Canadian Airway Focus Group updated consensus-based recommendations for management of the difficult airway: part 2. Planning and implementing safe management of the patient with an anticipated difficult airway

Awake Tracheal Intubation: An Update

Awake tracheal intubation (ATI) remains the "gold standard" technique in securing a definitive airway in conscious, self-ventilating patients with predicted or known difficult airways and the procedure is associated with a low failure rate. Since its inception a variety of techniques to achieve ATI have emerged and there have been accompanying advancements in pharmaceuticals and technology to support the procedure. In recent years there has been a growing focus on the planning, training and human factors involved in performing the procedure. The practice of ATI, does however, remain low around 1% to 2% of all intubations despite an increase in those with head and neck pathology. ATI, therefore, presents a skill that is key for the safety of patients but may not be practised with regularity by many anesthetists. In this article we therefore aim to highlight relevant guidance, recent literature and provide an update on the practical methods fundamental for successful ATI. We also discuss the crucial aspects of a safe airway culture and how this can help to embed training and maintenance of skills.

Perioxygenation During Advanced Airway Management

ABSTRACT

Advanced airway management is a skill that is used every day in patient care settings throughout the world. Albeit common, it is not benign. Advanced airway management may either be elective or urgent; in either case, it may result in significant patient morbiidity and mortality. The complications of difficult or failed endotracheal intubation can be severe and include death or permanent neurologic injury. Difficulty or failure with advanced airway management often coincides with the onset of hypoxia. The onset of hypoxia affects both the patient and the airway manager. While hypoxemia may result in dysrhythmias and ultimately cardiac arrest for the patient, it adds time pressure and stress to the airway manager, and thus may impact successful performance. In this review, we will discuss how to identify patients at risk for rapid desaturation during advanced airway management. Additionally, methods of peri-oxygenation throughout the performance of airway management will be discussed.

Extubation-Related Complications

Extubation represents an essential component of airway management. While being a common procedure in anesthesiology and critical care medicine, it is accompanied by a significant risk of morbidity and mortality. Safe extubation requires considerable skills, risk stratification and advanced planning. It is important to emphasize that intentional extubation is always an elective procedure, and as such should only be executed when conditions are optimal. The purpose of this review is to discuss the complications associated with planned extubation in the adult patient, including risk factors and management strategies, mainly focusing on the postoperative setting.

In the Nick of Time-Emergency Front-of-Neck Airway Access

Emergency front-of-neck access refers to all techniques that deliver oxygen into the airway lumen through the anterior neck structures and encompasses access both through the cricothyroid membrane and the tracheal wall. There has yet to be a universal agreement regarding the preferred technique. A surgical incision is currently the most common approach in prehospital and in-hospital care. This review intends to review and summarize the existing clinical, basic science, and societal guidelines for eFONA.

Clinical Approach to Massive Hemoptysis: Perioperative Focus on Causes and Management

Massive hemoptysis is a time critical airway emergency in the perioperative setting, with an associated mortality exceeding 50%. Causes of hemoptysis in the perioperative setting include procedural complication, coagulopathy, malignancy, chronic lung disease, infection, left-sided cardiac disease, pulmonary vascular disease and autoimmune disease. A rapid and coordinated multidisciplinary response is required to secure the airway, isolate the lung, ensure adequate oxygenation and ventilation, identify the underlying cause and initiate specific systemic, bronchoscopic, endovascular, or surgical treatment. This review examines the etiology, pathophysiology, as well as approach to management and interventions in perioperative massive hemoptysis.

The Difficult Airway in Patients with Cancer

PURPOSE OF REVIEW

The goal of this review is to provide an overview of difficult airway management in the cancer population.

RECENT FINDINGS

Difficult airways can be unanticipated; however, several anatomical and physiological features may predict difficult airway management, with several specific for the cancer patient population. New technologies and techniques for airway management, including non-invasive oxygenation, and even the utilization of ECMO, have led to better outcomes and decreased morbidity. Furthermore, the incorporation of multidisciplinary airway teams has helped reduce morbidity associated with predicted and known difficult airways. Cancer patients may exhibit or develop anatomic and physiologic features that may predispose them to difficulty with airway management. As our technologies for airway management continue to advance, as well as further commitment to more interdisciplinary collaboration, difficult airway management in the cancer population will continue to become safer.

Combined awake videolaryngo-bronchoscopy intubation with HFNC preoxygenation for predicted difficult airway in a patient with post-burn mentosternal scar contracture

Airway management and safety remain a difficult challenge during reconstructive surgery in patients with extensive post-burn mentosternal scar contractures. Current guidelines do not recommend the use of direct laryngoscopy for predicted difficult airway because of the risk of intubation failure and airway emergencies: the consequences of wrong decisions can be fatal, and the patient is at serious risk. At present, video-laryngoscopy is the most commonly used technique for routine orotracheal intubation. Awake tracheal intubation with fibro-bronchoscopy also remains a valid option when possible, ensuring the patient's spontaneous breathing during the procedure. However, when videolaryngoscopy is used in combination with this method, the efficiency of these devices can be increased, and a better result can be achieved. We report a case of successful management of a predicted difficult airway with combined video laryngo-bronchoscopy in an awake patient with post-burn neck scar contractures.

Vigilant Fiberoptic Orotracheal Intubation in a Patient With Severe Craniofacial Trauma During the Last Morocco Earthquake

Maxillofacial trauma is prevalent, particularly among the young population, often stemming from assaults, road accidents, or sports-related mishaps. Traditional intubation methods for managing these injuries can be challenging, especially with occluso-facial fractures requiring intermaxillary blocking for dental articulation restoration. Effective management requires interdisciplinary collaboration between emergency physicians, anesthetists, and maxillofacial surgeons. Proficiency in techniques like the vigilant fiberoptic approach should be emphasized through specialized training courses. This collaborative approach ensures the best possible strategy for managing difficult airways, with input from all stakeholders including patients, students, and practitioners. In this case, we successfully conducted a rapid-sequence awake fiberoptic oral intubation on a trauma patient, during the last earthquake that hit Morocco, with severe craniofacial injuries and an unstable skull. The patient, a 40-year-old woman, presented with complex facial fractures, including hemi lefort III on the right and hemi lefort II on the left, along with minimal subarachnoid hemorrhage and frontal pneumocephalus. Due to the patient's compromised airway from diffuse facial bleeding and low oxygen saturation, we opted for awake fiberoptic intubation once immediate life-threatening issues were addressed. This approach allowed us to maintain the patient's spontaneous respirations and navigate around unstable craniofacial structures. The procedure was performed with meticulous care, considering the patient's unstable skull, and was successful without complications. Post-intubation, the patient was extubated, and her recovery was uneventful.

Pilot multicenter study to determine the utility of point-of-care ultrasound to predict difficulty of tracheal intubation using videolaryngoscopy with the McGrath™ Mac videolaryngoscope

Background

Clinical airway screening tests used to predict difficulties during airway management have low sensitivity and specificity. Point-of-care airway ultrasound has described measurements related to problems with difficult direct laryngoscopy. Nevertheless, the correlation between ultrasound parameters and videolaryngoscopy has not been published yet. The aim of this multicenter, prospective observational pilot study was to evaluate the applicability of clinical parameters and ultrasound measurements to find potential tracheal intubation difficulties when videolaryngoscopy is used.

Methods

Preoperatively, six clinical airway assessments were performed: (1) modified Mallampati score, (2) thyromental distance, (3) sternomental distance, (4) interincisal distance, (5) upper lip bite test, and (6) neck circumference. Six ultrasound parameters were measured in awake patients: (1) distance from skin to hyoid bone, (2) distance from skin to epiglottis, (3) hyomental distance in neutral head position, (4) hyomental distance in head-extended position, (5) distance from skin to the deepest part of the palate, and (6) sagittal tongue area. And finally, there was one ultrasound measure obtained in anesthetized patients, the compressed sagittal tongue area during videolaryngoscopy. The difficulty for tracheal intubation using a McGrath™ Mac videolaryngoscope, the percentage of glottic opening, and Cormack-Lehane grade were also assessed.

Results

In this cohort of 119 subjects, tongue dimensions, particularly the sagittal tongue area, showed a robust association with increased intubation difficulty using videolaryngoscopy. A multiparametric model combining the following three ultrasound variables in awake patients: (a) the distance from skin to epiglottis, (b) the distance from skin to the deepest part of the palate, and (c) the sagittal tongue area, yielded a sensitivity of 92.3%, specificity of 94.5%, positive predictive value of 82.8%, and negative predictive value of 97.8% (p < 0.001).

Conclusion

Point-of-care airway ultrasound emerges as a more useful tool compared to traditional clinical scales to anticipate possible challenges during videolaryngoscopic intubation.

Comparison of the effects of paratracheal pressure and cricoid pressure on placement of the i-gel® supraglottic airway: a randomized clinical trial

PURPOSE

Anesthesiologists can use supraglottic airway devices as a rescue technique for failed intubation even in patients with an increased risk of gastric regurgitation. In this randomized study, we aimed to evaluate the effects of cricoid pressure and paratracheal pressure on placement of the i-gel® (Intersurgical Ltd., Wokingham, Berkshire, UK).

METHODS

After induction of anesthesia in 76 adult patients, we inserted the i-gel under paratracheal or cricoid pressure, and assessed the success rate of i-gel insertion, resistance during insertion, time required for insertion, accuracy of the insertion location, tidal volumes, and peak inspiratory pressure with or without each maneuver after i-gel insertion.

RESULTS

The overall success rate of insertion was significantly higher under paratracheal pressure than under cricoid pressure (36/38 [95%] vs 27/38 [71%], respectively; difference, 24%; 95% confidence interval [CI], 8 to 40; P = 0.006]. Resistance during insertion was significantly lower under paratracheal pressure than under cricoid pressure (P < 0.001). The time required for insertion was significantly shorter under paratracheal pressure than under cricoid pressure (median [interquartile range], 18 [15-23] sec vs 28 [22-38] sec, respectively; difference in medians, -10; 95% CI, -18 to -4; P < 0.001). Fibreoptic examination of the anatomical alignment of the i-gel in the larynx revealed no significant difference in the accuracy of the insertion location between the two maneuvers (P = 0.31). The differences in tidal volume and peak inspiratory pressure with or without the maneuvers were significantly lower with paratracheal pressure than with cricoid pressure (P = 0.003, respectively).

CONCLUSIONS

Insertion of the i-gel supraglottic airway was significantly more successful, easier, and faster while applying paratracheal pressure than cricoid pressure.

STUDY REGISTRATION

ClinicalTrials.gov (NCT05377346); first submitted 11 May 2022.

Correlating Simulation Training and Assessment With Clinical Performance: A Feasibility Study

OBJECTIVE

Simulation education and assessment are increasingly used in prehospital curriculums. The objective of this study was to assess the challenges and feasibility of correlating evaluation data from an airway management simulation assessment with clinical performance.

METHODS

This study was undertaken in Ontario, the most populous province in Canada, where 13 bases are distributed in geographically diverse areas, from urban to rural and remote locations. This is a retrospective cohort study of paramedics who had completed simulation education and assessment in rapid sequence intubation. Logistic regression was used to assess for correlation between assessment scores (ie, the global score and the overall score and the definitive airway sans hypoxia/hypotension on the first attempt [DASH-1A] success in the field).

RESULTS

DASH-1A success when grouped by base varied from 25% to 100%. The odds of DASH-1A success increased for paramedics who had a higher overall score (odds ratio [OR]: 1.03; 95% confidence interval [CI], 0.96-1.11) and for paramedics who had a higher global rating (OR: 1.27; CI, 0.73-2.21) when accounting for base intubation frequency. The odds of DASH-1A success increased for paramedics who had a higher overall score (OR: 1.01; CI, 0.93-1.09) and decreased for paramedics who had a higher global rating (OR: 0.96; CI, 0.47-1.96) when accounting for base geography.

CONCLUSION

Although this study lacked a sample size large enough to draw conclusions, it provides a foundation and areas to improve in future work exploring the relationship between simulation assessments and clinical performance.

Anesthetic Management of a Patient with Madelung's Disease Presenting with a Giant Cervical Lipoma: A Case Report

Madelung's disease is characterized by the presence of multiple symmetric and nonencapsulated facial, neck, and upper trunk lipomas. Depending on the location and size of lipomas, there may be concerns for difficult airway management and cardiovascular collapse. We present the anesthetic management case of a patient with cervical and mediastinal lipomas who underwent elective cervical lipoma resection.

Innovations to Improve Lung Isolation Training for Thoracic Anesthesia: A Narrative Review

A double-lumen tube or bronchial blocker positioning using flexible bronchoscopy for lung isolation and one-lung ventilation requires specific technical competencies. Training to acquire and retain such skills remains a challenge in thoracic anesthesia. Recent technological and innovative developments in the field of simulation have opened up exciting new horizons and possibilities. In this narrative review, we examine the latest development of existing training modalities while investigating, in particular, the use of emergent techniques such as virtual reality bronchoscopy simulation, virtual airway endoscopy, or the preoperative 3D printing of airways. The goal of this article is, therefore, to summarize the role of existing and future applications of training models/simulators and virtual reality simulators for training flexible bronchoscopy and lung isolation for thoracic anesthesia.

High-flow nasal oxygenation versus face mask oxygenation for preoxygenation in patients undergoing double-lumen endobronchial intubation: protocol of a randomised controlled trial

INTRODUCTION

With the growing emphasis on swift recovery, minimally invasive thoracic surgery has advanced significantly. Video-assisted thoracoscopic surgery (VATS) has seen rapid development, and the double-lumen tube (DLT) remains the most dependable method for tracheal intubation in VATS. However, hypoxaemia during DLT intubation poses a threat to the perioperative safety of thoracic surgery patients. Recently, transnasal high-flow nasal oxygen (HFNO) has shown promise in anaesthesia, particularly in handling short-duration hypoxic airway emergencies. Yet, its application in the perioperative period for patients undergoing pulmonary surgery with compromised cardiopulmonary function lacks evidence, and there are limited reliable clinical data.

METHODS AND ANALYSIS

A prospective, randomised, controlled, single-blind design will be employed in this study. 112 patients aged 18-60 years undergoing elective VATS-assisted pulmonary surgery will be enrolled and randomly divided into two groups: the nasal high-flow oxygen group (H group) and the traditional mask transnasal oxygen group (M group) in a 1:1 ratio. HFNO will be used during DLT intubation for the prevention of asphyxia in group H, while conventional intubation procedures will be followed by group M. Comparison will be made between the two groups in terms of minimum oxygen saturation during intubation, hypoxaemia incidence during intubation, perioperative complications and postoperative hospital days.

ETHICS AND DISSEMINATION

Approval for this study has been granted by the local ethics committee at Shenzhen Second People's Hospital. The trial results will be disseminated through peer-reviewed journals and scientific conferences.

TRIAL REGISTRATION NUMBER

NCT05666908.

Awake tracheal intubation in routine airway management: A retrospective analysis in a tertiary centre

INTRODUCTION

While awake tracheal intubation (ATI) is regarded as the gold standard for difficult airway management according to current guidelines, there seems to be a reluctance in its application. This retrospective cohort study, conducted at a German tertiary hospital over a 2-year period, aimed to demonstrate that integrating awake tracheal intubation using flexible bronchoscopy (ATI:FB) into routine airway management makes it a successful and safe approach.

MATERIALS AND METHODS

In 2019 and 2020, records from the data acquisition system (DAQ) and archived anesthesia records were screened to evaluate the specifics of ATI:FB procedures, focusing on overall success and safety. Analysis included complications, time required for ATI:FB, and potential influencing factors such as patient characteristics, indication, medical/operative specialty, sedation technique, route and experience of anesthesiologist. Logistic regression assessed the impact of various variables on occurrence of complications and linear regression, with log(time) as the dependent variable, evaluated median time required to perform ATI:FB.

RESULTS

ATI:FB constituted 4.3 % (n = 1,911) of all airway management procedures, predominantly observed in dental, oral, and maxillofacial surgery (46.5 %) and otorhinolaryngology (38.4 %). The success rate for ATI:FB was notably high at 99.6 %, with only 5.4 % of cases experiencing complications, including technical issues, agitation, and visibility obstruction due to mucous secretion. Complication risk was influenced by the medical specialty and the experience of the anesthesiologist. A strong effect was observed in otorhinolaryngology (OR = 4.54, 95 % CI [1.64; 14.06]). The median time required for ATI:FB was 16 minutes (IQR: 11 to 23), with factors such as indication (p < 0.0001), experience of anesthesiologist (p < 0.0001), sedation technique (p = 0.0408), priority of the procedure (p = 0.0134), and medical/operative specialty (p < 0.0001) affecting the duration. The median time required for ATI:FB differed significantly based on the experience of the anesthesiologist (p < 0.0001).

CONCLUSION

ATI:FB proves successful and safe, with low complications and manageable procedural time. Experience of the anesthesiologist is a modifiable factor enhancing safety, emphasizing the need for ATI:FB integration into routine airway management.

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.

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 I

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 two 3D scanning software to identify facial features: a prospective instrument to predict difficult airway

BACKGROUND

Clinical airway assessment has limited predictive ability to anticipate difficult airway. Three-dimensional (3D) technologies have emerged in medicine as valuable tools in different settings including innovation and surgical planning. Three-dimensional facial scanning could add value to clinical measurements and two-dimensional models to assess the airway. However, commonly used high-fidelity scans are expensive. This study aims to compare the accuracy of the measurements made by the Scandy Pro app as a cost-effective alternative to high-fidelity scans made by the Artec Space Spider. We also aim to evaluate the interobserver variability for the measurements performed with Scandy Pro.

MATERIALS AND METHODS

We conducted a cross-sectional, comparison study on 10 healthy volunteers. Four observers measured 720 distances and 400 using both Scandy Pro and Artec Space Spider facial scans. Wilcoxon test was used for group-group comparison.

RESULTS

Comparison of both instruments showed no difference in angle or distance measurements. The percentage error (measurement difference between the two devices) exhibited by one of the observers was significantly different compared with the other three observers; however, the magnitude of this individual deviation did not affect the overall percentage error. The overall error for Scandy Pro was 5.5% (3.9% and 6.7% for angles and distances, respectively).

CONCLUSION

Three-dimensional facial scanning with Scandy Pro is an accurate tool that can be a cost-effective alternative to high-fidelity scans produced by the Artec Space Spider.

Oropharyngeal Hemorrhage and Difficult Airway Management: A Decision Not to Intubate

BACKGROUND

Bleeding in the upper airways is an important cause of airway-related death. A higher incidence of airway management failure and complications after intubation attempts in the emergency department (ED) had been suggested. Airway management of patients with active oropharyngeal hemorrhage may be challenging, leading the clinician to modify the approach.

CASE REPORT

A 57-year-old woman presented to the ED with oropharyngeal hemorrhage after an extensive invasive dental procedure. She was on long-term warfarin therapy due to aortic and mitral valve replacement, which she suspended 5 days prior and restarted the day after the procedure. Besides the active bleeding, swelling, and hematoma of the face, the patient had other signs of "difficult airway," so there were serious questions on when and how to manage the airway. Several strategies to address the airway were considered, the main point being an early versus later intubation. As the patient remained clinically stable, she was conservatively managed with local hemostasis and coagulopathy reversal. The patient was transferred to the intensive care unit, where she remained stable and was successfully discharged after restart on warfarin. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: When faced with an oropharyngeal hemorrhage, emergency physicians may be compelled to secure and protect the airway. This could be achieved by planning several strategies. Nevertheless, in selected patients, and considering the circumstances, not addressing the airway is a reasonable and justifiable alternative.

Integration of simulation-based education in anaesthesiology specialist training: Synthesis of results from an Utstein Meeting

BACKGROUND

Despite its importance in education and patient safety, simulation-based education and training (SBET) is only partially or poorly implemented in many countries, including most European countries. The provision of a roadmap may contribute to the development of SBET for the training of anaesthesiologists.

OBJECTIVE

To develop a global agenda for the integration of simulation into anaesthesiology specialist training; identify the learning domains and objectives that are best achieved through SBET; and to provide examples of simulation modalities and evaluation methods for these learning objectives.

DESIGN

Utstein-style meeting where an expert consensus was reached after a series of short plenary presentations followed by small group workshops, underpinned by Kern's six-step theoretical approach to curriculum development.

SETTING

Utstein-style collaborative meeting.

PARTICIPANTS

Twenty-five participants from 22 countries, including 23 international experts in simulation and two anaesthesia trainees.

RESULTS

We identified the following ten domains of expertise for which SBET should be used to achieve the desired training outcomes: boot camp/initial training, airway management, regional anaesthesia, point of care ultrasound, obstetrics anaesthesia, paediatric anaesthesia, trauma, intensive care, critical events in our specialty, and professionalism and difficult conversations. For each domain, we developed a course template that defines the learning objectives, instructional strategies (including simulation modalities and simulator types), and assessment methods. Aspects related to the practical implementation, barriers and facilitators of this program were also identified and discussed.

CONCLUSIONS

We successfully developed a comprehensive agenda to facilitate the integration of SBET into anaesthesiology specialist training. The combination of the six-step approach with the Utstein-style process proved to be extremely valuable in supporting content validity and representativeness. These results may facilitate the implementation and use of SBET in several countries.

TRIAL REGISTRATION

Not applicable.

Hyperangulated blades or direct epiglottis lifting to optimize glottis visualization in difficult Macintosh videolaryngoscopy: a non-inferiority analysis of a prospective observational study

Purpose

It is unknown if direct epiglottis lifting or conversion to hyperangulated videolaryngoscopes, or even direct epiglottis lifting with hyperangulated videolaryngoscopes, may optimize glottis visualization in situations where Macintosh videolaryngoscopy turns out to be more difficult than expected. This study aims to determine if the percentage of glottic opening (POGO) improvement achieved by direct epiglottis lifting is non-inferior to the one accomplished by a conversion to hyperangulated videolaryngoscopy in these situations.

Methods

One or more optimization techniques were applied in 129 difficult Macintosh videolaryngoscopy cases in this secondary analysis of a prospective observational study. Stored videos were reviewed by at least three independent observers who assessed the POGO and six glottis view grades. A linear mixed regression and a linear regression model were fitted. Estimated marginal means were used to analyze differences between optimization maneuvers.

Results

In this study, 163 optimization maneuvers (77 direct epiglottis lifting, 57 hyperangulated videolaryngoscopy and 29 direct epiglottis lifting with a hyperangulated videolaryngoscope) were applied exclusively or sequentially. Vocal cords were not visible in 91.5% of the cases with Macintosh videolaryngoscopy, 24.7% with direct epiglottis lifting, 36.8% with hyperangulated videolaryngoscopy and 0% with direct lifting with a hyperangulated videolaryngoscope. Conversion to direct epiglottis lifting improved POGO (mean + 49.7%; 95% confidence interval [CI] 41.4 to 58.0; p < 0.001) and glottis view (mean + 2.2 grades; 95% CI 1.9 to 2.5; p < 0.001). Conversion to hyperangulated videolaryngoscopy improved POGO (mean + 43.7%; 95% CI 34.1 to 53.3; p < 0.001) and glottis view (mean + 1.9 grades; 95% CI 1.6 to 2.2; p < 0.001). The difference in POGO improvement between conversion to direct epiglottis lifting and conversion to hyperangulated videolaryngoscopy is: mean 6.0%; 95% CI -6.5-18.5%; hence non-inferiority was confirmed.

Conclusion

When Macintosh videolaryngoscopy turned out to be difficult, glottis exposure with direct epiglottis lifting was non-inferior to the one gathered by conversion to hyperangulated videolaryngoscopy. A combination of both maneuvers yields the best result.

Clinical trial registration

ClinicalTrials.gov, NCT03950934.

Vie Scope® versus videolaryngoscopy in expected difficult airways: a randomized controlled trial

PURPOSE

The management of patients with an anticipated difficult airway remains challenging. We evaluated laryngeal visualization with the recently introduced Vie Scope® as a straight blade laryngoscope consisting of an illuminated tube necessitating bougie-facilitated intubation vs Macintosh videolaryngoscopy.

METHODS

We conducted a prospective randomized controlled noninferiority trial. Patients undergoing elective ear, nose, and throat or oral and maxillofacial surgery with an anticipated difficult airway were randomized 1:1 to receive tracheal intubation with the Vie Scope or Macintosh videolaryngoscope (C-MAC®). The primary outcome measure was laryngeal visualization by the percentage of glottis opening (POGO) scale. Secondary outcome measures were the time to successful intubation (TTI) and first-attempt and overall success rates.

RESULTS

We included two sets of 29 patients in our analysis. For visualization, the Vie Scope was noninferior to videolaryngoscopy (VL) with mean (standard deviation [SD]) POGO scores of 71 (31)% vs 64 (30)% in the VL group [difference in means, 7 (8)%; 95% confidence interval, -9 to 23; P = 0.38]. Mean (SD) TTI was 125 (129) sec in the Vie Scope and 51 (36) sec in the VL group (difference in means, 75 sec; 95% confidence interval, 25 to 124; P = 0.005). The first-attempt and overall success rates were 22/29 (76%) and 27/29 (93%) in both groups. Two patients per group were switched to a different device. Four accidental esophageal intubations occurred in the Vie Scope group, these were presumably due to bougie misplacement.

CONCLUSION

Visualization with the Vie Scope was noninferior to VL in patients with an anticipated difficult airway, but TTI was longer in the Vie Scope group.

STUDY REGISTRATION

ClinicalTrials.gov (NCT05044416); registered 5 September 2021.

Upper airway angle and glottic height: a prospective cohort to evaluate two new features for airway prediction

BACKGROUND

Predicting difficult direct laryngoscopies remains challenging and improvements are needed in preoperative airway assessment. We conceived two new tests (the upper airway angle and the glottic height) and assessed their association with difficult direct laryngoscopies as well as their predictive performance.

METHODS

A prospective cohort was conducted with 211 patients undergoing general anesthesia for surgical procedures. We assessed the association between difficult laryngoscopies and modified Mallampati Test (MMT), Upper Lip Bite Test (ULBT), Mandibular Length (ML), Neck Circumference (NC), Mouth Opening (MO), Sternomental Distance (SMD), Thyromental Distance (TMD), Upper Airway Angle (UAA), and Glottic Height (GH). We also estimated their predictive values.

RESULTS

Difficult laryngoscopy was presented by 12 patients (5.7%). Six tests were significantly associated with difficult laryngoscopies and their area under the ROC curve, and 95% CIs were as follows: UAA = 88.82 (81.86-95.78); GH = 86.43 (72.67-100); ML = 83.75 (72.77-94.74); NC = 79.17 (64.98-93.36); MO = 65.58 (45.13-86.02); and MMT = 77.89 (68.37-87.41).

CONCLUSION

We have found two new features (the UAA and the GH) to be significantly associated with the occurrence of difficult direct laryngoscopies. They also presented the best predictive performance amongst the nine evaluated tests in our cohort of patients. We cannot ensure, however, these tests to be superior to other regularly used bedside tests based on our estimated 95% CIs.

Anesthetic challenges in difficult airway in a patient with maxillary carcinoma: A case report

Airway management in patients with maxillary carcinoma presents unique challenges. To ensure safety, a tailored and collaborative approach is essential. This is a case where anesthetic plan of awake fiberoptic oral endotracheal intubation was chosen.

Glidescope Video Laryngoscopy in Patients with Severely Restricted Mouth Opening-A Pilot Study

BACKGROUND

An inter-incisor gap <3 cm is considered critical for videolaryngoscopy. It is unknown if new generation GlideScope Spectrum™ videolaryngoscopes with low-profile hyperangulated blades might facilitate safe tracheal intubation in these patients. This prospective pilot study aims to evaluate feasibility and safety of GlideScopeTM videolaryngoscopes in severely restricted mouth opening.

METHODS

Feasibility study in 30 adults with inter-incisor gaps between 1.0 and 3.0 cm scheduled for ENT or maxillofacial surgery. Individuals at risk for aspiration or rapid desaturation were excluded.

RESULTS

The mean mouth opening was 2.2 ± 0.5 cm (range 1.1-3.0 cm). First attempt success rate was 90% and overall success was 100%. A glottis view grade 1 or 2a was achieved in all patients. Nasotracheal intubation was particularly difficult if Magill forceps were required (n = 4). Intubation time differed between orotracheal (n = 9; 33 (25; 39) s) and nasotracheal (n = 21; 55 (38; 94) s); p = 0.049 intubations. The airway operator's subjective ratings on visual analogue scales (0-100) revealed that tube placement was more difficult in individuals with an inter-incisor gap <2.0 cm (n = 10; 35 (29; 54)) versus ≥2.0 cm (n = 20; 20 (10; 30)), p = 0.007, while quality of glottis exposure did not differ.

CONCLUSIONS

GlidescopeTM videolaryngoscopy is feasible and safe in patients with severely restricted mouth opening if given limitations are respected.

Developing a magnetic POCUS-guided bronchoscope for patients with suspected difficult endotracheal intubation in a general tertiary hospital: protocol for a randomised controlled study

INTRODUCTION

Endotracheal intubation (ETI) is a crucial but risky procedure, especially among patients suspected of difficult endotracheal intubation (DTI). Bronchoscope, as an improved technique commonly used in DTI, might encounter visualisation difficulties. The magnetic point-of-care ultrasound (MGPOCUS) provides a novel visualisation from the outside and enables estimation of the relative position and trajectory of the bronchoscope. The purpose of the study was to evaluate the efficiency of MGPOCUS-guided bronchoscopy, including the time required for successful ETI, the first attempt and overall success rate, the number of attempts, complications, and satisfaction with the visualization of the procedures.

METHODS AND ANALYSIS

The study is a randomised, parallel-group, single-blinded, single-centre study. Participants (n=108) will be recruited by the primary anaesthesiologist and randomised to groups of ETI with bronchoscope or MGPOCUS-guided bronchoscope. The primary outcome is the time taken to the first-attempt success ETI. Secondary outcomes include procedure time, the first-attempt and overall success, complications, and satisfaction of visualisation. Cox regression with Bonferroni correction and linear mixed regression will be used to analyse the outcomes.

ETHICS AND DISSEMINATION

The trial protocol was approved by the ethics committees at the Peking Union Medical College Hospital (Institutional Review Board #ZS-3428). Findings will be disseminated through conference presentations and peer-reviewed journals.

TRIAL REGISTRATION NUMBER

NCT05647174.

Ultrasound-Guided Glossopharyngeal Nerve Block for an Awake Intubation in a Patient Predicted to Have a Difficult Airway: A Case Report

A peripheral nerve block may be used to improve patient tolerance of awake intubation. During an awake intubation, the glossopharyngeal, superior laryngeal, and recurrent laryngeal nerves can mediate discomfort, pain, cough, glottic closure, and gag reflexes. We describe the use of ultrasound-guided superior laryngeal, recurrent laryngeal, and glossopharyngeal nerve blocks to facilitate awake intubation in a patient predicted to have a difficult airway. The glossopharyngeal nerve block was performed via the parapharyngeal space approach targeting the distal glossopharyngeal nerve. This procedure resulted in an uneventful awake intubation.

A randomized controlled trial comparing three supraglottic airway devices used as a conduit to facilitate tracheal intubation with flexible bronchoscopy

PURPOSE

Once difficult ventilation and intubation are declared, guidelines suggest the use of a supraglottic airway (SGA) as a rescue device to ventilate and, if oxygenation is restored, subsequently as an intubation conduit. Nevertheless, few trials have formally studied recent SGA devices in patients. Our objective was to compare the efficacy of three second-generation SGA devices as conduits for bronchoscopy-guided endotracheal intubation.

METHODS

In this prospective, single-blinded three-arm randomized controlled trial, patients with an American Society of Anesthesiologists Physical Status of I-III undergoing general anesthesia were randomized to bronchoscopy-guided endotracheal intubation using AuraGain™, Air-Q® Blocker, or i-gel® devices. We excluded patients with contraindications to an SGA or drugs and who were pregnant or had a neck, spine, or respiratory anomaly. The primary outcome was intubation time, measured from SGA circuit disconnection to CO2 measurement. Secondary outcomes included ease, time, and success of SGA insertion; success of intubation on first attempt; overall intubation success; number of attempts to intubate; ease of intubation; and ease of SGA removals.

RESULTS

One hundred and fifty patients were enrolled from March 2017 to January 2018. Median intubation times were similar across the three groups (Air-Q Blocker, 44 sec; AuraGain, 45 sec; i-gel, 36 sec; P = 0.08). The i-gel was faster to insert (i-gel: 10 sec; Air-Q Blocker, 16 sec; AuraGain, 16 sec; P < 0.001) and easier to insert (Air-Q Blocker vs i-gel, P = 0.001; AuraGain vs i-gel, P = 0.002). Success of SGA insertion, success of intubation, and number of attempts were similar. The Air-Q Blocker was easier to remove than the i-gel (P < 0.001).

CONCLUSION

All three second-generation SGA devices performed similarly regarding intubation. Despite minor benefits of the i-gel, clinicians should select their SGA based on clinical experience.

STUDY REGISTRATION

ClinicalTrials.gov (NCT02975466); registered on 29 November 2016.

Airway nerve blocks for awake tracheal intubation: A meta-analysis of randomized control trials and trial sequential analysis

STUDY OBJECTIVE

This systematic review and meta-analysis aimed to assess the superiority of airway nerve blocks versus airway anesthesia without nerve blocks for awake tracheal intubation (ATI).

DESIGN

Systematic review and meta-analysis of randomized controlled trials (RCTs).

SETTING

All studies that assessed the superiority of airway anesthesia technique for awake tracheal intubation were searched in PubMed, Web of Science, Cochrane Library, Ovid Medline, Embase and Chinese databases (including China National Knowledge Infrastructure, Wanfang database, and VIP databases) and trial registry databases from their inception to December 2022.

PATIENTS

Adult patients included in randomized controlled trials comparing airway anesthesia with or without airway nerve blocks for ATI.

INTERVENTIONS

Airway nerve (including superior laryngeal nerve, glossopharyngeal nerve, or recurrent laryngeal nerve) blocks for ATI.

MEASUREMENTS

The primary outcome was the intubation time. Secondary outcomes were quality of intubating conditions (including patient reaction to placement of the flexible scope and tracheal tube, coughing and gagging, and patient satisfaction) and overall complications during ATI.

MAIN RESULTS

Fourteen articles with 658 patients were identified for analysis. When compared with airway anesthesia without nerve blocks, airway nerve blocks significantly reduced intubation time (standardized mean difference [SMD] -2.57, 95% CI -3.59- -1.56, p < 0.00001), improved anesthesia quality of ATI with higher no reaction to placement of the flexible scope and tracheal tube (relative risk [RR] 9.87; 95% CI 4.10-23.75, p < 0.00001), lower cough or gag reflex during intubation (RR 0.35, 95% CI 0.27-0.46, p < 0.00001), higher excellent patient satisfaction rate (RR 1.88, 95% CI 1.05-3.34, p = 0.03), and lower overall complications (RR 0.29, 95% CI 0.19-0.45, p < 0.00001). The overall quality of evidence was moderate.

CONCLUSIONS

Based on current published evidence, airway nerve blocks provide better airway anesthesia quality for ATI with a shorter intubation time, better intubation conditions including higher no reaction to placement of the flexible scope and tracheal tube, lower cough or gag reflex during intubation, higher excellent patient satisfaction, and lower overall complications.

A Randomized Comparison of Intravenous Versus Nebulized Routes for Administering Dexmedetomidine and Ketamine Combination to Facilitate Awake Fibreoptic Intubation

Introduction Awake fibreoptic intubation is a technique used to secure the airway of patients who are having predicted difficult intubation. We compared two routes, intravenous and nebulized, for administering a combination of ketamine and dexmedetomidine to patients requiring sedation for fibreoptic intubation. Methods and materials After approval of the institutional ethics committee, 64 patients between 18 and 60 years belonging to the American Society of Anesthesiologists physical status I or II and having predicted difficult airway were randomized to receive study medications through either intravenous (group I, n = 32) or nebulized (group N, n = 32) routes. Group I patients were given a combination of ketamine and dexmedetomidine through intravenous route. Group N patients were nebulized with a combination of ketamine and dexmedetomidine. The time required for awake fiberoptic intubation was the primary outcome variable. In addition, sedation score, cough severity, patient tolerance, intubating condition, hemodynamic changes, recall of events and discomfort during intubation, and any adverse events in the perioperative period were also compared. Results Compared to group N, the time needed to intubate the patients was significantly less in group I (75.69 ± 10.83 versus 49.19 ± 3.60 seconds, p < 0.001). Observer assessment sedation/alertness score (p < 0.001), cough severity (p < 0.001), patient tolerance (p < 0.001), and intubating condition (p = 0.001) were statistically significant, all conditions being better in group I. Patient discomfort and recall of the procedure were statistically similar between the groups. Conclusions The efficacy of a combination of dexmedetomidine and ketamine through the intravenous route is better than the nebulized route for patients undergoing awake fibreoptic intubation.

The anesthetic consideration of a gravid patient with osteogenesis imperfecta undergoing cesarean section: A case report

Osteogenesis imperfecta (OI) is a rare disorder of bone fragility. Gravid patients with OI usually need cesarean and may present multiple challenges. We present a case of an OI patient with severe scoliosis and an anticipated difficult airway undergoing cesarean section, with details on perioperative assessment and strategy of anesthesia.

PREOPERATIVE SINGLE ANTHROPOMETRIC SCREENING TESTS OF DIFFICULT FACE MASK VENTILATION AND DIFFICULT DIRECT LARYNGOSCOPY INTUBATION IN PATIENTS UNDERGOING OTORHINOLARYNGOLOGICAL SURGERY: A PROSPECTIVE, OBSERVATIONAL, SINGLE CENTER STUDY

The aim of this study was to assess preoperative airway history data and single anthropometric screening tests of difficult face mask ventilation (FMV) and difficult direct laryngoscopy intubation (DLI) in otorhinolaryngological surgery. Final analysis included 62 patients aged ≥14 years undergoing elective surgery with endotracheal intubation at a single center during a one-month period. Data on difficult intubation history, airway symptoms and pathology related to difficult airway were prospectively collected. Han scoring classification of FMV and Intubation Difficulty Score (IDS) were used. There were 14 (22.6%) patients with a history of current airway tumors or abscesses. Only two (3.2%) patients were preoperatively evaluated as anticipated difficult airway. Both were slightly difficult to ventilate and scored IDS 5 and IDS 8. FMV was graded as easy in 50 (80.5%), slightly difficult in 10 (16.1%) and difficult in 2 (3.2%) cases. There were 29 (46.78%) slightly difficult DLIs and one (1.6%) case of difficult DLI. The study confirmed clinically relevant incidence of difficulties with FMV and DLI in otorhinolaryngologic surgery patients. However, there should be stronger evidence to identify a single preoperative variable predicting difficult airway.

Airway ultrasound for patients anticipated to have a difficult airway: Perspective for personalized medicine

Airway ultrasound allows for precise airway evaluation, particularly for assessing the difficult airway and the potential for front of neck access. Many studies have shown that identification of the cricothyroid membrane by airway ultrasound is more accurate than digital palpation. However, no reports to date have provided clinical evidence that ultrasound identification of the cricothyroid membrane increases the success rate of cricothyroidotomy. This is a narrative review which describes patients with difficult airways for whom airway ultrasound may have been useful for clinical decision making. The role of airway ultrasound for the evaluation of difficult airways is summarized and an approach to the use of ultrasound for airway management is proposed. The goal of this review is to present practical applications of airway ultrasound for patients predicted to have a difficult airway and who undergo cricothyroidotomy.

An Approach to Improve the Effectiveness of the Video-Assisted Intubating Stylet Technique for Tracheal Intubation: A Case Series Report

Direct laryngoscopy and videolaryngoscopy are currently the dominant tools for endotracheal intubation. However, the video-assisted intubating stylet, a type of videolaryngoscopy, has been shown to offer some advantages over these tools, such as rapid intubation time, high first-attempt success rates, less airway stimulation, and high subjective satisfaction. On the other hand, this optical intubating technique also has some technical limitations that need to be addressed, including camera lens fogging, airway path disorientation, and obscured visibility due to secretions. In this clinical report, we describe an approach that improves the visibility of the glottis by introducing a suctioning catheter into the nasopharyngeal airway to enhance the efficiency and accuracy of using the intubating stylet technique for 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.

Preventing unrecognised oesophageal intubation

Major harm from unrecognised oesophageal intubation continues, despite the 2018 Royal College of Anaesthetists' 'no trace, wrong place' campaign. It is likely that publicly reported cases represent a fraction of real occurrences. This article summarises a 2022 consensus guideline on the prevention of unrecognised oesophageal intubation from the Project for Universal Management of Airway and international airway societies. The guideline is written for all airway operators and assistants, in any clinical setting, and readers are advised to deepen their understanding by studying the original guideline. The recommendations include how to avoid and recognise oesophageal intubation as well as a set of logical actions to take when it is a plausible possibility, even if it is not suspected. The guideline emphasises the importance of videolaryngoscopy, capnography and oxygen saturation monitoring for all tracheal intubations, wherever performed. It introduces the concept of sustained exhaled carbon dioxide, which is central to identifying oesophageal intubation, and acting to prevent progression to unrecognised oesophageal intubation. In the absence of sustained exhaled carbon dioxide, the default action is to remove the tube. This will mean some tracheal placed tubes are removed but based on a risk-benefit analysis, this is desirable. The tube should only be left in place if there is clear danger in removing it and in this event, its position should be confirmed, using repeat videolaryngoscopy plus one other of bronchoscopy, skilled ultrasound or use of an oesophageal detector device. The importance of human factors is underlined; for instance, the value of a shared and vocalised report of videolaryngoscopy view and trained assistants working with the operator to confirm whether the criteria for sustained exhaled carbon dioxide are met, to minimise error and improve team working.

Incidence of rescue surgical airways after attempted orotracheal intubation in the emergency department: A National Emergency Airway Registry (NEAR) Study

BACKGROUND

Cricothyrotomy is a critical technique for rescue of the failed airway in the emergency department (ED). Since the adoption of video laryngoscopy, the incidence of rescue surgical airways (those performed after at least one unsuccessful orotracheal or nasotracheal intubation attempt), and the circumstances where they are attempted, has not been characterized.

OBJECTIVE

We report the incidence and indications for rescue surgical airways using a multicenter observational registry.

METHODS

We performed a retrospective analysis of rescue surgical airways in subjects ≥14 years of age. We describe patient, clinician, airway management, and outcome variables.

RESULTS

Of 19,071 subjects in NEAR, 17,720 (92.9%) were ≥14 years old with at least one initial orotracheal or nasotracheal intubation attempt, 49 received a rescue surgical airway attempt, an incidence of 2.8 cases per 1000 (0.28% [95% confidence interval 0.21 to 0.37]). The median number of airway attempts prior to rescue surgical airways was 2 (interquartile range 1, 2). Twenty-five were in trauma victims (51.0% [36.5 to 65.4]), with neck trauma being the most common traumatic indication (n = 7, 14.3% [6.4 to 27.9]).

CONCLUSION

Rescue surgical airways occurred infrequently in the ED (0.28% [0.21 to 0.37]), with approximately half performed due to a trauma indication. These results may have implications for surgical airway skill acquisition, maintenance, and experience.

Airway Management for Penetrating Neck Trauma: A Case Report

Penetrating neck injuries comprise 5-10% of traumatic injuries in adults and can cause immediate life-threatening compromise. Performing awake fibreoptic intubation in cooperative patients when airway management is not time critical has been suggested as a method of securing these potentially complicated airways. We report a case of a male in his 20s who presented to the emergency service with neck trauma following a bicycle road accident. With the exception of a wound in the neck region, there were no alarming distress signs or symptoms of airway endangerment. Imagiological evaluation revealed a rupture of the right lateral tracheal wall. He was referred for urgent surgery. We performed intubation with video laryngoscopy assisted by a neck surgery team, keeping the patient breathing spontaneously and under deep sedation. After advancing the tube through the vocal cords, the surgeon explored the cervical wound, guiding the tube through the trachea. Keeping spontaneous ventilation and advancing the tracheal tube beyond the lesion under visualization is essential when managing a traumatized airway. Tracheal intubation using video laryngoscopy, assisted by a neck surgeon guiding the tube, and avoiding creation of a false passage can be a safe alternative to fibreoptic intubation in selected cases of tracheal laceration.

The incidence of awake tracheal intubation in anesthetic practice is decreasing: a historical cohort study of the years 2014-2020 at a single tertiary care institution

PURPOSE

Awake tracheal intubation (ATI) is recommended in airway management guidelines when significant difficulty is predicted with airway management. Use of the technique may be declining, which may have implications for patient safety or for skills acquisition and maintenance. This historical cohort database study sought to determine if the use of ATI was decreasing in our adult tertiary care center.

METHODS

With institutional research ethics board approval, we queried our anesthesia information management system for cases with ATI descriptors for each year from 2014 to 2020. Records of the retrieved cases were independently reviewed by all three authors to verify they met inclusion criteria for the ATI cohort prior to analysis for the primary outcome. Secondary outcome measures included airway device and route used for ATI, first attempt and ultimate success rates, and reported adverse issues recorded in cases of failed ATI or those requiring more than one attempt.

RESULTS

A total of 692 cases of ATI were identified between 2014 and 2020. There was a statistically significant decrease in yearly ATIs over the seven-year study period (Chi square goodness of fit, P < 0.001), with ATI use decreasing by about 50%. First attempt success was significantly greater with use of flexible bronchoscopy vs video laryngoscopy to facilitate ATI (84% vs 60%; P < 0.001), while there was no difference in first attempt success with the oral vs nasal route (82% vs 82%; P = 1.0).

CONCLUSION

In this single-center historical cohort study, the use of ATI decreased significantly from 2014 to 2020. Whether this decrease will result in morbidity or mortality related to airway management is currently unclear. Regardless, it has implications for training opportunities and maintenance of competence in performing the procedure.

Application of "twelve-step" approach based on SEEKflex for difficult awake tracheal intubation in patients with cervical spinal tumor

Difficult airway always occurs in patients with cervical spinal tumor. Awake tracheal intubation (ATI) is usually a primary safe approach for clinical doctors in these intractable difficult airways. It is of great significance to establish specific strategies to reduce related acute airway accidents. A novel "twelve-step" approach of awake tracheal intubation based on an improved introducer (Safe Easy Endotracheal Kit-flexible, "SEEK^flex") was developed and practiced in model successfully. Patients with cervical spinal tumor in a single tertiary hospital were chosen to secure airway with this approach. Primary outcomes were safety and feasibility, defined as completion of ATI without serious adverse events, Secondary outcome was the first intubation attempt rate, total intubation time, satisfaction of patients in the whole process and relevant complications. We performed awake tracheal intubation with this approach to solve the difficult airway in five patients with cervical spinal tumor. The courses went successfully in all patients without any relevant complications. This novel "twelve-step" approach based on SEEK^flex for ATI can be considered as one of optional safe choices for difficult airway in patients with cervical spinal tumor.

Time to Renitrogenation After Maximal Denitrogenation in Healthy Volunteers in the Supine and Sitting Positions

Introduction: Prior to intubation, preoxygenation is performed to denitrogenate the lungs and create an oxygen reservoir. After oxygen is removed, it is unclear whether renitrogenation after preoxygenation occurs faster in the supine vs the sitting position. Methods: We enrolled 80 healthy volunteers who underwent two preoxygenation and loss of preoxygenation procedures (one while supine and one while sitting) via bag-valve-mask ventilation with spontaneous breathing. End-tidal oxygen (ETO2) measurements were recorded as fraction of expired oxygen prior to preoxygenation, at the time of adequate preoxygenation (ETO2 >85%), and then every five seconds after the oxygen was removed until the ETO2 values reached their recorded baseline. Results: The mean ETO2 at completion of preoxygenation was 86% (95% confidence interval 85-88%). Volunteers in both the supine and upright position lost >50% of their denitrogenation in less than 60 seconds. Within 25 seconds, all subjects had an ETO2 of <70%. Complete renitrogenation, defined as return to baseline ETO2, occurred in less than 160 seconds for all volunteers. Conclusion: Preoxygenation loss, or renitrogenation, occurred rapidly after oxygen removal and was not different in the supine and sitting positions. After maximal denitrogenation in healthy volunteers, renitrogenation occurred rapidly after oxygen removal and was not different in the supine and sitting positions.

Multidisciplinary Difficult Airway Team Characteristics, Airway Securement Success, and Clinical Outcomes: A Systematic Review

Objective:

To investigate whether implementation of a multidisciplinary airway team was associated with improvement in (1) rate of successful airway securement at first attempt; (2) time to secure airway; and (3) overall complication rate in patients with a difficult airway, as compared with usual care.

Data Sources:

Ovid Medline, Embase, Scopus, Cochrane Central, and CINAHL databases.

Review Methods:

Systematic review of literature on inpatient multidisciplinary team management of difficult airways, including all studies performed in inpatient settings, excluding studies of ventilator weaning, flight/military medicine, EXIT procedures, and simulation or educational studies. DistillerSR was used for article screening and risk of a bias assessment to evaluate article quality. Data was extracted on study design, airway team composition, patient characteristics, and clinical outcomes including airway securement, complications, and mortality.

Results:

From 5323 studies screened, 19 studies met inclusion criteria with 4675 patients. Study designs included 12 quality improvement projects, 6 cohort studies, and 1 randomized controlled trial. Four studies evaluated effect of multidisciplinary difficult airway teams on airway securement; all reported higher first attempt success rate with team approach. Three studies reported time to secure the difficult airways, all reporting swifter airway securement with team approach. The most common difficult airway complications were hypoxia, esophageal intubation, hemodynamic instability, and aspiration. Team composition varied, including otolaryngologists, anesthesiologists, intensivists, nurses, and respiratory care practitioners.

Conclusion:

Multidisciplinary difficult airway teams are associated with improved clinical outcomes compared to unstructured emergency airway management; however, studies have significant heterogeneity in team composition, algorithms for airway securement, and outcomes reported. Further evidence is necessary to define the clinical efficacy, cost-effectiveness, and best practices relating to implementing difficult airway teams in inpatient settings.

The Use of the Shikani Video-Assisted Intubating Stylet Technique in Patients with Restricted Neck Mobility

Among all the proposed predictors of difficult intubation defined by the intubation difficulty scale, head and neck movement (motility) stands out and plays as a crucial factor in determining the success rate and the degree of ease on endotracheal intubation. Aside from other airway tools (e.g., supraglottic airway devices), optical devices have been developed and applied for more than two decades and have shown their superiority to conventional direct laryngoscopes in many clinical scenarios and settings. Although awake/asleep flexible fiberoptic bronchoscopy is still the gold standard in patients with unstable cervical spines immobilized with a rigid cervical collar or a halo neck brace, videolaryngoscopy has been repeatedly demonstrated to be advantageous. In this brief report, for the first time, we present our clinical experience on the routine use of the Shikani video-assisted intubating stylet technique in patients with traumatic cervical spine injuries immobilized with a cervical stabilizer and in a patient with a stereotactic headframe for neurosurgery. Some trouble-shooting strategies for this technique are discussed. This paper demonstrates that the video-assisted intubating stylet technique is an acceptable alternative airway management method in patients with restricted or confined neck motility.