Bedside preoperative predictors of difficult laryngeal exposure in microlaryngeal surgery

PURPOSE

Successful microlaryngeal surgery relies on an adequate laryngeal exposure. Recognizing the likelihood of challenging exposure prior to microlaryngeal surgery may assist in selecting the appropriate surgical approach and even prompt consideration of alternative treatment options. We aim to apply the mini-Laryngoscore, a preoperative assessment tool, to our study population and incorporate novel variables to optimize the prediction model.

METHODS

This single-center prospective cohort study included 80 consecutive patients undergoing elective microlaryngeal surgery, from January 1, to June 30, 2023. Each patient underwent a presurgical evaluation of 15 parameters and an intraoperative scoring of the anterior commissure visualization. These parameters were assessed for their association with difficult laryngeal exposure, using multiple logistic regression analysis. We created a novel prediction model for DLE and compared it with the existing model, the mini-Laryngoscore.

RESULTS

Out of 80 patients, 24 (30%) patients had difficult laryngeal exposure, including 3 cases (3.8%) in which visualization of the anterior commissure was not possible. A large neck diameter (OR, 1.4; CI 1.1-1.9) and the presence of upper teeth (OR, 8.9; CI 1.3-62.8) were independent risk factors for a difficult laryngeal exposure, while a larger interincisors gap was the only independent protector factor (OR, 0.3; CI 0.1-0.8). The logistic regression model combining these three independent risk factors displayed a high discriminative value AUC = 0.89 (CI 0.81-0.97). The predictive performance of the mini-Laryngoscore was 0.73 (CI 0.62-0.85).

CONCLUSION

Combining two parameters from the mini-Laryngoscore (upper jaw dental state and interincisors gap distance) with neck circumference measurement can accurately predict the risk of difficult laryngeal exposure.

The influence of clinical experience on reliable evaluation of pharyngeal and laryngeal lesions: comparison of high-definition laryngoscopy using narrow band imaging with fibre-optic laryngoscopy

BACKGROUND

Fibre-optic laryngoscopy is still widely used in daily clinical practice; however, high-definition laryngoscopy using narrow band imaging could be more reliable in characterising pharyngeal and laryngeal lesions.

METHODS

Endoscopic videos were assessed in a tertiary referral hospital by 12 observers with different levels of clinical experience. Thirty pairs of high-definition laryngoscopy with narrow band imaging and fibre-optic laryngoscopy videos were judged twice, with an interval of two to four weeks, in a random order. Inter- and intra-observer reliability, sensitivity and specificity were calculated in terms of detecting a malignant lesion and a specific histological entity, for beginners, trained observers and experts.

RESULTS

Using high-definition laryngoscopy with narrow band imaging, inter-observer reliability for detecting malignant lesions increased from moderate to substantial in trained observers and experts (high-definition laryngoscopy with narrow band imaging κ = 0.66 and κ = 0.77 vs fibre-optic laryngoscopy κ = 0.51 and κ = 0.56, for trained observers and experts respectively) and sensitivity increased by 16 per cent.

CONCLUSION

Inter-observer reliability increased with the level of clinical experience, especially when using high-definition laryngoscopy with narrow band imaging.

Body positioning-related laryngeal narrowing pattern and expiratory mechanical constraints in advanced chronic obstructive pulmonary disease: A case report

We previously reported that laryngeal widening led to improved exercise tolerance in COPD. However, it is not clear whether laryngeal narrowing occurs as a compensatory response to tracheal movement or is affected by posture. Here, we report the case of an advanced COPD patient whose more prolonged expiration in a head-forward leaning position compared with that in a neck-extended position occurred with an excessive duration of severe laryngeal narrowing without tracheal obstruction, which led to exercise intolerance with expiratory mechanical constraints. This case provided useful insights into the regulation of the upper airway with body positioning for improving exercise tolerance.

Utility of laryngoscopy in liver failure

PURPOSE

To determine the utility of laryngoscopy in the evaluation of liver transplant patients.

METHODS

This study is a single center retrospective cohort review of patients with a diagnosis of liver failure who underwent laryngoscopy or stroboscopy exam as part of a pre-transplant evaluation from 1/1/2010 to 12/31/2022. Patients were identified using ICD 9 and 10 codes for liver failure and CPT codes for flexible laryngoscopy and stroboscopy. Only patients who underwent preoperative liver transplant evaluation were included. Demographic data was collected. Cohort analysis between patients who did or did not undergo further diagnostic intervention was undertaken.

RESULTS

1824 patients were identified. 243 of these patients underwent pre-transplant laryngoscopy or stroboscopy. 26 of the 243 (10.7 %) patients had further diagnostic work up for findings during laryngoscopy, stroboscopy, or head and neck examination. There was one patient who was found to have head and neck cancer and was excluded from the transplant list until this was treated.

CONCLUSIONS

Otolaryngologic evaluation of liver transplant patients may be beneficial to identify head and neck pathology.

Case report

INTRODUCTION

Difficult intubation is the situation when a skilled anesthetist has difficulties to manage airway using face mask, laryngoscopy, supraglottic device, tracheal intubation, surgery. Videolaryngoscope and flexible fibroscope (FFS) represent valid alternatives for difficult airway management, with some limitations. However, literature lacks of studies about the efficacy of the combined use of videolaryngoscope and FFS.

CASE REPORT

We report a case of a man, with glottic lesion, who needs surgery under general anesthesia. Anesthesiologic pre-operative evaluation revealed that he's a difficult intubation case. So, in a supine position, intubation was performed on first attempt by videolaryngoscope combined with FFS. On post-op, no signs of injuries due to intubation have been found.

DISCUSSION

In 2022, the American Society of Anesthesiologists defined the guidelines to manage difficult intubation: based on patient' anatomical and clinical feature and anesthetist' skills, several intubation procedures could be used. Each procedure has pros and cons.

CONCLUSION

It's the first case of anticipated difficult intubation in adult man that was intubated under general anesthesia by using videolaryngoscope combined with FFS. We demonstrated that this procedure is safe and useful in case of difficult airway and recommended in case of laryngeal lesions that hinder the visualization of glottic plane.

Laryngoscopy-based scoring system for the diagnosis of vocal fold leukoplakia

OBJECTIVE

To propose a scoring system based on laryngoscopic characteristics for the differential diagnosis of benign and malignant vocal fold leukoplakia.

METHODS

Laryngoscopic images from 200 vocal fold leukoplakia cases were retrospectively analysed. The laryngoscopic signs of benign and malignant vocal fold leukoplakia were compared, and statistically significant features were assigned and accumulated to establish the leukoplakia finding score.

RESULTS

A total of five indicators associated with malignant vocal fold leukoplakia were included to construct the leukoplakia finding score, with a possible range of 0-10 points. A score of 6 points or more was indicative of a diagnosis of malignant vocal fold leukoplakia. The sensitivity, specificity and accuracy values of the leukoplakia finding score were 93.8 per cent, 83.6 per cent and 86.0 per cent, respectively. The consistency in the leukoplakia finding score obtained by different laryngologists was strong (kappa = 0.809).

CONCLUSION

This scoring system based on laryngoscopic characteristics has high diagnostic value for distinguishing benign and malignant vocal fold leukoplakia.

Sex Disparities in Applied Force on Maxillary Incisors Among Novices During Laryngoscopy Using a High-Fidelity Simulator: A Prospective Observational Study

Endotracheal intubation (ETI) is a common and crucial intervention. Whether the performance of ETI differs according to the sex of the laryngoscopist remains unclear. The aim of this study was to assess sex disparities in markers of ETI performance among novices using a high-fidelity simulator. This prospective observational study was conducted from April 2017 to March 2019 in a public medical university. In total, 209 medical students (4th and 5th grade) without clinical ETI experience were recruited. Of the 209 students, 64 (30.6%) were female. The participants used either a Macintosh direct laryngoscope or C-MAC video laryngoscope in combination with a stylet or gum-elastic bougie to perform ETI on a high-fidelity simulator. The primary endpoint was the maximum force applied on the maxillary incisors during laryngoscopy. The secondary endpoint was the time to ETI. The implanted sensors in the simulator automatically quantified the force and time to ETI. The maximum force applied on the maxillary incisors was approximately 30% lower in the male than female group for all laryngoscopes and intubation aids examined (all P < 0.001). Similarly, the time to ETI was approximately 10% faster in the male than female group regardless of the types of laryngoscopes and intubation aids used (all P < 0.05). In this study, male sex was associated with a lower maximum force applied on the maxillary incisors during both direct and indirect laryngoscopy performed by novices. A clinical study focusing on sex differences in ETI performance is needed to validate our findings.

Squamous Cell Carcinoma of the Supraglottis Presenting as Hoarseness

Hoarseness is a well-known condition in primary care offices, with over 1% of primary care visits secondary to this ailment.1 The most common causes are acute laryngitis (40%), functional dysphonia (30%), benign and malignant tumors (2.2 to 30%), neurogenic factors such as vocal cord paralysis (8%), physiological aging (2%), and psychogenic factors (2.2%). Most of these cases are secondary to viral infections and do not require antibiotics on most occasions. These viral infections subside after 1 to 2 weeks, and in the case of persistent hoarseness (above 4 weeks) the American Academy of Otolaryngology recommends direct visualization with a laryngoscopy before treatment with proton pump inhibitors, antibiotics, or steroids. Our patient presented with prolonged hoarseness (greater than eight weeks) but had a quick turn around time interval between primary care visit and laryngoscopy evaluation (less than 2 weeks). This led to her diagnosis and treatment with chemo and radiation therapy within three months of diagnosis with Squamous Cell Carcinoma of the Supraglottis. The Primary care physician serves as the number one point of visitation by sufferers of hoarseness. It is important that they are knowledgeable and up to date with recommendations and guidelines for managing this condition, as unwarranted delay can affect overall outcome on the part of the patient. This is especially important in patients such as ours with high risk factors including Nicotine dependence, alcohol use, asbestos exposure, and HPV infection.

Vision-Based Assistance for Vocal Fold Identification in Laryngoscopy with Knowledge Distillation

Laryngoscopy images play a vital role in merging computer vision and otorhinolaryngology research. However, limited studies offer laryngeal datasets for comparative evaluation. Hence, this study introduces a novel dataset focusing on vocal fold images. Additionally, we propose a lightweight network utilizing knowledge distillation, with our student model achieving around 98.4% accuracy-comparable to the original EfficientNetB1 while reducing model weights by up to 88%. We also present an AI-assisted smartphone solution, enabling a portable and intelligent laryngoscopy system that aids laryngoscopists in efficiently targeting vocal fold areas for observation and diagnosis. To sum up, our contribution includes a laryngeal image dataset and a compressed version of the efficient model, suitable for handheld laryngoscopy devices.

Video versus direct laryngoscopy in critically ill patients: an updated systematic review and meta-analysis of randomized controlled trials

BACKGROUND

The utilization of video laryngoscopy (VL) has demonstrated superiority over direct laryngoscopy (DL) for intubation in surgical settings. However, its effectiveness in the intensive care unit and emergency department settings remains uncertain.

METHODS

We systematically searched PubMed, Embase, Cochrane, and ClinicalTrials.gov databases for randomized controlled trials (RCTs) comparing VL versus DL in critically ill patients. Critical setting was defined as emergency department and intensive care unit. This systematic review and meta-analysis followed Cochrane and PRISMA recommendations. R version 4.3.1 was used for statistical analysis and heterogeneity was examined with I2 statistics. All outcomes were submitted to random-effect models.

RESULTS

Our meta-analysis of 14 RCTs, compromising 3981 patients assigned to VL (n = 2002) or DL (n = 1979). Compared with DL, VL significantly increased successful intubations on the first attempt (RR 1.12; 95% CI 1.04-1.20; p < 0.01; I2 = 82%). Regarding adverse events, VL reduced the number of esophageal intubations (RR 0.44; 95% CI 0.24-0.80; p < 0.01; I2 = 0%) and incidence of aspiration episodes (RR 0.63; 95% CI 0.41-0.96; p = 0.03; I2 = 0%) compared to DL.

CONCLUSION

VL is a more effective and safer strategy compared with DL for increasing successful intubations on the first attempt and reducing esophageal intubations in critically ill patients. Our findings support the routine use of VL in critically ill patients. Registration CRD42023439685 https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42023439685 . Registered 6 July 2023.

Digital Videokymography: Analysis of Glottal Closure in Adults

INTRODUCTION

High-speed videolaryngoscopy and quantitative analysis of laryngeal images are relevant in accurately diagnosing vocal fold closure patterns.

OBJECTIVE

To analyze the parameters of digital videokymography obtained through high-speed videolaryngoscopy in women and men with complete and incomplete glottal closure, and posterior glottal chink.

METHODS

We conducted an observational, analytical, cross-sectional study with data from 65 adults, which we divided into groups according to sex and glottal closure. Digital videokymography parameters were analyzed using an image-processing program. The Anderson-Darling and Mann-Whitney U tests were used to verify sample normality and compare videokymography parameters between groups, respectively. The significance level was set at 5%.

RESULTS

Among 65 laryngeal images, 20 each were from women with complete and incomplete glottal closure, and 20 and 5 were from men with complete and incomplete glottal closure, respectively. Considering the clinical relevance of the evaluated data, groups of 11 women and 4 men with posterior glottal chink were compared with sex-similar groups with complete glottal closure. Digital videokymography showed a lower maximum and mean vocal fold opening in women with incomplete glottal closure, and a lower dominant left vocal fold-opening amplitude and higher dominant frequency of bilateral vocal fold opening in men with incomplete glottal closure. It also showed a lower closed phase percentage in the posterior region for women and men, with higher closed phase percentage in the anterior and middle regions in women. Both groups with posterior glottal chink showed similar results.

CONCLUSION

Incomplete glottal closure may interfere with the results of the digital videokymography parameters, with higher impact on the posterior vocal fold region in males and the middle and anterior vocal fold regions in females.

Recommendations from the Brazilian Society of Anesthesiology (SBA) for difficult airway management in pediatric care

Difficult airway management in pediatrics during anesthesia represents a major challenge, requiring a careful approach, advanced technical expertise, and accurate protocols. The task force of the Brazilian Society of Anesthesiology (SBA) presents a report containing updated recommendations for the management of difficult airways in children and neonates. These recommendations have been developed based on the consensus of a panel of experts, with the objective of offering strategies to overcome challenges during airway management in pediatric patients. Grounded in evidence published in international guidelines and expert opinions, the report highlights crucial steps for the appropriate management of difficult airways in pediatrics, encompassing assessment, preparation, positioning, pre-oxygenation, minimizing trauma, and, paramountly, the maintenance of arterial oxygenation. The report also delves into additional strategies involving the use of advanced tools, such as video laryngoscopy, flexible intubating bronchoscopy, and supraglottic devices. Emphasis is placed on the simplicity of implementing the outlined recommendations, with a focus on the significance of continuous education, training through realistic simulations, and familiarity with the latest available technologies. These practices are deemed essential to ensure procedural safety and contribute to the enhancement of anesthesia outcomes in pediatrics.

Recommendations from the Brazilian Society of Anesthesiology (SBA) for difficult airway management in adults

Difficult airway management represents a major challenge, requiring a careful approach, advanced technical expertise, and accurate protocols. The task force of the Brazilian Society of Anesthesiology (SBA) presents a report with updated recommendations for the management of difficult airway in adults. These recommendations were developed based on the consensus of a group of expert anesthesiologists, aiming to provide strategies for managing difficulties during tracheal intubation. They are based on evidence published in international guidelines and opinions of experts. The report underlines the essential steps for proper difficult airway management, encompassing assessment, preparation, positioning, pre-oxygenation, minimizing trauma, and maintaining arterial oxygenation. Additional strategies for using advanced tools, such as video laryngoscopy, flexible bronchoscopy, and supraglottic devices, are discussed. The report considers recent advances in understanding crisis management, and the implementation seeks to further patient safety and improve clinical outcomes. The recommendations are outlined to be uncomplicated and easy to implement. The report underscores the importance of ongoing education, training in realistic simulations, and familiarity with the latest technologies available.

MONTH Score in Predicting Difficult Intubations in Emergency Department; a Prognostic Accuracy Study

Introduction

MONTH Difficult Laryngoscopy Score was developed for effectively identifying difficult intubations in the emergency department (ED). This study aimed to evaluate the accuracy of MONTH Score in predicting difficult intubations in ED.

Methods

We prospectively collected data on all patients undergoing intubation in the ED of Ramathibodi Hospital, Bangkok, Thailand. The screening performance characteristics of the MONTH score in identifying the difficult intubation in ED were analyzed. All data were analyzed using STATA software version 18.0.

Results

324 intubated patients with the median age of 73 (63-82) years were studied (63.58% male). The proportion of difficult intubations was 19.44%. The sensitivity and specificity of MONTH in predicting difficult intubations were 74.6% (95% CI: 61.6%-85.0%) and 92.8% (95% CI: 89.0%-95.6%), respectively. These measures in subgroup of patients with Intubation Difficulty Scale (IDS) score ≥ 6 were 44.1% (95%CI: 31.2-57.6) and 98.5% (95% CI: 96.2%- 99.6%), respectively. The area under the receiver operation characteristic (ROC) curve of MONTH in predicting difficult intubations was 0.895 (95% CI: 0.856- 0.926).

Conclusions

It seems that the MONTH Difficult Laryngoscopy Score could be considered as a tool with high specificity and positive predictive values in identifying cases with difficult intubations in ED.

Nebulized dexmedetomidine for attenuating hemodynamic response to laryngoscopy and endotracheal intubation in adult patients undergoing surgeries under general anaesthesia: a systematic review and meta-analysis of randomized controlled trials

BACKGROUND

Sympathetic stimulation associated with laryngoscopy and endotracheal intubation (ETI) may lead to adverse cardio-/cerebro-vascular events in susceptible patients. Nebulization is a novel route for dexmedetomidine administration providing a large surface area for absorption while avoiding bradycardia and hypotension associated with intravenous route. We aimed to evaluate the efficacy and safety of dexmedetomidine nebulization for attenuating hemodynamic response to ETI in adult patients undergoing surgery under general anaesthesia.

METHODS

This systematic review was registered prospectively in the International Prospective Register of Systematic Reviews (CRD42023403624). PubMed, Embase (OvidSP), Cochrane library, Scopus (Elsevier), Web of Science (Clarivate) and Google Scholar were systematically searched from database inception until March 31, 2023. Two reviewers independently screened titles, abstracts and then full text against pre-specified eligibility criteria. Randomized controlled trials (RCTs) assessing effect of dexmedetomidine nebulization on hemodynamic response to ETI in adult patients undergoing surgeries under general anaesthesia were included. All studies reporting heart rate and systolic blood pressure at baseline and various time points after ETI were included. A pre-piloted data extraction form, Cochrane revised risk-of-bias tool (ROB 2) tool, GRADE approach and RevMan 5.4.1 (Cochrane Collaboration, Copenhagen, Denmark) were used for data extraction, risk of bias assessment, rating certainty of evidence and data synthesis respectively. Mean difference and relative risk with 95% Confidence Interval (CI) were used for continuous and dichotomous variables respectively.

RESULTS

Six RCTs randomized 480 patients with ASA I/II patients aged < 60 years of age and undergoing elective surgeries to receive either dexmedetomidine (n = 240) or saline nebulization (n = 240). Except for one RCT which used 2 μg/kg, all other RCTs used dexmedetomidine dose of 1 μg /kg. Heart rate, systolic, diastolic and mean blood pressure were significantly lower in the dexmedetomidine group at all the measured time points after laryngoscopy and ETI with the only exception being systolic blood pressure at 3 min [mean difference -13.86 (95% CI -30.01 to 2.99), p = 0.09]. Bradycardia and hypotension as adverse effects were absent across the included studies. However, only one-third of the included studies had a low risk of bias and strength of evidence was very low according to the GRADE assessment.

CONCLUSIONS

Compared to placebo, premedication with dexmedetomidine nebulization was associated with lower HR and BP following ETI without any risk of bradycardia and hypotension. However, the strength of evidence was very poor and came from just one country. Future well designed and conducted studies in different populations are warranted.

TRIAL REGISTRATION

PROSPERO Registration number: CRD42023403624.

A taxonomy of key performance errors for emergency intubation

STUDY OBJECTIVE

Currently the videographic review of emergency intubations is an unstructured, qualitative process. We created a taxonomy of errors that impede the optimal procedural performance of emergency intubation.

METHODS

This was a prospective, observational, study reviewing a convenience sample of deidentified laryngoscopy recordings of emergency department intubations that were qualitatively flagged before the study as demonstrating suboptimal technique. These videos were coded for the presence of 13 predetermined performance errors. Our primary outcome was the incidence of each of these specified errors during emergency intubation. Errors fell into 3 categories: errors of structure recognition during laryngoscope insertion, errors of vallecula manipulation, and errors of device delivery.

RESULTS

A total of 100 intubation attempts were reviewed. The most common error was inadequate lifting force with the blade tip in the vallecula which lowered the percent of glottic opening, occurring in 45% of the attempts. The least common performance error was the premature removal of the laryngoscope during bougie placement, occurring in only 9% of the videos.

CONCLUSION

We developed a taxonomy of 13 performance errors of laryngoscopy. Further study is warranted to determine how to best incorporate these into emergency airway training and the airway review process.

Effectiveness of ultrasonic measurement for the hyomental distance and distance from skin to epiglottis in predicting difficult laryngoscopy in children

OBJECTIVES

Studies have shown that some ultrasonic indicators can predict difficult airways in adults to an extent. However, whether ultrasonic parameters can be used to predict difficult airways in children is unclear. This study investigated the predictive value of several ultrasonic indices for difficult laryngoscopy (DL) in children.

METHODS

Pediatric patients aged 5 to 12 years who underwent endotracheal intubation under general anesthesia were enrolled. The hyomental distance in the extended position (HMDE), tongue thickness, midsagittal tongue cross-sectional area, tongue width, and distance from skin to epiglottis (DSE) were measured by ultrasound before anesthesia. The study end point was DL. The receiver operating characteristic curve was used to evaluate the predictive value of each parameter.

RESULTS

Three hundred and ten children were included in the final analysis, and fifteen (4.8%) children had DL. The shortened HMDE assessed by ultrasound could help identify children aged 5 to 12 years with DL (5-8 years: area under the curve (AUC) 0.74, sensitivity 0.88, specificity 0.60; 9-12 years: AUC 0.72, sensitivity 0.71, specificity 0.83). An increased DSE could help identify children aged 5 to 8 years with DL (AUC 0.76, sensitivity 0.88, specificity 0.69).

CONCLUSIONS

Ultrasonic measurement of the HMDE can be used to predict DL in children aged 5 to 12 years. The DSE measured by ultrasound can be used to predict DL in children aged 5 to 8 years.

CLINICAL RELEVANCE STATEMENT

The hyomental distance and the distance from skin to epiglottis measured by ultrasound can be used to predict difficult laryngoscopy in children, which can help reduce serious complications caused by unanticipated difficult airways in children during anesthesia.

KEY POINTS

• Ultrasonic measurement of the hyomental distance in the extended position may be an effective predictor of difficult laryngoscopy in children aged 5 to 12 years. • The distance from skin to epiglottis measured by ultrasound can be used to predict difficult laryngoscopy in children aged 5 to 8 years. • Preoperative airway assessment using ultrasound can be effectively applied in children and has a great application prospect.

An Old Myth: Prediction of the Correct Singing Voice Classification. True or not?

OBJECTIVE

Predicting the correct singing voice classification based on laryngoscopy is an old myth. The aim of this study was to evaluate if a professional phoniatrician/laryngologist can predict the correct singing voice classification only from laryngoscopy and to analyze different anatomical parameters between professional sopranos and altos to determine whether a multivariate analysis of anatomical parameters can predict the singing register.

STUDY DESIGN

Prospective study METHODS: We included 49 professional female singers (25 sopranos, 24 altos). Laryngoscopic images were shown to professional phoniatricians/laryngologists to rate whether it they show a soprano or an alto. In addition, a high-resolution computer tomography (HRCT) scan was performed during singing of ƒ0 by each singer. DICOM scan data were rendered and 3D-visualized using the software MIMICS. In all singers, we measured the length of the vocal folds of the glottis, the distance from the anterior commissure orthogonally to the vertebral spine, and the antero-posterior distance of the subglottis/trachea 1 cm and 2 cm below the glottis. We also measured the length and volume of the resonance space.

RESULTS

It was not possible to predict the singing voice classification only from laryngoscopy. In the HRCT images, sopranos had significantly shorter vocal folds, a shorter glottal length, a shorter distance from the anterior commissure to the spine, and a shorter resonance space. When combining all parameters, the chance of correctly predicting a soprano was 74.1% and an alto 68.2%.

CONCLUSION

Although there are anatomical differences between sopranos and altos, prediction of the singing voice classification from laryngoscopy or HRCT is not reliable enough for clinical use.

Can Transcutaneous Laryngeal Ultrasonography Systematically Quantify Vocal Fold Movement?-A Feasibility Study

OBJECTIVES

Several studies have assessed adult vocal fold movement using transcutaneous laryngeal ultrasonography (TLUSG) during the perioperative period of thyroidectomy. However, the movement was not objectively quantified. This study aimed to provide a feasible and objective method for assessing vocal fold movement using TLUSG.

STUDY DESIGN

Feasibility study.

METHODS

TLUSG was performed during calm breathing and breath-holding in healthy adult volunteers. The morphology and anatomy of the larynx were observed and measured using an ultrasonic self-contained measurement function. At the end of the calm inspiratory and breath-holding phases, vocal fold angle, vocal fold length, distance from vocal process to the midline, distance from anterior vocal commissure to arytenoid cartilage, distance from false vocal fold to the midline, and distance from the anterior horn of thyroid cartilage to false vocal fold were measured. Data were analyzed using a t test (significance <0.05).

RESULTS

The ultrasonic images were satisfactory in all 40 healthy adult volunteers (age 19-35 years; body mass index 18.55-23.93 kg/m2; 20 men and 20 women). There were no significant differences in all laryngeal parameters between the left and right sides in both phases (P > 0.05). Moreover, all differences in laryngeal parameters between the end of the calm inspiratory phase and the breath-holding phase were statistically significant (P < 0.05), regardless of sex.

CONCLUSION

The relevant positional parameters of the vocal fold, arytenoid cartilage, and false vocal fold and their differences before and after vocal fold movement in healthy adult volunteers can be obtained objectively using TLUSG.

Relationships Between Laryngoscopic Analysis Metrics of Supraglottic Compression and Vocal Effort in Primary Muscle Tension Dysphonia

PURPOSE

Supraglottic compression is thought to underlie vocal effort in patients with primary muscle tension dysphonia (pMTD). However, the relationship between supraglottic compression and vocal effort in this clinical population remains unclear. Gold standard laryngoscopic assessment metrics for supraglottic compression are also lacking. The goals of this study were to identify metrics proposed in the literature that could distinguish patients diagnosed with pMTD from typical voice users and determine their relationships to the vocal effort.

METHODS

Flexible laryngeal endoscopy was performed on 50 participants (25 pMTD, 25 controls). The presence of supraglottic compression was characterized using a categorical (nominal) scale and severity was quantified on ordinal and continuous scales. The three laryngoscopic metrics were correlated with self-perceived ratings of vocal effort on a 100 mm visual analog scale.

RESULTS

Inter-rater reliability was strongest for the continuous scale (P's < 0.0001) compared to categorical (P's < 0.001) and ordinal (P's < 0.001) scales. The presence of different supraglottic compression patterns varied in both groups, and there were no significant group differences on categorical (P's > 0.05) scales. Mediolateral (M-L) supraglottic compression was significantly greater in the pMTD group (P < 0.0001), and anteroposterior (A-P) compression was significantly greater in the control group (P = 0.001) using continuous scales. There were no significant relationships between any of the three laryngoscopic metric types and vocal effort ratings (P's > 0.05), except for a significantly positive relationship between anterior-posterior compression on the ordinal scale and vocal effort in the control group (P = 0.047).

CONCLUSIONS

Continuous scales are reliable and valid for distinguishing individuals with pMTD from those without voice disorders, especially occupational voice users. M-L supraglottic compression may be a better indicator of pMTD than A-P compression. However, the poor correlation between supraglottic compression and vocal effort suggests that one may not influence the other. Future studies should focus on other mechanisms underlying vocal effort in patients with pMTD.

Perinatal management of the anticipated difficult airway

The ex-utero intrapartum treatment (EXIT) procedure was originally developed to reverse tracheal occlusion in fetuses with severe congenital diaphragmatic hernia that underwent fetal tracheal occlusion. The EXIT procedure has since been applied to a wide range of indications, but the primary indication remains securing a patent airway and providing respiratory support in fetuses with anticipated difficult airways. The authors review perinatal management of the anticipated difficult airway and their single-institution's experience with the EXIT procedure.

The history of neonatal intubation

Interest in 'resurrecting' the lifeless by supporting breathing has been described since ancient times. For centuries, methods of resuscitating animals, then humans and specifically the 'lifeless' neonate were debated and discussed. Over time, with experimentation and worldwide collaboration, endotracheal tubes and laryngoscopes specific to the newborn were created and their use refined. This historical work has meant that today, the neonatal community focuses on refining the science and the art of intubation for the benefit of the newborn; who, where, when and how to intubate, with what devices and medications, bringing about significant change in the area of neonatal intubation. Recent work has focused on alternatives to neonatal intubation as the risks of endotracheal intubation and mechanical ventilation have become clearer. Appreciating the history of neonatal intubation and its (somewhat cyclical) changes over time can show us how far we've come and how far we can still go in the resuscitation and respiratory support of newborns.

Videolaryngoscopy in neonatal clinical care

Endotracheal intubation is a life-saving procedure for many newborns. Historically, it has been achieved by obtaining an airway view through the mouth via direct laryngoscopy. It is a skill that takes time and practice to achieve proficiency. Increasing evidence for the benefit of videolaryngoscopy in adults and the new development of technology has allowed videolaryngoscopy to become a reality in neonatal care. Studies have examined its use as both a technique to improve intubation safety and success, and as a training tool for those learning the skill in this vulnerable population. We present the current evidence for videolaryngoscopy in neonates in different settings where intubation may be required, in addition to exploring the challenges and practicalities of implementing this technique into clinical practice.

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.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSION

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

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.

Head and neck positioning for out-of-theatre intubation during the COVID-19 pandemic

The COVID-19 pandemic has brought with it a large number of challenges for healthcare professionals including intubation safety in out-of-theatre environments. An important aspect of this topic is the optimisation of a patient's head and neck position prior to laryngoscopy which can be challenging when a pillow cannot be located. As a result, the authors compared how well the sniffing position (35o neck flexion and 15o head extension) could be reached using pillows or other novel head supports. The resulting data demonstrated that a 1-litre pressure bag and two 1-litre saline bags achieved the most accurate position.

The Occurrence of Laryngeal Pathologies in a Treatment-Seeking Pediatric Population

OBJECTIVES

The purpose of this study was to 1) describe the age- and sex-specific occurrence of laryngeal pathologies in a treatment-seeking pediatric population in the voice unit of Ghent University Hospital, Belgium, and 2) describe this population in terms of vocal parameters, vocal complaints, influencing factors, and treatment history and recommendation.

STUDY DESIGN

Retrospective, observational study.

METHODS

All patient records were analyzed for children (0-18 years) who consulted the ear, nose, and throat department of Ghent University Hospital for the first time between July 2015 and June 2021 with complaints of dysphonia. In total, 103 children (66 males, 37 females) with a mean age of 10.01 years (SD: 3.4, range 3.93-17.96) were included in this study. Laryngeal pathology was diagnosed using a flexible videolaryngo(strobo)scopy. The influence of age and sex on laryngeal etiology (organic/functional voice disorder) was examined using a Welch-modified t test and a Fisher's exact test, respectively.

RESULTS

Organic lesions were observed in 77.7% of the participants, with vocal fold nodules (VFNs) being the most common diagnosis (66.0%). A functional voice disorder was diagnosed in 22.3% of the children. Children with a functional voice disorder are significantly older than children with an organic voice disorder. There was no statistically significant difference between males and females in laryngeal etiology. Mean dysphonia severity index was -2.7 (SD: 3.2, range -9.3 to +3.7), the mean acoustic voice quality index 4.70 (SD: 1.5, range 2.35-8.27), and the mean pediatric voice handicap index 29.8 (SD: 13.6, range 5-60). The occurrence of vocal misuse was mentioned in 80.6% of the patient records.

CONCLUSION

Organic voice disorders, especially VFNs, are predominant in treatment-seeking children with dysphonia. Functional voice disorders become more common with increasing age during childhood. A disordered vocal quality, reduced vocal capabilities and reduced voice-related quality of life were found.

Prediction of difficult laryngoscopy / difficult intubation cases using upper airway ultrasound measurements in emergency department: a prospective observational study

INTRODUCTION

Difficult laryngoscopy and intubation are serious problems among critically ill patients in emergency department (ED) so utility of a rapid, accurate and noninvasive method for predicting of these patients are necessary. Ultrasonography has been recently used in this regard and this study was conducted to investigate the correlation of some introduced upper airway ultrasound parameters with difficult laryngoscopy / difficult intubation in patients referred to the ED.

METHOD

In this prospective observational study all patients ≥ 18-year-old who had an indication for rapid sequence intubation (RSI) were included. Ultrasound parameters including Hyoid Bone Visibility (HBV), Distance from Skin to Hyoid Bone (DSHB), Distance from Skin to Vocal Cords (DSVC), Distance from Skin to Thyroid Isthmus (DSTI), and Distance between Arytenoids Cartilages (DBAC) were measured in all cases. The patients underwent RSI and thereafter the patients' baseline characteristics, Cormack-Lehane grade, number of attempted laryngoscopy were recorded in a pre-prepared check list and compared with measured ultrasound parameters. The "difficult laryngoscopy" was defined as Cormack-Lehane classification grades III/IV; and need for more than 3 intubation attempts was considered as "difficult intubation".

RESULTS

One hundred and twenty-three patients (52% male) were included of whom 10 patients (8.1%) were categorized as difficult laryngoscopy cases; and just 4 (3.3%) cases underwent more than 3 laryngoscopy attempts who considered as difficult intubation cases. The mean age of the patients in non-difficult and difficult intubation groups were 69.2 ± 15.16 and 68.77 ± 17.37 years, respectively (p > 0.05). There was no significant relationship between difficult laryngoscopy and HBV (p = 0.381) but has significant correlation with difficult intubation (p = 0.004). The DSHB had a significant correlation with difficult laryngoscopy (p = 0.002) but its correlation with difficult intubation was not significant (p = 0.629). The DSVC and DSTI had a significant relationship with both difficult laryngoscopy (p = 0.003 and p = 0.001), and difficult intubation (p = 0.025 and p = 0.001). The DBAC had not significant correlation neither with the difficult laryngoscopy (p = 0.142), nor with difficult intubation (p = 0.526).

CONCLUSION

The findings showed that ultrasound parameters including soft tissue DSHB, DSVC and DSTI could be proper predictors of difficult laryngoscopy. Also, HBV, DSVC and DSTI may be proper predictors for difficult intubation. But DBAC was not useful in this regard.

Visual-perceptive assessment of glottic characteristics of vocal nodules by means of high-speed videoendoscopy

OBJECTIVE

Visual-perceptive assessment of glottic characteristics of vocal nodules by means of high-speed videoendoscopy.

METHODS

Descriptive observational research with convenience sampling of five laryngeal videos of women with an average age of 25 years. The diagnosis of vocal nodules was defined by two otolaryngologists, with 100% intra-rater agreement and 53.40% inter-rater agreement and five otolaryngologists as judge assessed the laryngeal videos based on an adapted protocol. The statistical analysis calculated measures of central tendency and dispersion, as well as percentage. The AC1 coefficient was used for agreement analysis.

RESULTS

In high-speed videoendoscopy imaging, vocal nodules are characterized by amplitude of the mucosal wave and muco-undulatory movement with magnitude between 50% and 60%. Non-vibrating segments of vocal folds are scarce, and the glottal cycle does not show a predominant phase, it is symmetric and periodic. Glottal closure is characterized by the presence of a mid-posterior triangular chink (double chink or isolated mid-posterior triangular chink), without movement of supraglottic laryngeal structures, with irregular contour of the free edge of vocal folds, which are vertically on-plane.

CONCLUSION

Vocal nodules present mid-posterior triangular chink and irregular free edge contour. Amplitude and mucosal wave were partially reduced.

LEVEL OF EVIDENCE

Level 4 (Case-series).

Treatment of Early Glottic cancer with Transoral Laser Microsurgery: An Australian Experience

Introduction

Early laryngeal carcinomas may be treated by transoral laser microsurgery (TLM) or external beam radiotherapy. We review our experience of surgical treatment of laryngeal pre-malignant and malignant lesions over the past 15 years in a high-volume head neck unit.

Methods

A review of a prospective patient database of patients with laryngeal SCC, who were treated with CO2 TLM between 2004 and 2019 was carried out.

Results

83 patients with a mean age of 67.7 (SD: 10.6) years underwent primary curative TLM for T1a/b SCC. 5-year overall survival was 93.2% (95%CI 86.9-100%), disease free survival was 86.0% (95%CI 78.1-94.6%), locoregional control was 91.2% (95%CI: 85.1-97.7%) and larynx preservation rate of 95.1% at 5 years.

Conclusion

TLM is an excellent treatment modality for T1 early glottic SCC, with excellent locoregional control and disease-free survival. It is minimally invasive, outpatient-based, and cost-effective procedure preserving upper aerodigestive tract dysfunction for all activities of daily living.

Removal of a fish bone endangering the common carotid artery under general anesthesia with video laryngoscope: A case report

A fish bone penetrating the digestive tract is a common emergency, and its removal often requires endoscopy. We report herein a case in which a fish bone punctured the throat; its front end was close to the common carotid artery, but its back end could not be visualized. Subsequently, we compared the pharyngeal CT and carotid CTA of the patient and found that the fishbone had shifted. So we considered that the end of the fish bone could be rediscovered and successfully removed by a video laryngoscope. Finally, with the patient under deep sedation with maintained spontaneous breathing, the fish bone was removed using video laryngoscopy. This case highlights the importance of rechecking CT scans and the use of laryngoscopy when determining the location of a shifted foreign body at different times and when selecting the removal method.

Pathologically Negative Excision for Biopsy-Proven Early Glottic Carcinoma

In certain instances, patients who underwent endoscopic laser excision (ELE) for biopsy-proven early glottic carcinoma do not show any evidence of carcinomatous cells on histopathologic analysis. Our study aims to determine the incidence of this phenomenon. A retrospective analysis of patients with biopsy-proven early glottic squamous cell carcinoma who underwent ELE was conducted. 121 patients with a mean age of 68.2 ± 10.7 were included in this study. Initial biopsy showed carcinoma in situ in 38 patients, (31.4%), T1a in 41 patients (33.9%), and T1b in 42 patients (34.7%). Following ELE, a pathologically negative excision was seen in 26 patients (21.5%). Disease recurrence occurred in 3 patients who had a pathologically negative excision (11.5%). Following repeat ELE, all patients remained disease free. A significant number of early glottic carcinoma present with small volume disease which may be eradicated with diagnostic biopsy alone.

AGA Clinical Practice Update on the Diagnosis and Management of Extraesophageal Gastroesophageal Reflux Disease: Expert Review

DESCRIPTION

The purpose of this American Gastroenterological Association (AGA) Institute Clinical Practice Update is to review the available evidence and expert advice regarding the clinical management of patients with suspected extraesophageal gastroesophageal reflux disease.

METHODS

This article provides practical advice based on the available published evidence including that identified from recently published reviews from leading investigators in the field, prospective and population studies, clinical trials, and recent clinical guidelines and technical reviews. This best practice document is not based on a formal systematic review. The best practice advice as presented in this document applies to patients with symptoms or conditions suspected to be related to extraesophageal reflux (EER). This expert review was commissioned and approved by the AGA Institute Clinical Practice Updates Committee (CPUC) and the AGA Governing Board to provide timely guidance on a topic of high clinical importance to the AGA membership and underwent internal peer review by the CPUC and external peer review through standard procedures of Clinical Gastroenterology and Hepatology. These Best Practice Advice (BPA) statements were drawn from a review of the published literature and from expert opinion. Because systematic reviews were not performed, these BPA statements do not carry formal ratings of the quality of evidence or strength of the presented considerations. BEST PRACTICE ADVICE 1: Gastroenterologists should be aware of potential extraesophageal manifestations of gastroesophageal reflux disease (GERD) and should inquire about such disorders including laryngitis, chronic cough, asthma, and dental erosions in GERD patients to determine whether GERD may be a contributing factor to these conditions. BEST PRACTICE ADVICE 2: Development of a multidisciplinary approach to extraesophageal (EER) manifestations is an important consideration because the conditions are often multifactorial, requiring input from non-gastroenterology (GI) specialties. Results from diagnostic testing (ie, bronchoscopy, thoracic imaging, laryngoscopy, etc) from non-GI disciplines should be taken into consideration when gastroesophageal reflux (GER) is considered as a cause for extraesophageal symptoms. BEST PRACTICE ADVICE 3: Currently, there is no single diagnostic tool that can conclusively identify GER as the cause of EER symptoms. Determination of the contribution of GER to EER symptoms should be based on the global clinical impression derived from patients' symptoms, response to GER therapy, and results of endoscopy and reflux testing. BEST PRACTICE ADVICE 4: Consideration should be given toward diagnostic testing for reflux before initiation of proton pump inhibitor (PPI) therapy in patients with potential extraesophageal manifestations of GERD, but without typical GERD symptoms. Initial single-dose PPI trial, titrating up to twice daily in those with typical GERD symptoms, is reasonable. BEST PRACTICE ADVICE 5: Symptom improvement of EER manifestations while on PPI therapy may result from mechanisms of action other than acid suppression and should not be regarded as confirmation for GERD. BEST PRACTICE ADVICE 6: In patients with suspected extraesophageal manifestation of GERD who have failed one trial (up to 12 weeks) of PPI therapy, one should consider objective testing for pathologic GER, because additional trials of different PPIs are low yield. BEST PRACTICE ADVICE 7: Initial testing to evaluate for reflux should be tailored to patients' clinical presentation and can include upper endoscopy and ambulatory reflux monitoring studies of acid suppressive therapy. BEST PRACTICE ADVICE 8: Testing can be considered for those with an established objective diagnosis of GERD who do not respond to high doses of acid suppression. Testing can include pH-impedance monitoring while on acid suppression to evaluate the role of ongoing acid or non-acid reflux. BEST PRACTICE ADVICE 9: Alternative treatment methods to acid suppressive therapy (eg, lifestyle modifications, alginate-containing antacids, external upper esophageal sphincter compression device, cognitive-behavioral therapy, neuromodulators) may serve a role in management of EER symptoms. BEST PRACTICE ADVICE 10: Shared decision-making should be performed before referral for anti-reflux surgery for EER when the patient has clear, objectively defined evidence of GERD. However, a lack of response to PPI therapy predicts lack of response to anti-reflux surgery and should be incorporated into the decision process.

Preoperative lignocaine nebulisation for attenuation of the pressor response of laryngoscopy and tracheal intubation in patients with severe preeclampsia undergoing caesarean section delivery: A randomised double-blind controlled trial

Background and Aims

Following induction of general anaesthesia, direct laryngoscopy and endotracheal intubation usually cause tachycardia and hypertension due to increased sympathetic activity. This response is generally exaggerated in hypertensive patients. This study aimed to evaluate the effectiveness of preoperative lignocaine nebulisation in attenuating the pressor response to laryngoscopy and endotracheal intubation in patients with severe preeclampsia undergoing caesarean delivery.

Methods

After ethical approval, we conducted this randomised, double-blind study, which included 110 patients with severe preeclampsia who underwent caesarean delivery under general anaesthesia. These patients were randomly allocated into two groups to receive either preoperative nebulisation of lignocaine 2% in a dose of 4.5 mg/kg (not exceeding 400 mg) in the lignocaine group or nebulisation of an equivalent volume of 0.9% NaCl in the saline group. The primary objective was the systolic blood pressure after tracheal intubation. The secondary objectives included heart rate, maternal serum cortisol and blood glucose levels, grade of cough during emergence, postoperative sore throat and hoarseness of voice, neonatal Apgar score and umbilical blood gas.

Results

The systolic blood pressure was significantly lower in the lignocaine group compared to the saline group at 1, 3 and 5 min after endotracheal intubation and after delivery of the foetus (P = 0.001, 0.003, 0.002 and 0.019, respectively). Similarly, the heart rate was significantly lower in the lignocaine group versus saline group at 1 and 3 min after endotracheal intubation (P = 0.041 and 0.042, respectively).

Conclusion

Preoperative lignocaine nebulisation in a dose of 4.5 mg/kg effectively attenuated the pressor response to laryngoscopy and endotracheal intubation in patients with severe preeclampsia undergoing caesarean delivery.

Recommendations of the AFCE (Association francophone de chirurgie endocrinienne) with the SFE (Société française d'endocrinologie) and the SFMN (Société française de médecine nucléaire)

Preoperative laryngoscopy is mandatory when there is a history of cervical or thoracic surgery, dysphonia, posteriorly developed thyroid carcinoma, or significant lymph node involvement in the central compartment. Postoperative laryngoscopy should be performed for any postoperative dysphonia, swallowing difficulties, respiratory symptoms, or loss of signal during neuromonitoring of the recurrent and/or vagus nerve. Neuromonitoring can be useful in thyroid surgery because it lowers the rate of transient recurrent palsy (RP), although no impact on permanent RP has been demonstrated. It facilitates location of the recurrent nerve. Continuous neuromonitoring of the vagus nerve can, in some situations, allow early detection of a signal drop during dissection near the recurrent nerve.

Securing injection laryngoplasty with anti-reflux valve

BACKGROUND

Injection laryngoplasty (IL) is a common procedure performed by the laryngologist to treat glottal insufficiency. It can be performed under general anaesthesia (GA) or as an office-based procedure. One of the common problems faced during IL is the disconnection between the injection needle and injection material syringe due to high-pressure effect. This may lead to leakage of the injectates especially when injecting high-viscosity materials such as calcium hydroxylapatite (CaHa) or injecting through hard fibrotic scar of the vocal fold.

PURPOSE

Due to this recurring issue, we propose anti-reflux valve as a connector to link up these two devices. The function of anti-reflux valve is to ensure secure connection between these two devices and overcome the problem.

METHODS

The anti-reflux valve that can be used is NeutraClearTM needle-free connector EL-NC1000 or MicroClaveTM clear connector. In our practice, these anti-reflux valves are used together with Integra MicroFrance straight malleable injection needle (0.5 mm diameter, 250 mm length) for IL under GA. However, any other injection needle suitable for IL may also be used with these anti-reflux valves.

RESULTS

Our 3 years' experience has shown good outcome with no reported incidence of device detachment or leakage of injectates during IL procedure.

CONCLUSIONS

Anti-reflux valve is a readily available device in the operating theatre or clinic and only involve simple preparation prior to IL. It is beneficial as an added device in IL procedure.

Conventional versus video-assisted laryngoscopy for perioperative endotracheal intubation (COVALENT) - a randomized, controlled multicenter trial

BACKGROUND

Data on the routine use of video-assisted laryngoscopy in peri-operative intubations are rather inconsistent and ambiguous, in part due to small populations and non-uniform outcome measures in past trials. Failed or prolonged intubation procedures are a reason for relevant morbidity and mortality. This study aims to determine whether video-assisted laryngoscopy (with both Macintosh-shaped and hyperangulated blades) is at least equal to the standard method of direct laryngoscopy with respect to the first-pass success rate. Furthermore, validated tools from the field of human factors will be applied to examine within-team communication and task load during this critical medical procedure.

METHODS

In this randomized, controlled, three-armed parallel group design, multi-centre trial, a total of more than 2500 adult patients scheduled for perioperative endotracheal intubation will be randomized. In equally large arms, video-assisted laryngoscopy with a Macintosh-shaped or a hyperangulated blade will be compared to the standard of care (direct laryngoscopy with Macintosh blade). In a pre-defined hierarchical analysis, we will test the primary outcome for non-inferiority first. If this goal should be met, the design and projected statistical power also allow for subsequent testing for superiority of one of the interventions. Various secondary outcomes will account for patient safety considerations as well as human factors interactions within the provider team and will allow for further exploratory data analysis and hypothesis generation.

DISCUSSION

This randomized controlled trial will provide a solid base of data in a field where reliable evidence is of major clinical importance. With thousands of endotracheal intubations performed every day in operating rooms around the world, every bit of performance improvement translates into increased patient safety and comfort and may eventually prevent significant burden of disease. Therefore, we feel confident that a large trial has the potential to considerably benefit patients and anaesthetists alike.

TRIAL REGISTRATION

ClincalTrials.gov NCT05228288.

PROTOCOL VERSION

1.1, November 15, 2021.

Comparison of Intubation Conditions Between Airtraq, McGrath Video Laryngoscopes, and Macintosh Under Conditions of Simulated Trauma Airway and Rapid Sequence Induction Intubation

BACKGROUND

Patients arriving at the emergency department with a potential cervical spine injury and immobilized in a rigid cervical collar often require emergency airway management and rapid sequence induction intubation (RSII). There have been several advances in airway management with the advent of channeled (Airtraq^Ⓡ; Prodol Meditec) and nonchanneled (McGrath^Ⓡ; Meditronics) video laryngoscopes, which enable intubation without the removal of the cervical collar, but their efficacy and superiority over conventional laryngoscopy (Macintosh) in the presence of a rigid cervical collar and cricoid pressure have not been evaluated.

OBJECTIVE

Our aim was to compare the channeled (Airtraq [group A]) and nonchanneled (McGrath [Group M]) video laryngoscopes with a conventional laryngoscope (Macintosh [Group C]) in a simulated trauma airway.

METHODS

A prospective randomized controlled study was conducted in a tertiary care center. Participants were 300 patients requiring general anesthesia (American Society of Anesthesiologists class I or II), of both sexes, and aged 18-60 years. Airway management was simulated without removal of a rigid cervical collar and using cricoid pressure during intubation. After RSI, patients were intubated with one of the study techniques according to randomization. Intubation time and intubation difficulty scale (IDS) score were noted.

RESULTS

Mean intubation time was 42.2 s in group C, 35.7 s in group M, and 21.8 s in group A (p = 0.001). Intubation was easy in group M and group A (median IDS score of 0; interquartile range [IQR] 0-1 for group M and median IDS score of 1; IQR 0-2 for group A and group C; p < 0.001). A higher proportion (95.1%) of patients had an IDS score of < 1 in group A.

CONCLUSIONS

The performance of RSII with cricoid pressure in the presence of a cervical collar was easier and more rapid with channeled video laryngoscope than with other techniques.

Convolutional neural network based anatomical site identification for laryngoscopy quality control: A multicenter study

OBJECTIVES

Video laryngoscopy is an important diagnostic tool for head and neck cancers. The artificial intelligence (AI) system has been shown to monitor blind spots during esophagogastroduodenoscopy. This study aimed to test the performance of AI-driven intelligent laryngoscopy monitoring assistant (ILMA) for landmark anatomical sites identification on laryngoscopic images and videos based on a convolutional neural network (CNN).

MATERIALS AND METHODS

The laryngoscopic images taken from January to December 2018 were retrospectively collected, and ILMA was developed using the CNN model of Inception-ResNet-v2 + Squeeze-and-Excitation Networks (SENet). A total of 16,000 laryngoscopic images were used for training. These were assigned to 20 landmark anatomical sites covering six major head and neck regions. In addition, the performance of ILMA in identifying anatomical sites was validated using 4000 laryngoscopic images and 25 videos provided by five other tertiary hospitals.

RESULTS

ILMA identified the 20 anatomical sites on the laryngoscopic images with a total accuracy of 97.60 %, and the average sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were 100 %, 99.87 %, 97.65 %, and 99.87 %, respectively. In addition, multicenter clinical verification displayed that the accuracy of ILMA in identifying the 20 targeted anatomical sites in 25 laryngoscopic videos from five hospitals was ≥95 %.

CONCLUSION

The proposed CNN-based ILMA model can rapidly and accurately identify the anatomical sites on laryngoscopic images. The model can reflect the coverage of anatomical regions of the head and neck by laryngoscopy, showing application potential in improving the quality of laryngoscopy.

A prospective validation and comparison of three multivariate models for prediction of difficult intubation in adult patients

PURPOSE

Several bedside clinical tests have been proposed to predict difficult tracheal intubation. Unfortunately, when used alone, these tests show less than ideal prediction performance. Some multivariate tests have been proposed considering that the combination of some criteria could lead to better prediction performance. The goal of our research was to compare three previously described multivariate models in a group of adult patients undergoing general anesthesia.

METHODS

This study included 220 patients scheduled for elective surgery under general anesthesia. A standardized airway evaluation which included modified Mallampati class (MM), thyromental distance (TMD), mouth opening distance (MOD), head and neck movement (HNM), and jaw protrusion capacity was performed before anesthesia. Multivariate models described by El-Ganzouri et al., Naguib et al., and Langeron et al. were calculated using the airway data. After anesthesia induction, an anesthesiologist performed the laryngoscopic classification and tracheal intubation. The sensitivity, specificity, and receiver operating characteristic (ROC) curves of the models were calculated.

RESULTS

The overall incidence of difficult laryngoscopic view (DLV) was 12.7%. The area under curve (AUC) for the Langeron, Naguib, and El-Ganzouri models were 0.834, 0.805, and 0.752, respectively, (Langeron...>...El-Ganzouri, p...=...0.004; Langeron...=...Naguib, p...=...0.278; Naguib...=...El-Ganzouri, p...=...0.101). The sensitivities were 85.7%, 67.9%, and 35.7% for the Langeron, Naguib, and El-Ganzouri models, respectively.

CONCLUSION

The Langeron model had higher overall prediction performance than that of the El-Ganzouri model. Additionally, the Langeron score had higher sensitivity than the Naguib and El-Ganzouri scores, and therefore yielded a lower incidence of false negatives.

Diagnostic work-up of exercise-induced laryngeal obstruction

PURPOSE

Exercise-induced laryngeal obstruction (EILO) is suspected when dyspnea associated with upper airway symptoms is triggered by exercise. This condition affects mainly adolescent athletes. Visualization of the obstruction, while the patient is experiencing the symptoms during continuous laryngoscopy during exercise (CLE-test) is the gold standard for diagnosing EILO. Our study aims to evaluate the prevalence of EILO in a population presenting exercise-induced inspiratory symptoms (EIIS) or uncontrolled asthma with exertional symptoms. The second objective was to evaluate the diagnostic strength of laryngology consultation (LC) and pulmonary function tests (PFTs).

METHODS

All patients referred to our center for EIIS or uncontrolled asthma with exertional symptoms were included. EILO diagnosis was made if Maat score was > 2 for patients with CLE-test or if there were inspiratory anomalies on PFTs and LC. The sensitivity and specificity of LC and PFTs as diagnostic tools were calculated considering CLE-test as the gold standard.

RESULTS

Sixty two patients were referred to our center for EIIS or uncontrolled asthma with exertional symptoms. EILO was diagnosed in 28 patients (56%) with associated asthma in 9 patients (18%). The sensibility and specificity of LC for supraglottic anomalies were 75% and 60%, respectively. The sensibility and specificity of PFTs were 61% and 89%, respectively.

CONCLUSIONS

There was a high prevalence of EILO among patients with EIIS and uncontrolled asthma. Some clinical characteristics might guide the diagnosis. Nevertheless, CLE-test remained the gold standard for EILO diagnosis and identification of the dysfunctional upper airway site to provide specific management.

Transmission risk of COVID-19 infection with office-based flexible laryngoscopy

Since the beginning of the Coronavirus pandemic, recommendations to ensure safety in clinical practice have fluctuated. Within the Otolaryngology community, a variety of protocols have emerged to assure safety for both patients and healthcare workers while maintaining standard of care practices, especially surrounding aerosolizing in-office procedures.

OBJECTIVES

This study aims to describe our Otolaryngology Department's Personal Protective Equipment protocol for both patients and providers during office laryngoscopy and to identify the risk of contracting COVID-19 after implementation of the protocol.

METHODS

18,953 office visits divided between 2019 and 2020 where laryngoscopy was performed were examined and compared to the rate of COVID-19 contraction for both office staff and patients within a 14 day period after the encounter. Of these visits, two cases were examined and discussed; where a patient tested positive for COVID-19 ten days after office laryngoscopy, and one where a patient tested positive for COVID-19 ten days prior to office laryngoscopy.

RESULTS

In the year 2020, 8337 office laryngoscopies were performed, 100 patients tested positive within the year 2020, with only these 2 cases of COVID-19 infections occurring within 14 days prior to or after their office visit.

CONCLUSION

These data suggest that using CDC-compliant protocol for aerosolizing procedures, such as office laryngoscopy, can provide a safe and effective method for mitigating infectious risk while providing timely quality care for the otolaryngology patient.

LEVEL OF EVIDENCE

3 LAY SUMMARY: During the COVID-19 Pandemic, ENTs have had to balance providing care while minimizing the risk of COVID-19 transmission with routine office procedures such as flexible laryngoscopy. In this large chart review, we show that the risk of transmission is low with CDC-compliant protective equipment and cleaning protocols.

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

BACKGROUND

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

OBJECTIVE

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

METHODS

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

RESULTS

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

CONCLUSION

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

Videolaryngoscopy: Channelizing through Intensive Care Unit Intubations

How to cite this article: Kothekar AT, Wajekar AS, Joshi AV. Videolaryngoscopy: Channelizing through Intensive Care Unit Intubations. Indian J Crit Care Med 2023;27(2):85-86.

Evaluating the Quality of Rigid Optic Videolaryngoscopy Image Taken Through Dental Protection Cap and Its Feasibility as Additional Barrier Method Against COVID-19

Videolaryngoscopy screening is essential to help assessing human larynx. The use of 70° optical fiber in association with image recording by analog or digital cameras is one of the methods adopted to perform this examination. Endoscopic exams can contaminate the equipment with several microorganisms. The pandemic caused by the new coronavirus reinforces the importance of developing efficient barrier methods to be adopted in videolaryngoscopy procedures. Although dental intraoral camera covers are a barrier method authorized by Brazilian health organs, it has not yet been used in videolaryngoscopy examinations. The aim of the current longitudinal, individualized, single-blind, prospective, self-controlled, and accurate study is to evaluate the quality of images generated through, and confidence level of, diagnosis based on videolaryngoscopy performed with intraoral dental camera equipped with disposable protection cap and connected to 70° rigid laryngoscope in vocally healthy individuals. Videolaryngoscopy examinations based on 70° rigid optics were performed in 13 euphonic and asymptomatic volunteers at an otorhinolaryngology specialist clinic; only 1 patient was excluded from the study. Images were taken with, and without, disposable intraoral dental camera protection cap; high-grade disinfection protocol was applied between examinations. Recorded videos were randomly distributed in a single-blind manner in order to be evaluated by four otorhinolaryngologists, who answered a questionnaire comprising three questions. Statistical analysis was used to compare groups - which were defined by the use, or not, of protection cap - based on Wilcoxon nonparametric test. Statistical significance was set at 5% with 95% confidence interval. There was no statistically significant difference in image quality between examinations performed with, and without, protection cap (P= 0.646) or in the diagnosis confidence level of examinations performed with, or without, the barrier method. The use of disposable protection cap on intraoral dental camera did not significantly change the quality of images taken through videolaryngoscopy performed with 70° rigid optics in vocally healthy patients.

The Evolution of Equipment and Technology for Visualising the Larynx and Airway

Laryngoscopy and endotracheal intubation are the core skills of an anaesthetist. The tools and equipment used today are unrecognisable from the methods used in the first recorded attempts at laryngoscopy over 200 years ago. The evolution of the modern-day laryngoscopes has mirrored advancements in technology within general society, and particularly with regard to computer and fibreoptic technology over the last 30 years. The development of these modern visualisation devices would not have been possible without those that went before it, as each new device has been influenced by the previous. Video laryngoscopes have quickly gained popularity as the primary intubating device in many scenarios, driven by ease of use as well as positive patient outcomes. While it is still debated whether videolaryngoscopes can replace direct laryngoscopy for routine intubations, their effectiveness in difficult airways is unquestioned. This chapter will cover the anatomy of the airway and the development of technology from the rudimentary creations in the early 1700s to the modern larynsgocopes created in the twenty-second century which allow the user to view the airway in more detail in order to secure endotracheal intubation even in an airway where intubation would be difficult.

Ultrasound Evaluation to Predict Difficult Laryngoscopy in Children below 2 Years

OBJECTIVE

To evaluate the feasibility of sonography as a tool to predict difficult airway in children less than 2 y of age.

METHODS

Airway ultrasound was performed in 90 children below the age of 2 y to measure airway dimensions preoperatively. Hyomental distance ratio in predicting difficult laryngoscopy was recorded as the primary outcome. Secondary outcomes included tongue thickness/oral cavity thickness ratio and tongue thickness/thyromental distance ratio in predicting difficult laryngoscopy and difficult intubation, time taken for intubation, and any complications. The sensitivity, specificity, positive predictive value, and negative predictive value with 95% CI of all the parameters were recorded.

RESULTS

Six out of 90 (6.7%) patients had difficult laryngoscopy. HMDR was significantly different between children with easy and difficult laryngoscopy (1.15 ± 0.11 vs. 1.03 ± 0.016, p = 0.001). The optimal cutoff points for HMDR, TT/OCT, and TT/TMD to predict difficult laryngoscopy (CL grade III, IV) were > 1.055 (sensitivity 100%, specificity 86.9%), 0.755 (sensitivity 100%, specificity 57%), and 0.445 (sensitivity 53.5%, specificity 66.7%), respectively, the AUC being highest for HMDR (0.959). The cutoff value of ≥ 1.055 of HMDR to predict difficult laryngoscopy had the highest AUC of 0.959, p < 0.001. Fifty-two children had IDS = 0, while 38 had IDS between 1 and 4. None of the patients had IDS > 5.

CONCLUSIONS

Ultrasound-guided airway assessment is a feasible option in children less than 2 y. Hyomental distance ratio can form a useful tool for predicting difficult airway in this age group.

TRIAL REGISTRATION

The trial has been registered in Clinical trial Registry of India (CTRI/2019/05/019014) before enrollment of the first patient.

A prospective randomized study of different height of operation table for tracheal intubation with videolaryngoscopy in ramped position

BACKGROUND

Previous studies have reported that the ramped position provides a better laryngoscopic view, reduces tracheal intubation time, and increases the success rate of endotracheal intubation. However, the patient's head height changes while in the ramped position, which in turn changes the relative positions of the patient and intubator. Thus, making these changes may affect the efficiency of tracheal intubation; however, few studies have addressed this problem. This study analyzed intubation time and conditions during tracheal intubation using videolaryngoscope in the ramped position.

METHODS

This prospective study included 144 patients who were scheduled to receive general anesthesia for surgeries involving orotracheal intubation. The participants were randomly allocated to either the nipple or umbilical group according to the table height. Mask ventilation was assessed using the Warters grading scale. Tracheal intubation was performed using a McGrath MAC laryngoscope. The total intubation time, laryngoscopy time, tube insertion time, and difficulty of intubation (IDS score) were measured.

RESULTS

The umbilical group had a significantly shorter laryngoscopy time (10 ± 3 vs. 16 ± 4 s), tube insertion time (18 ± 4 vs. 24 ± 6 s), and total intubation time (28 ± 5 vs. 40 ± 7 s) compared to the nipple group. No significant difference in the difficulty of mask ventilation was observed between the two groups. The IDS score was higher in the nipple than umbilical group.

CONCLUSION

The lower (umbilical) table level reduced the intubation time and difficulty of videolaryngoscopy compared to the higher (nipple) table level.

TRIAL REGISTRATION

This study was registered at KCT0005987, 11/03/2021, Retrospectively registered.