Single-use Supraglottic Airway Device Research Articles

Clinical performance of the LMA Protector\u2122 airway in moderately obese patients

BackgroundThe 4th National Audit Project of The Royal College of Anaesthetists and The Difficult Airway Society (NAP4) reported a higher incidence of supraglottic airway device (SAD) related pulmonary aspiration in obese patients especially with the first-generation SADs. The latest single-use SAD, the Protector™ provides a functional separation of the respiratory and digestive tracts and its laryngeal cuff with two ports allowing additional suction in tandem with the insertion of a gastric tube. The laryngeal cuff of LMA Protector™ allows a large catchment reservoir in the event of gastric content aspiration.MethodsWe evaluated the performance characteristics of the LMA Protector™ in 30 unparalysed, moderately obese patients. First attempt insertion rate, time for insertion, oropharyngeal leak pressure (OLP), and incidence of complications were recorded.ResultsWe found high first and second attempt insertion rates of 28(93%) and 1(33%) respectively, with one failed attempt where no capnography trace could be detected, presumably from a downfolded device tip. The LMA Protector™ was inserted rapidly in 21.0(4.0) seconds and demonstrated high OLP of 31.8(5.4) cmH2O. Fibreoptic assessment showed a clear view of vocal cords in 93%. The incidence of blood staining on removal of device was 48%, postoperative sore throat 27%, dysphagia 10% and dysphonia 20% (all self-limiting, resolving a few hours postoperatively).ConclusionsWe conclude that the LMA Protector™ was associated with easy, expedient first attempt insertion success, demonstrating high oropharyngeal pressures and good anatomical position in the moderately obese population, with relatively low postoperative airway morbidity.Trial registrationAustralian New Zealand Clinical Trials Registry, ACTRN12617001152314. Registered 7 August 2017.

Influence of temperature on volume, weight and density changes of i-gel masks.

The i-gel mask is a second-generation, single-use supraglottic airway device which does not have an inflatable cuff. The cuff consists of a thermoplastic elastomer and its mechanism of sealing still remains unclear. Various theories such as temperature-dependent changes in hardness and volume expansion as well as fluid absorption have been discussed. The aim of the present study is to investigate changes in volume, weight and density caused by temperature changes. Three i-gel masks (sizes 3, 4 and 5) were heated in a water bath from 10°C to 50°C in 5°C steps. The changes in weight, volume, and density were measured at each temperature step. In a second study, the identical parameters of masks (n = 5 of sizes 3, 4 and 5) used in patients were investigated. Results of volume and density between benchtop and patient measurements were examined for correlation. All masks investigated, regardless of the size, showed a significant linear temperature-dependent volume expansion (sizes 3, 4 and 5: P < 0.001), a weight increase (sizes 3: P = 0.018; 4: P = 0.027; and 5: P = 0.006) and a linear decrease in density (sizes 3, 4 and 5: P < 0.001). There was a very strong correlation between the results of benchtop and patient measurements (volume: P < 0.001; density: P < 0.001). We observed significant changes in all three properties investigated. Thus, a temperature-dependent volume expansion and weight increasement was observed, which can be considered as a further explanation for improved sealing after insertion.

A new second-generation supraglottic airway device (Ambu® AuraGain•) versus intubating laryngeal mask airway as conduits for blind intubation - A prospective, randomised trial.

Background and Aims:The Ambu® AuraGain• is a new single-use supraglottic airway device with gastric channel, designed to facilitate intubation. The study aimed to assess the success rates of proper placement and intubation using Ambu® AuraGain• compared with intubating laryngeal mask airway (ILMA).Methods:One hundred and twenty patients (18–60 years) were enrolled into this prospective, randomised, comparative study. After inducing general anaesthesia, appropriate size ILMA (group I)/Ambu® AuraGain• (group A) was placed as per the manufacturer's recommendations and correct placement was confirmed. Appropriate size endotracheal tube was passed through the device. The success rate of insertion and intubation, number of attempts, Cormack–Lehane grading before insertion and haemodynamics were recorded. Data were analysed using Mantel–Haenszel Chi-square test, Student's t-test and Fisher's exact test.Results:Demographic and airway parameters were uniformly distributed in both the groups. The success rate for insertion was 100% in both devices. The success rate for intubation was 96.6% (58/60) in group I and 36.6% in group A (P < 0.001). In group I, patients with mean thyromental distance >7.62 ± 0.75 cm had higher successful intubation compared with patients with mean thyromental distance <5.25 ± 0.35 cm (P = 0.014). Cormack–Lehane grading did not correlate with intubation attempts or success rate in group I (P = 0.45), whereas in group A the rate of successful blind intubation with Cormack–Lehane grade 1 was 50% (19/38).Conclusion:Both devices have 100% insertion success, though Ambu® AuraGain• has lower success rate for facilitating intubation compared with ILMA.

Laryngeal mask airway versus i-gel for airway maintenance during general anesthesia with controlled ventilation in pediatrics

Background Supraglottic airway devices have become prevalent in children because they are typically more user-friendly than a face mask and avoid many of the problems associated with endotracheal intubation. i-gel is a new single-use supraglottic airway device without an inflatable cuff. Pediatric i-gel is now available in four different sizes, 1, 1.5, 2, and 2.5, on the basis of body weight. Patients and methods This study was carried out in Alexandria University Hospitals on 70 patients of American Society of Anesthesiologists grade I and II, aged 3–6 years. They were classified randomly into two equal groups of 35 patients each and admitted to undergo elective surgery under general anesthesia with controlled ventilation in the supine position without head and neck manipulation. In group I, a classic laryngeal mask was used and in group II, i-gel was used to maintain a patent airway during anesthesia. The devices were compared in terms of insertion success, hemodynamic responses, oropharyngeal sealing pressure, airway interventional requirements during maintenance, and postoperative complications. Results The time of insertion of i-gel was significantly shorter than that of the classic laryngeal mask airway (cLMA) (P Conclusion Both the i-gel and the cLMA are suitable devices for controlled ventilation for pediatric patients undergoing short surgical procedures who are not at risk of aspiration. The insertion time of i-gel was less than that of cLMA and airway sealing pressure of i-gel was higher than that of cLMA.

Insertion characteristics of three supraglottic airway devices: A randomized comparative trial

Background I-gel is a new single-use supraglottic airway device without an inflatable cuff. The aim of this study was to compare I-gel, a Proseal laryngeal mask airway (PLMA), and a laryngeal tube (LT) for ease of insertion, hemodynamic effects of insertion, and associated airway morbidity. Patients and methods Seventy-five adult patients, both sexes, were assigned randomly to I-gel (I), PLMA (P), and LT (L) groups according to the supraglottic device applied. Insertion time, airway sealing pressure, insertion success rate, insertion-associated hemodynamic effects, ease of gastric tube insertion, and associated airway morbidities were assessed. Results Demographic data and duration of both surgery and anesthesia in the three groups were comparable. Insertion time (s) was significantly shorter in group I (18.9 ± 0.9) compared with group P (26.2 ± 1.1) and group L (26.2 ± 1.0). Airway sealing pressure (cm H 2 O) was higher in group P (29.6 ± 1.2) compared with group I (26.0 ± 1.0) and group L (22.9 ± 0.9). The success rate at the first insertion attempt was higher in group I (96.0%) compared with group P (84.0%) and group L (88%). Blood-stained devices and occurrence of postoperative sore throat were lower in group I than the P and L group, with no significant differences. Heart rate, mean arterial pressure, and cardiac index were significantly increased in the postinsertion period in the P and L group compared with group I. Conclusion In the I-gel group, higher insertion success rate, and lower both hemodynamic changes and airway morbidities were noted compared with PLMA and LT. However, airway sealing ability was better with PLMA.

Cross-Over Assessment of the AmbuAuraGain, LMA Supreme New Cuff and Intersurgical I-Gel in Fresh Cadavers

Background: The AmbuAuraGain is a new single-use supraglottic airway device with gastric channel designed to facilitate intubation. The aim of the study was to assess the anatomic position and the performance of the AuraGain in fresh cadavers compared to that of the Intersurgical i-gel and LMA Supreme New Cuff. Methods: The 3 devices were inserted in random order in 7 fresh cadavers without difficult airway criteria. The assessed items were: Insertion time, number of attempts and ease of insertion, airway seal pressure, ease of gastric tube insertion, endoscopic view of vocal cords, efficacy of guided tracheal intubation through the AuraGain and i-gel, and anatomic fit by lateral X-ray and neck dissections. Results: All devices were successfully inserted within 3 attempts, except for one case of the LMA Supreme. Adjusting manoeuvres were often required to accomplish correct insertion. A 16 G gastric tube was easily advanced through all AuraGain and LMA Supreme devices. Fiberoptic tracheal intubation was effectively achieved through all AuraGain and i-gel devices in less than 60 s. Lateral X-ray and neck dissections confirmed optimal alignment of all devices with the respiratory and digestive tracts. Conclusions: Insertion of the new AmbuAuraGain required adjusting manoeuvres in some cases, as observed with the other two devices, and achieved similar airway seal pressures. Passage of a large bore gastric tube was as fast as with the LMA Supreme and ease of guided intubation was similar to that of the i-gel.

A comparison of supraglottic airway i-gel™ vs. classic laryngeal mask airway in small children

Backgroundi-gel™ is a new single-use supraglottic airway device without an inflatable cuff. This study was designed to compare the usefulness of i-gel™ versus a classic laryngeal mask airway (cLMA) in small children.MethodsSixty-three children (age range : 4-72 months) were randomly assigned to an i-gel™ or cLMA group. We evaluated hemodynamic data, airway sealing ability, the success rate of insertion, and adverse events including an inadvertent sliding out during ventilation.ResultsDemographic data and hemodynamic data obtained immediately after the insertion of these devices did not differ between the two groups. The success rates for insertion on the first attempt were 77 and 84% for i-gel™ and cLMA, respectively (P = 0.54), and the overall success rates were 87 and 100% respectively (P = 0.14). There were no significant differences in terms of airway leak pressure. The inserted i-gel™ inadvertently slid out in 8 of 31 patients but only one sliding out case occurred in the cLMA group (P = 0.02). There were no differences between the groups in terms of other side effects (e.g., coughing, bleeding) associated with the use of i-gel™ and cLMA (P = 0.75 and 0.49, respectively).ConclusionsOropharyngeal leak pressure and insertion success rate of i-gel™ are similar to those of cLMA. However, i-gel™ is prone to inadvertent sliding out of the mouth in small children. Therefore, it is recommended that the i-gel™ should be secured more tightly to avoid displacement of the device.

Successful tracheal intubation using fiberoptic bronchoscope via an I-gel™ supraglottic airway in a pediatric patient with Goldenhar syndrome -A case report-

The I-gel™ is a single-use supraglottic airway device introduced in 2007 which features a non-inflatable cuff and allows passage of a tracheal tube owing to its large diameter and short length of the airway tube. In this case, the authors experienced a difficult airway management on a 4-year-old boy with underlying Goldenhar syndrome who underwent a tonsillectomy. Intubation using a laryngoscope was unsuccessful at the first attempt. In the following attempt, we used the I-gel™ supraglottic airway for ventilation and were able to achieve successful intubation with a cuffed tube by using fiberoptic bronchoscope through the I-gel™ supraglottic airway. The authors suggest that I-gel™ is a useful device for ventilation and it has many advantages for tracheal intubation in pediatric patients with difficult airway.

Initial experience of the i-gel supraglottic airway by the residents in pediatric patients

Insertion of a laryngeal mask airway (LMA) is occasionally difficult in children because of their anatomical features and variations. A new single-use supraglottic airway device, the i-gel airway, was recently introduced. The objective of this study was to show the initial experience of the i-gel airway device by the residents for pediatric patients. With approval from the local ethics committee and parental informed consent, 70 children undergoing minor surgery in the supine position, ASA score I-II, were investigated. Exclusion included patients having thoracic, neurosurgical, spine, and otolaryngological procedures. Patients were divided into three groups: group 1 was airway size 1.5 for patients weighing 5-12 kg, group 2 was size 2 for 10-25 kg, and group 3 was size 2.5 for those weighing 25-35 kg. The following seven characteristics were evaluated: (1) ease of the i-gel and gastric tube insertion; (2) leak pressure; (3) tidal volume/body weight at leak pressure point; (4) fiberscope score; (5) insertion time; (6) hypoxia rate (laryngospasm); and (7) coughing and trace of bleeding. The overall insertion success rate and the success rate at first attempt were 99% and 94%, respectively. Gastric tube insertions were easy in all patients. The overall leak pressure was 23 ± 5 cmH(2)O. The tidal volume per body weight was 24 ± 10 ml/kg. A good view of the fiberscope was achieved in 79%. In group 1 (size 1.5), one failed insertion, two dislocations, and one dysphonia were observed. Hypoxia rate was 1%. There was no case with coughing and trace of bleeding. These results show that the i-gel airway is a safe and effective device for use by residents who do not have experience with insertion of a pediatric LMA. However, using size 1.5, special caution should be taken to protect the infant airway, similar to what has been previously reported for other airway devices.

Randomized trial comparing the i-gel™ and Magill tracheal tube with the single-use ILMA™ and ILMA™ tracheal tube for fibreoptic-guided intubation in anaesthetized patients with a predicted difficult airway

The i-gel™ is a single-use supraglottic airway device (SAD) that allows fibreoptic-guided tracheal intubation through the device. Until now, no prospective data for this procedure are available. Therefore, in a prospective randomized controlled trial, we evaluated fibreoptic-guided tracheal intubation with a standard Rüsch™ PVC tracheal tube (TT) through the i-gel™ compared with the single-use ILMA™ (sILMA™) TT through the sILMA™ in patients with a predicted difficult airway. With ethics committee approval and written informed consent, 160 patients were randomly assigned to either SAD. After placement of the SAD, a fibreoptic bronchoscope was introduced into the trachea as a railroad for the TT. Primary outcome variable was the first-attempt fibreoptic-guided intubation success rate. Secondary variables included time for insertion and intubation, airway leak pressures, fibreoptic view, and adverse events. Data are presented as mean (sd) or percentages. A P-value of < 0.05 was considered statistically significant. Fibreoptic-guided intubation was successful at the first attempt in 76 patients (96%) using the i-gel™ and in 71 patients (90%) using the sILMA™ (P=0.21). Most of the failed intubations were rescued by conventional laryngoscopy. Airway leak pressure was higher for the sILMA™. There were no problems during removal of either type of SAD. Fibreopic-guided tracheal intubation through the i-gel™ using a standard Rüsch™ Magill TT is successful and an alternative to the sILMA™ with the sILMA™ TT.

I-gel vs cuffed tracheal tube during volume controlled ventilation in elective laparoscopic cholecystectomy

BackgroundIn this study we tested the new, single-use supraglottic airway device; i-gel with a non-inflatable cuff as an effective airway as conventional endotracheal tube. Gas leak was measured and compared with that of cuffed tracheal tube during volume controlled ventilation in elective laparoscopic cholecystectomy.MethodsSixty patients, ASA I–II, were randomly selected to the study. Standard anaesthetic technique was used for all patients. The i-gel was then inserted. The lungs were ventilated at three different tidal volumes (6, 8 and 10 ml kg−1) using volume controlled ventilation (VCV). The leak volume was calculated as the difference between the inspired and expired tidal volumes. The leak fraction was also calculated as the leak volume divided by the inspired tidal volume. These observations were recorded with every tidal volume before and after pneumoperitoneum with the i-gel and the conventional tracheal tube.ResultsBefore pneumoperitoneum there was no significant difference in leak fraction between i-gel and tracheal tube at 6 and 8 ml kg−1 tidal volume. Significant differences were found after pneumoperitoneum at 8 and at 10 ml kg−1 before and after pneumoperitoneum.ConclusionWe suggest that i-gel can be used as an alternative device to endotracheal tube during VCV for laparoscopic cholecystectomy provided that peak pressure does not exceed leak pressure.

Modified i-gel Airway for Oral Surgery

The i-gel (Intersurgical Ltd, Wokingham, UK) is a relatively new, single-use supraglottic airway device for use during general anesthesia. The main components of this device are a noninflatable gel-like cuff that is claimed to achieve a perfect fit to the pharyngeal and laryngeal structure and a thick airway tube with a gastric drain tube orifice.1 We often use the i-gel during dental procedures and minor oral surgery. However, its thick airway tube occasionally interferes with surgical access. We describe a modified i-gel airway for use during oral surgeries. Our idea was to use a reinforced tracheal tube, also called a coiled-wire reinforced tracheal tube, along with the i-gel airway to avoid interference with the surgical field. A size number 4 i-gel airway was cut to an airway tube length of 5.5 cm (Figure 1A). A reinforced tracheal tube (inner diameter 7.5 mm, outer diameter 10.2 mm, Rusch, Kernen, Germany) was then passed into the i-gel's airway tube. The distal end of the reinforced tracheal tube just fits into the i-gel so that the tip does not protrude through its ventilation hole (Figure 1B). To fix the i-gel even more tightly, the cuff of the reinforced tracheal tube was inflated with approximately 2.5 mL of air. Figure 1. A. Cut i-gel airway and reinforced tracheal tube. B. Cut i-gel airway with reinforced tracheal tube in it. To fix the i-gel tightly, the cuff of the reinforced tracheal tube was inflated with air. Insertion of the i-gel into the airway can be readily achieved by gripping its thick airway tube part and using the index and middle fingers to position it into the hypopharynx in the usual manner. However, removal should only be performed by gripping the thick airway tube part of the i-gel using Magill forceps under direct laryngoscopy so that the reinforced tracheal tube does not separate from the i-gel and leave it lodged in the oropharyngeal cavity. Using this modified i-gel airway, we successfully administered general anesthesia to more than 15 outpatients presenting for dental treatment and minor oral surgery. We believe that this modified i-gel airway is a useful device for these surgeries, provided that it is only removed by pulling on the i-gel base and not on the reinforced tracheal tube.

The supraglottic airway I-gel in comparison with ProSeal laryngeal mask airway and classic laryngeal mask airway in anaesthetized patients

The I-gel is a new single-use supraglottic airway device without an inflatable cuff. This study was designed to investigate the usefulness of the I-gel compared with the classic laryngeal mask airway (cLMA) and ProSeal laryngeal mask airway (pLMA) in anaesthetized, paralysed patients. The American Society of Anesthesiologists physical status I-II patients (n = 167) scheduled for orthopaedic surgery were included in this prospective study. General anaesthesia was achieved with intravenous infusion of propofol, remifentanil and rocuronium. The patients were randomly assigned to I-gel, pLMA and cLMA groups (64, 53 and 50 patients, respectively). Properly sized I-gel (No. 3-4) or LMA (No. 4-5) was inserted. We assessed haemodynamic data, airway leak pressure, leak volume, success rates and postoperative complications. There were no differences in the demographic data and haemodynamic data immediately after insertion of devices among the three groups. The airway leak pressures of the I-gel group (27.1 +/- 6.4 cmH2O) and pLMA group (29.8 +/- 5.7 cmH2O) were significantly higher than that of the cLMA group (24.7 +/- 6.2 cmH2O). The success rates for first attempt of insertion were similar among the three groups (P = 0.670). There were no differences in the incidence of adverse events except for the larger incidence of sore throat in the cLMA group. I-gel may have a similar airway sealing to that of pLMA, higher than that of cLMA, and is not associated with adverse events. The I-gel might be an effective alternative as a supraglottic airway device.

The I‐gel®, a single‐use supraglottic airway device with a non‐inflatable cuff and an esophageal vent: an observational study in children

The I-gel is a new single-use supraglottic airway device with a non-inflatable cuff. It is composed of a thermoplastic elastomer and a soft gel-like cuff that adapts to the hypopharyngeal anatomy. Like the LMA-ProSeal, it has an airway tube and a gastric drain tube. Little is known about its efficiency in pediatric anesthesia. Fifty children above 30 kg, ASA I-II, undergoing a short-duration surgery were included in this prospective, observational study. We evaluated ease in inserting the I-gel, seal pressure, gastric leak, complications during insertion and removal, ease in inserting the gastric tube and ventilatory parameters during positive pressure ventilation. All devices were inserted at the first attempt. The mean seal pressure was 25 cmH(2)O. There was no gastric inflation and gastric tube insertion was achieved in all cases. The results appear similar to those in a previous study concerning laryngeal mask airway in terms of leak pressure and complication rates. Because the I-gel has a very good insertion success rate and very few complications, it seems to be an efficient and safe device for pediatric airway management.

A New Single Use Supraglottic Airway Device with a Noninflatable Cuff and an Esophageal Vent: An Observational Study of the i-Gel

The i-gel is a new single-use supraglottic airway device with a noninflatable cuff and an esophageal vent. In this prospective, observational study, we evaluated the i-gel in 71 women. Insertion success rate was 97%. Insertion was easy and performed at the first attempt in every patient. Mean seal pressure was 30 +/- 7 cm H(2)O, and average peak pressure was 11 +/- 3 cm H(2)O. The gastric tube was inserted in 100% of cases. Only one case of coughing and one mild sore throat occurred. The i-gel is a reliable, easily inserted airway device that provides an adequate seal with a low morbidity rate.