UNASSIGNED: Studies have shown that there are differences in clinical evaluation parameters and difficult intubation rates among different ethnic populations. In our study, we aimed to evaluate the efficacy of upper airway clinical and ultrasonographic measurement methods in Turkish population.
UNASSIGNED: Our study is a single-center, prospective, observational study conducted with 402 patients. All patients underwent clinical airway measurements which are routinely used in pre-anesthetic evaluation. In addition, ultrasonographic anterior neck soft tissue thickness measurements of each patient were made and recorded.
UNASSIGNED: Among the clinical measurements, we found the neck circumference/thyromental distance (TMD) ratio to be significant with a cut-off value of 5.5 and a sensitivity of 92.9% and a specificity of 88.3%, while among the ultrasonographic anterior neck measurements, we found the skin-epiglottic distance to be the most sensitive measurement. We found that there was a positive relationship between the neck circumference/TMD ratio and skin-epiglottis.
UNASSIGNED: In our study, we found that routine measurement methods used in airway examination alone are not sufficient, and measurements that take into account the body proportions of the patients, such as the neck circumference/TMD ratio and the ultrasonographic evaluations are more useful in predicting difficult intubation.

The GlideScope® is a videolaryngoscope manufactured by Verathon Medical (Bothell, WA, USA), now widely used to manage planned or unexpected difficult orotracheal intubation situations. According to the current literature, GlideScope® has been used for surgical procedures involving the tongue base, such as biopsies and radiofrequency treatment of obstructive sleep apnea. We describe a case of dual use of GlideScope for pointed foreign body removal in an emergency department.

Retrograde intubation is an historic technique that is now rarely used in difficult airway situations. Although not originally designed for this purpose, the use of an S-guide is a feasible option to aid retrograde intubation because of its malleable rigid body and atraumatic tip.

Background/Objectives: Prediction of a difficult airway during pre-anesthetic evaluation is of great importance because it enables an adequate anesthetic approach and airway management. As there is a scarcity of prospective studies evaluating the role of anthropometric measures of the face and neck in predicting difficult airways in infants with an apparently normal airway, we aimed to identify the aforementioned predictors of difficult facemask ventilation and intubation in infants. Methods: A prospective, observational study that included 97 infants requiring general endotracheal anesthesia was conducted. Anthropometric and specific facial measurements were obtained before ventilation and intubation. Results: The incidence of difficult facemask ventilation was 15.5% and 38.1% for difficult intubation. SMD (sternomental distance), TMA (tragus-to-mouth angle distance), NL (neck length) and mouth opening were significantly lower in the difficult facemask ventilation group. HMDn (hyomental distance in neutral head position), HMDe (hyomental distance in neck extension), TMD (thyromental distance), SMD, mandibular development and mouth opening were significantly different in the intubation difficulty group compared to the non-difficult group. HMDn and HMDe showed significantly greater specificities for difficult intubation (83.8% and 76.7%, respectively), while higher sensitivities were observed in TMD, SMD and RHSMD (ratio of height to SMD) (89.2%, 75.7%, and 70.3%, respectively). Regarding difficult facemask ventilation, TMA showed greater sensitivity (86.7%) and SMD showed greater specificity (80%) compared to other anthropometric parameters. In a multivariate model, BMI (body mass index), COPUR (Colorado Pediatric Airway Score), BOV (best oropharyngeal view) and TMA were found to be independent predictors of difficult intubation, while BMI, ASA (The American Society Physical Status Classification System), CL (Cormack-Lehane Score), TMA and SMD predicted difficult facemask ventilation. Conclusions: Preoperative airway assessment is of great importance for ventilation and intubation. Patient\'s overall condition and facial measurements can be used as predictors of difficult intubation and ventilation.

BACKGROUND: This systematic review aims to assist clinical decision-making in selecting appropriate preoperative prediction methods for difficult tracheal intubation by identifying and synthesizing literature on these methods in adult patients undergoing all types of surgery.
METHODS: A systematic review and meta-analysis were conducted following PRISMA guidelines. Comprehensive electronic searches across multiple databases were completed on March 28, 2023. Two researchers independently screened, selected studies, and extracted data. A total of 227 articles representing 526 studies were included and evaluated for bias using the QUADAS-2 tool. Meta-Disc software computed pooled sensitivity (SEN), specificity (SPC), positive likelihood ratio (PLR), negative likelihood ratio (NLR), and diagnostic odds ratio (DOR). Heterogeneity was assessed using the Spearman correlation coefficient, Cochran\'s-Q, and I2 index, with meta-regression exploring sources of heterogeneity. Publication bias was evaluated using Deeks\' funnel plot.
RESULTS: Out of 2906 articles retrieved, 227 met the inclusion criteria, encompassing a total of 686,089 patients. The review examined 11 methods for predicting difficult tracheal intubation, categorized into physical examination, multivariate scoring system, and imaging test. The modified Mallampati test (MMT) showed a SEN of 0.39 and SPC of 0.86, while the thyromental distance (TMD) had a SEN of 0.38 and SPC of 0.83. The upper lip bite test (ULBT) presented a SEN of 0.52 and SPC of 0.84. Multivariate scoring systems like LEMON and Wilson\'s risk score demonstrated moderate sensitivity and specificity. Imaging tests, particularly ultrasound-based methods such as the distance from the skin to the epiglottis (US-DSE), exhibited higher sensitivity (0.80) and specificity (0.77). Significant heterogeneity was identified across studies, influenced by factors such as sample size and study design.
CONCLUSIONS: No single preoperative prediction method shows clear superiority for predicting difficult tracheal intubation. The evidence supports a combined approach using multiple methods tailored to specific patient demographics and clinical contexts. Future research should focus on integrating advanced technologies like artificial intelligence and deep learning to improve predictive models. Standardizing testing procedures and establishing clear cut-off values are essential for enhancing prediction reliability and accuracy. Implementing a multi-modal predictive approach may reduce unanticipated difficult intubations, improving patient safety and outcomes.

Supraglottic masses can be an anaesthesiologist\'s nightmare due to the difficult airway scenario and bleeding risk during airway manipulation. Awake fibreoptic intubation is the primary method to secure the airway in such cases. However, most practising anaesthesiologists are not experts at handling the fibreoptic scope, especially in cases with a floppy supraglottic mass where it becomes difficult to displace the mask with the thin flexible bronchoscope. A hybrid technique of intubation in supraglottic masses using Bonfils rigid scope and C-MAC is often described but frequently not available. Here we describe a case of an elderly patient in their 80s presenting with a floppy supraglottic mass where an awake fibreoptic bronchoscope failed to secure the airway. Without access to a rigid Bonfils scope, we intuitively used a C-MAC to visualize the larynx and a yankauer suction catheter to displace the mass and perform a bougie-guided endotracheal intubation.

UNASSIGNED: Predicting difficult airway and preparedness for the same can help prevent catastrophic situations while handling the airway. With the increasing familiarity of anaesthesiologists to the use of ultrasound machine and its easy availability and non-invasiveness, we sought to study its utility in airway assessment, by measuring the thickness of tongue, to predict difficult laryngoscopy and intubation.
UNASSIGNED: A total of 85 patients undergoing elective surgeries under general anaesthesia with endotracheal intubation were examined preoperatively. Tongue thickness was measured using submental ultrasonography in the median sagittal plane along with other tests of airway assessment. Cormack Lehane grade on laryngoscopy and Intubation Difficulty Scale Score was recorded. The sensitivity, specificity, positive and negative predictive value, and accuracy was calculated for tongue thickness for predicting difficult intubation.
UNASSIGNED: The tongue thickness in those with difficult intubation (4.83 ± 0.62) was significantly higher than those without difficult intubation (4.38 ± 0.65). The ratio of tongue thickness to thyromental distance was also significantly higher in difficult intubation group. The area under the receiver operating characteristic curve for predicting difficult laryngoscopy and intubation was higher for tongue thickness as compared to other clinical parameters. The sensitivity and specificity of tongue thickness to predict difficult laryngoscopy was 100% and 83%, respectively, and to predict difficult intubation was 72% and 59%, respectively, with an accuracy of 72%.
UNASSIGNED: Ultrasound based assessment of tongue thickness can be a useful predictor of difficult airway along with clinical assessment of the airway.

Subglottic stenosis (SGS) can be asymptomatic in cases with slow-growing granulomas. In this study, we report a case of SGS discovered during tracheal intubation for anesthesia induction. A 74-year-old woman was scheduled for surgery under general anesthesia for a left humeral fracture. Resistance was observed when the tracheal tube passed through the glottis, stopping the tube from advancing. We placed a laryngeal mask (LMA) to secure her airway and examined it using a bronchial fiber to detect circumferential stenosis of the subglottis due to granulation. The airway was secured using an LMA instead of intubation, and the patient was successfully managed under anesthesia. Asymptomatic SGS is difficult to detect preoperatively, and anesthesiologists may encounter unexpected intubation issues. LMA is an important tool for an effective strategy to manage intubation difficulties.

In general anesthesia for Klippel-Feil syndrome (KFS) patients, there is a potential risk of difficult intubation. However, airway assessment to predict difficult intubation for KFS patients is not known. In Patient 1, cervical spine computed tomography (CT) revealed airway compression due to cervical fusion. For airway assessment, bronchofiberscopy, three-dimensional (3-D) CT, and virtual bronchoscopic image (VBI) construction were performed. Based on these images, fiberoptic nasotracheal awake intubation was performed. In Patient 2, magnetic resonance imaging and bronchofiberscopy showed no airway compression due to cervical fusion; therefore, tracheal intubation was performed using a video laryngoscope after anesthetic administration. Airway compression due to cervical fusion is considered one of the risk factors for difficult intubation in KFS patients.

UNASSIGNED: Airway management of patients with long-standing diabetes poses a major challenge for anaesthesiologists due to stiff joint syndrome affecting the atlanto-occipital joint. In certain cases requiring immobilization, the Mallampati test must often be performed in the supine position for obvious reasons.
UNASSIGNED: Hence, we determined the diagnostic precision (sensitivity and specificity) of the modified Mallampati test in sitting and supine positions among the diabetic population in predicting difficult tracheal intubation.
UNASSIGNED: A single-center prospective observational study on adult diabetic patients undergoing general anesthesia and orotracheal intubation was carried out. An observer recorded the modified Mallampati in the sitting posture during the pre-anesthetic examination. The Mallampati in the supine position was determined while in the operating room, and the difficulty of intubation was noted, and diagnostic precision was calculated. The main objective was to predict a difficult airway by calculating the sensitivity, specificity, positive predictive value, and negative predictive value.
UNASSIGNED: Out of the 150 participants, Mallampati grading in a sitting position was correctly able to identify 42.5% of difficult intubation cases, whereas it was 97.5% with Mallampati in the supine position. Mallampati grading in the sitting position was able to correctly identify 89.1% of easy intubation cases, which was 63.6% with Mallampati in the supine position. The correlation of Mallampati in the supine position with CL grading was statistically significant (P < 0.001).
UNASSIGNED: Among diabetic patients, the modified Mallampati test in the supine position can be considered a more accurate and sensitive predictor of difficult intubation than the sitting posture.