Executive Summary of the Spanish Society of Anesthesiology, Reanimation and Pain Therapy (SEDAR) Spanish Society of Emergency and Emergency Medicine (SEMES) and Spanish Society of Otolaryngology, Head and Neck Surgery (SEORL-CCC) Guideline for difficult airway management.

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

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.

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

Abstract 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 randomized prospective controlled trial comparing the laryngeal tube suction disposable and the supreme laryngeal mask airway: the influence of head and neck position on oropharyngeal seal pressure.

BACKGROUND: The Laryngeal Tube Suction Disposable (LTS-D) and the Supreme Laryngeal Mask Airway (SLMA) are second generation supraglottic airway devices (SADs) with an added channel to allow gastric drainage. We studied the efficacy of these devices when using pressure controlled mechanical ventilation during general anesthesia for short and medium duration surgical procedures and compared the oropharyngeal seal pressure in different head and-neck positions. METHODS: Eighty patients in each group had either LTS-D or SLMA for airway management. The patients were recruited in two different institutions. Primary outcome variables were the oropharyngeal seal pressures in neutral, flexion, extension, right and left head-neck position. Secondary outcome variables were time to achieve an effective airway, ease of insertion, number of attempts, maneuvers necessary during insertion, ventilatory parameters, success of gastric tube insertion and incidence of complications. RESULTS: The oropharyngeal seal pressure achieved with the LTS-D was higher than the SLMA in, (extension (p=0.0150) and right position (p=0.0268 at 60 cm H2O intracuff pressures and nearly significant in neutral position (p = 0.0571). The oropharyngeal seal pressure was significantly higher with the LTS-D during neck extension as compared to SLMA (p= 0.015). Similar oropharyngeal seal pressures were detected in all other positions with each device. The secondary outcomes were comparable between both groups. Patients ventilated with LTS-D had higher incidence of sore throat (p = 0.527). No major complications occurred. CONCLUSIONS: Better oropharyngeal seal pressure was achieved with the LTS-D in head-neck right and extension positions , although it did not appear to have significance in alteration of management using pressure control mechanical ventilation in neutral position. The fiberoptic view was better with the SLMA. The post-operative sore throat incidence was higher in the LTS-D. TRIAL REGISTRATION: ClinicalTrials.gov ID: NCT02856672 , Unique Protocol ID:BnaiZionMC-16-LG-001, Registered: August 2016.

Inducción inhalatoria y anestesia tópica de la vía aérea guiada por videolaringoscopio C-MAC pala d-Blade en un paciente con miastenia gravis y vía aérea difícil / Inhaled induction and topical anesthesia of the airway guided with C-MAC d-Blade videolangyscope in a myasthenia gravis patient and difñcult airway

Se describe el caso de un paciente, diagnosticado de miastenia gravis, con factores predicto-res de intubación y ventilación difícil, al que se practica cirugía de eventroplastia y resección intestinal de urgencia, que fue intubado dormido, sin relajación neuromuscular, de forma exitosa con un videolaringoscopio C-MAC y pala específica para intubación difícil (d-Blade), tras inducción inhalatoria y anestesia tópica de la vía aérea. Destacamos la utilidad clínica de la videolaringoscopia en pacientes con predictores positivos para intubación difícil, la aplicabilidad del sevoflurano para el mantenimiento de la ventilación espontánea en un paciente dormido, así como el empleo de sugammadex para revertir el uso de relajantes neuromusculares en un paciente miasténico.

This is a case of a patient diagnosed with myasthenia gravis and clinical predictors of difficult intubation and ventilation undergoing emergency surgery for eventroplasty and bowel resection. The patient was successfully intubated asleep, with no neuromuscular relaxation, using a C-MAC video laryngoscope and difficult intubation d-Blade, following inhaled induction and topical anesthesia of the airway. We do want to stress the clinical value of video laryngoscopy in patients with positive predictors of difficult intubation, the applicability of Sevoflurane for the maintenance of spontaneous ventilation in a patient asleep, as well as the use of Sugammadex for reversal of neuromuscular block in a myasthenia patient.