Preoperative Acetaminophen For Microsuspension Laryngoscopy Reduces Postoperative Opioid Use.

OBJECTIVES: The opioid crisis has prompted consideration of analgesic prescriptions. This study explored the value of preoperative acetaminophen for pain control following microsuspension laryngoscopy (MSL) and compared the results with a previous study of pain and opioid use following MSL (Tsang et al.). METHODS: A prospective open-label clinical trial was conducted in patients undergoing MSL. All patients were administered preoperative acetaminophen. Short-form McGill Pain Questionnaire (SF-MPQ), pain visual analogue scale (VAS), and present pain intensity (PPI) scores were collected preoperatively and on postoperative days (PODs) 1, 3, 7, and 14. Statistical analysis identified variables associated with opioid use or increased pain scores, and compared outcomes with Tsang et al. RESULTS: Eighty-nine patients were included (mean age 52.8 ± 17.3 years, 40 males). All patients received preoperative 1 g acetaminophen (77 (86.5%) orally) with no adverse effects. On POD1, opioid usage was 10%. Median [IQR] pain scores were 5 [2-11], 21 [12.3-56.8], and 3 [2-3.3] on SF-MPQ, VAS, and PPI, respectively. Post-Anesthesia Care Unit (PACU) opioid requirements significantly correlated with POD1 opioid consumption (τb = 0.214; p ≤ 0.05), and significant associations with PACU opioid administration were found for total anesthesia time (OR (95%CI) = 1.271 (1.043-1.548), p = 0.017) and total laryngoscope suspension time (OR (95%CI) = 0.791 (0.651-0.962, p = 0.019)). This cohort demonstrated reduced opioid usage on POD1 compared with Tsang et al (23%). CONCLUSIONS: Preoperative acetaminophen is a safe intervention, resulting in decreased postoperative opioid use following MSL. Anesthesia time correlated with need for postoperative opioids. LEVEL OF EVIDENCE: 4 Laryngoscope, 134:4625-4635, 2024.

Ultrasound-based airway assessment in obese patients as a valuable tool for predicting difficult airway: an observational study.

BACKGROUND: Difficult airway, characterized by difficult mask ventilation and intubation, is common in obese patients undergoing surgery. The purpose of this study was to evaluate and compare the prognostic efficiency of ultrasound-measured anterior cervical soft tissue parameters as an indicator of difficult airway during anesthesia induction in obese patients. METHODS: This prospective, double-blind, observational study was conducted at Balikesir University Faculty of Medicine Hospital between March 2020 and March 2022. A total of 157 patients age ≥ 18 (BMI ≥ 30 kg.m-2), without previous head and neck surgery were included in the study. Anterior cervical soft tissue measurements were performed at three levels; minimum distance between the hyoid bone and skin at the level of the hyoid bone; (DSHB), distance between the midpoint of the epiglottis and skin at the level of the thyrohyoid membrane; (DSE), distance between the anterior commissure of vocal cords and skin at the vocal cord level; (DSV). The Han scale was used to assess difficult mask ventilation and the Cormack-Lehane scale was used to assess difficult laryngoscopy. RESULTS: In the difficult laryngoscopy group, the mean values of DSHB, DSE and DSV were 18.5 ± 3.5, 18.3 ± 3.8, and 18.6 ± 3.4, respectively. The AUC values for DSHB, DSE, and DSV were 0.845, 0.827, and 0.850, respectively. Anterior cervical measurements showed a better predictive value for difficult laryngoscopy compared to difficult mask ventilation. CONCLUSION: Ultrasonographic measurements were predictive for difficult laryngoscopy and ventilation with better correlation in laryngoscopy.

In-office Laryngeal Procedures: a Modern Perspective for Vocal Fold Interventions

Introduction: The purpose of this article is to discuss in-office laryngeal procedures as an alternative to surgical intervention under general anesthesia. In-office procedures have become more common due to technological advancements. As a result, these approaches are less invasive and more patient-friendly, with increased pain tolerance and reduced procedure time and cost. Methods: We conducted a thematic analysis of published reports regarding the best known and performed in-office laryngeal interventions. Three questions guided our analysis: What laryngological procedures can be performed in the office setting? What are the advantages of in-office laryngology procedures compared to operating room surgical procedures? Why aren't more in-office procedures performed in some Latin American countries? Discussion: Despite being performed more frequently, there is still controversy whether in-office procedures should be performed as often due to the risk of complications. Furthermore, procedures that are done in the office setting are more popular in some countries than in others, even though their benefit has been well demonstrated. This article describes various in-office procedures, including biopsy, vocal fold injections, and laser surgery. We also discuss what factors might contribute to having office-procedures being performed more frequently in some countries than others. Conclusion: Awake interventions offer numerous benefits, including shorter procedure time, reduced costs, and lower patient morbidity. These advantages have significantly transformed the treatment of laryngeal diseases in modern laryngology practice in a global manner.

Introducción: El propósito de este artículo es discutir los procedimientos laríngeos en el consultorio como una alternativa a la intervención quirúrgica bajo anestesia general. Los procedimientos en consultorio se han vuelto más comunes debido a los avances tecnológicos. Como resultado, estos enfoques son menos invasivos y más amigables para el paciente, con mayor tolerancia al dolor y reducción del tiempo y costo del procedimiento. Métodos: Realizamos un análisis temático de los informes publicados sobre las intervenciones laríngeas más conocidas y realizadas. Tres preguntas guiaron nuestro análisis: ¿Qué procedimientos laringológicos se pueden realizar en el consultorio y cuales sin los más frecuentes?, ¿cuáles son las ventajas de los procedimientos laringológicos fuera del quirófano frente a los que se realizan bajo anestesia general?, ¿por qué no se realizan más procedimientos laringológicos en el consultorio en la mayoría de los países en Latinoamérica? Discusión: A pesar de que se realizan con mayor frecuencia, aún existe controversia sobre si los procedimientos en consultorio deben realizarse con tanta frecuencia debido al riesgo de complicaciones. Además, los procedimientos que se realizan en el consultorio son más populares en algunos países que en otros, aunque sus beneficios han sido bien demostrados. Este artículo describe varios procedimientos en el consultorio, incluida la biopsia, las inyecciones de cuerdas vocales y la cirugía con láser. También se discutieron los factores que podrían contribuir a que los procedimientos en el consultorio se realicen con más frecuencia en algunos países que en otros. Conclusión: Las intervenciones con pacientes despiertos ofrecen numerosos beneficios, incluido un tiempo de procedimiento más corto, costos reducidos y una menor morbilidad para el paciente. Estas ventajas han transformado significativamente el tratamiento de las enfermedades laríngeas en la práctica de la laringología moderna a nivel mundial.

Should videolaryngoscopy be routinely used for airway management? An approach from different scenarios in medical practice

During the past two decades, the videolaryngoscope (VDL) has become a valuable and effective tool for the management of the airway, not just in the realm of anesthesiology, but also in other medical specialties in clinical scenarios requiring tracheal intubation. In countries such as the United States, this represents over 15 million cases in the operating room and 650,000 outside the OR. The overall accumulated incidence of difficult airway is 6.8% events in routine practice and between 0.1 and 0.3 % of failed intubations, both associated with complications such as desaturation, airway injury, hemodynamic instability and death. Notwithstanding the fact that the VDL has proven advantages such as improved visualization of the glottis, higher first attempt success rates, and a shortened learning curve, most of the time its use is limited to rescue attempts or as a secondary option. The aim of this article is to comment the advantages and limitations of the VDL vs. the direct laryngoscope in a wide range of clinical settings, including the operating room, intensive care units, emergency departments, pediatrics, obstetrics, and Covid-19 to consider its routine use.

En las últimas dos décadas, el videolaringoscopio (VDL) se ha convertido en una herramienta valiosa y eficaz para el manejo de la vía aérea no solo en el ámbito de anestesiología, sino en otras especialidades médicas durante escenarios clínicos que requieren la intubación traqueal y las cuales, en países como Estados Unidos corresponden anualmente a más de 15 millones dentro de salas de cirugía y 650.000 fuera de ella. Aproximadamente, hay una incidencia global acumulada de 6,8 % de eventos de vía aérea difícil en la práctica rutinaria y 0,1 al 0,3 % de intubaciones fallidas, ambas asociadas a complicaciones como desaturación, daño en la vía aérea, inestabilidad hemodinámica y muerte. Pese a que el VDL ha demostrado ventajas como mejoría de la visualización de la glotis, aumento de tasa de éxito al primer intento y menor curva de aprendizaje, su uso en la mayoría de las veces se ve limitado como dispositivo de rescate o de manera secundaria. El propósito de este artículo es comentar acerca de las ventajas y limitaciones del VDL vs. el laringoscopio directo en un variado número de escenarios clínicos, como salas de cirugía, unidades de cuidado intensivo, emergenciología, pediatría, obstetricia y covid-19, con el fin de considerar si su uso debiera hacerse de manera rutinaria.

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.

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.

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 pediatric care

Abstract 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

Abstract 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.

Fetal Laryngoscopy and Endoscopic Tracheal Intubation to Avoid ex utero Intrapartum Treatment in the Management of Fetuses with Suspected Airway Obstruction.

INTRODUCTION: Large congenital neck tumors can cause neonatal death due to airway obstruction. The aim of this study was to report outcomes of the first cohort of fetuses with neck masses and suspected airway obstruction managed with fetal laryngoscopy (FL) and fetal endoscopic tracheal intubation (FETI) to secure fetal airways and avoid ex utero intrapartum treatment (EXIT) procedure. METHODS: A prospective observational cohort of consecutive fetuses with neck masses that were candidates for an EXIT procedure due to suspicion of laryngeal and/or tracheal occlusion on ultrasonographic (US) or magnetic resonance imaging (MRI) examination were recruited for FL in a tertiary referral center in Queretaro, Mexico. FETI was performed if the obstruction was confirmed by FL. Maternal and perinatal outcomes were evaluated. RESULTS: Between January 2012 and March 2023, 35 cases with neck masses were evaluated. Airway obstruction was suspected in 12/35 (34.3%), either by US in 10/35 (28.6%) or by fetal MRI in 2/35 (5.7%). In all cases, FL was successfully performed at the first attempt at a median gestational age (GA) of 36+5 (range, 33+5-39+6) weeks+days, with a median surgical time of 22.5 (12-35) min. In 4 cases, airway patency was confirmed during FL and an EXIT procedure was avoided. In 8/12 cases (66.7%), airway obstruction was confirmed during fetoscopy and FETI was successfully performed at a median GA of 36+3 (33+2-38+5) weeks+days, with a median surgical time of 25.0 (range, 12-45) min. No case required an EXIT procedure. All patients underwent conventional cesarean delivery with no maternal complications and all neonates were admitted to the neonatal intensive care unit with a correctly positioned endotracheal tube (ETT) immediately after delivery. Three neonatal deaths (37.5%) were reported due to postnatal unplanned extubation, failed ETT replacement, and tumoral bleeding. CONCLUSION: In fetuses with neck masses and suspected airway obstruction, FL and FETI are feasible and could replace EXIT procedures with good maternal and perinatal outcomes.

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).

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

Abstract 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.

The clinical assessment of foreign body ingestions: Experience in a developing country.

Foreign body (FB) ingestion is an important emergency in low- to middle-income countries. Our study sought to identify which clinical and radiological findings best predict upper gastrointestinal FB impaction. Amongst 149 adolescents and adults presenting to two Jamaican hospitals between 2018 and 2020, FB's were found at 31% of telescopic laryngoscopies and 60% of rigid oesophagoscopies. Commonest sites of impaction were the tonsils at laryngoscopy (15/46) and proximal oesophagus at oesophagoscopy (17/22). Odds of pharyngeal impaction were higher with fish bone ingestion, persistent discomfort, perceived location of discomfort above the cricoid cartilage and symptoms noted during a meal. Persistent discomfort and FB shadow on X-ray imaging produced higher odds of oesophageal impaction. Simple clinical and radiological assessments are useful in predicting FB impaction in resource-limited settings.

Transoral flexible laser surgery of the upper aerodigestive tract with blue laser.

PURPOSE: The introduction of fiber-guided lasers was a breakthrough in laryngology practice, opening the path for treating different pathologies with minimally invasive procedures, both in the operating room and in the office. The most recent technology in the area is the blue laser, which combines photoangiolytic and cutting properties, characteristics that make this equipment suitable for its use in upper aerodigestive tract surgery. However, there is not enough experience in this area. The authors present a case series of patients with different pharyngeal, laryngeal, and tracheal pathologies who were treated by means of transoral procedures using fiber-guided blue laser. METHODS: The surgical records of patients with different upper aerodigestive tract pathologies who were treated with fiber-guided blue laser in the operating room, under general anesthesia with jet ventilation or supraglottic ventilation using suspension laryngotracheoscopy techniques between February 2018 and March 2022 were reviewed. RESULTS: A total of 80 surgical interventions in a group of 38 patients were performed. A wide variety of procedures was executed, either using the laser alone or in combination with other techniques to treat different pathologies of the aero-digestive tract safely and effectively, with adequate functional results. CONCLUSIONS: Following all necessary precautions, blue laser is a reliable tool to perform minimally invasive surgeries in the operating room using TOFLS techniques. It can be used alone or in combination with other devices to achieve the desired goals.

Predictive performance of thyromental height for difficult laryngoscopies in adults: a systematic review and meta-analysis.

BACKGROUND: Thyromental height (TMH) was first reported as a great single test for prediction of difficult laryngoscopies, although further studies have shown variable estimates of its accuracy. We thus performed this meta-analysis to summarize the predictive values of TMH mainly for prediction of difficult laryngoscopies. METHODS: A search in PubMed, EMBASE, LILACS, and Scielo was conducted in June 2020. We included prospective cohorts fully reported with patients ... 16 years old, providing data on predictive values of TMH for prediction of either difficult laryngoscopies or difficult intubations. Diagnostic properties and association between TMH and Cormack and Lehanes...s classification by direct laryngoscopy were evaluated. A random-effects meta-analysis using hierarchical models was performed. RESULTS: Eight studies evaluating 2844 patients were included. All included studies had high risk of bias and low concern regarding applicability. There was significant heterogeneity among the studies. The pooled diagnostic odds ratio (DOR) and positive (LR+) and negative (LR-) likelihood ratios were as follows: DOR, 57.94 (95% CI: 18.19...184.55); LR+, 11.32 (95% CI: 4.28...29.92); and LR-, 0.23 (95% CI: 0.15...0.35). Summary sensitivity and specificity for studies with common threshold were 82.6 (95% CI: 74...88.8%) and 93.5 (95% CI: 79...98.2%), respectively. The estimated AUC was 81.1%. CONCLUSION: TMH arises as a good predictor of difficult laryngoscopies in adult patients from diverse populations presenting better predictive values than most previously reported bedside tests. However, the high risk of bias throughout the studies may have skewed the results of the individual research as well as the summary points of the present meta-analysis.

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.

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.

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.

Role of melatonin in attenuation of hemodynamic response to intubation and anesthetic requirements: a randomized, controlled, double-blind study.

BACKGROUND: Melatonin has been studied to have anxiolytic, sedative, and analgesic effects. However, there is limited data on the effect of melatonin in the attenuation of hemodynamic response to intubation. We aimed to study whether preanesthetic oral melatonin attenuates hemodynamic responses to intubation and anesthetic requirements. METHODS: Sixty-four patients scheduled for laparoscopic cholecystectomy were randomized into melatonin or placebo group (n...=...32 each). Melatonin group received two tablets (3...mg each) of melatonin, and the placebo group received two tablets of vitamin D3 120...min before induction. Hemodynamic parameters were recorded during induction and postintubation for 15...minutes. Total induction dose of propofol, total intraoperative fentanyl consumption, and adverse effects of melatonin were also noted. RESULTS: Postintubation rise in heart rate (HR) was less in the melatonin group compared to the placebo group (10.59% vs. 37.08% at 1...min, respectively) (p...<...0.0001). Maximum percentage increase in systolic blood pressure (SBP), diastolic blood pressure (DBP), and mean blood pressure (MBP) was lesser in melatonin group than placebo group (SBP 9.25% vs. 37.73%, DBP 10.58% vs. 35.51%, MBP 9.99% vs. 36.45% at 1 min postintubation. respectively) (p...<...0.0001). Induction dose of propofol (1.42 mg.kg-1 vs. 2.01...mg.kg-1) and the number of patients requiring additional fentanyl intraoperatively (3 vs. 11) were also significantly reduced in the melatonin group. CONCLUSION: Premedication with 6...mg of oral melatonin resulted in significant attenuation of postintubation rise in HR, SBP, DBP, and MBP. It also reduced the induction dose of propofol, total intraoperative fentanyl consumption without any adverse effects.