with a rigid laryngoscope showed a medially fixed right vocal fold, with full compensation by the left vocal fold. Computed tomography of the neck showed no pathologic findings. Six weeks after surgery, the patient had regained his normal voice with no complications.

LESSONS

Although arytenoid dislocation is a rare complication, it should be considered even in patients with uncomplicated tracheal intubation. Early diagnosis and the optimal therapeutic approach are critical for restoration of the patient's original vocal cord function.

Videolaryngoscopy in Neonates, Infants, and Children

Airway management is vital during anesthetic care and during resuscitative efforts in the PICU, the emergency department, and the delivery room. Given specific anatomic and physiologic differences, neonates and infants may be more prone to complications during airway management. Videolaryngoscopy may offer an alternative to or advantages over direct laryngoscopy in specific clinical scenarios. The following article reviews some of the basic types of videolaryngoscopy and discusses their potential applications in the pediatric population.

McGrath Series 5 videolaryngoscope vs Airtraq DL videolaryngoscope for double-lumen tube intubation: A randomized trial

BACKGROUND

Many studies have shown Airtraq videolaryngoscope provided faster tracheal intubation and a higher success rate than other videolaryngoscopes. Recently, different types of videolaryngoscopes have been reported for use in double-lumen tube (DLT) intubation. However, the advantages and disadvantages between them remain undetermined for DLT intubation. In this study, we compared the Airtraq DL videolaryngoscope with the McGrath Series 5 videolaryngoscope for DLT intubation by experienced anesthesiologists.

METHODS

Ninety patients with expected normal airways were randomly allocated to either the Airtraq or McGrath group. The primary outcome was DLT intubation time. The secondary outcomes were glottic view, success rate, subjective ease of intubation (100-mm visual analog scale, 0 = easy; 100 = difficult), incidence of DLT malposition, and postoperative intubation-related complication.

RESULTS

The airway characteristics were comparable between the 2 groups. Cormack and Lehane grades significantly improved with the use of the McGrath and Airtraq videolaryngoscopes, compared with the Macintosh laryngoscope. The intubation success rate on the first attempt was 93% in the Airtraq group and 95% in the McGrath group (P > 0.05). The intubation time in the McGrath group is longer than that in the Airtraq group (39.9 [9.1]s vs 28.6 [13.6]s, P < 0.05). But intubation difficulty score, the incidence of DLT malposition and intubation-related complication were comparable between groups (P > 0.05).

CONCLUSIONS

When using videolaryngoscopes for DLT intubation, the Airtraq DL is superior to the McGrath Series 5 in intubation time, but it does not decrease intubation difficulty.

Soft Palate Injuries During Orotracheal Intubation With the Videolaryngoscope

OBJECTIVE

The videolaryngoscope has gained popularity for providing superior visualization in intubations. A rare complication of this technology is soft palate injury. Through a literature review and case series, we highlight the risks associated with the Glidescope and McGrath videolaryngoscopes and the management of soft palate injuries.

METHOD

A case series of multi-institutional review of medical records was performed to identify patients with soft palate injuries from the videolaryngoscope. A literature review was also performed to analyze risk factors, mechanism of injury, complications, and management of palate injuries.

RESULTS

Of 9 cases, 3 resulted in soft palate perforations, which required primary closure. The remaining 6 patients sustained a soft palate laceration, which was treated conservatively. This injury commonly occurs when the intubator is focused on the video monitor and blindly inserts the Glidescope into the oropharynx. The rigid stylet used with the Glidescope increases the propensity for oropharyngeal injuries during blind insertions.

CONCLUSION

Proper training, an awareness of this potential complication, and direct oral cavity visualization are recommended while inserting the videolaryngoscope. Repair is recommended for through-and-through perforations or if a large hanging flap is present. Antibiotics should be considered for lacerations greater than 1 to 2 cm.

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

Objectives:

To evaluate Parker Flex-It stylet as an alternative to GlideRite Rigid stylet to aid tracheal intubation with the Glidescope.

Methods:

This prospective randomized trial was conducted at King Abdulaziz University Hospital, College of Medicine, King Saud University, Riyadh, Saudi Arabia between May and December 2014. Sixty American Society of Anesthesiologists I-II patients were randomly assigned to one of 2 equal groups receiving intubation by Glidescope using either GlideRite Rigid stylet (Group GS) or Parker Flex-It stylet (Group PS). The total intubation time, ease of intubation, incidences of successful intubation at first attempt, number of intubation attempts, use of optimization maneuvers, and possible complications were recorded.

Results:

No significant differences between both groups regarding the total intubation time (p=0.08) was observed. Intubation was significantly easier in group PS compared with group GS as measured by visual analogue scale (p=0.001) with no significant differences between the groups regarding the rate of successful tracheal intubation from first attempt (p=0.524). However, the number of attempts at intubation and usage of external laryngeal manipulation were similar in both groups (p>0.05). The incidence of sore throat, dysphagia, hoarseness, and trauma were significantly higher in group GS (p<0.05).

Conclusion:

Parker Flex-It stylet is as effective as GlideRite Rigid stylet when used by experienced operators in patients with normal airways using Glidescope; however, it is easier and less traumatic.

Fiberoptic-guided intubation after insertion of the i-gel airway device in spontaneously breathing patients with difficult airway predicted: a prospective observational study

STUDY OBJECTIVE

To assess the viability of performing fiberoptic-guided orotracheal intubation through the i-gel airway device previously inserted in spontaneously breathing patients with predicted difficult airway to achieve a patent airway.

DESIGN

Prospective observational study.

SETTING

Operating room in a tertiary care hospital.

PATIENTS

Eighty-five adult patients with at least 3 difficult airway predictors or difficult airway management history were included.

INTERVENTIONS

The i-gel device was inserted in spontaneous ventilation under oropharyngeal local anesthesia and sedation. After checking the adequate ventilation through the i-gel with capnography curve, general anesthesia was induced to introduce the endotracheal tube guided by fiberoptic bronchoscope.

MEASUREMENTS

We recorded the i-gel insertion time (tgel), intubation time (tint), and O₂ saturation in pulse oximetry in different moments: basal (t0), after 3 minutes of preoxygenation with a face mask at 100% fraction of inspired O₂ (t1), after i-gel mask insertion (t2), and after intubation (t3). Adverse events during the procedure were also recorded, and patient discomfort was questioned.

MAIN RESULTS

All patients were successfully intubated. O₂ saturation in pulse oximetry values were (mean±SD): 96.9±1.22 (t0), 99.0±0.85 (t1), 96.2±2.37 (t2), and 96.0±2.54 (t3). tgel and tint were 38.0±7.76 seconds and 36.5±5.55 seconds (mean±SD), respectively. No serious adverse events were recorded, and no patient suffered airway damage. Visual analogue scale for patient discomfort was 2 (interquartile range, 1-3).

CONCLUSIONS

i-gel insertion in spontaneously breathing patients avoids the "cannot ventilate" scenario. The subsequent fiberoptic-guided intubation through the i-gel is a safe and effective technique. More studies might be necessary to confirm the results presented, but we consider that the technique described is an adequate alternative to classic orotracheal intubation with fiberoptic bronchoscope in spontaneous ventilation for certain patients with predicted difficult airway.

Success of Intubation Rescue Techniques after Failed Direct Laryngoscopy in Adults

Background

Multiple attempts at tracheal intubation are associated with mortality, and successful rescue requires a structured plan. However, there remains a paucity of data to guide the choice of intubation rescue technique after failed initial direct laryngoscopy. The authors studied a large perioperative database to determine success rates for commonly used intubation rescue techniques.

Methods

Using a retrospective, observational, comparative design, the authors analyzed records from seven academic centers within the Multicenter Perioperative Outcomes Group between 2004 and 2013. The primary outcome was the comparative success rate for five commonly used techniques to achieve successful tracheal intubation after failed direct laryngoscopy: (1) video laryngoscopy, (2) flexible fiberoptic intubation, (3) supraglottic airway as part of an exchange technique, (4) optical stylet, and (5) lighted stylet.

Results

A total of 346,861 cases were identified that involved attempted tracheal intubation. A total of 1,009 anesthesia providers managed 1,427 cases of failed direct laryngoscopy followed by subsequent intubation attempts (n = 1,619) that employed one of the five studied intubation rescue techniques. The use of video laryngoscopy resulted in a significantly higher success rate (92%; 95% CI, 90 to 93) than other techniques: supraglottic airway conduit (78%; 95% CI, 68 to 86), flexible bronchoscopic intubation (78%; 95% CI, 71 to 83), lighted stylet (77%; 95% CI, 69 to 83), and optical stylet (67%; 95% CI, 35 to 88). Providers most frequently choose video laryngoscopy (predominantly GlideScope® [Verathon, USA]) to rescue failed direct laryngoscopy (1,122/1,619; 69%), and its use has increased during the study period.

Conclusions

Video laryngoscopy is associated with a high rescue intubation success rate and is more commonly used than other rescue techniques.

Comparing McGRATH® MAC, C-MAC®, and Macintosh Laryngoscopes Operated by Medical Students: A Randomized, Crossover, Manikin Study

We hypothesized that the McGRATH MAC would decrease the time of intubation compared to C-MAC for novices. Thirty-nine medical students who had used the Macintosh blade to intubate a manikin fewer than 3 times were recruited. The participants performed sequential intubations on the manikin in two simulated settings that included a normal airway and a difficult airway (tongue edema). The intubation time, success rate of intubation, Cormack-Lehane grade at laryngoscopy, and difficulty using the device were recorded. Each participant was asked to identify the device that was most useful. The intubation time decreased significantly and by a similar amount to the McGRATH MAC and C-MAC compared to the Macintosh blade (P < 0.001 and P = 0.017, resp.). In the difficult airway, the intubation times were similar among the three devices. The McGRATH MAC and C-MAC significantly increased the success rate of intubation, improved the Cormack-Lehane grade, and decreased the difficulty score compared to the Macintosh blade in both airway settings. The majority of participants selected the McGRATH MAC as the most useful device. The McGRATH MAC and C-MAC may offer similar benefits for intubation compared to the Macintosh blade in normal and difficult airway situations.

Usefulness of video-laryngoscopy with the Airway Scope for intubation performance and learning: an experimental manikin controlled study

Background

Different video-laryngoscopes (VDLs) for endotracheal intubation (ETI) have recently been developed. We compared the performance of the VDL Airway Scope (AWS) with the direct laryngoscopy by Macintosh (DLM) for ETI success, time and learning.

Methods

We performed an experimental manikin controlled study. Twenty experienced (experts) and 40 inexperienced operators (novices) for DLM-ETI were enrolled. None of them had experience with the use of AWS-VDL. Novices were assigned to start learning with DLM or AWS, and two sub-groups of 20 novices were formed. Experts group constituted the control group. Each participant performed 10 ETI attempts with each device on the same standard manikin. The primary endpoint was the ETI success probability. Secondary endpoints were ETI time, technical validity and qualitative evaluation for each technique. We also assessed the learning order and the successive attempts effects for these parameters.

Results

Overall, 1200 ETI attempts were performed. ETI success probability was higher with the AWS than with the DLM for all operators (98 vs. 81 %; p < 0.0001) and for experts compared to novices using devices in the same order (97 vs. 83 %; p = 0.0002). Overall ETI time was shorter with the AWS than with the DLM (13 vs. 20 s; p < 0.0001) and for experts compared to novices using devices in the same order (11 vs. 21 s; p < 0.0001). Among novices, those starting learning with AWS had higher ETI success probability (89 vs. 83 %; p = 0.03) and shorter ETI time (18 vs. 21 s; p = 0.02). Technical validity was found better with the AWS than DLM for all operators. Novices expressed global satisfaction and device preference for the AWS, whereas experts were indifferent.

Conclusions

AWS-VDL permits faster, easier and more reliable ETI compared to the DLM whatever the previous airway ETI experience and could be a useful device for DLM-ETI learning.

Comparison between the Trachway video intubating stylet and Macintosh laryngoscope in four simulated difficult tracheal intubations: A manikin study

OBJECTIVES

It remains to be determined whether the TVI-4000 Trachway video intubating (TVI) stylet (Markstein Sichtec Medical Corp, Taichung, Taiwan), an airway device for novices, improves airway management practice by experienced anesthesiologists. The aim of this study was to evaluate the feasibility of using the TVI stylet in difficult tracheal intubation situations compared with that of using the Macintosh laryngoscope on an airway manikin.

MATERIALS AND METHODS

Ten anesthesiologists (with 3-21 years' experience), including three senior residents, participated. We compared tracheal intubation in four airway scenarios: normal airway, tongue edema, cervical spine immobilization, and tongue edema combined with cervical spine immobilization. The time of tracheal intubation (TTI), success rate, and perceived difficulty of intubation for each scenario were compared and analyzed.

RESULTS

The TTI was significantly shorter in both the tongue edema and combined scenarios with the TVI stylet compared with the Macintosh laryngoscope (21.60 ± 1.45 seconds vs. 24.07 ± 1.58 seconds and 23.73 ± 2.05 seconds vs. 26.6 ± 2.77 seconds, respectively). Success rates for both devices were 100%. Concomitantly, participants rated using the TVI stylet in these two scenarios as being less difficult.

CONCLUSION

The learning time for tracheal intubation using the TVI stylet in difficult airway scenarios was short. Use of the TVI stylet was easier and required a shorter TTI for tracheal intubation in the tongue edema and combined scenarios.