Evaluation of the i-gel® Plus supraglottic airway device in elective surgery: a prospective international multicentre study.

BACKGROUND: The i-gel® Plus is a modified version of the i-gel® supraglottic airway device. It contains a wider drainage port; a longer tip; ramps inside the breathing channel; and an additional port for oxygen delivery. There has been no prospective evaluation of this device in clinical practice. METHODS: This international, multicentre, prospective cohort study aimed to evaluate the performance of the i-gel Plus in adult patients undergoing elective procedures under general anaesthesia. The primary outcome was overall insertion success rate, defined as the ability to provide effective airway management through the device from insertion until the end of the surgical procedure. Secondary outcomes included device performance and incidence of postoperative adverse events. Data from the first 1000 patients are reported. RESULTS: In total, 1012 patients were enrolled; 12 forms were excluded from the final analysis due to incomplete data leaving 1000 included patients (545 female). Overall insertion success rate was 98.6%, with a first-attempt success rate of insertion of 88.2%. A significant difference between females and males was seen for the overall success rate (97.4% vs. 99.6% respectively) but not for first-attempt successful insertion. Mean (SD) oropharyngeal seal pressure was 32 (7) cmH2O. The only independent factor that increased the risk of first-attempt failure was low operator experience. Complications included desaturation < 85% in 0.6%; traces of blood on the device in 7.4%; laryngospasm in 0.5%; and gastric contents inside the bowl in 0.2% of patients. CONCLUSIONS: The i-gel Plus appears to be an effective supraglottic airway device that is associated with a high insertion success rate and a reasonably low incidence of complications.

Effective bolus dose of remimazolam for i-gel® insertion in nonparalyzed patients: a dose-finding study.

PURPOSE: Remimazolam is a recently developed ultra-short-acting benzodiazepine used for anesthesia induction and maintenance. Nevertheless, the effective bolus dose of remimazolam for i-gel® (Intersurgical Ltd., Wokingham, Berkshire, UK) insertion without the use of neuromuscular blocking agents (NMBAs) has not been well established. METHODS: This study included 25 adult patients scheduled for surgery under general anesthesia who were eligible for i-gel use. Anesthesia was induced with predetermined bolus doses of remimazolam, starting at 0.3 mg·kg-1 for the first patient, without the use of NMBAs. All patients concurrently received remifentanil using target-controlled infusion (TCI) at a fixed effect-site concentration (Ce) of 3.0 ng·mL-1. Insertion of the i-gel was attempted 90 sec after remimazolam administration, and insertion conditions were assessed. Subsequent doses of remimazolam were decreased or increased by 0.05 mg·kg-1, depending on the success or failure of i-gel insertion. RESULTS: The mean (standard deviation) 50% effective dose (ED50) of a remimazolam bolus for successful i-gel insertion as determined by the modified Dixon's up-and-down method was 0.100 (0.027) mg·kg-1. The ED50 and ED95 estimated by isotonic regression were 0.111 (83% confidence interval [CI], 0.096 to 0.131) mg·kg-1 and 0.182 (95% CI, 0.144 to 0.195) mg·kg-1, respectively. None of the patients required treatment for hypotension or bradycardia during anesthesia induction. CONCLUSION: Based on the ED95 of remimazolam bolus dose determined in our study, we recommend using 0.182 mg·kg-1 of remimazolam in combination with remifentanil TCI at a Ce of 3.0 ng·mL-1 for successful i-gel insertion without NMBAs in adult patients. This regimen seems effective with a low risk of hemodynamic instability during anesthesia induction. STUDY REGISTRATION: ClinicalTrials.gov ( NCT05298228 ); first submitted 6 March 2022.

RéSUMé: OBJECTIF: Le remimazolam est une benzodiazépine à action ultra-courte récemment mise au point et utilisée pour l'induction et le maintien de l'anesthésie. Toutefois, la dose efficace en bolus de remimazolam pour l'insertion de l'i-gel® (Intersurgical Ltd., Wokingham, Berkshire, Royaume-Uni) sans utiliser de bloqueurs neuromusculaires (BNM) n'a pas été bien établie. MéTHODE: Cette étude a inclus 25 adultes devant bénéficier d'une intervention chirurgicale sous anesthésie générale qui étaient éligibles à l'utilisation d'un i-gel. L'anesthésie a été induite avec des doses prédéterminées en bolus de remimazolam, à partir de 0,3 mg·kg−1 pour la première personne, sans utiliser de BNM. Toutes les personnes anesthésiées ont reçu en parallèle du rémifentanil en perfusion à objectif de concentration à une concentration au site effecteur (Ce) de 3,0 ng·mL−1. L'insertion de l'i-gel a été tentée 90 secondes après l'administration de remimazolam, et les conditions d'insertion ont été évaluées. Les doses subséquentes de remimazolam ont été diminuées ou augmentées de 0,05 mg·kg−1, en fonction du succès ou de l'échec de l'insertion de l'i-gel. RéSULTATS: La dose efficace moyenne (écart type) de 50 % (DE50) d'un bolus de remimazolam pour une insertion réussie de l'i-gel, telle que déterminée par la méthode « up-and-down ¼ de Dixon modifiée, était de 0,100 (0,027) mg·kg−1. Les DE50 et DE95 estimées par régression isotonique étaient de 0,111 (intervalle de confiance [IC] à 83 %, 0,096 à 0,131) mg·kg−1 et 0,182 (IC 95 %, 0,144 à 0,195) mg·kg−1, respectivement. Aucun·e patient·e n'a eu besoin de traitement pour une hypotension ou une bradycardie pendant l'induction de l'anesthésie. CONCLUSION: D'après la DE95 de la dose de remimazolam en bolus déterminée dans notre étude, nous recommandons d'utiliser 0,182 mg·kg−1 de remimazolam en association avec une perfusion à objectif de concentration de rémifentanil à une Ce de 3,0 ng·mL−1 pour réussir l'insertion de l'i-gel sans BNM chez la patientèle adulte. Ce schéma semble efficace avec un faible risque d'instabilité hémodynamique lors de l'induction de l'anesthésie. ENREGISTREMENT DE L'éTUDE: ClinicalTrials.gov (NCT05298228); première soumission le 6 mars 2022.

Comparing leak pressure of LMA® ProSeal™ versus i-gel® at head rotation: a randomized controlled trial.

PURPOSE: The effect of head rotation on supraglottic airway (SGA) oropharyngeal leak pressure (OPLP) has not been well elucidated. The aim of this study was to help clarify which SGA device provides higher OPLP at head-rotated position. METHODS: Patients who underwent elective surgery under general anesthesia were enrolled and randomly divided into laryngeal mask airway (LMA®) ProSeal™ and i-gel® groups. The allocated SGA device was inserted under anesthesia. The primary outcome was OPLP, and secondary outcomes were ventilation score, expiratory tidal volume, and maximum pressure under volume-controlled ventilation (VCV) with an inspiratory tidal volume of 10 mL·kg-1 ideal body weight and fibreoptic view of the vocal cords at 0°, 30°, and 60° head rotation. RESULTS: Data from 78 and 76 patients were analyzed in the LMA ProSeal and i-gel groups, respectively. The mean (standard deviation) OPLP of the LMA ProSeal was significantly higher than that of the i-gel at the 60° head-rotated position (LMA ProSeal, 20.4 [6.5] vs i-gel, 16.9 [7.8] cm H2O; difference in means, 3.6; adjusted 95% confidence interval, 0.5 to 6.6; adjusted P = 0.02, adjusted for six comparisons). The maximum pressure under VCV at 60° head rotation was significantly higher in the LMA ProSeal group than in the i-gel group. The expiratory tidal volume of the LMA ProSeal did not significantly change with head rotation and was significantly higher than that of the i-gel at 60° head rotation. Ventilation score, fibreoptic view of the vocal cords, and complications were not significantly different between the ProSeal and i-gel groups. CONCLUSIONS: The LMA ProSeal provides higher OPLP than the i-gel at a 60° head-rotated position under general anesthesia. TRIAL REGISTRATION: Japan Registry of Clinical Trials (https://jrct.niph.go.jp) (JRCT1012210043); registered 18 October 2021.

RéSUMé: OBJECTIF: L'effet de la rotation de la tête sur la pression de fuite oropharyngée (OPLP en anglais) des dispositifs supraglottiques (DSG) n'est pas encore bien élucidé. L'objectif de cette étude était d'aider à déterminer quel DSG procurait une pression de fuite oropharyngée plus élevée lorsque la tête est en rotation. MéTHODE: Les patient·es qui ont bénéficié d'une intervention chirurgicale non urgente sous anesthésie générale ont été recruté·es et aléatoirement réparti·es en deux groupes, soit masque laryngé (LMA®) ProSeal™ ou i-gel®. Le DSG alloué a été inséré sous anesthésie. Le critère d'évaluation principal était la pression de fuite oropharyngée, et les critères d'évaluation secondaires étaient le score de ventilation, le volume courant expiratoire et la pression maximale sous ventilation à volume contrôlé (VVC) avec un volume courant inspiratoire de 10 mL·kg−1 du poids corporel idéal et une visualisation fibroscopique des cordes vocales à une rotation de la tête de 0°, 30° et 60°. RéSULTATS: Les données de 78 et 76 patient·es ont été analysées dans les groupes LMA ProSeal et i-gel, respectivement. La pression de fuite oropharyngée moyenne (écart type) du LMA ProSeal était significativement plus élevée que celle de l'i-gel en position de rotation de la tête à 60° (LMA ProSeal, 20,4 [6,5] vs i-gel, 16,9 [7,8] cm H2O; différence de moyennes, 3,6; intervalle de confiance ajusté à 95 %, de 0,5 à 6,6; P = 0,02 ajusté, ajusté pour six comparaisons). La pression maximale sous VVC à une rotation de la tête de 60° était significativement plus élevée dans le groupe LMA ProSeal que dans le groupe i-gel. Le volume courant expiratoire du LMA ProSeal n'a pas changé de manière significative avec la rotation de la tête et était significativement plus élevé que celui de l'i-gel à une rotation de la tête de 60°. Le score de ventilation, la visualisation fibroscopique des cordes vocales et les complications n'étaient pas significativement différents entre les groupes ProSeal et i-gel. CONCLUSION: Le LMA ProSeal procure une pression de fuite oropharyngée plus élevée que l'i-gel dans une position de rotation de la tête à 60° sous anesthésie générale. ENREGISTREMENT DE L'éTUDE: Registre japonais des essais cliniques (https://jrct.niph.go.jp) (JRCT1012210043); enregistré le 18 octobre 2021.

Comparison of Laryngeal Mask Airway Seal Between Anesthesiologists and Individuals Without Previous Airway Experience.

BACKGROUND: Tracheal intubation is the gold standard for airway management in emergency medicine, but more difficult to apply for inexperienced individuals than laryngeal mask airway (LMA). OBJECTIVE: The aim of our study was to investigate if inexperienced individuals are able to secure the airway with the help of LMA after a short introduction. A second aim was to evaluate Thiel-fixed specimens against unfixed ones. METHODS: In a body donor model, LMA application was evaluated between medical students without previous airway experience and anesthesiologists by comparing the sealing of the larynx using a water column applied to the esophagus. RESULTS: LMAs were successfully applied in 46 out of 55 (83.6%) attempts by medical students and in 30 out of 39 (76.9%) attempts by anesthesiologists. Among medical students, 14.1% of all LMA applications were primarily leaky, compared with 18.8% in anesthesiologists. Esophageal sealing was better in Thiel-fixed specimens (leakage 10.9%) compared with unfixed specimens (leakage 22.9%). Our data showed no significant difference between anesthesiologists and medical students in terms of sealing of LMA. Therefore, we conclude that medical students without previous airway experience can quickly learn to apply LMA sufficiently and thus, achieve aspiration protection similar to anesthesiologists. CONCLUSION: Medical students without previous airway experience can successfully insert LMAs after a short introduction. Thiel-fixed specimens are suitable for studies as well as for training in LMA application.

Aerosol generation with the use of positive pressure ventilation via supraglottic airway devices: an observational study.

The amount of aerosol generation associated with the use of positive pressure ventilation via a supraglottic airway device has not been quantified. We conducted a two-group, two-centre, prospective cohort study in which we recruited 21 low-risk adult patients scheduled for elective surgery under general anaesthesia with second-generation supraglottic airway devices. An optical particle sizer and an isokinetic sampling probe were used to record particle concentrations per second at different size distributions (0.3-10 µm) during use as well as baseline levels during two common activities (conversation and coughing). There was a median (IQR [range]) peak increase of 2.8 (1.5-4.5 [1-28.1]) and 4.1 (2.0-7.1 [1-18.2]) times background concentrations during SAD insertion and removal. Most of the particles generated during supraglottic airway insertion (85.0%) and removal (85.3%) were < 3 µm diameter. Median (IQR [range]) aerosol concentration generated by insertion (1.1 (0.6-5.1 [0.2-22.3]) particles.cm-3 ) and removal (2.1 (0.5-3.0 [0.1-18.9]) particles.cm-3 ) of SADs were significantly lower than those produced during continuous talking (44.5 (28.3-70.5 [2.0-134.5]) particles.cm-3 ) and coughing (141.0 (98.3-202.8 [4.0-296.5]) particles.cm-3 ) (p < 0.001). The aerosol levels produced were similar with the two devices. The proportion of easily inhaled and small particles (<1 µm) produced during insertion (57.5%) and removal (57.5%) was much lower than during talking (99.1%) and coughing (99.6%). These results suggest that the use of supraglottic airway devices in low-risk patients, even with positive pressure ventilation, generates fewer aerosols than speaking and coughing in awake patients.

Postoperative pulmonary complications in older patients undergoing elective surgery with a supraglottic airway device or tracheal intubation.

The two most commonly used airway management techniques during general anaesthesia are supraglottic airway devices and tracheal tubes. In older patients undergoing elective non-cardiothoracic surgery under general anaesthesia with positive pressure ventilation, we hypothesised that a composite measure of in-hospital postoperative pulmonary complications would be less frequent when a supraglottic airway device was used compared with a tracheal tube. We studied patients aged ≥ 70 years in 17 clinical centres. Patients were allocated randomly to airway management with a supraglottic airway device or a tracheal tube. Between August 2016 and April 2020, 2900 patients were studied, of whom 2751 were included in the primary analysis (1387 with supraglottic airway device and 1364 with a tracheal tube). Pre-operatively, 2431 (88.4%) patients were estimated to have a postoperative pulmonary complication risk index of 1-2. Postoperative pulmonary complications, mostly coughing, occurred in 270 of 1387 patients (19.5%) allocated to a supraglottic airway device and 342 of 1364 patients (25.1%) assigned to a tracheal tube (absolute difference -5.6% (95%CI -8.7 to -2.5), risk ratio 0.78 (95%CI 0.67-0.89); p < 0.001). Among otherwise healthy older patients undergoing elective surgery under general anaesthesia with intra-operative positive pressure ventilation of their lungs, there were fewer postoperative pulmonary complications when the airway was managed with a supraglottic airway device compared with a tracheal tube.

Remimazolam dose for successful insertion of a supraglottic airway device with opioids: a dose-determination study using Dixon's up-and-down method.

PURPOSE: Remimazolam, an ultra-short-acting benzodiazepine, was recently approved in numerous jurisdictions as an induction drug for general anesthesia. We aimed to determine the doses of remimazolam that would allow placement of a supraglottic airway device (SGD) in 50% and 95% of nonparalyzed patients (ED50 and ED95). METHODS: In this prospective study, 30 American Society of Anesthesiology Physical Status I-II grade female patients scheduled for hysteroscopic surgery were enrolled. Anesthesia was induced with 1 µg·kg-1 of fentanyl and continuous infusion of remimazolam without neuromuscular blockade. An i-gel® SGD was inserted 2.5 min after the start of remimazolam infusion. We used Dixon's up-and-down method and isotonic regression to determine the ED50 and ED95 of remimazolam for insertion of an SGD. RESULTS: Twenty-eight patients were included in the final analysis. The ED50 and ED95 of remimazolam required for successful i-gel insertion were 8.8 mg·kg-1·hr-1 (95% confidence interval [CI], 6.3 to 10.6) and 10.7 mg·kg-1·hr-1 (95% CI, 10.6 to 11.7), respectively. A nonfully relaxed jaw was found in 7/13 patients (54%) in the success group and 14/15 patients (93%) in the failure group (difference in proportions, 40%; 95% CI, 7 to 65; P = 0.02). Bucking or other movements during SGD insertion only occurred in the failure group (11/15, 73%). CONCLUSION: In 95% of nonparalyzed female patients undergoing hysteroscopy, 10.7 mg·kg-1·hr-1 of remimazolam with 1 µg·kg-1 of fentanyl facilitates i-gel insertion. Remimazolam showed a high incidence of poor jaw relaxation and bucking or other movements during SGD insertion. STUDY REGISTRATION: Clinical Trial Registry of the Republic of Korea (KCT0006527, https://cris.nih.go.kr ; registered 1 September 2021; principal investigator: Ji Seon Jeong).

RéSUMé: OBJECTIF: Le remimazolam, une benzodiazépine à action ultra-brève, a récemment été approuvé dans de nombreuses juridictions comme agent d'induction pour l'anesthésie générale. Notre objectif était de déterminer les doses de remimazolam qui permettraient l'insertion d'un dispositif supraglottique (DSG) chez 50 % et 95 % des patients non paralysés (DE50 et DE95). MéTHODE: Dans cette étude prospective, 30 patientes de statut physique I-II selon l'American Society of Anesthesiology devant bénéficier d'une chirurgie hystéroscopique ont été recrutées. L'anesthésie a été induite avec 1 µg·kg−1 de fentanyl et une perfusion continue de remimazolam sans bloc neuromusculaire. Un DSG i-gel® a été inséré 2,5 minutes après l'amorce de la perfusion de remimazolam. Nous avons utilisé la méthode de l'escalier de Dixon et la régression isotonique pour déterminer la DE50 et DE95 de remimazolam pour l'insertion d'un DSG. RéSULTATS: Vingt-huit patientes ont été incluses dans l'analyse. Les DE50 et DE95 du remimazolam requises pour une insertion réussie de l'i-gel était de 8,8 mg·kg−1·h−1 (intervalle de confiance [IC] à 95 %, 6,3 à 10,6) et 10,7 mg·kg−1·h−1 (IC 95 %, 10,6 à 11,7), respectivement. Une mâchoire non complètement détendue a été observée chez 7 patientes sur 13 (54 %) dans le groupe d'intubation réussie et chez 14/15 patientes (93 %) dans le groupe d'échec d'intubation (différence de proportions, 40 %; IC 95 %, 7 à 65; P = 0,02). Le fléchissement ou d'autres mouvements pendant l'insertion du DSG ne se sont produits que dans le groupe d'échec de l'induction (11/15, 73 %). CONCLUSION: Chez 95 % des patientes non paralysées bénéficiant d'une hystéroscopie, 10,7 mg·kg−1·h−1 de remimazolam avec 1 µg·kg−1 de fentanyl ont facilité l'insertion d'un dispositif i-gel. Le remimazolam a montré une incidence élevée de mauvaise relaxation de la mâchoire et de fléchissement ou d'autres mouvements lors de l'insertion du DSG. ENREGISTREMENT DE L'éTUDE: Registre des essais cliniques de la République de Corée (KCT0006527, https://cris.nih.go.kr ; enregistrée le 1er septembre 2021; chercheur principal : Ji Seon Jeong).

Effect of superior laryngeal nerve block in alleviating sore throat after application of i-gel supraglottic airway: a randomized controlled trial.

BACKGROUND: Postoperative sore throat (POST) is a common complaint after supraglottic airway device (SAD) application. Internal branch of the superior laryngeal nerve (iSLN) block has the potential to alleviate POST. The aim of this trial was to explore the effect of iSLN block in alleviating sore throat, as well as to identify the potential risk factors for POST after SAD insertion. METHODS: One hundred thirty-four patients scheduled for elective gynecological surgery were randomized to either group T: tetracaine syrup (1%) for local lubrication on i-gel supraglottic device (n = 67) or group B: i-gel insertion with water based lubricant on it and followed by bilateral iSLN block (ropivacaine, 0.375%, 2 ml for each side) (n = 67). Under ultrasound guidance, iSLN was exposed below thyrohyoid membrane. The primary outcome was the intensity of sore throat at 6 h after surgery. In addition, POST score at 0.5 h and 24 h, the severity of postoperative swallowing discomfort, acoustic analysis and complications were measured. RESULTS: Compared with tetracaine syrup for local lubrication, iSLN block resulted in a reduced intensity of POST at 0.5 h (P = 0.044, OR = 1.99, 95%CI 1.02 to 3.88) and 6 h (P < 0.001, OR = 5.07, 95%CI 2.53 to 10.14) after surgery, as well as less severity of swallowing discomfort (P < 0.001, OR = 2.21, 95%CI 1.63 to 2.99) and cough (P = 0.039, OR = 1.97, 95%CI 1.04 to 3.73). The patients after iSLN block presented lower jitter and shimmer value in acoustic analysis at 6 h after surgery (P < 0.001). CONCLUSIONS: iSLN block was effective in alleviating POST, improving voice function, as well as reducing postoperative swallowing discomfort and coughing. TRIAL REGISTRATION: Chinese Clinical Trial Registry (ChiCTR2000037974) on 8th Sept 2020.

The effect of class 3 obesity on the functionality of supraglottic airway devices: a historical cohort analysis with propensity score matching.

PURPOSE: Supraglottic airway devices (SGAs) have been increasingly used as a primary airway in patients undergoing anesthesia as an alternative to endotracheal tubes. Second-generation devices have expanded their applicability to include uses in patients with obesity. Nevertheless, there is limited evidence of SGA suitability for patients with class 3 obesity (body mass index [BMI] ≥ 40 kg·m-2). As such, we compared rates of SGA functionality between patients with class 3 obesity and patients without class 3 obesity undergoing general anesthesia. METHODS: We performed a propensity score matching analysis using inverse probability of treatment weighting to compare the functionality of SGAs in adult patients with class 3 obesity vs without class 3 obesity. These patients underwent surgery at a hospital in Queensland, Australia from November 2017 to September 2020 and had a SGA inserted as part of their anesthetic care. All data were collected from patients' electronic medical records. We included 321 patients in the cohort with class 3 obesity and 471 in the cohort without class 3 obesity (control/comparison). The estimated effect of class 3 obesity on SGAs was calculated using adjusted odds ratios (AORs) with their 95% confidence intervals (CIs). RESULTS: The overall weighted prevalence of nonfunctional SGAs was 3.2%, with a significantly higher rate in the class 3 obesity cohort compared with the control cohort (4.7% vs 2.1%) (P = 0.04). This adjusted analysis illustrates that class 3 obesity was associated with an almost four times higher odds of a nonfunctional SGA (odds ratio [OR], 2.3; 95% CI, 1.0 to 5.1; AOR, 3.9; 95% CI, 1.4 to 10.6) than patients without class 3 obesity. CONCLUSION: Patients with class 3 obesity (BMI ≥ 40 kg·m-2) had greater than three-fold odds of nonfunctional intraoperative SGAs than patients without class 3 obesity.

RéSUMé: OBJECTIF: Les dispositifs supraglottiques (DSG) sont de plus en plus utilisés comme accès primaire aux voies aériennes en tant qu'alternative aux sondes endotrachéales chez les patient·es bénéficiant d'une anesthésie. Les dispositifs de deuxième génération ont élargi leur applicabilité pour inclure des utilisations chez les personnes souffrant d'obésité. Néanmoins, il existe des données probantes limitées concernant l'adéquation des DSG pour la patientèle souffrant d'obésité de classe 3 (indice de masse corporelle [IMC] ≥ 40 kg·m­2). Pour cette raison, nous avons comparé les taux de fonctionnalité des DSG entre une patientèle souffrant d'obésité de classe 3 et une patientèle sans obésité de classe 3 bénéficiant d'une anesthésie générale. MéTHODE: Nous avons réalisé une analyse d'appariement des scores de propension en utilisant la probabilité inverse de pondération du traitement pour comparer la fonctionnalité des DSG chez la patientèle adulte atteinte d'obésité de classe 3 vs sans obésité de classe 3. Ces patient·es ont bénéficié d'une intervention chirurgicale dans un hôpital du Queensland, en Australie, entre novembre 2017 et septembre 2020, et un DSG a été inséré dans le cadre de leurs soins anesthésiques. Toutes les données ont été recueillies à partir des dossiers médicaux informatisés des patient·es. Nous avons inclus 321 personnes dans la cohorte souffrant d'obésité de classe 3 et 471 dans la cohorte sans obésité de classe 3 (témoin/comparaison). L'effet estimé de l'obésité de classe 3 sur les DSG a été calculé à l'aide de rapports de cotes ajustés (RCA) avec leurs intervalles de confiance (IC) de 95%. RéSULTATS: La prévalence pondérée globale des DSG non fonctionnels était de 3,2 %, avec un taux significativement plus élevé dans la cohorte avec obésité de classe 3 que dans la cohorte témoin (4,7 % vs 2,1 %) (P = 0,04). Cette analyse ajustée illustre que l'obésité de classe 3 était associée à un risque presque quadruplé de non-fonctionnalité du DSG (rapport de cotes [RC], 2,3; IC 95 %, 1,0 à 5,1; RCA, 3,9; IC 95 %, 1,4 à 10,6) que chez des patient·es sans obésité de classe 3. CONCLUSION: Les personnes atteintes d'obésité de classe 3 (IMC ≥ 40 kg·m­2) présentaient plus de trois fois plus de risque de non-fonctionnalité péropératoire de DSG que les personnes sans obésité de classe 3.

Comparison of standard weight-based and thenar eminence dimension-based selection of I-gel in pediatric patients - A randomized controlled study.

Background and Aim: Supraglottic airway devices are increasingly being used for airway management. I-gel is being widely used even for pediatric patients. Although the weight-based selection of the size of the device seems to be the standard technique, this method may not be possible in all patients. The aim of the study was to compare the standard weight-based method with the thenar eminence dimension-based method for I-gel selection. Material and Methods: A prospective randomized study was conducted on 74 pediatric patients of either sex, aged between 6 months and 15 years, belonging to American Society of Anesthesiologists (ASA) physical status I, II, and III and who were posted for various surgical procedures under general anesthesia. The study population was divided into two groups of 37 patients each. I-gel was inserted based on weight in group A patients and based on thenar eminence size in group B patients. Parameters like first attempt success rate, ease of insertion, and complications were compared between the two groups using Student's t-test and Chi-square test. Results: The demographic values between the groups were comparable. The first attempt success rate was 97.4% in group A and 91.7% in group B (P = 0.358). Insertion of I-gel was unsuccessful in two patients in group B. Two patients of group B had blood staining of the device. None of the patients had complications related to insertion. Conclusion: The thenar eminence dimension can be used instead of weight while choosing the size of I-gel in pediatric patients. None of the patients had complications related to device insertion.

Comparison of SaCoVLM™ video laryngeal mask-guided intubation and i-gel combined with flexible bronchoscopy-guided intubation in airway management during general anesthesia: a non-inferiority study.

BACKGROUND: When a difficult airway is unanticipatedly encountered and the initial laryngoscopic intubation fails, a supraglottic airway device (SAD) may be placed to aid ventilation and oxygenation, and act as a conduit for intubation. SaCoVLM™, as new SAD, can offer a direct vision to guide intubation. However, no study has evaluated the performance of SaCoVLM™ video laryngeal mask (VLM) intubation and i-gel combined with flexible bronchoscopy (FB)-guided intubation in airway management during general anesthesia. METHODS: A total of 120 adult patients were randomly allocated into the SaCoVLM™ group (Group S) and i-gel group (Group I). After induction of general anesthesia, guided tracheal intubation under direct vision of the SaCoVLM™ was conducted in Group S, while Group I received FB-guided tracheal intubation using the i-gel. The success rate of SAD placement, first-pass success rate of guided tracheal tube placement, and total success rate in both groups were recorded. The time for SAD placement, time for guided tracheal intubation, total intubation time (time for SAD placement and intubation), glottic exposure grading and postoperative intubation complications (i.e., dysphagia, hoarseness, pharyngalgia, etc.) of both groups were also compared. RESULTS: The first-time success rate of SAD placement was 98% in two groups. The first-pass success rate of guided endotracheal intubation was 92% in Group S and 93% in Group I (P = 0.74 > 0.05). The total intubation time was 30.8(± 9.7) s and 57.4(± 16.6) s (95% CI = -31.5 to -21.7) in Group S and Group I, respectively (P < 0.01). The total complication rate was 8% in Group S and 22% in Group I (P < 0.05). The laryngeal inlet could be observed in the S group through the visual system of SaCoVLM™. No dysphagia or hoarseness was reported. CONCLUSION: SaCoVLM™ can reveal the position of laryngeal inlet, thus providing direct vision for tracheal intubation. SaCoVLM™ -guided intubation is faster, and does not rely on FB, compared to i-gel combined with FB-guided intubation. Besides, SaCoVLM™ has a lower post-intubation complication rate. TRIAL REGISTRATION: Chinese Clinical Trials Registry (ChiCTR2100043443); Date of registration: 18/02/2021.

Prehospital Use of the Esophageal Tracheal Combitube Supraglottic Airway Device: A Retrospective Cohort Study.

BACKGROUND: In the province of Quebec (Canada), paramedics use the esophageal tracheal Combitube (ETC) for prehospital airway management. OBJECTIVES: Our main objective was to determine the proportion of patients with successful ventilation achieved after ETC use. Our secondary aim was to determine the number of ETC insertion attempts required to ventilate the patient. METHOD: This is a retrospective cohort study. All patients who had ≥1 attempt to insert an ETC during prehospital care between January 1, 2017 and December 31, 2018 were included. Prehospital and in-hospital data were extracted. Successful ventilation was defined as thorax elevation, lung sounds on chest auscultation, or positive end-tidal capnography after ETC insertion. RESULTS: A total of 580 emergency medical services interventions (99.3% cardiac arrests) were included. Most patients were men (62.5%) with a mean age 67.0 years (SD 17.6 years), and 35 (13.1%) of the 298 patients transported to emergency department survived to hospital discharge. Sufficient information to determine whether ventilation was successful or not was available for 515 interventions. Ventilation was achieved during 427 (82.7%) of these interventions. The number of ETC insertion attempts was available for 349 of the 427 successful ETC use. Overall, the first insertion resulted in successful ventilation during 294 interventions for an overall proportion of first-pass success ranging between 57.1% and 72.1%. CONCLUSION: Proportions of successful ventilation and ETC first-pass success are lower than those reported in the literature with supraglottic airway devices. The reasons explaining these lower rates and their impact on patient-centered outcomes need to be studied.

Features of new vision-incorporated third-generation video laryngeal mask airways.

Numerous studies have shown that blindly inserted supraglottic airway devices (SADs) are sub-optimally placed in 50 to 80% of all cases. Placement under direct vision has been recommended. We describe the very first two new SADs of the third generation that incorporate a videoscope with flexible tip. Both devices are made up of two interlocking components-the SAD and a videoscope. The 3rd generation, direct vision SADs allow vision-guided insertion, corrective manoeuvres, if needed, and correct placement in the hypopharynx and possess additional features which permit insertion of a gastric tube and endotracheal intubation should the need arise. This article describes the two new devices' physical characteristics, features, rationale for use, advantages and limitations in comparison to existing devices. Each of the two new devices-the Video Laryngeal Mask (VLMTM, UE Medical®) and the SafeLM® Video Laryngeal Mask System (SafeLMTM VLMS, Magill Medical Technology®) consist of two parts: (a) a disposable 2nd generation SAD with a silicone cuff and an anatomically curved tube; and (b) a reusable patient-isolated videoscope and monitoring screen, with the flexible scope located into a specially-designed, blind-end channel terminating in the bowl of the SAD, preventing the videoscope from contacting patient body fluids in the SAD bowl. Third generation placement-under-direct-vision supraglottic airway devices possess several theoretical safety and ease of use advantages which now need to be validated in clinical use.

Besdata Video Laryngeal Mask (BD-VLM)- a New Vision-Incorporated 3rd Generation Video Laryngeal Mask Airway : Dear editor.

Since the recent editorial 2, we were approached to evaluate another video laryngeal mask airway - the Besdata Video Laryngeal Mask (BD-VLM) TM, which has a different design concept, specifications and characteristics (Figure 1) compared to the other two.

Supraglottic airway device versus tracheal intubation and the risk of emergent postoperative intubation after general anaesthesia in adults: a retrospective cohort study.

BACKGROUND: We examined the association between emergent postoperative tracheal intubation and the use of supraglottic airway devices (SGAs) vs tracheal tubes. METHODS: We included data from adult noncardiac surgical cases under general anaesthesia between 2008 and 2018. We only included cases (n=59 991) in which both airways were deemed to be feasible options. Multivariable logistic regression, instrumental variable analysis, propensity matching, and mediation analysis were used. RESULTS: Use of a tracheal tube was associated with a higher risk of emergent postoperative intubation (adjusted absolute risk difference [ARD]=0.80%; 95% confidence interval (CI), 0.64-0.97; P<0.001), and a higher risk of post-extubation hypoxaemia (ARD=3.9%; 95% CI, 3.4-4.4; P<0.001). The effect was modified by the use of non-depolarising neuromuscular blocking agents (NMBAs); mediation analyses revealed that 28.9% (95% CI, 14.4-43.4%; P<0.001) of the main effect was attributable to NMBA. Airway management modified the association of NMBA and risk of emergent postoperative intubation (Pinteraction=0.02). Patients managed with an SGA had higher odds of NMBA-associated reintubation compared to patients managed with a tracheal tube (adjusted odds ratio [aOR]=3.65, 95% CI, 1.99-6.67 vs aOR=1.68, 95% CI, 1.29-2.18 [P<0.001], respectively). CONCLUSIONS: In patients undergoing procedures under general anaesthesia that could be managed with either SGA or tracheal tube, use of an SGA was associated with lower risk of emergent postoperative intubation. The effect can partly be explained by use of NMBAs. Use of NMBAs in patients with an SGA appears to increase the risk of emergent postoperative intubation.

A quantitative evaluation of aerosol generation during supraglottic airway insertion and removal.

Many guidelines consider supraglottic airway use to be an aerosol-generating procedure. This status requires increased levels of personal protective equipment, fallow time between cases and results in reduced operating theatre efficiency. Aerosol generation has never been quantitated during supraglottic airway use. To address this evidence gap, we conducted real-time aerosol monitoring (0.3-10-µm diameter) in ultraclean operating theatres during supraglottic airway insertion and removal. This showed very low background particle concentrations (median (IQR [range]) 1.6 (0-3.1 [0-4.0]) particles.l-1 ) against which the patient's tidal breathing produced a higher concentration of aerosol (4.0 (1.3-11.0 [0-44]) particles.l-1 , p = 0.048). The average aerosol concentration detected during supraglottic airway insertion (1.3 (1.0-4.2 [0-6.2]) particles.l-1 , n = 11), and removal (2.1 (0-17.5 [0-26.2]) particles.l-1 , n = 12) was no different to tidal breathing (p = 0.31 and p = 0.84, respectively). Comparison of supraglottic airway insertion and removal with a volitional cough (104 (66-169 [33-326]), n = 27), demonstrated that supraglottic airway insertion/removal sequences produced <4% of the aerosol compared with a single cough (p < 0.001). A transient aerosol increase was recorded during one complicated supraglottic airway insertion (which initially failed to provide a patent airway). Detailed analysis of this event showed an atypical particle size distribution and we subsequently identified multiple sources of non-respiratory aerosols that may be produced during airway management and can be considered as artefacts. These findings demonstrate supraglottic airway insertion/removal generates no more bio-aerosol than breathing and far less than a cough. This should inform the design of infection prevention strategies for anaesthetists and operating theatre staff caring for patients managed with supraglottic airways.

Temporomandibular joint dysfunction following the use of a supraglottic airway device during general anaesthesia: a prospective observational study.

Supraglottic airway devices are commonly used to manage the airway during general anaesthesia. There are sporadic case reports of temporomandibular joint dysfunction and dislocation following supraglottic airway device use. We conducted a prospective observational study of adult patients undergoing elective surgery where a supraglottic airway device was used as the primary airway device. Pre-operatively, all participants were asked to complete a questionnaire involving 12 points adapted from the Temporomandibular Joint Scale and the Liverpool Oral Rehabilitation Questionnaire. Objective measurements included inter-incisor distance as well as forward and lateral jaw movements. The primary outcome was the inter-incisor distance, an accepted measure of temporomandibular joint mobility. Both the questionnaire and measurements were repeated in the postoperative period and we analysed data from 130 participants. Mean (SD) inter-incisor distance in the pre- and postoperative period was 46.5 (7.2) mm and 46.3 (7.5) mm, respectively (p = 0.521) with a difference (95%CI) of 0.2 (-0.5 to 0.9) mm. Mean (SD) forward jaw movement in the pre- and postoperative period was 3.6 (2.4) mm and 3.9 (2.4) mm, respectively (p = 0.018). Mean (SD) lateral jaw movement to the right in the pre- and postoperative period was 8.9 (4.1) mm and 9.1 (4.0) mm, respectively (p = 0.314). Mean (SD) lateral jaw movement to the left in the pre- and postoperative period was 8.8 (4.0) mm and 9.3 (3.6) mm, respectively (p = 0.008). The number of patients who reported jaw clicks or pops before opening their mouth as wide as possible was 28 (21.5%) vs. 12 (9.2%) in the pre- and postoperative period, respectively (p < 0.001) with a difference (95%CI) of 12.3% (6.7-17.9%). There was no significant difference in the responses to the other 11 questions or in the number of patients who reported pain in the temporomandibular joint area postoperatively. No clinically significant dysfunction of the temporomandibular joint following the use of supraglottic airway devices in the postoperative period was identified by either patient questionnaires or objective measurements.

LMA® protector™ in patients undergoing laparoscopic surgeries: a multicenter prospective observational study.

BACKGROUND: Laryngeal masks airway (LMA) has been increasingly used in surgical patients. However, the use of LMA in laparoscopic surgeries remains controversial. The major concerns include the potential risk of esophageal regurgitation, aspiration, and difficulties to achieve effective ventilation. The aim of this study was to evaluate the safety and effectiveness of the LMA® Protector™ in patients undergoing laparoscopic surgery. METHODS: Patients aged 18 to 70 years, scheduled for laparoscopic surgeries were included. The insertion time, successful insertion rate, and oropharyngeal leak pressure were measured. Airway complications and airway manipulations during the procedure were documented. Effective ventilation rate was calculated. Visible bloodstains and reflux content in the drainage channel were documented after the removal of LMA® Protector™. RESULTS: Three hundred patients were enrolled. The insertion of LMA® Protector™ failed in seven patients resulting with a successful insertion rate of 97.7%. During the maintenance of anesthesia, airway manipulation was required in 19 patients (19/293, 6.48%), in three of whom the LMA was replaced with endotracheal intubation resulting with an effective ventilation rate of 96.7% (290/300). The oropharyngeal leak pressure was 30.18 ± 5.88 cmH2O. Seventy-five patients (25.86%) reported mild sore throat on the first day after surgery. Bloodstains on study devices were noticed in 58 patients (20%). Seventy-five patients (25.86%) reported mild sore throat on the first day after surgery. Gastric reflux was noticed in the drainage tube in 5 patients (1.72%) with no signs of aspiration in any of those patients. CONCLUSIONS: The LMA® Protector™ was shown to be safe and effective in patients undergoing laparoscopic surgeries. Although minor complications that require no further treatment, no clinically diagnosed aspiration was noticed in our study. Gastric reflux was noticed in the drainage tube in five patients undergoing laparoscopic gynecology surgery. Further research is needed to verify whether LMA® Protector™ is suitable for procedures in Trendelenburg position or other situations that a high risk of gastroesophageal reflux exists. TRIAL REGISTRATION: The trial was registered at the Chinese Clinical Trial Registry ( ChiCTR1800018300 , date of registration: September 2018).

Dimensional compatibility and limitations of tracheal intubation through supraglottic airway devices: a mannequin-based in vitro study.

BACKGROUND: Flexible bronchoscope-guided tracheal intubation through supraglottic airway devices (SGAs) is a well-established element of difficult intubation algorithms. Success can be limited by dimensional incompatibilities between tracheal tubes (TTs) and SGAs. METHODS: In this in vitro study, we tested the feasibility of TT passage through SGAs, removal of SGAs over TTs, and the ability to guide the flexible bronchoscope with 13 TT brands (internal diameter, 6.5-8.0 mm) and ten different SGAs (#4 and #5) in an intubation mannequin. RESULTS: We tested 1,040 combinations of SGAs and TTs. Tracheal tube passage failed in 155 (30%) combinations of the five tested first-generation SGAs (117 [46%] with SGA #4, 38 [15%] with SGA #5) and in three (0.6%) combinations of the five tested second-generation SGAs (two [0.8%] with SGA #4 and one [0.4%] with SGA #5). The reason for failed passage of a TT through a first-generation SGA consistently was a too-narrow SGA connector. Removal of the SGA over the TT in the 882 remaining combinations was impossible for all sizes of reinforced TTs, except the Parker Reinforced TT, and was possible for all non-reinforced TTs. Only one combination with SGA #4 and 84 combinations with SGA #5 were not ideal to adequately guide the flexible bronchoscope. CONCLUSION: Clinically relevant combinations of adult-size TTs and SGAs can be incompatible, rendering flexible bronchoscope-guided tracheal intubation through an SGA impossible. Additional limitations exist regarding removal of the SGA and maneuverability of the flexible bronchoscope.

RéSUMé: CONTEXTE: L'intubation endotrachéale guidée par bronchoscope flexible via un dispositif supraglottique (DSG) est un élément établi des algorithmes utilisés pour les intubations difficiles. La réussite de l'intubation peut être limitée par des incompatibilités dimensionnelles entre les tubes endotrachéaux (TET) et les DSG. MéTHODE: Dans cette étude in vitro, nous avons testé la faisabilité de faire passer un TET par un DSG, le retrait du DSG par-dessus le TET et la possibilité de guider un bronchoscope flexible avec 13 marques de TET (diamètre interne, 6,5-8,0 mm) et dix DSG différents (#4 et #5) sur un mannequin d'intubation. RéSULTATS: Nous avons testé 1040 combinaisons de DSG et de TET. Le passage du tube endotrachéal a échoué dans 155 (30 %) combinaisons avec les cinq DSG de première génération testés (117 [46 %] avec DSG #4, 38 [15 %] avec DSG #5) et dans trois (0,6 %) combinaisons avec les cinq DSG de deuxième génération testés (deux [0,8 %] avec DSG #4 et une [0,4 %] avec DSG #5). La raison de l'échec du passage d'un TET à travers un DSG de première génération était systématiquement liée à un connecteur de DSG trop étroit. Dans les 882 combinaisons restantes, le retrait du DSG par-dessus le TET s'est avéré impossible avec toutes les tailles de TET armés, à l'exception du TET armé Parker, et était possible avec tous les TET non armés. Une seule combinaison avec le DSG #4 et 84 combinaisons avec le DSG #5 n'étaient pas idéales pour guider le bronchoscope flexible de manière adéquate. CONCLUSION: Les combinaisons cliniquement pertinentes de TET et de DSG de tailles adultes peuvent être incompatibles, rendant impossible l'intubation endotrachéale guidée par bronchoscope flexible via un DSG. D'autres limites existent en ce qui concerne le retrait du DSG et la maniabilité du bronchoscope flexible.

Successful endotracheal intubation using i-gel supraglottic airway device and ultrasonography in a patient with bedside cervical traction: A case report.

We report a case of successful endotracheal intubation using i-gel and ultrasonography without a laryngoscope in a patient with a bedside cervical traction device. A 57-year-old man was referred to the emergency department because of quadriparesis following a motor vehicle accident, who was confirmed to have cervical dislocation with spinal cord compression. For ventilation support, the i-gel rescue airway device was placed to secure the patient airway temporarily. Then, an endotracheal tube was passed through the stem of the i-gel while observing the optimal tube position with ultrasonography. This case showed that ultrasonography can be used for early confirmation of endotracheal tube placement into the trachea via the i-gel.