i-gel™ supraglottic airway in clinical practice: a prospective observational multicentre study

Comparison of the effects of paratracheal pressure and cricoid pressure on placement of the i-gel® supraglottic airway: a randomized clinical trial

PURPOSE

Anesthesiologists can use supraglottic airway devices as a rescue technique for failed intubation even in patients with an increased risk of gastric regurgitation. In this randomized study, we aimed to evaluate the effects of cricoid pressure and paratracheal pressure on placement of the i-gel® (Intersurgical Ltd., Wokingham, Berkshire, UK).

METHODS

After induction of anesthesia in 76 adult patients, we inserted the i-gel under paratracheal or cricoid pressure, and assessed the success rate of i-gel insertion, resistance during insertion, time required for insertion, accuracy of the insertion location, tidal volumes, and peak inspiratory pressure with or without each maneuver after i-gel insertion.

RESULTS

The overall success rate of insertion was significantly higher under paratracheal pressure than under cricoid pressure (36/38 [95%] vs 27/38 [71%], respectively; difference, 24%; 95% confidence interval [CI], 8 to 40; P = 0.006]. Resistance during insertion was significantly lower under paratracheal pressure than under cricoid pressure (P < 0.001). The time required for insertion was significantly shorter under paratracheal pressure than under cricoid pressure (median [interquartile range], 18 [15-23] sec vs 28 [22-38] sec, respectively; difference in medians, -10; 95% CI, -18 to -4; P < 0.001). Fibreoptic examination of the anatomical alignment of the i-gel in the larynx revealed no significant difference in the accuracy of the insertion location between the two maneuvers (P = 0.31). The differences in tidal volume and peak inspiratory pressure with or without the maneuvers were significantly lower with paratracheal pressure than with cricoid pressure (P = 0.003, respectively).

CONCLUSIONS

Insertion of the i-gel supraglottic airway was significantly more successful, easier, and faster while applying paratracheal pressure than cricoid pressure.

STUDY REGISTRATION

ClinicalTrials.gov (NCT05377346); first submitted 11 May 2022.

Gastric distension and atelectasis after using a supraglottic airway - A case report

BACKGROUND

Supraglottic airways (SGAs) are used during general anesthesia (GA) due to comfort. Certain complications are possible, such as gastric distension. The incidence of pulmonary aspiration of regurgitated gastric contents was found to be 0.02%. A difference in the incidence of gastric regurgitation was not identified between the use of SGAs and endotracheal intubation. We report a case of gastric distension and atelectasis in a patient in whom an I-gel® was used for GA.

CASE

A 63-year-old female patient underwent triple arthrodesis on her ankle under GA using an SGA (I-gel® size 3). After surgery, she suffered from nausea and abdominal bloating. A chest radiograph revealed that a large amount of air in her stomach had caused gastric distention, which resulted in left hemidiaphragm elevation and atelectasis.

CONCLUSIONS

This case illustrates that the use of I-gel® in prolonged surgeries may result in malposition of the SGA and gastric insufflation and atelectasis.

Negative pressure pulmonary edema after general anesthesia using the i-gel

Negative pressure pulmonary edema (NPPE) is a rare complication that occurs mainly after tracheal extubation. We report a case of postoperative NPPE associated with the use of the i-gel. A 28-year-old woman was scheduled for an emergency right axillary sentinel lymph node excision. During emergence, the patient experienced a sudden onset of airway obstruction, and spontaneous ventilation through the i-gel was impossible. Pink and frothy secretions were noted in the i-gel and the patient's oral cavity. Positive airway pressure with 100% oxygen was applied using a facemask, and the patient was subsequently treated with high-flow oxygen therapy. In this case, laryngospasm or displacement of the i-gel was believed to be the cause of airway obstruction. We recognized that NPPE is likely to occur regardless of the airway device, and the use of the i-gel cannot completely eliminate the possibility of NPPE occurrence.

Transient Hypoglossal and Lingual Nerve Injury Following the Use of I-gel Supraglottic Airway: A Case Report

Injury to the hypoglossal and/or lingual nerve is a rare occurrence with the use of a laryngeal mask airway (LMA) or supraglottic airway (SGA) device. There has been one prior report of a lingual and hypoglossal nerve injury with the i-gel™ SGA. We are describing the second reported hypoglossal and lingual transient nerve injury in a male patient while using an i-gel™ SGA. Although excessive cuff pressure has been cited as a possible cause, the i-gel™ does not have a cuff. This report highlights that hypoglossal nerve injury can still occur, even with the use of a cuffless LMA such as the i-gel™ SGA.

Conventional versus reverse insertion of i-gel® in overweight and obese patients - Interventional randomised controlled trial

Background and Aims

The supraglottic airway device, i-gel, is used in obese patients for short- to medium-duration surgical procedures. Insertion techniques have contributed to the successful and proper placement of i-gel in the first attempt. This study aims to compare two techniques for successfully inserting i-gel in the first attempt in overweight and obese patients as measured by oropharyngeal leak pressure (OLP).

Methods

This interventional, randomised, controlled study was conducted after ethical approval, and trial registration in overweight and obese patients. Patients were randomised into two groups: In Group C, the conventional technique was used, while in Group R, the reverse technique was used to insert i-gel. OLP, successful placement, required manipulations, time taken for insertion, number of attempts, and intraoperative and postoperative complications were studied. The collected data were analysed statistically.

Results

The mean OLP (30.46 ± 3.76 vs. 32.12 ± 3.10 mmHg, P = 0.018) and the mean time of insertion (16.42 ± 1.86 vs. 13.98 ± 1.97 s, P = 0.001) for conventional and reverse techniques, respectively, were statistically significant and favourable for Group R compared to Group C. Successful placement of i-gel at the first attempt, ease of insertion, number of attempts and all the manipulations except withdrawal and advancement were comparable in both the groups. No postoperative complications were noted.

Conclusion

The reverse technique significantly favoured the actual OLP values and the mean insertion time. Successful placement of i-gel at the first attempt was observed with both conventional and reverse techniques.

Learning curve of i-gel insertion in novices using a cumulative sum analysis

The i-gel, a popular second-generation supraglottic airway device, has been used in a variety of airway management situations, including as an alternative to tracheal intubation for general anesthesia, rescue in difficult airway settings, and out-of-hospital cardiac arrest resuscitation. We aimed to investigate the number of experiences needed to achieve a rapid, highly successful first attempt i-gel insertion in novices with a cumulative sum analysis. We also looked at how learning affected success rates, insertion time, and bleeding and reflex (limb movement, frowning face, or coughing) incidences. This prospective observational study included 15 novice residents from March 2017 to February 2018 in a tertiary teaching hospital. Finally, 13 residents with 35 [30-42] (median [interquartile range]) cases of i-gel insertion were analyzed. The cumulative sum analysis showed that 11 of 13 participants had an acceptable failure rate after 15 [8-20] cases. With increasing experience, success rate (P = 0.004), insertion time (P < 0.001), and incidence of bleeding (P = 0.006) all improved. However, the incidence of reflex did not change (P = 0.43). Based on our results, we suggest that 20 cases are preferable for novices to develop skills in using the i-gel in airway management.

A Retrospective Nationwide Comparison of the iGel and King Laryngeal Tube Supraglottic Airways for Out-of-Hospital Cardiac Arrest Resuscitation

INTRODUCTION

While various supraglottic airway devices are available for use during out-of-hospital cardiac arrest (OHCA) resuscitation, comparisons of patient outcomes by device are limited. In this study, we aimed to compare outcomes of OHCA patients who had airway management by emergency medical services (EMS) with the iGel or King-LT.

METHODS

We used the 2018-2021 ESO Data Collaborative public use research datasets for this retrospective study. All patients with non-traumatic OHCA who had iGels or King-LTs inserted by EMS were included. Our primary outcome was survival to discharge to home, and secondary outcomes included first-pass success, return of spontaneous circulation (ROSC), and prehospital rearrest. We examined the association between airway device and each outcome using two-level mixed effects logistic regression with EMS agency as the random effect, adjusted for standard Utstein variables and failed intubation prior to supraglottic airway insertion. Average treatment effects were calculated through propensity score matching.

RESULTS

A total of 286,192 OHCA patients were screened, resulting in 93,866 patients eligible for inclusion in this analysis. A total of 9,456 transported patients (59.8% iGel) had associated hospital disposition data. Use of the iGel was associated with greater survival to discharge to home (aOR:1.36 [1.06, 1.76]; ATE: 2.2%[+0.5, +3.8]; n = 7,576), first pass airway success (aOR:1.94 [1.79, 2.09]; n = 73,658), and ROSC (aOR:1.19 [1.13, 1.26]; n = 73,207) in comparison to airway management with the King-LT. iGel use was associated with lower odds of experiencing a rearrest (aOR:0.73 [0.67, 0.79]; n = 20,776). Among patients who received a supraglottic device as a primary airway, use of the iGel was not associated with significantly greater survival to discharge to home (aOR:1.26 [0.95, 1.68]). Among patients who received a supraglottic device as a rescue airway following failed intubation, use of the iGel was associated with greater odds of survival to discharge to home (aOR:2.16 [1.15, 4.04]).

CONCLUSION

In this dataset, use of the iGel during adult OHCA resuscitation was associated overall with better outcomes compared to use of the King-LT. Subgroup analyses suggested that use of the iGel was associated with greater odds of achieving the primary outcome than the King-LT when used as a rescue device but not when used as the primary airway management device.

Effect of Intermediate Airway Management on Ventilation Parameters in Simulated Pediatric Out-of-Hospital Cardiac Arrest: Protocol for a Multicenter, Randomized, Crossover Trial

Most pediatric out-of-hospital cardiac arrests (OHCAs) are caused by hypoxia, which is generally consecutive to respiratory failure. To restore oxygenation, prehospital providers usually first use basic airway management techniques, i.e., bag-valve-mask (BVM) devices. These devices present several drawbacks, most of which could be avoided using supraglottic airway devices. These intermediate airway management (IAM) devices also present significant advantages over tracheal intubation: they are associated with higher success and lower complication rates in the prehospital setting. There are, however, few data regarding the effect of early IAM in pediatric OHCA. This paper details the protocol of a trial designed to evaluate the impact of this airway management strategy on ventilation parameters through a simulated, multicenter, randomized, crossover trial. The hypothesis underlying this study protocol is that early IAM without prior BVM ventilations could improve the ventilation parameters in comparison with the standard approach, which consists in BVM ventilations only.

Comparison of the clinical performance of the i-gelTM, LMA SupremeTM, and Ambu AuraGainTM in adult patients during general anesthesia: a prospective and randomized study

BACKGROUND

Supraglottic airway devices (SADs) are routinely used for securing the airway. In this study, the clinical performance of three SADs in adult patients under general anesthesia was compared.

METHODS

American Society of Anesthesiologists physical status I-III subjects were randomly assigned to the i-gelTM (I), LMA SupremeTM (L), or Ambu AuraGainTM (A) group (30 per group). The primary objective of this study was to compare insertion times. Additionally, the ease of insertion, number of attempts, oropharyngeal leak pressure (OLP), airway maneuver requirement, difficulty with gastric tube placement, and complications were assessed.

RESULTS

Demographic data did not differ between the groups. Group I (16.9 ± 4.9 s) had a significantly shorter time of insertion than Group L (19.6 ± 5.2 s) and Group A (22.1 ± 5.7 s) (P = 0.001). The OLP for Group A (29.8 ± 3.0 cmH2O) was higher than those for Group L (24.1 ± 6.3 cmH2O) and Group I (9.4 ± 6.1 cmH2O) (P < 0.001). The number of insertion attempts (P = 0.232), ease of insertion (P = 0.630), airway maneuver requirement (P = 0.585), difficulty with gastric tube placement (P = 0.364), and complications (P = 0.873) were not significantly different between the groups.

CONCLUSIONS

All three devices are convenient and effective for airway management in adults under general anesthesia. However, the shorter insertion time required for the i-gel may make it more suitable for resuscitation and emergencies, while aspiration risk may be reduced with the Ambu AuraGain, given its high OLP.

The Importance of Acknowledging an Intermediate Category of Airway Management Devices in the Prehospital Setting

Prehospital airway devices are often classified as either basic or advanced, with this latter category including both supraglottic airway (SGA) devices and instruments designed to perform endotracheal intubation (ETI). Therefore, many authors analyze the impact of SGA and ETI devices jointly. There are however fundamental differences between these instruments. Indeed, adequate airway protection can only be achieved through ETI, and SGA devices all have relatively low leak pressures which might compromise both oxygenation and ventilation when lung compliance is decreased. In addition, there is increasing evidence that SGA devices reduce carotid blood flow in case of cardiac arrest. Nevertheless, SGA devices might be particularly useful in the prehospital setting where many providers are not experienced enough to safely perform ETI. Compared to basic airway management (bag-valve-mask) devices, SGA devices enable better oxygenation, decrease the odds of aspiration, and allow for more reliable capnometric measurement by virtue of their enhanced airtightness. For all these reasons, we strongly believe that SGA devices should be categorized as "intermediate airway management devices" and be systematically analyzed separately from devices designed to perform ETI.

Supraglottic airway device to improve ventilation success and reduce pulmonary aspiration during cardio-pulmonary resuscitation by basic life support rescuers: a randomised cross-over human cadaver study

Objectives: Early airway management during cardiopulmonary resuscitation (CPR) prevents aspiration of gastric contents. Endotracheal intubation is the gold standard to protect airways, but supraglottic airway devices (SGA) may provide some protection with less training. Bag-mask ventilation (BMV) is the most common method used by rescuers. We hypothesized that SGA use by first rescuers during CPR could increase ventilation success rate and also decrease intragastric pressure and pulmonary aspiration.Methods: We performed a randomized cross-over experimental trial on human cadavers. Protocol A: we assessed the rate of successful ventilation (chest rise), intragastric pressure, and CPR key time metrics. Protocol B: cadaver stomachs were randomized to be filled with 300 mL of either blue or green serum saline solution through a Foley catheter. Each rescuer was randomly assigned to use SGA or BMV during a 5-minute standard CPR period. Then, in a crossover design, the stomach was filled with the second colour solution and another 5-minute CPR period was performed using the other airway method. Pulmonary aspiration, defined as the presence of coloured solution below the vocal cords, was assessed by a blinded operator using bronchoscopy. A generalized linear mixed model was used for statistical analysis.Results: Protocol A: Forty-eight rescuers performed CPR on 11 cadavers. Median ventilation success was higher with SGA than BMV: 75.0% (IQR: 59.8-87.3) vs. 34.7% (IQR: 25.0-50.0), (p = 0.003). Gastric pressure and differential (maximum minus minimum) gastric pressure were lower in the SGA group: 2.21 mmHg (IQR: 1.66; 2.68) vs. 3.02 mmHg (IQR: 2.02; 4.22) (p = 0.02) and 5.70 mmHg (IQR: 4.10; 7.60) vs. 8.05 mmHg (IQR: 5.40; 11.60) (p = 0.05). CPR key times were not different between groups. Protocol B: Ten cadavers were included with 20 CPR periods. Aspiration occurred in 2 (20%) SGA procedures and 5 (50%) BMV procedures (p = 0.44).Conclusion: Use of SGA by rescuers improved the ventilation success rate, decreased intragastric pressure, and did not affect key CPR metrics. SGA use by basic life support rescuers appears feasible and efficient.

Effect of Early Supraglottic Airway Device Insertion on Chest Compression Fraction during Simulated Out-of-Hospital Cardiac Arrest: Randomised Controlled Trial

Early insertion of a supraglottic airway (SGA) device could improve chest compression fraction by allowing providers to perform continuous chest compressions or by shortening the interruptions needed to deliver ventilations. SGA devices do not require the same expertise as endotracheal intubation. This study aimed to determine whether the immediate insertion of an i-gel^® while providing continuous chest compressions with asynchronous ventilations could generate higher CCFs than the standard 30:2 approach using a face-mask in a simulation of out-of-hospital cardiac arrest. A multicentre, parallel, randomised, superiority, simulation study was carried out. The primary outcome was the difference in CCF during the first two minutes of resuscitation. Overall and per-cycle CCF quality of compressions and ventilations parameters were also compared. Among thirteen teams of two participants, the early insertion of an i-gel^® resulted in higher CCFs during the first two minutes (89.0% vs. 83.6%, p = 0.001). Overall and per-cycle CCF were consistently higher in the i-gel^® group, even after the 30:2 alternation had been resumed. In the i-gel^® group, ventilation parameters were enhanced, but compressions were significantly shallower (4.6 cm vs. 5.2 cm, p = 0.007). This latter issue must be addressed before clinical trials can be considered.

Evaluation of the insertion parameters and complications of the i-gel Plus airway device for maintaining patent airway during planned procedures under general anaesthesia: a protocol for a prospective multicentre cohort study

INTRODUCTION

Supraglottic airway devices represent a less invasive method of airway management than tracheal intubation during general anaesthesia. Their continued development is focused mainly on improvements in the insertion success rate and minimalisation of perioperative and postoperative complications. The i-gel Plus is a novel, anatomically preshaped supraglottic airway device which achieves a perilaryngeal seal due to a non-inflatable cuff made of a soft thermoplastic elastomer. The purpose of this cohort study is to assess the success rate of the i-gel Plus use during elective procedures under general anaesthesia, its intraoperative performance, and the degree of postoperative complications.

METHODS AND ANALYSIS

This is a multicentre, prospective, interventional cohort study. The enrolment will take place in seven centres in four European countries. We plan to enrol 2000 adult patients in total, who are scheduled for elective surgery under general anaesthesia, and with an indication for use of a supraglottic airway device for management of their airway. The study is projected to run over a period of 18 months. The primary outcome of the study is the total success rate of the i-gel Plus insertion in terms of successful ventilation and oxygenation through the device. Secondary outcomes include perioperative parameters, such as insertion time, seal/leak pressures, number of insertion attempts and postoperative adverse events and complications. Postoperative follow-up will be performed at 1 hour, 24 hours in all patients, and for selected patients at 3 and 6 months.

ETHICS AND DISSEMINATION

The cohort study has received the following ethical approvals: General University Hospital Prague, University Hospital Olomouc, University Military Hospital Prague, University Hospital Barcelona, University Hospital Lodz, Antrim Area Hospital, Craigavon Area Hospital, Office for Research Ethics Committees Northern Ireland. The results will be published in peer-reviewed journals and presented at relevant anaesthesia conferences.

TRIAL REGISTRATION NUMBER

ISRCTN86233693;Pre-results.

The effects of two-handed jaw thrust on i-gel™ placement in anesthetized non-paralyzed patients

BACKGROUND

I-gel^TM is a second-generation supraglottic airway device with a non-inflatable cuff. In this prospective randomized investigation, we evaluated the effects of two-handed jaw thrust technique on i-gel insertion in anesthetized non-paralyzed patients.

METHODS

Seventy-four adult patients were allocated to two groups (N.=37 each). In the jaw thrust group, two-handed jaw thrust technique was applied to facilitate i-gel insertion. In the control group, conventional i-gel insertion was performed. The success rate at the first attempt, air leakage pressure, insertion time, and postoperative sore throat incidence were recorded.

RESULTS

The success rate at the first attempt was higher in the jaw thrust group (37 [100%] vs. 31 [84%], difference of 16%, 95% confidence interval for the difference: 1 to 33%, P=0.03). The median air leakage pressure was higher in the jaw thrust group than in the control group (20 [interquartile range 13] vs. 17 [interquartile range 3] cmH<inf>2</inf>O, difference: 6, 95% confidence interval of the difference: 3 to 8, P<0.01). The mean insertion time was shorter in the jaw thrust group (27±14 vs. 41±29 seconds, difference: 14 seconds, 95% confidence interval of the difference: 3 to 24, P=0.01). The incidence of postoperative sore throat at the postoperative one hour was lower in the jaw thrust group (seven [20%] vs. 15 [41%], difference 22%, 95% confidence interval for the difference: -1 to 42%, P=0.04).

CONCLUSIONS

The two-handed jaw thrust technique facilitated i-gel insertion compared to the conventional technique in anesthetized non-paralyzed patients.

An unanticipated case of laryngeal mask failure due to hypopharyngeal mass: a case report

Supraglottic airway devices (SAD) have got popularity in the anesthetic practice owing to easy insertion, rapid airway access and lower incidence of complications. Igel® is a second generation SAD with a non‐inflatable cuff and gastric drainage channel. Despite ease of insertion, there are still cases of failure of Igel® insertion to secure airway. We are hereby presenting a case of unanticipated difficulty in Igel® insertion in a 35-years-old female due to a hypopharyngeal growth. This article aims to send a reminder that despite anticipated easy airway, definitive plan for securing airway should always be ready.

Comparison of Intracuff Pressure and Postoperative Sore Throat Following Use of Laryngeal Mask Airway Protector With or Without Nitrous Oxide Anesthesia

PURPOSE

In general anesthesia, the laryngeal mask airway (LMA) is a frequently used effective option. The effect of nitrous oxide on intracuff pressure of the LMA and postoperative sore throat is well known; however, there are no studies related to the second-generation LMA Protector. The purpose of this study was to determine the differences in intracuff pressure and postoperative sore throat, depending on the use of nitrous oxide during general anesthesia using the LMA Protector.

DESIGN

This randomized double-blind prospective study was conducted among 88 patients aged 20 to 70 years.

METHODS

The cuff pressure started with a baseline of 40 cm H₂O and was measured using a digital cuff pressure manometer for 30 minutes. Postoperative sore throat, dysphonia, dysphagia, and numeric rating scale scores were also recorded.

FINDINGS

Over time, the intracuff pressure of the nitrous oxide group increased significantly compared with that of the air group. Furthermore, postoperative sore throat and pharyngolaryngeal complications were not significantly different between the two groups.

CONCLUSIONS

Intracuff pressure of the LMA Protector increased during anesthesia using nitrous oxide. When the anesthesia time was less than 2 hours, however, there was no difference in postoperative sore throat.

Importance of the length of the myocardial sleeve in the superior vena cava in patients with atrial fibrillation

BACKGROUND

Pulmonary vein (PV) antrum isolation (PVAI) has proven to be a useful strategy for radiofrequency catheter ablation (RFCA) of atrial fibrillation (AF) worldwide. However, non-PV foci, especially from the superior vena cava (SVC), play an important role in initiating and maintaining AF.

METHODS

In all, 427 consecutive patients with non-valvular AF who were admitted to our hospitals to undergo RFCA of AF using an EnSite™ system were evaluated. The length from the top of the sinus node to the top of the myocardial sleeve of SVC (L-SVC), longer and shorter diameter of SVC of 1 cm above of junction of right atrium and SVC, and local activation time (LAT) of SVC were measured. Then, the SVC firing was evaluated by an intravenous administration of isoproterenol and adenosine triphosphate.

RESULTS

L-SVC, longer and shorter diameter of SVC, and LAT of SVC were significantly longer in the SVC firing group than non-SVC firing group (P < .05). Moreover, in accordance with the L-SVC, the frequency of the SVC firing significantly increased (P < .001). A univariate analysis and multivariate statistical analysis revealed that L-SVC longer than 37.0 mm (odds ratio 6.39) and longer diameter of SVC (odds ratio 6.78) were independent risk factors for SVC firing in patients with AF who underwent RFCA of AF.

CONCLUSIONS

In view of these findings, L-SVC longer than 37.0 mm longer diameter SVC longer than 17.0 mm may be one of the important predictors of SVC firing in patients with AF.

Severe acute respiratory syndrome coronavirus 2 infection risk during elective peri-operative care: a narrative review

The protection of healthcare workers from the risk of nosocomial severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection is a paramount concern. SARS-CoV-2 is likely to remain endemic and measures to protect healthcare workers against nosocomial infection will need to be maintained. This review aims to inform the assessment and management of the risk of SARS-CoV-2 transmission to healthcare workers involved in elective peri-operative care. In the absence of data specifically related to the risk of SARS-CoV-2 transmission in the peri-operative setting, we explore the evidence-base that exists regarding modes of viral transmission, historical evidence for the risk associated with aerosol-generating procedures and contemporaneous data from the COVID-19 pandemic. We identify a significant lack of data regarding the risk of transmission in the management of elective surgical patients, highlighting the urgent need for further research.

A multicenter and observational study of the Ambu™ AuraGain™ laryngeal mask in adult patients

PURPOSE

The main objective of this study was to evaluate the performance of the Ambu™ AuraGain™ device by determining its main parameters of use and complications.

METHODS

A total of 250 adult ASA physical status i to iii patients from five hospitals in Spain who received general anaesthesia with a supraglottic airway (SGA) device were enrolled in this study.

RESULTS

The primary outcome was analysed for 244 patients and a median OLP of 32 cm H2O (IQR 28-36 cm H2O) was obtained. Insertion was achieved at first attempt in 85% of cases, and overall in 98% of cases, in a median time of 15 s (12-22.5). We applied manoeuvres in 61% of patients to facilitate the process. Ventilation was effective in 97.2% of the interventions (95% CI 0.99-0.94) throughout the procedure. Insertion of the gastric tube was easily performed in 99.6% of the patients, and the vocal cords were viewed by fibrobronchoscopy in 96.3% of cases. Logistic regression analysis identified the use of sizes smaller than those recommended as a risk factor for low OLP (< 25 cm H2O). The main complication recorded was the presence of blood when withdrawing the SGA device (15%).

CONCLUSIONS

Our results confirm that the use of AuraGain allows airway management in a reliable and effective way achieving high OLP and low incidence of associated complications, establishing it as a useful alternative in the routine clinical setting of anaesthesiologists. AuraGain performance was consistent in all five centres.

Low skill fibreoptic intubation using i-gel™ and air-Q™ in simulated difficult airways: A randomised study in manikin and in patients

Background:

Fibreoptic intubation via a supraglottic device (SAD) is ‘low skill fibreoptic intubation’ (LSFOI). ‘Standard’ second generation SADs (i-gelTM) have a gastric port. ‘Specialised’ second generation SADs (air-QTM) are designed to facilitate LSFOI and have wider ventilation ports. Our hypothesis was that performance of LSFOI differs between i-gelTM and air-QTM in a manikin with a simulated difficult airway.

Methods:

Our primary outcome was fibreoptic intubation success rate. Our secondary outcomes included SAD insertion and LSFOI times. A difficult airway was simulated by applying a hard cervical collar to a manikin. Anaesthetists performed LSFOI serially using both SADs in a random sequence. In the manikin study, 80 anaesthetists were recruited. To test the robustness of the conclusion from our manikin study, we repeated the study in 22 anaesthetised patients. Patients were fitted with the same cervical collar and randomly allocated to either devices. We used McNemar’s statistical test to analyse our primary outcome of successful intubations and paired nominal data. A Wilcoxon signed-ranks test was used to analyse nonparametric paired data and a Mann–Whitney U test was used for unpaired data analysis where appropriate. A p-value of <0.05 was considered statistically significant.

Results:

In the manikin study, the i-gelTM was superior to the air-QTM for successful tracheal intubation (98.8% vs 83.8%, respectively; p=0.002) and LSFOI times (34.0 s vs 36.0 s, respectively; p=0.012). In the patient study, LSFOI success rates were not significantly different between i-gelTM and air-QTM (100% vs 91.6%, respectively; p=0.545) but intubation times were shorter (52.5 s vs 60.0 s, respectively; p=0.036).

Conclusion:

In conclusion, we obtained LSFOI success rates for the i-gelTM or air-QTM of 98.8% and 83.8% respectively in a manikin; and 100% and 91.6% respectively in patients. It is in fact ‘low skill’ as many participants were successful despite no prior experience with LSFOI. The i-gelTM is superior for LSFOI compared with the air-QTM. This is despite being a ‘standard’ second generation SAD as compared to a ‘specialised’ second generation SAD (air-QTM).

Trial Registration:

The manikin and patient studies were conducted after being approved by the SingHealth Centralised Institutional Review Board (CRB reference number 2014/2039 and 2016/2069, respectively). The patient study was registered at ClinicalTrials.gov (ID: NCT02663843).

Continuous infusion chemotherapy, radiotherapy, and FDG-PET are feasible during extracorporeal membrane oxygenation

Extracorporeal membrane oxygenation (ECMO) may be used in extreme circumstances for patients with a mediastinal mass and respiratory failure. We report on a young man with primary mediastinal B-cell lymphoma invading into the trachea, requiring a 40-day ECMO run who underwent fluorodeoxyglucose positron emission tomography (FDG-PET) imaging and treatment with concurrent mediastinal irradiation and continuous infusion chemotherapy while on this life-saving technology. This case illustrates that oncology patients may be managed by multidisciplinary teams for extended periods in extraordinary circumstances using multimodality therapies. Additionally, to our knowledge this is the first case to demonstrate the feasibility of FDG-PET imaging while on ECMO.

A prospective randomised trial to compare three insertion techniques for i-gel™ placement: Standard, reverse, and rotation

Background and Aims:

This prospective randomised study was done to compare standard, reverse, and rotation techniques of i-gel™ placement in terms of insertion characteristics and success rate.

Material and Methods:

After institutional ethics committee approval, 135 patients aged 18-50 years, ASA I and II undergoing elective surgery under general anesthesia were included. After induction of anesthesia, i-gel™ was inserted by standard, reverse, and rotation technique in Groups I, II, and III, respectively. The primary objective was mean time of insertion. Secondary variables included ease of insertion, first attempt success rate, manoeuvres required, fiberoptic view of placement, oropharyngeal leak pressure, ease of placement of nasogastric tube, and complications if any.

Results:

Mean time of insertion was 18.04 ± 5.65 s, 15.00 ± 5.72 s and 16.12 ± 5.84 s for groups I, II, and III, respectively. Time taken for insertion was shortest and significantly lower (P = 0.048) for group II compared to group I. Insertion time was comparable between rest of groups. The overall success rate in groups I, II, and III were 91.1%, 95.6%, and 93.3% respectively (P = 0.7). The first attempt success rate was 82.2%, 89%, and 84.4% in groups I, II and III, respectively (P = 0.07). Manoeuvres were required in five (12.19%) patients in group I, four (9.30%) patients in group II, and three (7.14%) patients in group III (P = 0.602). Complications occurred in eight, three, and three patients in groups I, II, and III, respectively.

Conclusion:

All techniques of i-gel insertion are equally good and choice of technique depends upon the experience and comfort of the investigator with the particular technique.

Comparison of gastric insufflation using LMA-supreme and I-gel versus tracheal intubation in laparoscopic gynecological surgery by ultrasound: a randomized observational trial

Background

The application of bedside ultrasound to evaluate gastric content and volume can assist in determining aspiration risk. Applying positive pressure ventilation via supraglottic airway devices (SAD) can result in a degree of gastric insufflation. This study assessed and compared the antral cross-sectional area (CSA) in patients undergoing laparoscopic gynecological surgery when managed with different SAD.

Methods

One hundred American Society of Anesthesiologists I or II female patients were assessed for inclusion in this study and divided into three groups of different ventilation devices. Patients were randomly allocated into three groups to receive LMA-Supreme (Group S), I-gel (Group I) or tracheal tube (Group T). The primary outcome was the antral cross-sectional area and secondary outcomes included haemodynamic parameters and postoperative morbidity such as sore throat, hoarseness, dry throat, nausea and vomiting.

Results

The antral CSA was not significantly different among three groups before induction (P = 0.451), after induction (P = 0.456) and at the end of surgery (P = 0.195). The haemodynamic variables were significantly higher in the tracheal tube group than in the LMA-Supreme and I-gel groups after insertion (P < 0.0001) and after removal (P < 0.01). Sore throat was detected in none in the I-gel group compare to two patients (6.7%) in the LMA-Supreme group and fifteen patients (50%) in the tracheal tube group. Hoareness was detected in one (3.3%) in the I-gel group compare to two patients (6.7%) in the LMA-Supreme group and eleven patients (36.7%) in the tracheal tube group.

Conclusions

The SADs do not cause obvious gastric insufflation. Thus, LMA-Supreme and I-gel can be widely used as alternative to endotracheal intubation for the short laparoscopic gynecological surgery.

Trial registration

This trial was registered at the Chinese Clinical Trial Registry (ChiCTR1800018212, data of registration, September 2018).

Recommendations for the evaluation and management of the anticipated and non-anticipated difficult airway of the Societat Catalana d'Anestesiologia, Reanimació i Terapèutica del Dolor, based on the adaptation of clinical practice guidelines and expert consensus

The Airway Division of the Catalan Society of Anaesthesiology, Intensive Care and Pain Management (SCARTD) presents its latest guidelines for the evaluation and management of the difficult airway. This update includes the technical advances and changes observed in clinical practice since publication of the first edition of the guidelines in 2008. The recommendations were defined by a consensus of experts from the 19 participating hospitals, and were adapted from 5 recently published international guidelines following an in-depth analysis and systematic comparison of their recommendations. The final document was sent to the members of SCARTD for evaluation, and was reviewed by 11 independent experts. The recommendations, therefore, are supported by the latest scientific evidence and endorsed by professionals in the field. This edition develops the definition of the difficult airway, including all airway management techniques, and places emphasis on evaluating and classifying the airway into 3 categories according to the anticipated degree of difficulty and additional safety considerations in order to plan the management strategy. Pre-management planning, in terms of preparing patients and resources and optimising communication and interaction between all professionals involved, plays a pivotal role in all the scenarios addressed. The guidelines reflect the increased presence of video laryngoscopes and second-generation devices in our setting, and promotes their routine use in intubation and their prompt use in cases of unanticipated difficult airway. They also address the increased use of ultrasound imaging as an aid to evaluation and decision-making. New scenarios have also been included, such as the risk of bronchoaspiration and difficult extubation Finally, the document outlines the training and continuing professional development programmes required to guarantee effective and safe implementation of the guidelines.

Comparison of the standard and triple airway maneuvering techniques for i-gel™ placement in patients undergoing elective surgery: a randomized controlled study

PURPOSE

The i-gel is a supraglottic airway device with non-inflatable cuff which can suffer insertion failure if its standard placement technique is implemented. The aim of this study was to compare the placement technique proposed by the manufacturer of i-gel with the triple airway maneuver in terms of successful device insertion time and first-attempt success.

METHODS

After ethics committee approval, 103 ASA I-III patients were randomly allocated to the standard or triple airway maneuver groups. In the standard Group, the i-gel was inserted in the sniffing position while, in the triple group, it was inserted using the triple airway maneuver consisting of head tilt, jaw thrust, and open mouth. The time taken for successful insertion, first-attempt success rate, i-gel position, airway complications, and hemodynamic responses were assessed.

RESULTS

Between the two groups patient characteristics were similar. Time for successful insertion was significantly shorter in the triple group (20 ± 7 s) than with the standard technique (32 ± 11 s; p < 0.001). Successful insertion at the first attempt was 78% and 92% for the standard and triple group, respectively (p = 0.092). The i-gel position, airway complications, and hemodynamic responses were similar in both groups.

CONCLUSION

The triple airway maneuver required less i-gel insertion time as compared with the standard placement technique. First-attempt success rates were similar with both techniques, although the triple airway maneuver was superior to the standard method as a rescue technique in failed insertions. We therefore recommend use of the triple airway maneuver in i-gel insertion.

Prospective, Randomized Comparison of the i-gel and the Self-Pressurized air-Q Intubating Laryngeal Airway in Elderly Anesthetized Patients

BACKGROUND

Age-related changes in upper airway anatomy may affect the overall performance of supraglottic airways significantly. The clinical performance of the i-gel and the self-pressurized air-Q intubating laryngeal airways with noninflatable cuffs for elderly populations remains unknown, unlike in children. Thus, we performed a prospective, randomized comparison of these 2 supraglottic airways in elderly patients undergoing general anesthesia.

METHODS

We recruited 100 patients, 65-90 years of age, who were scheduled for elective surgery under general anesthesia with muscle relaxation. The enrolled patients were allocated to the i-gel or self-pressurized air-Q group. We assessed oropharyngeal leak pressure as the primary outcome and fiberoptic view after placement and fixation of the airway and at 10 minutes after the initial assessment. The fiberoptic view was scored using a 5-point scale as follows: vocal cords not visible; vocal cords and anterior epiglottis visible, >50% visual obstruction of epiglottis to vocal cords; vocal cords and anterior epiglottis visible, <50% visual obstruction of epiglottis to vocal cords; vocal cords and posterior epiglottis visible; and vocal cords visible. We also investigated success rate and ease of insertion, insertion time, and manipulations during insertion as insertion variables, complications during maintenance and emergence periods, and postoperative pharyngolaryngeal complications including sore throat, dysphagia, and dysphonia.

RESULTS

After assessing for eligibility, 48 patients were allocated to each group. Oropharyngeal leak pressures were significantly higher in the i-gel group than in the self-pressurized air-Q group (P < .001) at the 2 measurement points. The raw mean difference at initial assessment and the median difference after 10 minutes were 5.5 cm H2O (95% confidence interval, 3.3-7.6 cm H2O) and 5.0 (95% confidence interval, 2.0-7.0 cm H2O), respectively. The initial scores of fiberoptic view were similar in the 2 groups. However, the self-pressurized air-Q supraglottic airway provided a significantly improved fiberoptic view at 10 minutes after initial assessment (P = .030). We found no statistically significant differences in insertion variables and complications between the 2 groups.

CONCLUSIONS

The i-gel provided better sealing function than the self-pressurized air-Q supraglottic airway according to the high oropharyngeal leak pressures in elderly patients during general anesthesia. The self-pressurized air-Q supraglottic airway had improved fiberoptic views in elderly patients during general anesthesia.

Supraglottic airway devices: current and future uses

Supraglottic airway devices have increasingly been used in anaesthesia since their invention in 1982. Now over half of general anaesthetic cases in the UK use them, and they have vital roles in difficult airway algorithms, pre-hospital use and emergency medicine. This article presents the current evidence regarding the complications of these devices, and compares these devices and endotracheal intubation. The technology of the newer generation devices has improved the safety profile, and they may be considered a better choice than endotracheal tubes in some cases. There may be a case for using these devices in a wider range of surgical and non-surgical cases.

Endosonographic evaluation of the mediastinum through the i-gel O2 supraglottic airway device

INTRODUCTION

Endobronchial ultrasound (EBUS) is an endoscopic diagnostic procedure combining flexible fibrobronchoscopy with ultrasound techniques; it allows transbronchial needle aspiration biopsy for the diagnosis and staging of mediastinal masses. We present our preliminary experience with the use of the i-gel O₂ supraglottic airway device for management of EBUS procedures.

METHODS

An observational study on 39 patients who underwent EBUS under general anesthesia was performed. Airways were managed with i-gel O₂ by anesthesiologists unfamiliar with it. Data collected included patient characteristics, i-gel O₂ positioning, mechanical ventilation, procedure, and complications occurring during and after the EBUS.

RESULTS

The i-gel airway was successfully positioned during the first attempt in 34/39 cases (87.2%). No failed positioning was recorded. The EBUS scope easily passed through the i-gel in all patients and in 14 (35.6%) cases it was also inserted through the esophagus allowing the examination or fine needle aspiration of paraesophageal lymph nodes. In one case, during the EBUS procedure, the i-gel was dislocated but easily put in place again. During EBUS, air leakages were significant in 2 cases (5.1%) and minimal in 14 cases (35.9%). A brief self-solved laryngospasm and a bronchospasm during bronchoscopy were recorded. After recovery, no patients had dysphagia; mild odynophagia and pharyngodinia were referred by 2 (5.1%) and 12 (30.1%) patients, respectively.

CONCLUSIONS

The i-gel O₂ airway is easy to position and manage even for anesthesiologists unfamiliar with it. This supraglottic airway device is suitable for a complete endosonographic evaluation of the mediastinum.

Getting it right first time: time to simplify our approach to the airway by using our best tools first

Deciding on the techniques and equipment to use when managing a patient’s airway during anaesthesia is a complex process. It is influenced by many factors, including the type of surgery being undertaken, patient co-morbidities, perceived risk of airway difficulty or pulmonary aspiration and the availability of more advanced equipment. While there are many guidelines for management of the unanticipated difficult airway, there are few if any for routine airway management. It is likely that current practices are heavily influenced by national and institutional norms, personal experiences and preferences of the individual anaesthetist involved.

Choosing appropriate size of I-Gel® for initial success insertion: a prospective comparative study

PURPOSE

The optimal size of the I-Gel^® remains unclear since the manufacturer's weight-based formula (size 3 for weight < 50 kg, size 4 for weight 50-90 kg, and size 5 for weight > 90 kg) for the laryngeal mask airway I-Gel^® is not evidence-based. We hypothesised that sex may also guide the choice of I-Gel^® size.

METHODS

Insertion success rates of the I-Gel^® chosen according to the weight-based formula were prospectively recorded and compared with those of a patients' cohort ventilated with an I-Gel^® chosen according to the sex-based formula recorded. Two periods of 18 months were randomised in three independent hospitals in France to study each choice strategy. Patients requiring I-Gel^® size change were compared with those who where successfully ventilated with the initially chosen device. Complications linked to the I-Gel^® and factors for changing the size of the I-Gel^® were also recorded and analysed.

RESULTS

Data from 900 patients were prospectively collected in the three participating centres. The overall initial ventilation was inadequate in 80 cases, including 7% (n = 31) in the weight-based group and 3% (n = 13) in the sex-based group (P = 0.01). In the weight-based group, changing size of I-Gel^® was successful in 28 (90%) cases. In the sex-based group, changing size of I-Gel^® was useful in 1 case only. Endotracheal tube insertion was necessary in 15 cases despite changing I-Gel^® size, including 3 cases in the weight-based group and 12 cases in the sex-based group. Ease of insertion and postoperative pharyngo-laryngeal problems were similar between groups with or without changing size of I-Gel^®.

CONCLUSION

Adequate ventilation is achieved most of the time using size selection for the I-Gel^® laryngeal mask airway according to the manufacturer's weight-based formula. However, our results suggest that the sex-based formula in healthy, anaesthetised, adult patients may also be appropriate for I-Gel^® size choice.

Comparison of I-gel for general anesthesia in obese and nonobese patients

Context:

I-gel is a second-generation supraglottic airway device. Despite several studies on i-gel, there are very few studies on the use of i-gel in obese patients.

Aims:

The aim of the study was to compare the clinical performance of i-gel between obese and nonobese patients.

Settings and Design:

Prospective, controlled, nonrandomized, hospital-based study.

Subjects and Methods:

After obtaining informed consent, patients were divided into two groups of 16 patients each: group O consisted of patients with body mass index (BMI) >30 kg/m² and Group C consisted of patients with BMI 18.5–29.9 kg/m². I-gel was inserted after induction of anesthesia and muscle relaxation. Oropharyngeal leak pressure (OLP) (primary outcome variable), leak fraction, time taken to insert the device, ease of insertion, fiberoptic view of glottis through i-gel's airway tube, and adverse effects were recorded.

Statistical Analysis Used:

Data were analyzed using SPSS 20. Continuous, ordinal, and categorical variables were analyzed using students t-test, Mann–Whitney U–test, and Fischer's exact test, respectively.

Results:

OLP was slightly higher in Group O (25.38 ± 4.79 cm H₂O) but was not statistically different than Group C (27.38 ± 4.38 cm H₂O). Other parameters except weight and BMI (which were higher in Group O) were statistically similar in both groups. There was no statistical difference in side effects.

Conclusions:

We concluded that i-gel is as effective in obese patients as in nonobese patients when used for securing the airway for surgical procedures.

Anaesthesia management for bronchoscopic and surgical lung volume reduction

Optimizing the patient's condition before the lung volume reduction (LVR) according to recommendations by American College of Cardiology/American Heart Association (ACC/AHA) guideline on perioperative cardiovascular evaluation is mandatory. Implementation of a multimodal analgesia concept and the use short-acting anaesthetics enhances recovery and avoids postoperative pulmonary complications. Normovolemia, normothermia, lung protective ventilation and an evidence-based concept of airway management (i.e., double-lumen tube, bronchus blocker) are suggested for intraoperative management of surgical lung volume reduction (SLVR). General anaesthesia (using remifentanil, propofol and mivacurium) with an i-gel^® supraglottic airway device should be used for bronchoscopic lung volume reduction (BLVR). Jet ventilation through rigid bronchoscopy or with a jet catheter may be an alternative concept. Experienced consultants should perform anaesthesia for LVR.

I-gel™ May be the Device of Choice for Controlled Ventilation in Patients with Hemophilia Undergoing Abdominal Laparoscopic Surgery

Haemophilia is an inherited bleeding disorder with variable deficiency of Factor VIII in the plasma and is characterised by bleeding into joints, muscles and tissues either spontaneously or in response to trivial trauma. Perioperative care requires multidisciplinary involvement. Perioperative management involves the risk of excessive bleeding from surgical site as well as spontaneous bleeding into the brain in response to surgical stress in patients with previous history of intracerebral haemorrhage. Airway management of such patients during anaesthetic intervention is a challenge and entails the risk of life threatening haemorrhage into the airway. The I gel Supraglottic airway device may be best suited for the purpose considering its soft elastomeric non-inflatable cuff, ease of insertion, availability of gastric suction port and minimal leak fraction on controlled ventilation. The I Gel may be solution to avoiding airway instrumentation in patients with bleeding disorders. It may be an alternative to endotracheal intubation in patients with Haemophilia undergoing surgery.

Direct and indirect low skill fibre-optic intubation: A randomised crossover manikin study of six supraglottic airway devices

Background and Aims:

Fibre-optic intubation (FOI) through supraglottic airway devices (SADs) is useful in the management of the difficult airway. We compared two methods of FOI through seven SADs in a randomised crossover manikin study to assess each device's performance and discuss implications on SAD selection.

Methods:

Thirty anaesthetsiologists, 15 seniors and 15 juniors, each performed low skill FOI (LSFOI) with seven SADs using both 'direct' and 'indirect' methods. The order of method and device used were randomised. The primary end point was success rate of intubation; secondary end points were time taken for intubation, incidence of difficulties with direct and indirect LSFOI and operator device preference. Statistical analysis was with univariable analysis and comparison of proportions.

Results:

Data from six devices were analysed due to a protocol breach with one SAD. There was no difference in intubation success rate across all SADs and intubation methods. Intubation time was significantly shorter in AmbuAuragain than other SADs and shorter with the direct method of LSFOI than the indirect method (mean difference of 6.9 s, P = 0.027). Ambu Auragain had the least SAD and bronchoscope-related difficulties. Seniors had significantly shorter mean intubation times than juniors by 11.6 s (P = 0.0392). The most preferred SAD for both methods was AmbuAuragain.

Conclusion:

Low skill FOI consistently achieves a high intubation success rate regardless of experience, choice of method, or SAD used. SAD design features may significantly affect the performance of low skill FOI.

Assessment of awake i-gel™ insertion for fiberoptic-guided intubation in patients with predicted difficult airway: A prospective, observational study

Background and Aims:

Orotracheal intubation (OTI) with fiberoptic bronchoscope (FOB) in spontaneous ventilation is one of the main techniques for patients with predicted difficult airway. Latest generation supraglottic airway devices have been designed to allow OTI through them. We assessed the safety and effectiveness of FOB-guided OTI through i-gel™ device which was inserted in spontaneously breathing patients with predicted difficult airway.

Material and Methods:

Eighty-five patients with difficult airway predictors were included. The i-gel was inserted under oropharyngeal local anaesthesia and sedation. After checking the adequate ventilation through the i-gel with capnography curve, general anaesthesia was induced in order to introduce the endotracheal tube guided by FOB. We recorded the i-gel insertion time (t_gel), intubation time (t_int), O₂ saturation in pulse oximetry (SpO₂) at different times: basal (t₀), after 3 min of preoxygenation with a face mask at 100% FiO₂ (t₁), after i-gel mask insertion (t₂) and after intubation (t₃). Adverse events during the procedure were also recorded.

Results:

All patients were successfully intubated. SpO₂ values were: 96.9 ± 1.2 (t₀), 99.0 ± 0.9 (t₁), 96.2 ± 2.4 (t₂), 96.0 ± 2.5 (t₃). t_gel and t_int were 38.0 ± 7.8 s and 36.5 ± 5.6 s, respectively. No serious adverse events were recorded and no patient suffered airway trauma.

Conclusion:

I-gel insertion in spontaneous ventilation secures the airway before achieving fiberoptic intubation without the occurrence of adverse events. More studies might be necessary in order to confirm the results presented, but we consider that the technique described is a safe and effective alternative to classic OTI with FOB in spontaneously breathing patients with predicted difficult airway.

Guidelines for the management of tracheal intubation in critically ill adults

These guidelines describe a comprehensive strategy to optimize oxygenation, airway management, and tracheal intubation in critically ill patients, in all hospital locations. They are a direct response to the 4^th National Audit Project of the Royal College of Anaesthetists and Difficult Airway Society, which highlighted deficient management of these extremely vulnerable patients leading to major complications and avoidable deaths. They are founded on robust evidence where available, supplemented by expert consensus opinion where it is not. These guidelines recognize that improved outcomes of emergency airway management require closer attention to human factors, rather than simply introduction of new devices or improved technical proficiency. They stress the role of the airway team, a shared mental model, planning, and communication throughout airway management. The primacy of oxygenation including pre- and peroxygenation is emphasized. A modified rapid sequence approach is recommended. Optimal management is presented in an algorithm that combines Plans B and C, incorporating elements of the Vortex approach. To avoid delays and task fixation, the importance of limiting procedural attempts, promptly recognizing failure, and transitioning to the next algorithm step are emphasized. The guidelines recommend early use of a videolaryngoscope, with a screen visible to all, and second generation supraglottic airways for airway rescue. Recommendations for emergency front of neck airway are for a scalpel-bougie-tube technique while acknowledging the value of other techniques performed by trained experts. As most critical care airway catastrophes occur after intubation, from dislodged or blocked tubes, essential methods to avoid these complications are also emphasized.

Clinical Comparison of I-Gel Supraglottic Airway Device and Cuffed Endotracheal Tube for Pressure-Controlled Ventilation During Routine Surgical Procedures

Objective

Recently, there has been a trend favouring the use of supraglottic airway devices over endotracheal tubes (ETT) during short surgical procedures. In this study, we are going to assess the suitability of one such supraglottic airway device, i-gel, for pressure-controlled ventilation (PCV) during routine surgical procedures.

Methods

The airway management for 60 patients was done with either i-gel (Group I) or cuffed tracheal tube (Group E) for this prospective, randomised, double-blinded study. Insertion time, number of attempts, ease of insertion and haemodynamic monitoring were recorded before, during and after insertion of these devices. Airway leak tests, leak volume and leak fraction were measured at 15, 20 and 25 cm H₂O PCV, and pharyngolaryngeal morbidity was evaluated postoperatively.

Results

I-gel is easier to insert than a tracheal tube (p=0.0056). The increase in heart rate and MAP was higher following insertion of tracheal tube in the first few minutes (p<0.001) and subsequently became comparable between the two groups. The leak volume and leak fraction between the two groups were comparable at 15 cm H₂O PCV, but significant difference was seen at 20 and 25 H₂O PCV between the two groups (p=0.232, p<0.001, p<0.001). Thirty minutes later, the leak volume and leak fraction between groups were comparable at 15 cm H₂O PCV (p=0.495, p=0.104) but not at 20 and 25 H₂O PCV (p<0.001, p<0.001). Pharyngolaryngeal morbidity was significantly lesser in the i-gel group.

Conclusion

I-gel provides a reasonable alternative to cuffed ETT for pressure-controlled ventilation provided the pressures can be limited to 15 to 20 cm H₂O.

Pediatric supraglottic airway devices in clinical practice: A prospective observational study

BACKGROUND

Supraglottic airway devices (SGA) are commonly used in pediatric anesthesia and serve as primary or back-up devices for difficult airway management. Most SGA are marketed without proper clinical evaluation. The purpose of this study was to evaluate the performance of the pediatric LMA Supreme™, Air-Q® and Ambu® Aura-i™.

METHODS

This prospective observational study was performed at Bern University Hospital, Switzerland. With ethics committee approval and a waiver for written informed consent 240 children undergoing elective surgery with an ASA class I-III and a weight of 5-30 kg were included. Three different pediatric supraglottic airway devices were assessed: The LMA Supreme™, Air-Q® and Ambu® Aura-i™. Primary outcome parameter was airway leak pressure. Secondary outcome parameters included first attempt and overall success rate, insertion time, fiberoptic view through the SGA, and adverse events. The primary hypothesis was that the mean airway leak pressure of each tested SGA was 20 cmH₂O ± 10%.

RESULTS

None of the SGA showed a mean airway leak pressure of 20 cmH₂O ± 10%, but mean airway leak pressures differed significantly between devices [LMA Supreme™ 18.0 (3.4) cmH₂O, Air-Q® 15.9 (3.2) cmH₂O, Ambu® Aura-i™ 17.3 (3.7) cmH₂O, p < 0.001]. First attempt success rates (LMA Supreme™ 100%, Air-Q® 90%, Ambu® Aura-i™ 91%, p = 0.02) and overall success rates (LMA Supreme™ 100%, Air-Q® 91%, Ambu® Aura-i™ 95%, p = 0.02) also differed significantly. Insertion times ranged from 20 (7) seconds (Air-Q®) to 24 (6) seconds (LMA Supreme™, <p = 0.005). Insertion was rated easiest with the LMA Supreme™ (very easy in 97% vs. Air-Q® 70%, Ambu® Aura-i™ 72%, p < 0.001). Fiberoptic view was similar between the SGA. Adverse events were rare.

CONCLUSIONS

Airway leak pressures ranged from 16 to 18 cmH₂O, enabling positive pressure ventilation with all successful SGA. The highest success rates were achieved by the LMA Supreme™, which was also rated easiest to insert.

TRIALS REGISTRATION

ClinicalTrials.gov , identifier NCT01625858 . Registered 31 May 2012.