Management of Difficult Tracheal Intubation: A Closed Claims Analysis

Comparison of the modified Mallampati classification score versus the best visible Mallampati score in the prediction of difficult tracheal intubation: a single-centre prospective observational study

PURPOSE

The modified Mallampati classification is part of the preoperative airway risk assessment. Inconsistency in the way it is examined may contribute to heterogeneity in its diagnostic performance. The best visible Mallampati score could reduce interobserver heterogeneity but its diagnostic characteristics remain unknown.

METHODS

During preoperative anesthesia consultation of adult patients with a senior anesthesiologist, we compared the modified Mallampati classification score vs the best visible Mallampati score using cervical extension, tongue in, and phonation. The primary outcome was the diagnostic characteristic of the modified Mallampati classification score vs the best visible Mallampati score as predictors of difficult orotracheal intubation (more than two direct laryngoscopies or need for an alternate device). We performed a multivariable analysis to identify independent predictors of difficult orotracheal intubation in the tested cohort.

RESULTS

Difficult orotracheal intubation occurred in 77/3,243 (2.4%) patients. A best visible Mallampati score was obtained in 1,596 (49.2%) patients. Sensitivity and specificity of the modified Mallampati classification score for predicting difficult orotracheal intubation were 0.56 (95% confidence interval [CI], 0.44 to 0.66) and 0.69 (95% CI, 0.68 to 0.71), respectively. By comparison, the best visible Mallampati score was less sensitive (difference, -0.30; 95% CI, -0.19 to -0.30; P < 0.001) but more specific (difference, 0.24; 95% CI, 0.22 to -0.25; P < 0.001). In patients with difficult orotracheal intubation, 53% were incorrectly reclassified as low risk by the best visible Mallampati score.

CONCLUSION

Compared with the modified Mallampati classification score, the best visible Mallampati score decreased sensitivity for predicting difficult orotracheal intubation and falsely classified half of the patients with difficult orotracheal intubation. Taking the risks associated with difficult airways into account, our findings indicate that a careful examination of the modified Mallampati classification is required during the global preoperative airway examination.

STUDY REGISTRATION

ClinicalTrials.gov ( NCT02788253 ); 9 February 2016.

The comparison of preoxygenation methods before endotracheal intubation: a network meta-analysis of randomized trials

Background

Preoxygenation before endotracheal intubation (ETI) maintains asphyxiated oxygenation and reduces the risk of hypoxia-induced adverse events. Previous studies have compared various preoxygenation methods. However, network meta-analyses (NMAs) of the combined comparison of preoxygenation methods is still lacking.

Methods

We searched for studies published in PubMed, Embase, Web of Science, Scopus, and the Cochrane Library. Review Manager version 5.3 was used to evaluate the risk of bias. The primary outcome of this meta-analysis was low oxygen saturation (SpO2) during ETI. The secondary outcomes included SpO2 <80%, SpO2 <90%, and apnea time during ETI. NMA was performed using R 4.1.2 software gemtc packages in RStudio.

Results

A total of 15 randomized controlled trials were included in this study. Regarding the lowest SpO2, the noninvasive ventilation (NIV) with high-flow nasal cannula (HFNC) group performed better than the other groups. For SpO2 <80%, the NIV group (0.8603467) performed better than the HFNC (0.1373533) and conventional oxygen therapy (COT, 0.0023) groups, according to the surface under the cumulative ranking curve results. For SpO2 <90%, the NIV group (0.60932667) performed better than the HFNC (0.37888667) and COT (0.01178667) groups. With regard to apnea time, the HFNC group was superior to the COT group (mean difference: -50.05; 95% confidence interval: -90.01, -10.09; P = 0.01).

Conclusion

Network analysis revealed that NIV for preoxygenation achieved higher SpO2 levels than HFNC and COT and offered a more significant advantage in maintaining patient oxygenation during ETI. Patients experienced a longer apnea time after HFNC preoxygenation. The combination of NIV with HFNC proved to be significantly superior to other methods. Given the scarcity of such studies, further research is needed to evaluate its effectiveness.

Systematic review registration

identifier CRD42022346013.

Evaluation of a 12-hole clock model for improving bronchoscopic skills in simulated normal and difficult airways among anesthesia residents: A randomized controlled study

BACKGROUND

Simulation-based training is used to improve fiberoptic bronchoscopic skills for novices. We developed a nonanatomical task trainer (named 12-hole clock model) that focused on training manipulation of bronchoscopes. The aim of this study was to evaluate the training effect of this model on bronchoscopic skills and learning interests in simulated normal and difficult airways among anesthesia residents.

METHODS

Forty-three anesthesia residents without experience in bronchoscopic intubation were randomly divided into control (n = 22) and intervention groups (n = 21). All participants received standard multimedia learning and a baseline test using a normal airway manikin. Then, the control and intervention groups engaged in 60 minutes of training via a traditional airway manikin or the clock model, respectively. After training, the participants completed bronchoscopic performance assessments in simulated normal and difficult airways, as well as an electronic questionnaire related to the course.

RESULTS

During training, the total hands-on time of bronchoscopic practice recorded by trainees' themselves was longer in the intervention group than in the control group (1568 ± 478 seconds vs 497 ± 172 s, P < .0001). Posttraining, the time required to visualize the carina in simulated normal airways was longer in the intervention group than in the control group (22.0 [18.0, 29.0] vs 14.0 [10.8, 18.3], P < .0001), while it was shorter for simulated difficult airways (24.0 [16.0, 32.0] s vs 27.0 [21.0, 35.5] s, P = .0425). The survey results indicated that confidence in bronchoscopic intubation increased in both groups, without significant differences in satisfaction, acceptance, or perceived difficulty between the groups. However, the interest ratings were higher in the intervention group than in the control group.

CONCLUSIONS

The 12-hole clock model is a simple and feasible method for improving bronchoscopic skills and promoting interest among trainees.

TRIAL REGISTRATION

NCT05327842 at Clinicaltrials.gov.

The Prevalence of Difficult Airway and Associated Risk Factors in Pediatric Patients: A Cross-sessional Observational Study

BACKGROUND

Difficult airway remains a great challenge in pediatric anesthesia practice. Previously published data show the prevalence of difficult airways in pediatric population varies in a wide range. However, there is a lack of studies in the Asian region.

METHODS

This cross-sectional single-center study was conducted in a tertiary pediatric hospital in China from October 2022 to October 2023. The patients who underwent elective surgery under general anesthesia with tracheal intubation were recruited consecutively. Data on patient characteristics, airway assessment, and airway management information were collected. Multivariable logistic regression analysis was performed to detect the independent variables of difficult airway in pediatric patients.

RESULTS

A total of 18,491 pediatric patients were included in this study. The overall incidence of difficult airways was 0.22%, 39% of whom were unanticipated. Very few previous airway management information was available in the patients presented with a known difficult airway. Patients with younger age, higher American Society of Anesthesiologists (ASA) physical status classification grade, and presented for craniofacial and thoracic surgery were associated with higher incidence of difficult airway. Further multivariable logistic regression analysis revealed that age ≤28 days (OR=50.48), age between 28days and 1 year (OR=6.053), craniofacial surgery (OR=1.81), and thoracic surgery (OR=0.2465) were independent risk factors of increased incidence of difficult airway.

CONCLUSIONS

Our study showed the prevalence of difficult airways in pediatric surgical patients. Patient characteristics, age, and type of surgery were identified as the independent factors associated with increased occurrence of difficult airways. Unanticipated difficult airway was not unusual in our study population, even for the patients with previous surgical history.

Emergency front-of-neck access in pediatric anesthesia: A narrative review

BACKGROUND AND OBJECTIVES

Children undergoing airway management during general anesthesia may experience airway complications resulting in a rare but life-threatening situation known as "Can't Intubate, Can't Oxygenate". This situation requires immediate recognition, advanced airway management, and ultimately emergency front-of-neck access. The absence of standardized procedures, lack of readily available equipment, inadequate knowledge, and training often lead to failed emergency front-of-neck access, resulting in catastrophic outcomes. In this narrative review, we examined the latest evidence on emergency front-of-neck access in children.

METHODS

A comprehensive literature was performed the use of emergency front-of-neck access (eFONA) in infants and children.

RESULTS

Eighty-six papers were deemed relevant by abstract. Finally, eight studies regarding the eFONA technique and simulations in animal models were included. For all articles, their primary and secondary outcomes, their specific animal model, the experimental design, the target participants, and the equipment were reported.

CONCLUSION

Based on the available evidence, we propose a general approach to the eFONA technique and a guide for implementing local protocols and training. Additionally, we introduce the application of innovative tools such as 3D models, ultrasound, and artificial intelligence, which can improve the precision, safety, and training of this rare but critical procedure.

Executive Summary of the 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

The Airway section of the 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) present the Guidelines for the integral management of difficult airway in adult patients. This document provides recommendations based on current scientific evidence, theoretical-educational tools and implementation tools, mainly cognitive aids, applicable to the treatment of the airway in the field of anesthesiology, critical care, emergencies and prehospital medicine. Its principles are focused on the human factors, cognitive processes for decision-making in critical situations and optimization in the progression of the application of strategies to preserve adequate alveolar oxygenation in order to improve safety and quality of care.

Cricothyrotomy - In Unanticipated Difficult Intubation Cases with Respiratory Compromise

Introduction  Cricothyrotomy, percutaneous dilation tracheostomy, and tracheostomy are all cost-effective and safe techniques used in the management of critically ill patients who need an artificial airway other than endotracheal tube ventilation. The present study focused on enlightening on elective and emergency procedures performed on conditions present with difficult airways and also attempts to shed light on the aspects of securing an airway in anticipated and unanticipated difficult intubation. Objective  The objective of the study was to compare the three procedures conducted during difficult airway/failed intubation situations. Methods  The present retrospective observational study was conducted collecting data from patient files obtained at a tertiary healthcare center from 2013 to 2018. The difficult intubation cases were managed by ear, nose, and throat (ENT) surgeons. The study compared three methods: Cricothyrotomy, percutaneous dilation tracheostomy, and tracheostomy based on factors such as procedure duration, complications, and the instruments required for each procedure. Results  The study enrolled 85 patients, 61 males and 24 females, aged between 30 and 70 years old. To perform cricothyrotomy, only a simple blade was required. Cricothyrotomy had the shortest operating time (4.1±3.1 minutes) and the shortest time of full oxygen saturation (3 min). Percutaneous tracheostomy had the least amount of bleeding (1%). Cricothyrotomy significantly showed the least intraoperative bleeding than percutaneous dilation, tracheostomy, and tracheostomy ( p  = 0.001). Conclusion  Cricothyrotomy is preferable as it takes less time to perform, causes less bleeding, and takes the least time for full oxygen saturation than tracheostomy and percutaneous dilatational tracheostomy in "can't intubate, can't oxygenate" patients.

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.

Comparison of UESCOPE VL 400, I-View, Non-Channeled Airtraq Videolaryngoscopes and Macintosh Laryngoscope for Tracheal Intubation in Simulated Out-of-Hospital Conditions: A Randomized Crossover Manikin Study

The aim of the study was to test the hypothesis that the results obtained with three different types of video laryngoscopes (UESCOPE VL-400, I-View, Non-Channeled Aitraq) with and without an endotracheal stylet should be better than the results obtained with a Macintosh laryngoscope in a simulated out-of-hospital scenario by a person without clinical experience. Primary outcome measures were the time taken to successfully achieve tracheal intubation (TI). Secondary outcomes included the grade of glottic view (Cormack and Lehane grades 1-4), the incidence of successful TI, the number of audible dental clicks indicating potential dental damage, the level of effort required to perform TI, and the operator's comfort during the procedure. The time required to achieve tracheal intubation successfully was significantly longer with the Macintosh laryngoscope and Airtraq than with the other video laryngoscopes. The use of the stylet significantly reduced the time required for tracheal intubation with the Macintosh laryngoscope (21.8 sec. vs. 24.0 sec., p = 0.026), UESCOPE VL 400 (18.1 sec. vs. 23.4 sec., p = 0.013), and Airtraq (22.7 sec. vs. 34.5 sec., p < 0.001). There were no significant differences in intubation time when using the I-View with or without stylets. No differences were observed in the Cormack-Lehane grading. The success rate of intubation was 100% for the Macintosh and I-View laryngoscopes used with or without stylets and for the UESCOPE VL 400 and Airtraq laryngoscopes used with stylets. Without stylets, the success rate of intubation was 96.6% for the UESCOPE VL 400 and 86.6% for the Airtraq. There were no significant differences in the risk of dental damage between the Macintosh, UESCOPE VL 400, I-View, and Airtraq laryngoscopes, regardless of the use of stylets (without and with stylets). The use of stylets significantly reduced dental damage only for the Airtraq laryngoscope: 8 (26.6%) vs. 2 (6.6%). Statistically significant differences in perceived exertion were observed between the mentioned laryngoscopes, both with and without stylets. However, there were no differences in the comfort of use between the laryngoscopes, regardless of the use of stylets (without and with stylets. The use of stylets led to better comfort in the case of the Macintosh (2.5 vs. 3, p = 0.043) and UESCOPE VL 400 (2 vs. 3, p = 0.008) laryngoscopes. In our study, the I-View and UESCOPE VL-400 video laryngoscopes provided better intubation results than the Macintosh laryngoscope in terms of time needed to intubate, glottis visibility, and reduction in dental damage. The use of the stylet did not significantly improve the intubation results compared to the results obtained in direct laryngoscopy. Due to the small study group and the manikin model, additional studies should be performed on a larger study group.

Current Status of Difficult Airway Information Dissemination at a Tertiary Pediatric Hospital

OBJECTIVE

Difficult airway is one of the most common potential risk factors for increased fatality in craniofacial/plastic surgery patients. To date, there is no well-established and all-around difficult airway notification system in China, which has recently been recommended by existing guidelines to improve the care of patients with known difficult airways. This study aimed to investigate the current status of critical information communication concerning difficult airway management in our institute.

METHODS

Vital information required to establish a difficult airway registry and notification system was collected through a literature review and expert suggestions. After approval by the Research Ethics Board, 3 online questionnaires were developed and sent to surgeons, anesthesiologists, and proxies of the patients. Knowledge of difficult airways, the willingness to be involved in the difficult airway notification system, and the way to disseminate the information were investigated in the 3 groups. The specific information that was disseminated, required, and available was investigated in the anesthesiologist group.

RESULTS

Compared with the surgeons and anesthesiologists, significantly fewer patients knew the definition of a difficult airway and thought it was a potential risk factor. There were no significant differences in the willingness to be informed of the difficulty encountered during airway management. Significant differences were detected in the willingness and way to disseminate the airway information when the participants communicated with different groups. Significantly more patients would disseminate the information to the surgeon and significantly more surgeons would disseminate the information to the patient and the other surgeon. Significantly more anesthesiologists would disseminate the information to the patient and the other anesthesiologists. A significant difference was observed between what was expected and what was available for the anesthesiologist to retrieve the airway information of a patient with known airway difficulty. Significantly more anesthesiologists would notify only the patient of the diagnosis of a difficult airway both oral and written, whereas significantly more anesthesiologists would notify the other anesthesiologist of the specific difficulties in oral only. Most participants agreed to be involved in the difficult airway notification system despite the significantly lower percentage in the patient group (89%).

CONCLUSIONS

Difficult airway information dissemination is, at the time of this writing, ineffective, which leads to a large gap between the expectation and practice of the anesthesiologist when caring for a patient with a difficult airway. Thus, a difficult airway registry and notification system should be developed, that has a solid foundation in all the participants.

Risk identification and prediction of complaints and misconduct against health practitioners: a scoping review

Identifying the risk and predicting complaints and misconduct against health practitioners are essential for healthcare regulators to implement early interventions and develop long-term prevention strategies to improve professional practice and enhance patient safety. This scoping review aims to map out existing literature on the risk identification and prediction of complaints and misconduct against health practitioners. This scoping review followed Arksey and O'Malley's five-stage methodological framework. A comprehensive literature search was conducted on MEDLINE, EMBASE, and CINAHL databases and finished on the same day (6 September 2021). Articles meeting the eligibility criteria were charted and descriptively analysed through a narrative analysis method. The initial search generated 5473 articles. After the identification, screening, and inclusion process, 81 eligible studies were included for data charting. Three key themes were reported: methods used for identifying risk factors and predictors of the complaints and misconduct, synthesis of identified risk factors and predictors in eligible studies, and predictive tools developed for complaints and misconduct against health practitioners. The findings reveal that risk identification and prediction of complaints and misconduct are complex issues influenced by multiple factors, exhibiting non-linear patterns and being context specific. Further efforts are needed to understand the characteristics and interactions of risk factors, develop systematic risk prediction tools, and facilitate the application in the regulatory environment.

Management of the Difficult Airway: An Appraisal of Clinical Practice Guidelines

OBJECTIVE

Management of the difficult airway can be a challenging process, which necessitates actionable recommendations from well-established guidelines. Herein, clinical practice guideline (CPG) quality is evaluated using the Appraisal of Guidelines for Research and Evaluation (AGREE II) instrument.

STUDY DESIGN

A systematic literature search was performed using Scopus, EMBASE, and MEDLINE via PubMed.

SETTING

Literature database.

METHODS

Data were abstracted from relevant guidelines and appraised by 4 expert reviewers in the 6 domains of quality defined by AGREE II. Intraclass correlation coefficients (ICC) were calculated across domains to quantify interrater reliability.

RESULTS

Twelve guidelines met the inclusion criteria. With a mean quality score of 83.1%, the highest quality guideline was authored by the American Society of Anesthesiologists (ASA). Low-quality content was observed in CPGs authored by the Japanese Society of Anesthesiologists (JSA) and the Chinese Collaboration Group for Emergency Airway Management (CCGEAM). Overall, deficits were most pronounced in domains describing the involvement of stakeholders, developmental rigor, and editorial independence. These findings were consistent among the panel of independent reviewers, with high ICC inter-rater reliability scores of 58.0% to 70.0% for the referenced domains.

CONCLUSION

By providing a comprehensive appraisal of guidelines, this report may serve as a reference for clinicians seeking to understand and improve upon the developmental quality of difficult airway management resources. According to AGREE II criteria for the quality of the guideline creation process, the 2022 ASA guideline outperforms its predecessors.

Scope of artificial intelligence in airway management

The evolution of artificial intelligence (AI) systems in the field of anaesthesiology owes to notable advancements in data processing, databases, algorithmic programs, and computation power. Over the past decades, its accelerated progression has enhanced safety in anaesthesia by improving the efficiency of equipment, perioperative risk assessments, monitoring, and drug administration systems. AI in the field of anaesthesia aims to improve patient safety, optimise resources, and improve the quality of anaesthesia management in all phases of perioperative care. The use of AI is likely to impact difficult airway management and patient safety considerably. AI has been explored to predict difficult intubation to outperform conventional airway examinations by integrating subjective factors, such as facial appearance, speech features, habitus, and other poorly known features. This narrative review delves into the status of AI in airway management, the most recent developments in this field, and its future clinical applications.

Medical Malpractice Claims Related to Performance of Transesophageal Echocardiography by Anesthesiologists

More than 300,000 adults have cardiac surgery in the United States annually, and most undergo intraoperative transesophageal echocardiography (TEE). This patient population is often older with multiple comorbidities, increasing their risk for complications for even routine procedures. Major morbidity or mortality caused by TEE is rare, and it is unknown how often such complications lead to malpractice lawsuits. The authors identified 13 cases out of 2,564 in a closed claims database that involved TEE and reviewed their etiology. Esophageal injury accounted for most of the suits, and only 2 were related to diagnosis. Most expert reviews deemed the care provided by the anesthesiologist to be appropriate.

From Brobdingnag to Lilliput: Gulliver's travels in airway management guidelines

Neonatal airway management comes with exclusive anatomical, physiological, and environmental complexities, and probably higher incidences of accidents and complications. No dedicated airway management guidelines were available until the recently published first joint guideline released by a task force supported by the European Society of Anaesthesiology and Intensive Care and the British Journal of Anaesthesia and focused on airway management in children under 1 yr of age. The guideline offers a series of recommendations based on meticulous methodology including multiple Delphi rounds to complement the sparse and scarce available evidence. Getting back from Brobdingnag, the land of giants with many guidelines available, this guideline represents a foundational cornerstone in the land of Lilliput.

Prevalence and risk factors of difficult mask ventilation: A systematic review and meta-analysis

STUDY OBJECTIVE

This meta-analysis aimed at identifying the risk factors for and their strengths in predicting difficult mask ventilation (MV) through a systematic approach.

DESIGN

Meta-analysis of observational studies.

SETTING

Operating room.

INTERVENTION

Airway- or patient-related risk factors for difficult MV reported in over 20% of eligible studies identified through literature review.

PATIENTS

Adults receiving anesthetic induction with requirement of MV.

MEASUREMENTS

Databases including EMBASE, MEDLINE, Google Scholar, and Cochrane Library were searched from inception to July 2022. The primary outcomes were the identification of commonly reported risk factors for MV and a comparison of their strengths in difficult MV prediction, while the secondary outcomes were the prevalence of difficult MV in the general population and those with obesity.

MAIN RESULTS

Meta-analysis of 20 observational studies involving 335,846 patients identified 13 risk factors with predictive strengths (all p < 0.05): neck radiation (OR = 5.0, five studies, n = 277,843), increased neck circumference (OR = 4.04, 11 studies, n = 247,871), obstructive sleep apnea (OSA) (OR = 3.61, 12 studies, n = 331,255), presence of beard (OR = 3.35, 12 studies, n = 295,443), snoring (OR = 3.06, 14 studies, n = 296,105), obesity (OR = 2.99, 11 studies, n = 278,297), male gender (OR = 2.76, 16 studies, n = 320,512), Mallampati score III-IV (OR = 2.36, 17 studies, n = 335,016), limited mouth opening (OR = 2.18, six studies, n = 291,795), edentulous (OR = 2.12, 11 studies, n = 249,821), short thyroid-mental distance (OR = 2.12, six studies, n = 328,311), old age (OR = 2, 11 studies, n = 278,750), and limited neck movement (OR = 1.98, nine studies, n = 155,101). The prevalence of difficult MV was 6.1% (16 studies, n = 334,694) and 14.4% (four studies, n = 1152) in the general population and those with obesity, respectively.

CONCLUSIONS

Our results demonstrated the strengths of 13 most common risk factors for predicting difficult MV, which may serve as an evidence-based reference for clinicians to incorporate into their daily practice.

Child and Adolescent Bariatric Surgery in an Urban Tertiary Center: Special Anesthetic Considerations for Obesity

Children and adolescents with obesity who present for weight loss surgery are a unique subset of patients. A thorough understanding of the perioperative needs of these individuals is essential to avoid deleterious complications. This review illustrates the necessity for specialized care, including the continued need of specified drug dosing and a systematic approach in the management of the pediatric bariatric patient.

Incidence, causes, and management of failed awake fibreoptic intubation-A retrospective study of 833 procedures

Awake fibreoptic intubation has been considered a gold standard in the management of the difficult airway. However, failure may cause critical situations. The aim of this study was to investigate the incidence and causes of failed awake fibreoptic intubation at a tertiary care hospital. The study was conducted at St. Olav University Hospital in Trondheim, Norway. Problems occurring during anaesthesia are routinely recorded in the electronic anaesthesia information system (Picis Clinical Solutions Inc.), including difficult intubations. We applied text search on all anaesthesia records between 2011 and 2021 and identified 833 awake fibreoptic intubations. The anaesthesia records were examined to identify failed awake fibreoptic intubations, the cause of failure and how the airway ultimately was secured. Among 233,938 patients who received anaesthesia, 90,397 received tracheal intubation and 833 received awake fibreoptic intubation. Twenty-nine of the procedures failed. In nine patients the failure caused loss of airway control with desaturation and hypoventilation. The major causes of failure were dislodged tube after induction of general anaesthesia (n = 8), patient distress (n = 5), tube not able to pass (n = 5), and airway bleeding (n = 3). The situations were primarily solved using direct laryngoscopy, with or without bougie, or with video laryngoscopy. Tracheostomy was performed in four patients. Awake fibreoptic intubation failed in 3.5% of patients, most often due to dislocation, problems passing the tracheal tube, or patient discomfort. The failure rate was higher than in previous studies.

The Impact of Implementing the Vortex Approach on Airway Management Performance in Stressed Medical Students: A Randomized Controlled Simulation Study

BACKGROUND The ability to manage airways in emergencies is paramount, especially for less experienced medical students. Although the Vortex Approach, a useful scheme to support decision-making during airway management, promises structured guidance, there's limited research on its benefits among students. Our study aimed to evaluate student proficiency in a simulated difficult airway scenario and assess the advantages of the Vortex Approach. MATERIAL AND METHODS Medical students initially practiced on low-fidelity mannequins. Subsequently, they were divided into Vortex (n=48) and control groups (n=48). The Vortex group received specialized training. Both groups encountered a simulated scenario focusing on proper ventilation and supraglottic device insertion when traditional intubation failed. Performance was assessed using the airway management outcome score (AMOS). RESULTS The Vortex-trained group demonstrated superior capabilities. Fewer participants exceeded 3 lifeline interventions (4.2% vs 16.7%, P=0.046). The Vortex group consistently optimized subsequent attempts (31.3% vs 10.4%, P=0.01) and reduced prolonged apnea episodes (47.9% vs 81.3%, P=0.0009). Their AMOS scores were notably higher (56.3% vs 27.1%, AMOS=2, P=0.002), reflecting better patient outcomes (41.7% vs 10.4%, P=0.0005). CONCLUSIONS There is a marked need to enhance airway management skills among senior medical students. The Vortex Approach, even after brief exposure, yields significant skill improvements, underscoring its potential as a pivotal component in medical training. Integrating it into the curriculum could bridge the evident skill gap, optimizing future patient care.

Development and validation of a regression model with nomogram for difficult video laryngoscopy in Chinese population: a prospective, single-center, and nested case-control study

Background

Airway management failure is associated with increased perioperative morbidity and mortality. Airway-related complications can be significantly reduced if difficult laryngoscopy is predicted with high accuracy. Currently, there are no large-sample studies on difficult airway assessments in Chinese populations. An airway assessment model based on the Chinese population is urgently needed to guide airway rescue strategy.

Methods

This prospective nested case-control study took place in a tertiary hospital in Shanghai, China. Information on 10,549 patients was collected, and 8,375 patients were enrolled, including 7,676 patients who underwent successful laryngoscopy and 699 patients who underwent difficult laryngoscopy. The baseline characteristics, medical history, and bedside examinations were included as predictor variables. Laryngoscopy was defined as 'successful laryngoscopy' based on a Cormack-Lehane Grades of 1-2 and as 'difficult laryngoscopy' based on a Cormack-Lehane Grades of 3-4. A model was developed by incorporating risk factors and was presented in the form of a nomogram by univariate logistic regression, least absolute shrinkage and selection operator, and stepwise logistic regression. The main outcome measures were area under the curve (AUC), sensitivity, and specificity of the predictive model.

Result

The AUC value of the prediction model was 0.807 (95% confidence interval [CI]: 0.787-0.828), with a sensitivity of 0.730 (95% CI, 0.690-0.769) and a specificity of 0.730 (95% CI, 0.718-0.742) in the training set. The AUC value of the prediction model was 0.829 (95% CI, 0.800-0.857), with a sensitivity of 0.784 (95% CI, 0.73-0.838) and a specificity of 0.722 (95% CI, 0.704-0.740) in the validation set.

Conclusion

Our model had accurate predictive performance, good clinical utility, and good robustness for difficult laryngoscopy in the Chinese population.

The impact of introducing a videolaryngoscope in the initial training of laryngoscopy for undergraduate medical students: a simulation randomized trial

INTRODUCTION

Adequate and continuous airway management by health professionals is fundamental to ensure patient safety and protection. Among several techniques, laryngoscopy for orotracheal intubation is considered a basic skill, so it is taught and learned in medical school and used during the future years of professional practice. However, in some clinical scenarios, physical and anatomical characteristics can make laryngoscopy exceedingly difficult. In the last decade, some new devices have emerged to apply indirect or video-assisted imaging systems, so-called videolaryngoscopes. They have shown great efficiency in difficult intubation cases and have improved teaching and training. Our study introduced a videolaryngoscope, the McGrath... MAC, in the regular laryngoscopy training rotation for 3rd-year undergraduate medical students and evaluated whether there was any associated optimization of the students...

PERFORMANCE

METHOD

Students from two different classes and years (2017 and 2018) were randomly divided into two groups and received theoretical and practical training in the techniques of Direct Laryngoscopy (DL) and Videolaryngoscopy (VL). The students in each group applied the manoeuvres and simulated three tracheal intubation attempts on mannequins. They were evaluated for their success rate on the first attempt, the time required to finalize the intubation, and the visualization of the glottic structures according to the classification of Cormack-Lehane (C&L).

RESULTS

Two hundred and four students with an average age of 21.ß...ß2 years participated in the study; the groups were similar. There was a significant difference between the VL and DL groups in the 1st attempt success rate (97% and 89.4%, respectively, p.ß=.ß0.0497 ... 95% CI), but such a difference was not seen for the other attempts or regarding the number of oesophageal intubations (3% and 7.7%). The students in the VL group were faster than those in the DL group in all intubation attempts; in parallel, the vast majority of the VL group reported excellent visualization conditions, with 75% of the attempts classified as Cormack-Lehane grade 1.

CONCLUSION

The introduction of a videolaryngoscope in medical students... training improved the visualization of anatomical structures and allowed tracheal intubation maneuvers to be performed faster and with a higher success rate on the first attempt. Thus, under the conditions of this prospective study, the videolaryngoscope had a positive impact on training and proved to be a promising tool for teaching laryngoscopy.

Preoperative airway ultrasound assessment in the sniffing position: a prospective observational study

BACKGROUND

Clinical airway screening tests intend to predict difficult airways, but none have a high predictive value. Recent systematic reviews correlate ultrasound with difficult laryngoscopy. This study aimed primarily to correlate ultrasound measurements of anatomical upper airway structures in the sniffing position with difficult direct laryngoscopy. The secondary aim was to observe gender-based differences.

METHODS

This prospective, cross-sectional, single-center observational study included 209 patients requiring general anesthesia for elective surgery. Preoperatively, we performed six clinical airway assessments and three ultrasound measurements, which were the Distance from Skin to the Hyoid Bone (DSHB), to the Epiglottis (DSE), and to the anterior commissure of the vocal cords (DSAC) in a sniffing position. Benumof's criteria for the "best view at the first attempt" for direct laryngoscopy assessed the difficulty of laryngoscopy.

RESULTS

The distance from skin to the epiglottis was the best predictor of direct difficult laryngoscopy (defined as Cormack-Lehane grade ≥ 2b) with a minimum thickness cut-off at 2.70 ± 0.19 cm (sensitivity 91.3%; specificity 96.9%). The skin to the hyoid bone distance cut-off was 1.41 ± 0.30 cm with moderate correlation (sensitivity 80.4%; specificity 60.1%). No correlation was found for the distance to the anterior commissure of the vocal cords. In women compared to men, the skin to the epiglottis distance was more sensitive (92.3% vs. 90.9%) and specific (98.8% vs. 95.2%).

CONCLUSIONS

DSE in the sniffing position is the most reliable parameter for preoperative airway ultrasound assessment in the Caucasian population, with higher sensitivity and specificity in women, and might be considered as an independent predictor for direct difficult laryngoscopy.

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.

Nasendoscopy to Predict Difficult Videolaryngoscopy: A Multivariable Model Development Study

BACKGROUND

Transnasal videoendoscopy (TVE) is the standard of care when staging pharyngolaryngeal lesions. This prospective study determined if preoperative TVE improves the prediction of difficult videolaryngoscopic intubation in adults with expected difficult airway management in addition to the Simplified Airway Risk Index (SARI).

METHODS

374 anesthetics were included (252 with preoperative TVE). The primary outcome was a difficult airway alert issued by the anesthetist after Macintosh videolaryngoscopy. SARI, clinical factors (dysphagia, dysphonia, cough, stridor, sex, age and height) and TVE findings were used to fit three multivariable mixed logistic regression models; least absolute shrinkage and selection operator (LASSO) regression was used to select co-variables.

RESULTS

SARI predicted the primary outcome (odds ratio [OR] 1.33; 95% confidence interval [CI] 1.13-1.58). The Akaike information criterion for SARI (327.1) improved when TVE parameters were added (311.0). The Likelihood ratio test for SARI plus TVE parameters was better than for SARI plus clinical factors (p < 0.001). Vestibular fold lesions (OR 1.82; 95% CI 0.40-8.29), epiglottic lesions (OR 3.37; 0.73-15.54), pharyngeal secretion retention (OR 3.01; 1.05-8.63), restricted view on rima glottidis <50% (OR 2.13; 0.51-8.89) and ≥50% (OR 2.52; 0.44-14.56) were concerning.

CONCLUSION

TVE improved prediction of difficult videolaryngoscopy in addition to traditional bedside airway examinations.

Implementing an Interprofessional Difficult Airway Response Team to Identify and Manage High-Risk Airways

OBJECTIVE

To describe a multidisciplinary approach to and results from the creation of a difficult airway response team (DART) to address the management of inpatient loss of airway events.

METHODS

Description of an interprofessional process to establish and sustain a DART program at a tertiary care hospital. An Institutional Review Board-approved retrospective review of the quantitative results was conducted from November 2019 through March 2021.

RESULTS

After establishing the existing processes for difficult airway management, a focus on "work as imagined" identified 4 pillars to address the goal for the project of bringing the right providers with the right equipment to the right patients at the right time through DART equipment carts, an expanded DART code team, a screening tool to identify patients with at-risk airways and unique messaging for DART code alerts. "Work as done" was assessed through simulations. Educational efforts included further simulations and group teaching. Sustainability was achieved through ongoing e-learning and bidirectional feedback. During the period of study, there were 40,752 patients admitted and 28,013 (69%) screens completed. At-risk airways were identified in 4282 admissions (11%), most commonly due to a history of a difficult airway (19%) and elevated body mass index (16%). The DART responded to 126 codes. There were no airway-related deaths or serious adverse events.

DISCUSSION

A successful DART program was created, optimized, and sustained using components of interprofessional meetings, simulation, bidirectional feedback, and quantitative analysis.

IMPLICATIONS FOR PRACTICE

The techniques described can serve to guide groups who identify a quality improvement project that involves interactions between multiple stakeholders.

Nasopharyngeal Ventilation Compared to Facemask Ventilation: A Prospective, Randomized, Crossover Trial in Two Different Elective Cohorts

BACKGROUND

Facemask ventilation is routinely used to preoxygenate patients before endotracheal intubation during anesthesia induction or to secure ventilation in patients with respiratory insufficiency. Occasionally, facemask ventilation cannot be performed adequately. The placement of a regular endotracheal tube through the nose into the hypopharynx may be a valid alternative to improve ventilation and oxygenation before endotracheal intubation (nasopharyngeal ventilation). We tested the hypothesis that nasopharyngeal ventilation is superior in its efficacy compared to traditional facemask ventilation.

METHODS

In this prospective, randomized, crossover trial, we enrolled surgical patients requiring either nasal intubation (cohort #1, n = 20) or patients who met "difficult to mask ventilate" criteria (cohort #2, n = 20). Patients in each cohort were randomly assigned to receive pressure-controlled facemask ventilation followed by nasopharyngeal ventilation or vice versa. The ventilation settings were kept constant. The primary outcome was tidal volume. The secondary outcome was the difficulty of ventilation, measured using the Warters grading scale.

RESULTS

Tidal volume was significantly increased by nasopharyngeal ventilation in cohort #1 (597 ± 156 ml vs.462 ± 220 ml, p = 0.019) and cohort #2 (525 ± 157 ml vs.259 ± 151 ml, p < 0.01). Warters grading scale for mask ventilation was 0.6 ± 1.4 in cohort #1, and 2.6 ± 1.5 in cohort #2.

CONCLUSION

Patients at risk for difficult facemask ventilation may benefit from nasopharyngeal ventilation to maintain adequate ventilation and oxygenation before endotracheal intubation. This ventilation mode may offer another option for ventilation at induction of anesthesia and during the management of respiratory insufficiency, especially in the setting of "unexpected" ventilation difficulty.

Preoxygenation with standard facemask combining apnoeic oxygenation using high flow nasal cannula versuss standard facemask alone in patients with and without obesity: the OPTIMASK international study

BACKGROUND

Combining oxygen facemask with apnoeic oxygenation using high-flow-nasal-oxygen (HFNO) for preoxygenation in the operating room has not been studied against standard oxygen facemask alone. We hypothesized that facemask-alone would be associated with lower levels of lowest end-tidal oxygen (EtO2) within 2 min after intubation in comparison with facemask combined with HFNO.

METHODS

In an international prospective before-after multicentre study, we included adult patients intubated in the operating room from September 2022 to December 2022. In the before period, preoxygenation was performed with facemask-alone, which was removed during laryngoscopy. In the after period, facemask combined with HFNO was used for preoxygenation and HFNO for apnoeic oxygenation during laryngoscopy. HFNO was maintained throughout intubation. The primary outcome was the lowest EtO2 within 2 min after intubation. The secondary outcome was SpO2 ≤ 95% within 2 min after intubation. Subgroup analyses were performed in patients without and with obesity. This study was registered 10 August 2022 with ClinicalTrials.gov, number NCT05495841.

RESULTS

A total of 450 intubations were evaluated, 233 with facemask-alone and 217 with facemask combined with HFNO. In all patients, the lowest EtO2 within 2 min after intubation was significantly lower with facemask-alone than with facemask combined with HFNO, 89 (85-92)% vs 91 (88-93)%, respectively (mean difference - 2.20(- 3.21 to - 1.18), p < 0.001). In patients with obesity, similar results were found [87(82-91)% vs 90(88-92)%, p = 0.004]; as in patients without obesity [90(86-92)% vs 91(89-93)%, p = 0.001)]. SpO2 ≤ 95% was more frequent with facemask-alone (14/232, 6%) than with facemask combined with HFNO (2/215, 1%, p = 0.004). No severe adverse events were recorded.

CONCLUSIONS

Combining facemask with HFNO for preoxygenation and apnoeic oxygenation was associated with increased levels of lowest EtO2 within 2 min after intubation and less desaturation.

AIRWAY MANAGEMENT GUIDELINES IN OBSTETRICS

Anatomic and physiologic changes during pregnancy make it more difficult to establish a safe airway in pregnant women in case of the need for surgery under general anesthesia than in the non-obstetric population. The inability to ventilate and oxygenate is one of the most common causes of morbidity and mortality associated with general anesthesia for cesarean section. The aim of this paper is to present and analyze modern guidelines and algorithms for the management of difficult airway in obstetrics as an important segment of anesthesiology practice. Modern difficult airway management guidelines for pregnant women describe the procedure of difficult facemask ventilation, difficult airway management by using supraglottic devices, difficult endotracheal intubation, and emergency cricothyrotomy or tracheotomy in a situation where oxygenation and ventilation are impossible. Algorithms describe the procedures and equipment for each variant of difficult airway and decision-making strategies in situations when neither airway nor adequate oxygenation can be provided. Croatian anesthesiologists in most obstetric departments have appropriate equipment, as well as necessary experience in difficult airway management for pregnant women, and modern algorithms from the most developed countries can be adopted and accommodated to our daily practice, as well as incorporated into the training curricula of residents.

Incidence and diagnostic validity of difficult airway in emergency departments in China: a cross-sectional survey

Background

The difficult airway is a topic of concern for any physician performing intubation. Severe adverse events which can happen because of an unexpected difficult airway emphasize the importance of prediction. This study aimed to investigate the incidence of difficult airways in emergency departments in mainland China and ascertain the predictive value of common assessment formulas.

Methods

This study was a multicentral, cross-sectional investigation of patients intubated in emergency departments in mainland China between March 1-30, 2021. Frequencies and percentages were calculated for patient characteristics. Diagnostic values were analyzed by sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, the area under the curve, and corresponding P values.

Results

Nine hundred and eighty-five patients in 41 hospitals were enrolled in the study. Elderly male patients occupied most of the intubated patients. The difficult face mask ventilation rate (8.2%) was higher, but the difficult glottic exposure (6.8%) and intubation (2.1%) rates were low, while there was widespread use of enhanced visualization equipment (80.6%). Four combined emergency applicable evaluation methods showed a certain predictive value for the difficult airway with a sensitivity [0.71; 95% confidence interval (CI): 0.47-0.89], specificity (0.79; 95% CI: 0.76-0.81), and the area under the curve (0.75; 95% CI: 0.64-0.87, P<0.01).

Conclusions

Despite an insufficient predictive ability for current difficult airway evaluation methods, there were relatively low rates of difficult airways during ED intubations in mainland China. Continuing focus on the difficult airway problems and optimizing airway assessment are required.

Emergency treatment of airway obstruction caused by a laryngeal neuroendocrine tumor: A case report

RATIONALE

Laryngeal obstruction is a life-threatening adverse event that requires urgent and appropriate management, particularly in patients with coexisting cardiopulmonary and brain comorbidities. However, laryngeal obstruction caused by laryngeal neuroendocrine tumors has rarely been reported.

PATIENT CONCERNS

Neuroendocrine tumors can cause pathological changes in the neuro-humoral system, and asphyxia caused by airway obstruction has a more adverse effect on patients with neuroendocrine tumors.

DIAGNOSES

We report the case of a 64-year-old man with clinical manifestations of dyspnea. Preoperative and intraoperative pathological examination indicated that the patient was diagnosed with life-threatening airway obstruction caused by a laryngeal neuroendocrine tumor, pneumonia, and scoliosis.

INTERVENTIONS

The patient underwent laryngeal tumor resection under general anesthesia. He was recovered well and was generally good without the necessity of undergoing radiotherapy and chemotherapy at the 6-months follow-up.

OUTCOMES

This case report has provided an emergency treatment strategy associated with awake intubation. We concluded that flexible establishment of an artificial airway, skilled anesthesia and surgical manipulation, and necessary postoperative intensive care are extremely important for improving the prognosis of patients with severely difficult airway. It is noteworthy that the timely adjust for endotracheal intubation strategy according to the patient's response is needed. It is important for the long-term prognosis of patients to avoid the establishment of a traumatic artificial airway and the occurrence of adverse complications.

LESSONS

1. Introduction; 2. Case presentation; 3. Discussion; 4. Conclusion.

[Difficult Airway Management (DAM) Algorithms - A narrative synopsis and site assessment]

Centuries ago an "algorithm" was originally inaugurated to depicture a pathway to solve mathematical problems using a decision tree. Nowadays this tool is also well established in clinical medicine. Ever since management errors in difficult airway handling and subsequent litigations remain high referring to ASA closed claims database. However, even since 2010, the ESA postulates every institution dealing with airway management should have a DAM algorithm (ESA Declaration of Helsinki on Patient Safety in Anaesthesiology). In 2018 a systematic review of 38 international DAM algorithms was published; most of them show a four-step flow chart: failed tracheal intubation, insufficient bag-mask ventilation and supraglottic airway, leads to establish an emergency sugical airway. In conclusion authors state that a universal, globally valid, DAM algorithm is lacking. German language guideline development is governed by the AWMF, which labels guidelines with the highest evidence levels and methodological strength "S3". The ASA published a revised DAM practice guideline in 2022, which was developed by 13 international members and was endorsed by international anesthesiological societies. - Though it is based on a systematic literature search and evaluation, final recommendations (without grading) were generated by a survey among experts in the field: Pre-procedural evaluation of the airway is essential; meanwhile more data are available especially regarding ultrasound examination of the upper airway and in 2022 a promising nomogram was developed for the prediction of difficult laryngoscopy. Pre-procedural planning of expected DAM: it should be decided beforehand, if awake intubation is feasible for the patient. Preoxygenation of every elective patient (3 mins with PEEP 5 cmH₂O, aim: 95% pulse oxymetry) and continuous nasal high-flow oxygen delivery during airway management. In case of unexpectedly difficult/emergency airway, ASA recommends: call for help, use cognitive aid (algorithm), consider restoration of spontaneous breathing, adjust bag-mask ventilation, monitor time passing; if "cannot intubate, cannot oxygenate" situation occurs (etCO₂ < 10 mmHg, < 80% pulse oxymetry) establish surgical airway; if failed consider ECMO therapy, if feasible and available. ASA restricts intubation attempts to 3+ based on experience and decision of the clinician, however evidence shows, that attempts should not exceed 2 attempts to avoid serious complications, e.g. hyoxemia and even cardiopulmonary resuscitation (CPR). Additionally, we recommend a cockpit strategy for airway management using crisis resource elements as used in aviation (situation awareness, sterile communication, read-back/hear-back and canned decisions) and a supervisor/team leader as already established in CPR. Last, but not least, continuous airway management training increases algorithm adherence.

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.

The Use of McGrath MAC Video Laryngoscope Versus McCoy Laryngoscope in Adults with Anticipated Difficult Airway Undergoing Elective Surgery

Background

Difficult airway management remains one of the most challenging clinical situations encountered by anaesthetists.

Aim

The study compared the effectiveness of the McGrath MAC video laryngoscope to the McCoy® laryngoscope in patients with difficult airway.

Materials and Methods

Following the institution's ethical approval, the randomised controlled trial was conducted involving 74 adults with American Society of anaesthesiologists' physical status (ASA) grading of I-III scheduled for elective surgery. The Patients were randomised into either group MVL (McGrath MAC) or group MCC (McCoy) and intubated after preoxygenation with 100% oxygen and administration of IV propofol and suxamethonium. The Intubation Difficulty Score (IDS), success rate of intubation, time to intubation, number of optimising manoeuvres and complications was assessed. Statistical analysis was performed using the statistical Package for Social Sciences (SPSS) version 24.0 computer software (IBM SPSS Statistics, IBM Corp. NY, United States). Numerical and categorical data were compared using the student's t-test and Chi square (χ2) test respectively. A value of P < 0.05 was considered statistically significant.

Results

Lower IDS scores were noted in the McGrath group; 54.1% vs. 5.4% of patients had IDS score of 0 in the McGrath and McCoy groups respectively, (P < 0.001). Overall success rate was higher in the McGrath group (100% vs. 89.1%), P = 0.040.

Conclusion

Lower IDS scores and improved intubation success rate was achieved with the McGrath compared with the McCoy laryngoscope in patients with predicted difficult airway. The McGrath has proved to be useful in managing patients with difficult airway.

Unanticipated Difficult Airway During Elective Surgery: A Case Report and Review of Literature

Difficult airway during anesthesia is responsible for several cases of morbidity and mortality worldwide, especially when it is unanticipated. Patients with either history of or with predictive factors of a difficult airway show better outcomes since all preventative measures will ensure patient safety. Approximately 30% of all deaths attributed to anesthesia are related to unsuccessful intubation. In this article, we discuss a patient who had a tracheostomy following an unanticipated difficult airway with undiagnosed subglottic stenosis and also reviewed the current literature on the difficult airway.

Morphological specificity analysis of an image-based 3D model of airway filling in a difficult airway

Background

The purpose of this study was to analyze position-specific morphological changes of the upper airway and to further assess the impact of these changes in difficult airway during intubation.

Methods

This observational comparative study included two groups (n = 20 patients/group): Group A had normal airway and Group B had difficult airway. Data obtained from two-dimensional magnetic resonance imaging were imported to Mimics V20.0 software for processing. We then reconstructed three-dimensional models of upper airway filling in patients in the supine and maximum extension position based on the imaging data. Those models were projected on coronal, sagittal, and horizontal planes to investigate multiple morphological features. We measured the surface area, radial length, and corner angle of the projected areas.

Results

Group A had larger upper airway filling volumes compared to Group B The volumes for the supine position were 6,323.83 ± 156.06 mm3 for Group A and 5,336.22 ± 316.13 mm3 for Group B (p = 0.003). The volumes the maximum extension position were 9,186.58 ± 512.61 mm3 for Group A and 6,735.46 ± 794.63 mm3 for Group B (p = 0.003). Airway volume increased in the upper airway filling model as the body position varied from the supine to maximum extension position (Group A: volume increase 2,953.75 ± 524.6 mm3, rate of change 31%; Group B: volume increase 1,632.89 ± 662.66 mm3, rate of change 25%; p = 0.052).

Conclusion

The three-dimensional reconstruction model developed in this study was used to digitally quantify morphological features of a difficult airway and could be used as a novel airway management assessment tool.

Design and Implementation of Airway Response Teams to Improve the Practice of Emergency Airway Management

Emergency airway management (EAM) is a commonly performed procedure in the critical care setting. Despite clinical advances that help practitioners identify patients at risk for having a difficult airway, improved airway management tools, and algorithms that guide clinical decision-making, the practice of EAM is associated with significant morbidity and mortality. Evidence suggests that a dedicated airway response team (ART) can help mitigate the risks associated with EAM and provide a framework for airway management in acute settings. We review the risks and challenges related to EAM and describe strategies to improve patient care and outcomes via implementation of an ART.

Videolaryngoscopy as a first-intention technique for tracheal intubation in unselected surgical patients: a before and after observational study

BACKGROUND

Using a Macintosh-style videolaryngoscope as a first-intention device for tracheal intubation of unselected patients in the operating room has not often been studied. We hypothesised that using a Macintosh-style videolaryngoscope as a first-intention device is associated with an increased proportion of easy tracheal intubation.

METHODS

In a quality improvement project for airway management aimed at implementing a Macintosh-style videolaryngoscope as a first-intention device, we included all consecutive tracheal intubations in adults from March, 2017 to September, 2020 in two French teaching hospitals. We divided the cohort into three temporal cohorts: the pre-intervention, implementation, and post-intervention periods. The primary outcome was the proportion of easy airway management. The secondary outcomes were the rescue technique, Cormack-Lehane III or IV view, and operator-reported difficulty of intubation. Data from one hospital compliant with the quality improvement project were compared with data from a non-compliant hospital.

RESULTS

A total of 26 692 tracheal intubations were performed. Among 11 938 intubations included in the compliant hospital, 5487 were included in the pre-intervention, 1845 in the implementation, and 4606 in the post-intervention periods. In comparison to the pre-intervention period, the proportions of easy tracheal intubation increased from 94.3% (5177 of 5487) to 98.7% (4547 of 4606)) in the post-intervention period (+4.4% [95% confidence interval 3.7-5.1%], P<0.001). In comparison to the pre-intervention period, all secondary outcome proportions were significantly lower in the post-intervention period. No significant changes were noted in the non-compliant hospital between the pre- and post-intervention periods.

CONCLUSIONS

Using a Macintosh-style videolaryngoscope as a first-intention device for tracheal intubation in the operating room was associated with a significant increase in the proportion of easy tracheal intubation, compared with use of the standard Macintosh laryngoscope.

Unrecognised oesophageal intubation: time for action

Patients worldwide die every year from unrecognised oesophageal intubation, which is an avoidable complication of airway management usually resulting from human error. Unrecognised oesophageal intubation can occur in any patient of any age whenever intubation occurs regardless of the seniority or experience of the airway practitioner or others involved in the patient's airway management. The tragic fact is that it continues to happen despite improvements in monitoring, airway devices, and medical education. We review these improvements with strategies to eliminate this problem.

A model to predict difficult airway alerts after videolaryngoscopy in adults with anticipated difficult airways - the VIDIAC score

A model to classify the difficulty of videolaryngoscopic tracheal intubation has yet to be established. The videolaryngoscopic intubation and difficult airway classification (VIDIAC) study aimed to develop one based on variables associated with difficult videolaryngoscopic tracheal intubation. We studied 374 videolaryngoscopic tracheal intubations in 320 adults scheduled for ear, nose and throat or oral and maxillofacial surgery, for whom airway management was expected to be difficult. The primary outcome was whether an anaesthetist issued a 'difficult airway alert' after videolaryngoscopy. An alert was issued after 183 (49%) intubations. Random forest and lasso regression analysis selected six intubation-related variables associated with issuing an alert: impaired epiglottic movement; increased lifting force; direct epiglottic lifting; vocal cords clearly visible; vocal cords not visible; and enlarged arytenoids. Internal validation was performed by a 10-fold cross-validation, repeated 20 times. The mean (SD or 95%CI) area under the receiver operating characteristic curve was 0.92 (0.05) for the cross validated coefficient model and 0.92 (0.89-0.95) for a simplified unitary score (VIDIAC score with component values of -1 or 1 only). The calibration belt for the coefficient model was consistent with observed alert probabilities, from 0% to 100%, while the unitary VIDIAC score overestimated probabilities < 20% and underestimated probabilities > 70%. Discrimination of the VIDIAC score for patients more or less likely to be issued an alert was better than discrimination by the Cormack-Lehane classification, with mean (95%CI) areas under the receiver operating characteristic curve of 0.92 (0.89-0.95) vs. 0.75 (0.70-0.80), respectively, p < 0.001. Our model and score can be used to calculate the probabilities of difficult airway alerts after videolaryngoscopy.

Patient Safety During Anesthesia: 100 Years of Progress Documented in Anesthesia & Analgesia

Anesthesiology has evolved to be a leader in addressing patient safety. Our specialty has overcome serious morbidities including explosions, fires, organ toxicity, fatal arrhythmias, and hypoxic brain damage. Anesthesia safety has been significantly improved due to modern drug development, technical advances, and a strong leadership willing to apply human factors and systems' research strategies, but patient safety concerns remain at the forefront as we strive to improve patient care even further. This year marks the centennial year since the publication of the first issue of Anesthesia & Analgesia. Today, the International Anesthesia Research Society (IARS) and Anesthesia & Analgesia continue to advance the boundaries of patient safety by disseminating practice standards, serving as a forum for novel ideas, and supporting research advancements. This review will discuss several topics published in Anesthesia & Analgesia that exemplify steady changes leading to the safe practices that we rely on currently as well as other IARS activities that have advocated and elevated patient safety within the specialty.