Left head rotation (LeHeR), an innovative approach for intubation in patients with missing and loose teeth.

Missing and loose central incisors pose a great difficulty to anaesthesiologists during laryngoscopy and intubation. Left head rotation is a novel technique which facilitates intubation by improving the laryngoscopic view. We report the use of this technique in two patients with missing or loose central incisors to prevent dental trauma.

Endotracheal Intubation via Tracheotomy and Subsequent Thoracotomy in Rats for Non-Survival Applications.

Endotracheal intubation and subsequent ventilation are often basic requirements for translational research in rat models for various interventions that require controlled or high ventilation pressures or access to the thoracic cavity and organs. Conventional endoorotracheal intubation using the anatomically existing route through the mouth is well suited for survival experiments. However, this procedure poses some challenges, including generally higher levels of the required experience and technical skill, more advanced equipment, and greater time effort with relevant intubation failure rates and complications such as tracheal perforation, temporary systemic hypooxygenation, and relevant aerial leakage. This manuscript, therefore, presents a detailed step-by-step protocol for endotracheal intubation through tracheotomy in non-survival rat models when guaranteed intubation success, constant oxygenation levels, high ventilation pressures, or open thoracotomy are required. The protocol emphasizes the importance of meticulous surgical technique to ensure consistent and reliable outcomes, especially for researchers who are inexperienced or lack routine in the technique of endoorotracheal intubation via direct laryngoscopy. This procedure is, therefore, expected to minimize animal suffering and unnecessary animal losses.

Determinants of difficult laryngoscopy based on upper airway indicators: a prospective observational study.

BACKGROUND: The main cause of anesthesia-related deaths is the failure to manage difficult airways. Difficult laryngoscopic exposure is a major cause of unsuccessful management of difficult airways. Inadequate preoperative airway assessment hinders the clinical management of difficult airways cases, emphasizing the critical need for accurate identification of difficult airways. Currently, no definitive and reliable indicators are available to predict a difficult airway. Our study aims to predict laryngoscope exposure risk factors by combining ultrasonically measured upper airway anatomic parameters with physical examination indicators. METHODS: Patients aged 18 to 75 years, classified as American Standards Association (ASA) I-III, and scheduled for elective general anesthesia with endotracheal intubation were included. All patients received the upper airway and ultrasonographic measurements. After anesthesia induction, laryngoscope exposure was analyzed using the Cormack-Lehane grading system, with Grades III and IV as indicative of difficult laryngoscopy. Univariate and multivariate logistic regression analyses were performed to identify reliable indicators for predicting difficult laryngoscopy. Receiver Operating Characteristic (ROC) curve analysis was utilized to assess the predictive performance of each indicator. RESULTS: A total of 1120 patients finished the study, with 710 cases found in Grade I laryngoscopic exposure group, 360 cases in Grade II group, and 50 cases in Grade III group. There was no case observed in Grade IV group, thereby resulting in an incidence of difficult laryngoscopy of 4.46%. Univariate logistic regression analysis revealed that several parameters including age, Body Mass Index (BMI), neck circumference, neck mobility, snoring intensity, as well as ultrasound measurements of the pre-epiglottic space and thyromental distance were identified as significant risk factors for difficult laryngoscopy (P < 0.05). Among these, BMI, and neck circumference exhibited notable predictive value, with Area Under The Curve (AUC) values of 0.746 (95%CI 0.649-0.842) and 0.732 (95%CI 0.638-0.827), respectively. Neck mobility was also identified as an independent risk factor for predicting difficult laryngoscopy (P = 0.009) in multivariate logistic regression analysis, with an AUC of 0.672 (0.562-0.782) in the ROC curve. CONCLUSIONS: Our findings revealed a direct correlation between difficult laryngoscopy and age, BMI, neck circumference, neck mobility, snoring intensity, as well as ultrasound measurements of the pre-epiglottic space and thyromental distance. Furthermore, neck mobility was identified as an independent predictive factor. TRIAL REGISTRATION: The trial was registered prior to patient enrollment at clinicaltrials.gov (register no. ChiCTR2100053826, Date of registration: November 30, 2021).

Classification of laryngeal diseases including laryngeal cancer, benign mucosal disease, and vocal cord paralysis by artificial intelligence using voice analysis.

Voice change is often the first sign of laryngeal cancer, leading to diagnosis through hospital laryngoscopy. Screening for laryngeal cancer solely based on voice could enhance early detection. However, identifying voice indicators specific to laryngeal cancer is challenging, especially when differentiating it from other laryngeal ailments. This study presents an artificial intelligence model designed to distinguish between healthy voices, laryngeal cancer voices, and those of the other laryngeal conditions. We gathered voice samples of individuals with laryngeal cancer, vocal cord paralysis, benign mucosal diseases, and healthy participants. Comprehensive testing was conducted to determine the best mel-frequency cepstral coefficient conversion and machine learning techniques, with results analyzed in-depth. In our tests, laryngeal diseases distinguishing from healthy voices achieved an accuracy of 0.85-0.97. However, when multiclass classification, accuracy ranged from 0.75 to 0.83. These findings highlight the challenges of artificial intelligence-driven voice-based diagnosis due to overlaps with benign conditions but also underscore its potential.

Video Laryngoscopy vs Direct Laryngoscopy for Endotracheal Intubation in the Operating Room: A Cluster Randomized Clinical Trial.

Importance: Endotracheal tubes are typically inserted in the operating room using direct laryngoscopy. Video laryngoscopy has been reported to improve airway visualization; however, whether improved visualization reduces intubation attempts in surgical patients is unclear. Objective: To determine whether the number of intubation attempts per surgical procedure is lower when initial laryngoscopy is performed using video laryngoscopy or direct laryngoscopy. Design, Setting, and Participants: Cluster randomized multiple crossover clinical trial conducted at a single US academic hospital. Patients were adults aged 18 years or older having elective or emergent cardiac, thoracic, or vascular surgical procedures who required single-lumen endotracheal intubation for general anesthesia. Patients were enrolled from March 30, 2021, to December 31, 2022. Data analysis was based on intention to treat. Interventions: Two sets of 11 operating rooms were randomized on a 1-week basis to perform hyperangulated video laryngoscopy or direct laryngoscopy for the initial intubation attempt. Main Outcomes and Measures: The primary outcome was the number of operating room intubation attempts per surgical procedure. Secondary outcomes were intubation failure, defined as the responsible clinician switching to an alternative laryngoscopy device for any reason at any time, or by more than 3 intubation attempts, and a composite of airway and dental injuries. Results: Among 8429 surgical procedures in 7736 patients, the median patient age was 66 (IQR, 56-73) years, 35% (2950) were women, and 85% (7135) had elective surgical procedures. More than 1 intubation attempt was required in 77 of 4413 surgical procedures (1.7%) randomized to receive video laryngoscopy vs 306 of 4016 surgical procedures (7.6%) randomized to receive direct laryngoscopy, with an estimated proportional odds ratio for the number of intubation attempts of 0.20 (95% CI, 0.14-0.28; P < .001). Intubation failure occurred in 12 of 4413 surgical procedures (0.27%) using video laryngoscopy vs 161 of 4016 surgical procedures (4.0%) using direct laryngoscopy (relative risk, 0.06; 95% CI, 0.03-0.14; P < .001) with an unadjusted absolute risk difference of -3.7% (95% CI, -4.4% to -3.2%). Airway and dental injuries did not differ significantly between video laryngoscopy (41 injuries [0.93%]) vs direct laryngoscopy (42 injuries [1.1%]). Conclusion and Relevance: In this study among adults having surgical procedures who required single-lumen endotracheal intubation for general anesthesia, hyperangulated video laryngoscopy decreased the number of attempts needed to achieve endotracheal intubation compared with direct laryngoscopy at a single academic medical center in the US. Results suggest that video laryngoscopy may be a preferable approach for intubating patients undergoing surgical procedures. Trial Registration: ClinicalTrials.gov Identifier: NCT04701762.

Predictive and protective factors for failing first pass intubation in prehospital rapid sequence intubation: an aetiology and risk systematic review with meta-analysis.

BACKGROUND: Prehospital rapid sequence intubation first pass success rates vary between 59% and 98%. Patient morbidity is associated with repeat intubation attempts. Understanding what influences first pass success can guide improvements in practice. We performed an aetiology and risk systematic review to answer the research question 'what factors are associated with success or failure at first attempt laryngoscopy in prehospital rapid sequence intubation?'. METHODS: MEDLINE, EMBASE, CINAHL, and Cochrane Library were searched on March 3, 2023 for studies examining first pass success rates for rapid sequence intubation of prehospital live patients. Screening was performed via Covidence, and data synthesised by meta-analysis. The review was registered with PROSPERO and performed and reported as per Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. RESULTS: Reasonable evidence was discovered for predictive and protective factors for failure of first pass intubation. Predictive factors included age younger than 1 yr, the presence of blood or fluid in the airway, restricted jaw or neck movement, trauma patients, nighttime procedures, chronic or acute distortions of normal face/upper airway anatomy, and equipment issues. Protective factors included an experienced intubator, adequate training, use of certain videolaryngoscopes, elevating the patient on a stretcher in an inclined position, use of a bougie, and laryngeal manoeuvres. CONCLUSIONS: Managing bloody airways, positioning well, using videolaryngoscopes with bougies, and appropriate training should be further explored as opportunities for prehospital services to increase first pass success. Heterogeneity of studies limits stronger conclusions. SYSTEMATIC REVIEW PROTOCOL: PROSPERO (CRD42022353609).

A review of the current status and progress in difficult airway assessment research.

A difficult airway is a situation in which an anesthesiologist with more than 5 years of experience encounters difficulty with intubation or mask ventilation. According to the 2022 American Society of Anesthesiologists Practice Guidelines for the Management of Difficult Airway, difficult airways are subdivided into seven detailed categories. This condition can lead to serious adverse events and therefore must be diagnosed accurately and quickly. In this review, we comprehensively summarize and discuss the different methods used in clinical practice and research to assess difficult airways, including medical history, simple bedside assessment, comprehensive assessment of indicators, preoperative endoscopic airway examination, imaging, computer-assisted airway reconstruction, and 3D-printing techniques. We also discuss in detail the latest trends in difficult airway assessment through mathematical methods and artificial intelligence. With the continuous development of artificial intelligence and other technologies, in the near future, we will be able to predict whether a patient has a difficult airway simply by taking an image of the patient's face through a cell phone program. Artificial intelligence and other technologies will bring great changes to the development of airway assessment, and at the same time raise some new questions that we should think about.

Validity, reliability and reproducibility of the VLS parameters form for the collection of videolaryngostroboscopic basic findings.

OBJECTIVE: The videolaryngostroboscopy parameters form (VLSP form) is a diagnostic tool for the collection of videolaryngostroboscopic basic findings through the evaluation of 12 parameters. The aim of the present study is to preliminarily investigate intra- and inter-rater reliability, validity and responsiveness of the VLSP form. METHODS: A study on a total amount of 160 forms for the evaluation of VLS basic findings was carried out. 80 forms were scored through the VLSP form and 80 with the Voice Vibratory Assessment with Laryngeal Imaging (VALI) form Stroboscopy (S) by four expert phoniatricians, that blindly scored the VLS recordings of 5 subjects without voice disorders and 5 patients with organic voice disorder before and after successful phonosurgery. Intra-rater and inter-rater analysis have been performed for both forms. The scores obtained through VLSP form and VALI form S have been compared to analyse concurrent validity, while VLSP scores before and after phonosurgery have been compared to analyse responsiveness. Finally, each rater annotated the "difficulty" in rating every parameter and its "importance" for the diagnosis. RESULTS: The VLSP form showed good inter- and intra-rater reliability. It showed a good accuracy for the documentation of changes of laryngeal anatomy and function after phonosurgery, similarly to the VALI form S. The 12 parameters of the VLSP form were judged "Slightly Important" in 28.3% of the samples, "Very Important" in 64.8% of the samples, "Not Difficult" in 73.1% of the samples. CONCLUSIONS: The results of the present study suggest that the VLSP form is comparable to the VALI form S for the evaluation of videolaryngostroboscopic parameters and is a valid, reliable and reproducible diagnostic tool. It can help voice clinicians in the evaluation of VLS examinations and it allows for a punctual assessment of modifications in laryngeal anatomy and function in pathological conditions and after phonosurgery.

Feasibility of Constant Work Rate Testing to Detect Exercise-Induced Laryngeal Obstruction.

INTRODUCTION: Exercise-induced laryngeal obstruction (EILO) is a condition in which laryngeal structures inappropriately obstruct the upper airway during exercise. The standard diagnostic test for EILO is the continuous laryngoscopy during exercise (CLE) test, usually performed with an incremental work rate protocol regardless of the nature of the triggering event. Typically, laryngeal obstruction occurs only briefly at the end of an incremental test, near peak work capacity. We aimed to investigate constant work rate (CWR) protocols for CLE testing to expand diagnostic test modalities and improve the understanding of EILO. METHODS: In this prospective, self-controlled feasibility study, 10 patients with EILO performed both an incremental and a CWR CLE test at 70%, 80%, and 90% of maximal exercise capacity. Laryngoscopic video data were recorded and compared, and we evaluated the ability of CWR to reproduce the symptoms and laryngeal obstruction seen in incremental testing. RESULTS: In 70%-90% of cases, CWR testing induced at least the same severity of obstruction as incremental testing and CLE scores remained comparable across test modalities. CWR at 70% allowed observation of laryngeal obstruction for a significantly longer duration than in incremental testing (158 s; 95% confidence interval, 25-291 s; P = 0.027). Dyspnea intensity appeared higher during CWR testing compared with incremental testing. CONCLUSIONS: Submaximal CWR CLE testing is feasible and able to induce EILO equivalent to the standard incremental CLE test. This is the first step toward tailored CLE exercise protocols, and further studies are now needed to establish the utility of CWR in clinical and research settings.

Transitions in Video Laryngoscope Technology to Improve First-Pass Success.

Prehospital intubation is a high-risk, relatively low frequency procedure. Provider experience plays a key role in first-pass success rates, especially in the setting of a difficult airway. While strong foundational knowledge is necessary to equip providers with an adequate understanding of intubation procedures and the skill set needed to manage a difficult airway, effective equipment may provide an extra boost in first-pass success for novice airway providers. First-pass success is correlated with decreased adverse events and should be maximized in the prehospital setting. After evaluating overall first-pass success of 66% to 83% from 2016 to 2020, AHN LifeFlight enacted changes in education, training, and video laryngoscopy equipment to successfully increase first-pass success to over 90%.

Neonatal intubation: what are we doing?

How and when the forces are applied during neonatal intubation are currently unknown. This study investigated the pattern of the applied forces by using sensorized laryngoscopes during the intubation process in a neonatal manikin. Nine users of direct laryngoscope and nine users of straight-blade video laryngoscope were included in a neonatal manikin study. During each procedure, relevant forces were measured using a force epiglottis sensor that was placed on the distal surface of the blade. The pattern of the applied forces could be divided into three sections. With the direct laryngoscope, the first section showed either a quick rise of the force or a discontinuous rise with several peaks; after reaching the maximum force, there was a sort of plateau followed by a quick drop of the applied forces. With the video laryngoscope, the first section showed a quick rise of the force; after reaching the maximum force, there was an irregular and heterogeneous plateau, followed by heterogeneous decreases of the applied forces. Moreover, less forces were recorded when using the video laryngoscope.    Conclusions: This neonatal manikin study identified three sections in the diagram of the forces applied during intubation, which likely mirrored the three main phases of intubation. Overall, the pattern of each section showed some differences in relation to the laryngoscope (direct or video) that was used during the procedure. These findings may provide useful insights for improving the understanding of the procedure. What is Known: • Neonatal intubation is a life-saving procedure that requires a skilled operator and may cause direct trauma to the tissues and precipitate adverse reactions. • Intubation with a videolaryngoscope requires less force than with a direct laryngoscope, but how and when the forces are applied during the whole neonatal intubation procedure are currently unknown. What is New: • Forces applied to the epiglottis during intubation can be divided into three sections: (i) an initial increase, (ii) a sort of plateau, and (iii) a decrease. • The pattern of each section shows some differences in relation to the laryngoscope (direct or videolaryngoscope) that is used during the procedure.

A Novel Intubation Technique: Bougie Introduction Via Ducanto Suction Catheter.

BACKGROUND: Airway management is a defining skill that demands mastery by emergency physicians. Airway emergencies pose considerable morbidity and mortality risks. Familiarity with, and mastery of, a variety of airway management approaches and equipment can prove invaluable for management of anatomically and physiologically difficult airways. CASE REPORT: A 67-year-old woman presented to a level II trauma after a motor vehicle collision. Emergency medical services reported left-sided injuries, including diminished breath sounds. She arrived in extremis with dyspnea and hypoxia refractory to supplemental oxygen. A portable chest x-ray study showed a considerable traumatic diaphragmatic hernia. Initial attempts at intubation via video laryngoscopy were unsuccessful. Difficulties were attributed to anatomic variation, possibly due to the traumatic diaphragmatic hernia, and hematemesis. The airway was repositioned after removal of a cervical collar and suction-assisted laryngoscopy airway decontamination was performed under video guidance. During airway decontamination, the tip of a DuCanto suction catheter (SSCOR) became located at the level of the vocal cords, prompting the decision to control the airway via utilization of the DuCanto suction catheter and a bougie. The suction tubing was disconnected, a bougie was inserted through the catheter, and the DuCanto was subsequently removed and replaced with a cuffed endotracheal tube. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: Airway emergencies are imminent life threats. Familiarity with a variety of tools and techniques allows for definitive airway management via primary, back-up, and contingency plans to secure anatomically or physiologically difficult airway.

Adult Laryngomalacia: A Scoping Review.

OBJECTIVE: This review sought to determine the characteristics of adults diagnosed with new onset laryngomalacia including airway symptoms, laryngoscopic findings, treatments, and outcomes. Moreover, we wanted to highlight suspected limitations in the literature. DATA SOURCES: Studies were identified through CINAHL, Cochrane Review, PubMed, and Scopus published between 1966 and 2023. REVIEW METHODS: The search was performed in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-analysis Extension for Scoping Reviews checklist by 2 independent investigators. A meta-analysis of proportions and continuous measures was conducted. RESULTS: Of the 1121 abstracts identified, 33 articles pertaining to laryngomalacia in the adult population were included. The most common presenting symptoms were stridor at rest (78.3%, 65.1-88.3) and dyspnea with exertion (83.8%, 64.8-96.3). The most suspected etiology was exercise-induced (86.0%, 69.4-95.5), and the most common description of laryngomalacia on visualization was collapse of supraglottic structures during exercise (93.3%, 79.0-99.1). Nonsurgical options were attempted in 87.0% (54.0-99.1), which included oral appliances, respiratory retraining, breathing techniques, and working with a speech pathologist. Surgical options were ultimately performed in 84.2% (75.0-91.0). Complete resolution of symptoms following therapy was seen in 61.9% (48.0-74.6). CONCLUSION: Adult onset laryngomalacia is difficult to characterize. It typically presents in patients during exercise, with neurological injury, or idiopathically. Surgical management can lead to improvement or complete resolution of symptoms. The need for a universal nomenclature is highlighted in this review, as it is inconsistently classified.

Videolaryngoscope versus conventional technique for insertion of a transesophageal echocardiography probe in intubated ICU patients (VIDLARECO trial): A randomized clinical trial.

BACKGROUND: Transesophageal echocardiogram probe insertion in intubated critically ill patients can be difficult, leading to complications, such as gastric bleeding or lesions in the oropharyngeal mucosa. We hypothesised that the use of a videolaryngoscope would facilitate the first attempt at insertion of the transesophageal echocardiogram probe and would decrease the incidence of complications compared to the conventional insertion technique. METHODS: In this clinical trial, patients were randomly assigned the insertion of a transesophageal echocardiogram probe using a videolaryngoscope or conventional technique. The primary outcome was the successful transesophageal echocardiogram probe insertion on the first attempt. The secondary outcomes included total success rate, number of insertion attempts, and incidence of pharyngeal complications. RESULTS: A total of 100 intubated critically ill patients were enrolled. The success rate of transesophageal echocardiogram probe insertion on the first attempt was higher in the videolaryngoscope group than in the conventional group (90% vs. 58%; absolute difference, 32%; 95% CI 16%-48%; p < 0.001). The overall success rate was higher in the videolaryngoscope group than in the conventional group (100% vs. 72%; absolute difference, 28%; 95% CI 16%-40%; p < 0.001). The incidence of pharyngeal mucosal injury was smaller in the videolaryngoscope group than in the conventional group (14% vs. 52%; absolute difference, 38%; 95% CI 21%-55%; p < 0.001). CONCLUSIONS: Our study showed that in intubated critically ill patients required transesophageal echocardiogram, the use of videolaryngoscope resulted in higher successful insertion on the first attempt with lower rate of complications when compared with the conventional insertion technique. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT04980976.

Topical Anaesthesia Using a Soft Mist Spray Device Allows Comfortable Awake Visualisation of the Airway via Self-Videolaryngoscopy in Volunteers.

Background: During endotracheal intubation, there is a 10% incidence of difficult laryngoscopy, which may result in serious complications. It is important to obtain as much information about the visibility of laryngeal structures before the patient is anaesthetised. Performing awake (video-) laryngoscopy on a patient is uncomfortable and can trigger gagging and coughing reflexes, making visualisation nearly impossible. The objective of this study is to evaluate the effectiveness of a soft mist spray device for airway anaesthesia during awake (video-) laryngoscopy. Methods: Twenty healthy volunteers inhaled through the Trachospray device, which was placed in their mouths. Two 2 mL syringes containing lidocaine at 4% were sprayed into the airway during inspiration. After several minutes, the subjects were asked to perform a videolaryngoscopy on themselves until the glottic structures and the vocal cords were visible. Upon completion of the procedure, all participants were asked to fill out a feedback form. Results: The duration of the videolaryngoscopy to visualisation of the vocal cords averaged 17 ± 13 s. After analysing the data, three distinct groups emerged as follows: Group 1 (70% of participants) showed no response, allowing for easy insertion of the videolaryngoscope. Group 2 (25% of participants) exhibited a light response but still permitted easy insertion and visualisation. One patient demonstrated a clear response with noticeable laryngeal contraction, requiring slightly more effort and discomfort for insertion. In 80% of the participants, the laryngeal structures were visualised according to Cormack-Lehane grade 1. All participants reported a high level of comfort, with an average rating of NRS 8. The anaesthesiologist assessed the level of anaesthesia as good to very good. No adverse events were observed. Conclusions: The Trachospray provided good, reliable, comfortable, and safe topical anaesthesia for awake videolaryngoscopy. This enables a direct visual assessment of the airway and may assist in making decisions regarding airway management for tracheal intubation.

Transitioning from Direct to Video Laryngoscopy during the COVID-19 Pandemic Was Associated with a Higher Endotracheal Intubation Success Rate.

OBJECTIVE: The objective of this study was to determine the effect of transitioning from direct laryngoscopy (DL) to video laryngoscopy (VL) on endotracheal intubation success overall and with enhanced precautions implemented during the COVID-19 pandemic. METHODS: We examined electronic transport records from Mayo Clinic Ambulance Service, a large advanced life support (ALS) provider serving rural, suburban, and urban areas in Minnesota and Wisconsin, USA. We determined the success of intubation attempts when using DL (March 10, 2018 to December 19, 2019), VL (December 20, 2019 to September 29, 2021), and VL with an enhanced COVID-19 guideline that restricted intubation to one attempt, performed by the most experienced clinician, who wore enhanced personal protective equipment (April 1 to December 18, 2020). Success rates at first attempt and after any attempt were assessed for association with type of laryngoscopy (VL vs DL) after adjusting for patient age group, patient weight, use of enhanced COVID-19 guideline, medical vs trauma patient, and ALS vs critical care clinician. A secondary analysis further adjusted for degree of glottic visualization. RESULTS: We identified 895 intubation attempts using DL and 893 intubation attempts using VL, which included 382 VL intubation attempts using the enhanced COVID-19 guideline. Success on first intubation attempt was 69.2% for encounters with DL, 82.9% overall with VL, and 83.2% with VL and enhanced COVID-19 protocols (DL vs overall VL: p < 0.001; COVID-19 vs non-COVID VL: p = 0.86). In multivariable analysis, use of VL was associate with higher odds of successful intubation on first attempt (odds ratio, 2.28; 95%CI, 1.73-3.01; p < 0.001) and on any attempt (odds ratio, 2.16; 95%CI, 1.58-2.96; p < 0.001) compared with DL. Inclusion of glottic visualization in the model resulted in a nonsignificant association between laryngoscopy type and successful first intubation (p = 0.41) and a significant association with the degree of glottic visualization (p < 0.001). CONCLUSIONS: VL is designed to improve glottic visualization. The use of VL by a large, U.S. multistate ALS ambulance service was associated with increased odds of successful first-pass and overall attempted intubation, which was mediated by better visualization of the glottis. COVID-19 protocols were not associated with success rates.

Correlation of narrow-band imaging findings using the Ni and European Laryngeal Society classification systems during in-office flexible laryngoscopy with histopathology.

OBJECTIVE: This study used the European Laryngeal Society (2016) and Ni (2011 and 2019) classifications for narrow-band imaging and correlated the findings with histopathology. METHODS: Retrospective analysis was conducted by retrieving data of patients who underwent micro-laryngoscopy for suspicious glottic lesions. The narrow-band imaging findings were classified using both classification systems. Retrieved histopathology report findings were correlated with narrow-band imaging data. RESULTS: Using the European Laryngeal Society and Ni classifications, 37 (69.8 per cent) and 35 (66 per cent) patients, respectively, were suspected to have malignant lesions. Upon histopathology, 37 (69.8 per cent) lesions were malignant. Sensitivity, specificity, positive predictive value, negative predictive value and accuracy using the European Laryngeal Society classification were 91.9 per cent, 81.3 per cent, 91.9 per cent, 81.3 per cent and 88.7 per cent, and using the Ni classification were 91.9 per cent, 93.8 per cent, 97.1 per cent, 83.3 per cent and 92.5 per cent, respectively. CONCLUSION: The Ni classification had better specificity and accuracy. The European Laryngeal Society classification is simple to use and may serve as a useful screening tool. For optimum results, both European Laryngeal Society and Ni classifications may be used together, in that order.