Conduit For Tracheal Intubation Research Articles

Comparing Ambu AuraGain™ Disposable Laryngeal Mask with i-gel™ as a conduit for fibreoptic guided tracheal intubation for elective surgery under general anaesthesia in adult patients

BackgroundSupraglottic airway devices (SADs) have emerged as an alternative for airway management, serving as conduits for tracheal intubation with fibreoptic bronchoscopy (FOB). In this study, we aim to compare the efficacy of two SADs for FOB guided tracheal intubation in adult patients undergoing elective surgery. Methods120 patients were randomly assigned to two groups Group A (i-gel™) or Group B (Ambu AuraGain™ Disposable Laryngeal Mask). The ease of insertion, time for successful placement, number of attempts, need for manipulation, time for FOB intubation and laryngeal view were recorded. ResultsThe first pass success rate of intubation through either SAD was 100% (p = 1). Group A had a significantly higher ease of insertion score of 1 than Group B (63.33% vs 38.33%, p = 0.003). The time required for successful placement of the device was significantly longer in Group B than in Group A (17.44 ± 5.46 s vs13.62 ± 4.67 s, p = 0.001). The mean ± SD of time for FOB guided intubation(seconds) in group A was 66.59 ± 21.42 which was significantly higher as compared to group B (55.93 ± 19.79) (p value = 0.005). Conclusion: Our study compared i-gel™ and Ambu AuraGain™ for FOB-guided tracheal intubation and found both SADs equally effective with similar laryngeal views. Despite i-gel's superior ease of insertion, shorter time for insertion and fewer airway manipulations for insertion, Ambu AuraGain™ exhibited a shorter intubation time. Incidences of intraoperative and postoperative complications were comparable. Clinicians should choose the SAD based on preference and familiarity.

A Comparison of Tracheal Intubation with Ambu® AuraGainTM, Fastrach® and BlockBuster® Laryngeal Mask Airway: A Randomised Clinical Trial

Introduction: Airway management has been a key to quality, efficacy and safety of anaesthesia. The Ambu® AuraGain™ is an anatomically curved Supraglottic Airway Device (SAD), which has gastric access port and is used for both ventilation and endotracheal intubation. Fastrach® Intubating Laryngeal Mask Airway (FT-LMA) serves as a conduit for intubation and ventilation for difficult airway situation. It has an epiglottic elevating bar designed to lift the epiglottis as endotracheal tube passes. BlockBuster® LMA is latest generation LMA used for ventilation and intubation. It has a short airway tube which has > 95° angulation to match the oropharyngeal curve and thus makes the insertion easy and less traumatic. Aim: To compare first attempt success rate of tracheal intubation using Ambu® AuraGain™, Fastrach® and BlockBuster® LMA in adult patients. Materials and Methods: The present randomised clinical trial was conducted in the Department of Anaesthesiology, Ravindra Nath Tagore Medical College, Udaipur, Rajasthan, India from February 2021 to February 2022. The study comprised of 135 ASA physical status I and II patients of both sex, aged 18-60 years who were admitted and scheduled for elective surgery requiring general anaesthesia and tracheal intubation. The patients were randomly assigned into three groups (45 in each) - group A (Ambu® AuraGain™ group), group F (Fastrach® group), and group B (BlockBuster® group). Tracheal intubation was performed using appropriate size endotracheal tube after LMA placement. The outcome measures were first attempt successful intubation, time taken for intubation, glottis visualisation, and incidence of complications (blood stained LMA, nausea/vomiting). Results: The mean age of the group A, group B and group F were 35.8±15.0, 32.71±12.59, and 38.7.0±14 respectively which was statistically not significant. Group B had a significantly greater success rate of first attempt intubation (93.3%) in comparison with group F (64.4%), and group A (22.2%). LMA insertion score of 1 was found in 53.3% patients in group B, 42.2% patients in group F and 15.5% patients in group A. A Brimacombe score of 4 was found in 46.6% patients in group B as compared to 13.3% patients in group F and (33.3%) patients in group A, (p-value=0.020). Blood stained LMA was found in 1 patient in group B, 9 in group F and 7 in group A (p-value=0.030). Conclusion: BlockBuster® LMA is a better conduit for tracheal intubation than Fastrach® LMA and Ambu® AuraGain™ in adult patients with no anticipated airway difficulties.

Intubating Through Supraglottic Airway Devices: A Narrative Review

Implication Statement: Despite the increasing popularity of video laryngoscopes, the supraglottic airway device (SAD) remains a critical airway rescue tool. The SAD provides a conduit for tracheal intubation in failed laryngoscopy. This article aims to help the operator: (1) select an intubating SAD with consistent performance; (2) inform the appropriate SAD-endotracheal tube pairings; and (3) explain various SAD and endotracheal tube maneuvers available to increase chances of successful intubation. Objectives: The first supraglottic airway device (SAD) was introduced more than thirty years ago. Since then, SADs have undergone multiple iterations and improvements. The SAD remains an airway rescue device for ventilation and an intubation conduit on difficult airway algorithms. Data Sources: Several SADs are specifically designed to facilitate tracheal intubation, i.e., “intubating SADs,” while most are “non-intubating SADs.” The two most commonly reported tracheal intubation methods via the SADs are the blind and visualized passage of the endotracheal tube (ETT) preloaded on a fiberoptic scope. Fiberoptic guided tracheal intubation (FOI) via an intubating SAD generally has higher success rates than blind intubations and is thus preferred. However, fiberscopes might not always be readily available, and anesthesiologists should be skilled to successfully intubate blindly through a SAD. Summery: This narrative review describes intubating SAD with consistent performance, appropriate SAD-ETT pairings, and various SAD and ETT maneuvers to increase successful intubation chances.

A randomized trial comparing the Ambu® Aura-i™ and the Ambu® Aura Gain™ laryngeal mask as conduit for tracheal intubation in children.

The Ambu Aura Gain is a newer second-generation supraglottic airway device designed for fibreoptic bronchoscopy (FOB)-guided tracheal intubation. 57 patients between 18 months and six years of age were randomized to receive either the Ambu Aura-I (N.=29) or the Ambu Aura Gain (N.=28). Primary endpoint was the time for intubation. Secondary endpoints were the time and number of attempts for device insertion, the feasibility of FOB-guided intubation, the oropharyngeal leak pressure (OLP) the fibreoptic grade of laryngeal view and possible complications. No difference was found in the time for intubation, the time for device insertion or the fibreoptic grade of laryngeal view. First-attempt device insertion was successful in all (N.=28) patients with Aura Gain (100%) and in 27 (97%) with Aura-i. In the Aura-i group one insertion failed. A significant difference in successful intubation was seen between the Aura-i and the Aura Gain (79% vs. 100%, respectively, P=0.0011). Also found was a significant difference in the mean OLP (SD) between the Ambu Aura-i and the Ambu Aura Gain (18 [3] vs. 20 [3] cmH<inf>2</inf>O, respectively; mean difference [MD] 2 cmH<inf>2</inf>O; P=0.005). The Ambu Aura Gain served as a reliable device for FOB-guided tracheal intubation. Even if the time for intubation, when intubation was possible did not differ, the Aura-i showed only 79% intubation success, making it a doubtful device for FOB-guided tracheal intubation in cases of emergency and severe hypoxemia in small children.

Clinical evaluation of Ambu® Aura-i™ - A new intubating laryngeal mask airway as an independent ventilatory device and a conduit for tracheal intubation in pediatric patients.

Background:Ambu® Aura-i™, a recently introduced second generation supraglottic airway device has been designed to function as an independent ventilatory device as well as a conduit for passage of conventional cuffed tracheal tubes through it. There is dearth of literature on experience of tracheal intubation through intubating laryngeal mask airway (ILMA) in paediatric age group. This study was conducted to study the ventilatory effectiveness and the intubating characteristics of Ambu® Aura-i™ in paediatric patients.Aim:To study the effectiveness of Ambu ® Aura-i ™ as a supraglottic device for its ventilatory effectiveness and intubation characteristics in paediatric patients.Objectives:To study the Ventilatory effectiveness of Ambu ® Aura-i ™ in terms of: 1) Time taken in insertion of Ambu ® Aura-i ™. 2) No of attempts made for successful insertion of Ambu ® Aura-i™. 3) Tidal volume attained on positive pressure ventilation. 4) Etco2, Spo2 and Leak pressure achieved. To study the Intubating characterstics of Ambu ® Aura-i ™ in terms of :- 1) Grade of alignment of the ventilating orifice achieved in relation to the larynx in the fibre optic view. 2) Time taken in intubation through Ambu ® Aura-i ™. 3) Number of attempts made in intubation. 4) Time taken for removal of the Ambu ® Aura-i ™ after intubation through it has been accomplished.Method:Sixty three children undergoing elective surgery under general anaesthesia requiring intubation of trachea, weighing between 5-30 kg were stratified into 3 groups (n= 21) each. Ambu® Aura-i™ size 1.5 , 2.0 ,2.5 were used based on their body weight for airway management. Ventilatory effectiveness was studied in terms of success rate, number of attempts made at insertion, time taken in insertion, tidal volume delivered and leak pressure achieved. Intubating characterstics studied during fibreoptic guided tracheal intubation included grade of alignment of the ventilating orifice achieved in relation to the larynx in fibre optic view, time taken in fibreoptic guided tracheal intubation, success rate and number of attempts made at intubation. Time taken in removal of the device and complications observed were also recorded.Results:Ambu® Aura-i™ insertion, fibreoptic guided tracheal intubation and device removal were successful in all the patients in first attempt. The mean time taken in successful device insertion was 10.83±2.04 sec. The mean tidal volume delivered was 7.88±1.33 ml/kg body weight and mean leak pressure achieved was 16.27±5.2 cm H2O. The fibreoptic guided intubation was possible in first attempt in 100% of the patients (n=63). The Fibre optic view was grade 1 in 82.55% patients (n=52 /63) and grade 2 in 17.46% (n=11/ 63) patients. The mean time taken in fibre optic guided intubation was 12.68 ±2.82 sec. The mean time taken in removal of the device over the tracheal tube was 12.27 sec. There was no significant incidence of trauma to soft tissues, sore throat, laryngospasm or hoarseness of voice.Conclusion:On the basis of observations of this study, we conclude that Ambu ® Aura-i ™ is not only an effective ventilatoy device, but also an excellent conduit for fibre optic guided intubation using conventional uncuffed endotracheal tube in paediatric patients. Ambu ® Aura-i ™ , is also valuable for establishing rapid airway access in emergent difficult paediatric airway.

Blind Tracheal Intubation through the Air-Q Intubating Laryngeal Airway in Pediatric Patients: Reevaluation - A Randomized Controlled Trial.

Context:Some pediatric supraglottic airway devices have not been evaluated in a large perspective for blind intubation although they are validated as a conduit for fiberoptic-guided intubation.Objective:The objective of this study was to compare the success rate of blind technique with correction maneuvers versus fiberoptic-guided intubation through the air-Q laryngeal airway in pediatric patients.Patients and Methods:One hundred and twenty-six pediatric patients undergoing elective surgery under general anesthesia were randomized into two equal groups. The air-Q was placed in all patients as a conduit for tracheal intubation. Group B patients underwent blind intubation with correction maneuvers. Group F patients underwent fiberoptic-guided intubation.Results:There was no significant difference between the groups regarding the success rate of intubation or postextubation complications. Group F patients showed a significantly longer time to intubation and total time of the trial. Furthermore, Group F patients showed a significantly higher level of pre- and postintubation heart rate compared to Group B patients.Conclusion:Blind tracheal intubation in pediatric patients through the air-Q with correction maneuvers could be a good alternative for fiberoptic-guided intubation with stable hemodynamics and shorter time till intubation.

I-Gel versus laryngeal mask airway (LMA) classic as a conduit for tracheal intubation using ventilating bougie.

Background and Aims:Supraglottic airways (SGAs) are generally used for airway management; but can also be used as a conduit for tracheal intubation. Our primary aim was to evaluate i-Gel and laryngeal mask airway (LMA) classic as conduits for tracheal intubation using ventilating bougie by assessing number of attempts and time for insertion of SGAs, ventilating bougie and endotracheal tube (ETT), and total intubation time.Material and Methods:A randomized clinical trial was carried out in 58 patients requiring general anesthesia and endotracheal intubation for planned surgery. They were randomly divided into Group I and Group C. After induction of anesthesia, i-Gel was inserted in Group I and LMA Classic in Group C; ventilating bougie was passed through SGA followed by the removal of SGA and railroading of ETT over ventilating bougie. Parameters observed were number of attempts and time taken for device insertion, total intubation time, and hemodynamic variables.Results:Twenty-nine patients were included in each group. First attempt success rate for SGA insertion (86.2% in Group I and 75.9% in Group C (P = 0.5)), ventilating bougie insertion (79.32% in Group I and 82.8% in Group C (P = 0.99)) and ETT insertion (100% in Group I and 96.5% in Group C) was not different in the two groups. Total intubation time was 93.3 ± 9.0 s in Group I and 108. 96 ± 16.5 s in Group C (P < 0.0001).Conclusions:i-Gel and LMA Classic both can be used as a conduit for tracheal intubation using ventilating bougie with stable hemodynamic parameters.

Comparison of Endotracheal Intubation Through I-gel and Intubating Laryngeal Mask Airway

Background: Supraglottic airway devices (SADs) are very useful airway adjunct in managing anticipated and unanticipated difficult airway and can be used as a ventilating aid and as a conduit for tracheal intubation. The new versions of SADs like i-gel and intubating laryngeal mask airway (ILMA), have advantage of hands-free airway maintenance without the need for tracheal intubation, they can be placed easily without direct visualization of the larynx, ensure predictable ventilation and can be used as conduit for tracheal intubation. Objective: To compare ease and success of placement of both SADs and ease and success of endotracheal (ET) intubation through both SADs. Method: Eighty patients of both sexes, aged between 18-60 years and belonging to ASA grade I and II undergoing surgical procedure under general anaesthesia (GA) were randomly divided into two group (i-gel and ILMA) of equal number. Following induction the allocated device was inserted and after confirming adequate ventilation, blind ET intubation was attempted through the device. First attempt and overall success rate of SAD insertion and ET intubation through SAD; time taken for SAD insertion and ET intubation through SAD; hemodynamic changes and postoperative complications were recorded and compared between groups. Result: Demographic profile, success rate of SAD insertion, haemodynamic changes and adverse effects were similar between groups (p&gt;0.05).Overall time needed for successful SAD insertion was significantly shorter in group i-gel (22.52±5.64 sec) than group ILMA (31.15±5.52 sec) (p value &lt;0.0001). Overall success rate of blind ET intubation was higher in group i-gel (75%) in comparison to group ILMA (65%). I-gel required significantly less time to achieve successful ET intubation than ILMA (26.30±11.35 sec vs. 33.53±13.13 sec)(p&lt;0.0001). Conclusion: Both the SADs were proved to be useful alternative to conventional laryngoscope for ET intubation, although i-gel required lesser time and had better success rate of ET intubation as compared to ILMA.

Blind intubation of anaesthetised children with supraglottic airway devices AmbuAura-i and Air-Q cannot be recommended: A randomised controlled trial.

Paediatric supraglottic airway devices AmbuAura-i and Air-Q were designed as conduits for tracheal intubation. Although fibreoptic-guided intubation has proved successful, blind intubation as a rescue technique has never been evaluated. Evaluation of blind intubation through AmbuAura-i and Air-Q. On the basis of fibreoptic view data, we hypothesised that the success rate with the AmbuAura-i would be higher than with the Air-Q. A randomised controlled trial. University Childrens' Hospital; September 2012 to July 2014. Eighty children, American Society of Anesthesiologists (ASA) class I to III, weight 5 to 50 kg. Tracheal intubation was performed through the randomised device with the tip of a fibrescope placed inside and proximal to the tip of the tracheal tube. This permitted sight of tube advancement, but without fibreoptic guidance (visualised blind intubation). Primary outcome was successfully visualised blind intubation; secondary outcomes included supraglottic airway device success, insertion times, airway leak pressure, fibreoptic view and adverse events. Personal data did not differ between groups. In contrast to our hypothesis, blind intubation was possible in 15% with the Air-Q and in 3% with the AmbuAura-i [95% confidence interval (95% CI) 6 to 31 vs. 0 to 13%; P = 0.057]. First attempt supraglottic airway device insertion success rates were 95% (Air-Q) and 100% (AmbuAura-i; 95% CI 83 to 99 vs. 91 to 100; P = 0.49). Median leak pressures were 18 cmH2O (Air-Q) and 17 cmH2O [AmbuAura-i; interquartile range (IQR) 14 to 18 vs. 14 to 19 cmH2O; P = 0.66]. Air-Q insertion was slower (27 vs. 19 s, P < 0.001). There was no difference in fibreoptic view, or adverse events (P > 0.05). In one child (Air-Q size 1.5, tube size 3.5), the tube dislocated during device removal. Ventilation with both devices is reliable, but success of blind intubation is unacceptably low and cannot be recommended for elective or rescue purposes. If intubation through a paediatric supraglottic airway device is desired, we suggest that fibreoptic guidance is used. Clinicaltrials.gov identifier: NCT01692522.

Distance from the glottis to the grille

Supraglottic airway devices are often used in airway management to facilitate tracheal intubation. Knowledge of the distance from the grille of the device to the patient's vocal cords is essential for the safe passage of the tracheal tube below the vocal cords. To assess the distance from the glottis to the grille of three supraglottic airway devices [LMA (LMA Unique), Air-Q (Air-Q Intubating Laryngeal Airway Reusable) and CobraPLA (Cobra Perilaryngeal Airway)] and their safe usage as intubation conduits. Randomised controlled trial. Tertiary, university hospital. Thirty women undergoing elective gynaecological surgery with planned supraglottic airway management. In-vivo fibreoptic assessment and in-vitro measurement. The distance from the grille to the glottis was defined as primary outcome. The distance from the beginning of the cuff of a tracheal tube passed through the device to the grille was assessed as secondary outcome. The three devices exhibited significant differences in the mean ± SD distance from the glottis to the grille (LMA 4.6 ± 1.5 cm, Air-Q 5.7 ± 1.4 cm, CobraPLA 3.4 ± 1.4 cm; P = 0.009). The Air-Q was predicted to allow the safe passage of a tracheal tube into the trachea, whereas the cuff was predicted to rest on the vocal cords in 57% of the LMA patients and 14% of the CobraPLA patients. Using the LMA Unique as a conduit for tracheal intubation may pose a safety risk, whereas the use of the Air-Q would position the tracheal tube at a safe depth in the trachea.

Comparison of the air-Q intubating laryngeal airway and the cobra perilaryngeal airway as conduits for fiber optic-guided intubation in pediatric patients.

Background:One of the methods proposed in cases of difficult airway management in children is using a supraglottic airway device as a conduit for tracheal intubation. The aim of this study was to compare the efficacy of the Air-Q Intubating Laryngeal Airway (Air-Q) and the Cobra Perilaryngeal Airway (CobraPLA) to function as a conduit for fiber optic-guided tracheal intubation in pediatric patients.Materials and Methods:A total of 60 children with ages ranging from 1 to 6 years, undergoing elective surgery, were randomized to have their airway managed with either an Air-Q or CobraPLA. Outcomes recorded were the success rate, time and number of attempts required for fiber optic-guided intubation and the time required for device removal after intubation. We also recorded airway leak pressure (ALP), fiber optic grade of glottic view and occurrence of complications.Results:Both devices were successfully inserted in all patients. The intubation success rate was comparable with the Air-Q and the CobraPLA (96.7% vs. 90%), as was the first attempt success rate (90% vs. 80%). The intubation time was significantly longer with the CobraPLA (29.5 ± 10.9 s vs. 23.2 ± 9.8 s; P < 0.05), but the device removal time was comparable in the two groups. The CobraPLA showed a significantly higher ALP (20.8 ± 5.2 cmH2O vs. 16.3 ± 4.5 cmH2O; P < 0.001), but the fiber optic grade of glottic view was comparable with the two devices. The CobraPLA was associated with a significantly higher incidence of blood staining of the device on removal and post-operative sore throat.Conclusion:Both the Air-Q and CobraPLA can be used effectively as a conduit for fiber optic-guided tracheal intubation in children. However, the Air-Q proved to be superior due to a shorter intubation time and less airway morbidity compared with the CobraPLA.

Extraglottic airway devices: A review.

Extraglottic airway devices (EAD) have become an integral part of anesthetic care since their introduction into clinical practice 25 years ago and have been used safely hundreds of millions of times, worldwide. They are an important first option for difficult ventilation during both in-hospital and out-of-hospital difficult airway management and can be utilized as a conduit for tracheal intubation either blindly or assisted by another technology (fiberoptic endoscopy, lightwand). Thus, the EAD may be the most versatile single airway technique in the airway management toolbox. However, despite their utility, knowledge regarding specific devices and the supporting data for their use is of paramount importance to patient's safety. In this review, number of commercially available EADs are discussed and the reported benefits and potential pitfalls are highlighted.

The LMA Classic™ as a conduit for tracheal intubation in adult patients: a review and practical guide

AbstractUnexpected difficulty in maintaining an open airway following induction of anaesthesia remains an ever-present hazard. Repetitive attempts at direct laryngoscopy and intubation are generally acknowledged to be inappropriate. The LMA ClassicTM is recognised as a rescue ventilation device in failed intubation scenarios and its specific role is well defined in international airway management protocols. Should clinical conditions dictate the need for tracheal intubation following placement of an LMA ClassicTM, it may be retained to serve as a conduit for intubation. Utilising the LMA ClassicTM as a conduit for intubation is considered a rescue manoeuvre, only resorted to when conventional methods such as direct laryngoscopy have failed. Therefore, it is important that this approach to intubation has a high success rate and that airway management specialists are familiar with the different available options, the relevant limitations and the pitfalls. A short description of the components of the LMA Cla...

Airway management evolution - in a search for an ideal extraglottic airway device.

Extraglottic airway devices (EADs) are commonly used equipment for airway maintenance during elective procedures under general anaesthesia. They may be used also in other indications such as conduit for tracheal intubation or rescue airway device in prehospital medicine. Current classifications of the EADs lack systematic approach and therefore classification according to the sealing sites and sealing mechanisms is suggested in this review article. Modern EADs are disposable, latex-free devices made of plastic materials most commonly from polyvinylchloride (PVC). The bowl of uncuffed sealers is manufactured from different materials such as thermoplastic elastomers or ethylene-vinyl-acetate co-polymer. EADs create various physical forces exerted on the adjacent tissues which may contribute to different sealing characteristic of particular device or to variable incidence of postoperative complications. Desired features of an ideal EAD involve easy insertion, high insertion success rate even by inexperienced users, protection against aspiration of gastric contents and low incidence of postoperative complications such as sore throat, hoarseness, cough or swallowing difficulties.

Prone insertion of a size 0.5 intubating laryngeal airway overcomes severe upper airway obstruction in an awake neonate with Pierre Robin syndrome

To the Editor, We present a case of a one-day-old 3-kg neonate who was scheduled to undergo a computed tomography (CT) scan to examine a severe upper airway obstruction secondary to Pierre Robin syndrome. The patient had remained in a prone position in the neonatal intensive care unit since birth, as transition to the supine position resulted in severe upper airway obstruction, sternal retractions, and oxygen desaturations despite the use of a nasopharyngeal airway. Commonly described goals to manage the airway in this context include using an oral/nasal airway to alleviate the airway obstruction prior to induction of anesthesia, using a supraglottic airway device, 1 and possibly securing the airway with a tracheal tube using a fibreoptic bronchoscope through a supraglottic device. We have experienced favourable results using the intubating laryngeal airway (ILA TM ) (Cookgas LLC; St Louis, MO, USA) as a conduit for tracheal intubation in neonates and infants with a difficult airway. 2,3 As the patient was unable to tolerate the supine position, airway management was performed in the CT suite with the patient awake in the prone position without administration of anesthetic agents. The anesthetic considerations for this patient included obtaining intravenous access, administration of an antisialagogue and chronotropic agent, and management of the airway with the patient in the awake state. Our primary plan was to place the ILA to manage the airway with the patient in the awake state, and our back-up plan was to intubate the trachea through the ILA using a fibreoptic bronchoscope. We applied standard American Society of Anesthesiologists’ monitors, and the anesthesia machine was then checked. Next, intravenous access was established in the patient’s left foot with the child awake prior to any airway intervention. Atropine 0.1 mg was subsequently administered as an antisialagogue. An assistant extended and stabilized the neonate’s head over the edge of the bed, and a size 0.5 ILA was placed with minimal gagging. The patient was then turned to the supine position with resultant improvement in airway

Use of intubation introducers through a supraglottic airway to facilitate tracheal intubation: a brief review

This article is a narrative review regarding the usage and effectiveness of introducers or catheters to facilitate tracheal intubation through a supraglottic airway (SGA) as an alternative intubation technique in normal and difficult airway management. Relevant articles were obtained through Medline (1948-July 2011). The articles were subsequently cross-referenced for additional literature, and only articles published in English were included. In this review, we consider 32 reports using the LMA Classic™, LMA Unique™, LMA ProSeal™, LMA Supreme™, AuraOnce™, and i-gel™ as SGA conduits for intubation. In 13 articles, the use of an Aintree Intubation Catheter was described as an intubation introducer and resulted in high success rates in both elective and emergent situations. Eight studies used a guidewire exchange catheter technique. Although blind intubation using a guidewire resulted in a high failure rate, these studies found that using a bronchoscope improved successful intubation. Ten studies showed that insertion of a gum elastic bougie with a bronchoscope as an intubation introducer has high success rates compared with blind bougie insertion. One article described the use of a small endotracheal tube as an intermediary for tracheal intubation. In failed intubation scenarios, supraglottic airways, such as the LMA Classic™ or LMA ProSeal™ can serve as a conduit for tracheal intubation. A number of techniques using introducers or catheters can facilitate the insertion of an adequately sized endotracheal tube, particularly guided by a bronchoscope. Usage of introducers or catheters through a supraglottic airway may be a useful alternative intubation technique in difficult airway management.

Brief review: The LMA Supreme™ supraglottic airway

This article is a review of the efficacy and safety of the Laryngeal Mask Airway (LMA) Supreme™ as a stand-alone supraglottic airway during general anesthesia and as a conduit for tracheal intubation. Relevant articles were obtained using MEDLINE (1948-July 2011) and EMBASE (1980-July 2011). Only original studies with adult human patients and published in English were selected. The LMA Supreme was found to be comparable with the LMA Proseal™ with regard to success rate, insertion time, and complications. However, in three studies, oropharyngeal leak pressure was higher with the LMA Proseal than with the LMA Supreme. The LMA Supreme was superior to the LMA Classic™ with regard to insertion time and oropharyngeal seal pressure. The LMA Supreme was also used successfully in two difficult airway cases, and it has been used as a conduit for tracheal intubation by utilizing an intubation introducer (gum elastic bougie) and subsequently railroading an endotracheal tube over the bougie into the trachea. Techniques for achieving tracheal intubation include the use of the Aintree Intubation Catheter®, a guidewire-exchange catheter, a gum elastic bougie, and a small (<6.0mm internal diameter) endotracheal tube. The LMA Supreme has been shown to be a safe and efficacious device as a stand-alone supraglottic airway and may also be used as a conduit for tracheal intubation. Further trials are needed to determine the efficacy of the LMA Supreme compared with other supraglottic airways in both elective and emergent airway management situations.

Tracheal intubation in an unanticipated difficult airway by advancing a bronchoscope and a tracheal tube introducer through a LMA Supreme™

To the Editor, We report a case involving a patient with an unanticipated difficult airway in whom tracheal intubation was achieved uneventfully by advancing a bronchoscope and a tracheal tube introducer through a LMA Supreme. The patient’s written consent was obtained for this publication. A 70 kg, 52-yr-old woman was scheduled for nephrolithotomy. She had an adequate mouth opening, a normal thyromental distance, and a Mallampati class 3 airway. Anesthesia was induced with midazolam, fentanyl, propofol, and atracurium iv. Adequate mask ventilation was achieved. Direct laryngoscopy with a Macintosh #3 blade showed a Cormack-Lehane Grade 3 laryngeal view and tracheal intubation failed in two attempts. After further mask ventilation, oral bronchoscopic (5.0 mm outer diameter [OD]) intubation was attempted but failed due to poor visualization from blood and secretions. The SPO2 decreased to 90%. A size 4 LMA Supreme (LMA International, Singapore) was inserted with a satisfactory capnographic waveform and SPO2 returned to 100%. A decision was then made to intubate the patient’s trachea via the LMA Supreme. A pediatric bronchoscope (Olympus BF XP60, 2.8 mm OD) operated by an anesthesiologist and a solid tracheal tube introducer with a coude tip (5 mm OD, Well Lead Medical, China) operated by a second anesthesiologist were advanced through the airway lumen of the LMA Supreme into the pharynx (Figure). The tracheal tube introducer was advanced under bronchoscopic guidance through the glottis into the trachea and positioned 3 cm above the carina. The bronchoscope and LMA Supreme were then removed while keeping the tracheal tube introducer in position. A 7.0 mm internal diameter (ID) tracheal tube was railroaded over the tracheal tube introducer and into the trachea, and positioning of the tracheal tube was confirmed by capnography. Ten minutes after the completion of surgery, the patient was awakened and the tracheal tube was removed. The patient’s recovery was uneventful. After failed attempts at tracheal intubation, a supraglottic airway may be inserted for lung ventilation while awaiting alternative airway equipment. In lieu of removing the supraglottic airway to attempt alternative intubation techniques, it can be kept in situ as a conduit for tracheal intubation. Ventilation is not interrupted and secretions and blood are kept posterior to the supraglottic airway allowing a clear path to the larynx. The LMA Supreme is a single-use variant of the LMA Proseal. Its curved shaft consists of a double lumen, i.e., a central lumen for gastric access within an airway lumen for respiratory tract access. Like the LMA Classic, it is difficult to pass an adequately sized endotracheal tube (ETT) directly through the LMA Supreme due to the airway luminal diameter. There are four techniques to achieve tracheal intubation with an adequately sized ETT, through the use of introducers or catheters, via the LMA Supreme. The four techniques utilize a small ETT, an Aintree Intubating Catheter, a guidewire, or a tracheal tube introducer. With the first technique, a small ETT (up to 6.0 mm ID) is mounted over a bronchoscope and inserted into the trachea through the LMA Supreme. Subsequently, an airway exchange catheter is inserted via the ETT, which is later exchanged for a full-sized ETT. Q.-J. Chu, MD X.-P. Han, MD First Affiliated Hospital, Zhengzhou University, Zhengzhou, China

Supraglottic airways in difficult airway management: successes, failures, use and misuse

Supraglottic airway devices (SAD) play an important role in the management of patients with difficult airways. Unlike other alternatives to standard tracheal intubation, e.g. videolaryngoscopy or intubation stylets, they enable ventilation even in patients with difficult facemask ventilation and simultaneous use as a conduit for tracheal intubation. Insertion is usually atraumatic, their use is familiar from elective anaesthesia, and compared with tracheal intubation is easier to learn for users with limited experienced in airway management. Use of SADs during difficult airway management is widely recommended in many guidelines for the operating room and in the pre-hospital setting. Despite numerous studies comparing different SADs in manikins, there are few randomised controlled trials comparing different SADs in patients with difficult airways. Therefore, most safety data come from extended use rather than high quality evidence and claims of efficacy and particularly safety must be interpreted cautiously.

Evaluation of air‐QTM intubating laryngeal airway as a conduit for tracheal intubation in infants – a pilot study

Air-Q™ intubating laryngeal airway (ILA) has been used successfully as a conduit for tracheal intubation in pediatric difficult airway. However, its use as an airway device and conduit for intubation in infants is not yet evaluated. The primary objective was to evaluate ILA as a conduit for tracheal intubation in infants, and secondary objectives were to evaluate ILA in terms of ease of insertion and ventilation, oropharyngeal leak pressure (OLP), glottic view, and complications. Twenty infants with normal airway were included. After induction of general anesthesia and neuromuscular blockade, ILA (size 1.0/1.5) was inserted. Fiberoptic bronchoscope (FOB)-guided intubation and removal of ILA with the stabilizing stylet was attempted. The mean age and weight of the infants were 7.5 ± 2.3 months and 7.3 ± 1.8 kg. The ILA sizes 1.0 and 1.5 were inserted in 10 infants each according to the weight of the infants. The mean OLP was 18.5 ± 1.8 cm H₂O, and mean time for insertion of ILA was 13.3 ± 3.9 s. Glottic view was grade I in 6, grade II in 1, grade III in 4, and grade IV in nine infants. Tracheal intubation was successful in 19/20 infants. The mean endotracheal tube (ETT) insertion time and mean total time (ILA insertion to the confirmation of ETT placement) were 95.6 ± 32.3 s and 306.42 ± 120.2 s respectively. The ILA is a safe and easy-to-use supraglottic airway device for intubation with FOB in infants with normal airway. Insertion and removal of ILA are easy with satisfactory oropharyngeal seal and ventilation.