2022 American Society of Anesthesiologists Practice Guidelines for Management of the Difficult Airway.

The American Society of Anesthesiologists; All India Difficult Airway Association; European Airway Management Society; European Society of Anaesthesiology and Intensive Care; Italian Society of Anesthesiology, Analgesia, Resuscitation and Intensive Care; Learning, Teaching and Investigation Difficult Airway Group; Society for Airway Management; Society for Ambulatory Anesthesia; Society for Head and Neck Anesthesia; Society for Pediatric Anesthesia; Society of Critical Care Anesthesiologists; and the Trauma Anesthesiology Society present an updated report of the Practice Guidelines for Management of the Difficult Airway.

A Decision Tree Approach to Airway Management Pathways in the 2022 Difficult Airway Algorithm of the American Society of Anesthesiologists.

The American Society of Anesthesiologists' (ASA) Task Force on Management of the Difficult Airway has developed a decision tree tool that uses inductive assessments to guide the anesthesiologist's choice of pathway in the ASA's Difficult Airway Algorithm. The tool prompts the anesthesiologist to consider the risk of difficulty with laryngoscopy (direct or indirect) and tracheal intubation, facemask or supraglottic ventilation, gastric contents aspiration, and rapid oxyhemoglobin desaturation. For every airway management event, the approach integrates the anesthesiologist's unique combination of experience, expertise, patient anatomy and disease, equipment availability, and other contextual conditions into the decision process. Entry into the awake intubation pathway is encouraged when the patient is judged at risk of difficult tracheal intubation and one or more of the following: difficult ventilation, significant aspiration risk, and/or rapid oxyhemoglobin desaturation. The decision tree tool is anticipated to improve communication between anesthesiologists and others by clearly identifying those factors of concern and how decision-making is affected by those concerns.

Kinking of catheters during translaryngeal jet ventilation: a bench model investigation of eight devices.

OBJECTIVE: To evaluate oxygen flow through several transtracheal devices in native and right angle kinked states. MATERIAL AND METHOD: Eight catheter-over-needle, and two oxygen conveyance devices (Enk Flow Modulator 10 L/min flow and Manujet III Jet device 15, 30, 50 psi) were examined. Oxygen flow from each catheter was measured five times with three insufflation patterns [continuous insufflation, one second insufflation/one second pause (1:1), one second insufflation/three second pause (1:3)] in both native, and 90 degree kinked condition. RESULTS: During continuous insufflation, all but the 20G catheter delivered flows of more than 7 L/m with all conveyance pressures. With a 1:1 insufflation/pause ratio, catheters smaller than 16G were able to deliver 7 L/min flow only with driving pressures of 30 and 50 psi. With a 1:3 insufflation ratio, no catheter could deliver adequate flow with 15 psi (manujet) or with the Enk Flow modulator Only the Cook catheter and 14G Ravussin were capable at 30 psi. Only the Cook Transtracheal Jet Ventilation Catheter could deliver adequate flow in kinked position, but only at 50 psi. CONCLUSION: Needle-catheters designed for vascular access are marginally capable of effective TJV. The Cook Transtracheal Jet Ventilation catheter proved to be the most robust device in the kinked state, but only when combined with a high-pressure oxygen conveyance system.

Airway Management in an Anatomically and Physiologically Difficult Airway.

A "difficult airway" should be suspected in patients with any anatomical or physiologic abnormality that might result in the loss of the airway or significant cardiopulmonary compromise upon induction of general anesthesia. Historically, an awake intubation has often been the preferred approach for airway management in these patients. Here we describe a case in which an awake intubation was safely performed in a patient with both anatomical (i.e., laryngeal mass) and physiologic (i.e., pulmonary hypertension) abnormalities. Oxygenation, airway patency, and spontaneous breathing were well maintained with successful intubation on the first attempt. We recommend that the patient's physiologic state should always be considered in airway management planning.

Airway management in a patient with Goldenhar syndrome: a case report.

Children with Goldenhar syndrome are known to present airway management challenges for the anesthesiologist. We present the case of a 10-year-old child with Goldenhar syndrome, in whom a flexible Laryngeal Mask Airway (Intavent Orthofix, Ltd, Maidenhead, UK) was successfully used for eye surgery.

The out-of-hospital esophageal and endobronchial intubations performed by emergency physicians.

BACKGROUND: Rapid establishment of a patent airway in ill or injured patients is a priority for prehospital rescue personnel. Out-of-hospital tracheal intubation can be challenging. Unrecognized esophageal intubation is a clinical disaster. METHODS: We performed an observational, prospective study of consecutive patients requiring transport by air and out-of-hospital tracheal intubation, performed by primary emergency physicians to quantify the number of unrecognized esophageal and endobronchial intubations. Tracheal tube placement was verified on scene by a study physician using a combination of direct visualization, end-tidal carbon dioxide detection, esophageal detection device, and physical examination. RESULTS: During the 5-yr study period 149 consecutive out-of-hospital tracheal intubations were performed by primary emergency physicians and subsequently evaluated by the study physicians. The mean patient age was 57.0 (+/-22.7) yr and 99 patients (66.4%) were men. The tracheal tube was determined by the study physician to have been placed in the right mainstem bronchus or esophagus in 16 (10.7%) and 10 (6.7%) patients, respectively. All esophageal intubations were detected and corrected by the study physician at the scene, but 7 of these 10 patients died within the first 24 h of treatment. CONCLUSION: The incidence of unrecognized esophageal intubation is frequent and is associated with a high mortality rate. Esophageal intubation can be detected with end-tidal carbon dioxide monitoring and an esophageal detection device. Out-of-hospital care providers should receive continuing training in airway management, and should be provided additional confirmatory adjuncts to aid in the determination of tracheal tube placement.

Prehospital airway management: a prospective evaluation of anaesthesia trained emergency physicians.

STUDY OBJECTIVE: To determine the characteristics of prehospital tracheal intubation and the incidence of difficult-to-manage airways in out-of-hospital patients managed by emergency medicine physicians with anaesthesia training. METHODS: In a prospective study, conducted over a 4-year period, we evaluated all airway interventions performed by anaesthesia-trained emergency physicians. RESULTS: One thousand, one hundred and six out of 16,559 patients (6.8%) required tracheal intubation. Orotracheal intubation was attempted in 982, laryngoscopic aided nasotracheal intubation in 64 and blind nasotracheal intubation in 90 of the cases. Two techniques were used in 30 patients. Failure rates were 2.4, 8.1 and 25.6%, respectively. A Combitube or LMA was used in 2.0%. In one case of failed Combitube insertion successful needle cricothyrotomy was performed. In patients undergoing direct laryngoscopy, Cormack-Lehane laryngeal grade views I-IV were seen in 52.0, 28.8, 12.6 and 6.6% of cases, respectively. A difficult to manage airway (DMA) was reported in 14.8%, multiple intubation attempts in 4.3% and failed intubation in 2.0% of all cases. Grouping patients based on clinical presentation revealed a significantly higher incidence of DMA in trauma patients (18.6%) and during cardiopulmonary resuscitation (16.7%) than in the remaining patient group (9.8%). Intubation failed significantly more often in trauma (3.9%) than in the remaining patient group (1.1%). CONCLUSION: When compared to studies on laryngoscopy performed in the operating room, this study demonstrated a higher incidence of difficult and failed laryngoscopy, DAM, and high laryngeal grade views when patients were managed in a prehospital setting by anaesthesia trained physicians.

The Airway Approach Algorithm: a decision tree for organizing preoperative airway information.

Anticipatory decision-making in airway management requires the integration of both history and physical examination findings. Though all airways can be managed along some branch of the American Society of Anesthesiologists' (ASA) Difficult Airway Algorithm, by predicting specific difficulties and integrating this information into an airway approach strategy, emergency branches of the ASA algorithm may be avoided. The Airway Approach Algorithm (AAA) consists of five clinical questions, with "yes" or "no" answers, to be addressed prior to the management of the airway. A positive answer to any question leads the clinician to the next, whereas a negative answer directs the operator to a root point of the ASA algorithm. The AAA is introduced with the anticipation that trainees in Anesthesiology, as well as others, will find it helpful in organizing preoperative information concerning the airway.

Preoperative planning of airway management in critical care patients.

OBJECTIVE: The aim of this article is to review aspects of airway evaluation that may affect the care of the critical care patient whose airway is to be managed. This information must then be incorporated into the decision-making process of the "airway manager." DESIGN: Literature review. RESULTS: Historically used indexes of airway evaluation suffer from low sensitivity and only modest specificity in identifying the difficult-to-intubate patient. Using each index in isolation of others contributes to their poor predictive power. An understanding of anatomical relationships that these indexes measure should help the clinician in evaluating the airway. The clinician's impression of the airway, as well as the likelihood of trouble with supraglottic ventilation, the patient's inability to take food orally, and the patient's general condition can be used to formulate a management plan. This plan should be consistent with the American Society of Anesthesiologist's difficult airway algorithm. CONCLUSIONS: Rote decision making on airway management, based on commonly used indexes, is not adequate. The vital role of airway in anesthetic management of the critical care patient demands thoughtful consideration. Patient conditions including the need for airway control, the likelihood of difficult laryngoscopy or supraglottic ventilation, the patient's inability to take food orally, and the medical state of the patient must be incorporated.

The use of the LMA-ProSeal in airway resuscitation.

Insufflation of the stomach with air can be a complication of face mask ventilation in the case of airway obstruction. Although the laryngeal mask airway has proven value in airway resuscitation, it has two major failings: a relatively low seal pressure and lack of access to the alimentary tract. A case is reported in which failed intubation (by multiple techniques) and intermittent face mask ventilation resulted in gastric distension, decreased airway compliance, and compromised gas exchange. The patient experience oxyhemoglobin saturation that did not improve despite laryngeal mask ventilation. The patient was resuscitated with a LMA-ProSeal, which permitted ventilation with high airway pressures. Return of oxyhemoglobin saturation occurred after decompression of the stomach with a gastric tube inserted via the LMA-ProSeal's gastric drain.