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Comparison of I-gel to the Laryngeal Mask Airway

A Randomized Clinical Comparison of the Intersurgical I-gel and the Laryngeal Mask Airway Unique in Non-Obese Adult Patients During General Surgery

Status
Completed
Phases
NA
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT00706823
Acronym
I-gel
Enrollment
50
Registered
2008-06-30
Start date
2008-02-29
Completion date
2008-08-31
Last updated
2017-02-20

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Endotracheal Intubation, Supraglottic Airway

Keywords

Endotracheal Intubation, Supraglottic Airway

Brief summary

The purpose of this study is to evaluate a new disposable supra-glottic airway device, the i-gel airway (Intersurgical Ltd., Wokingham, England). We propose to test its ease of insertion, position within the airway, drain tube patency and anatomic sealing properties during mechanical ventilation in non-obese anesthetized patients undergoing elective general surgery. The study device will be compared to the current standard in the industry, the LMA Unique.

Detailed description

During the past decade, several pharyngeal airways have been introduced for airway management, such as the Laryngeal Mask Airway (LMA), the Cobra perilaryngeal airway, the Esophageal Tracheal Combitube (ETC), the EasyTube, the Laryngeal Tube6, and the Streamlined Liner of the Pharyngeal Airway (SLIPA). These airway devices have become very popular because of their ability to maintain an airway without perturbing the trachea and can be used in patients without muscle relaxation who are only lightly anesthetized. The LMA Classic (cLMA) generally provides an adequate airway, but certain problems remain: 1. In 8-33% of LMA placements, more than one attempt is required. 2. It is sometimes difficult to advance the LMA without extending the neck (which is contraindicated in some patients). 3. The device does not protect the airway from aspiration of gastric contents. 4. It does not provide an airtight seal around the larynx (the usual pressures causing leakage of gas being 15-20 cm H20). Consequently, the device may function poorly during positive-pressure ventilation. 5. The esophagus is included within the rim of the LMA in 10-15% of patients, directly exposing the esophagus to positive airway pressures. This often results in insufflation of the stomach and postoperative discomfort. The LMA Unique (uLMA) is a disposable, inflatable supraglottic airway device that is based on the LMA Classic design which has been used as the model in the industry. It has been listed as a commonly accepted device for routine and rescue airway management and is now listed in the American Society of Anesthesiologists (ASA) Difficult Airway Management Algorithm as an airway conduit for tracheal intubation. The i-gel (Intersurgical Ltd., Wokingham, England) is a cuffless, single-use supraglottic airway device designed to provide a more effective seal than the uLMA, thus eliminating problems 3-5 described above with the addition of a gastric drain. Made of a gel-like thermoplastic elastomer, the i-gel has an anatomically-designed mask that allows quick, easy insertion and can accurately position itself over the laryngeal framework to provide a reliable perilaryngeal seal without the need for an inflatable cuff. In a preliminary study, the peak airway pressures were found to be above 30 cm H2O with a sustained leak pressure of 24 cm H2O versus an average of 18-21 cm H2O seen with the cLMA. According to the 100 patient trial, the i-gel is easier to insert, it has better sealing properties and there is no cuffed inflates. This clinical study has been designed to compare the i-gel and the uLMA, as to ease of placement, ventilation during mechanical ventilation, proper positioning, seal pressures, the patency of the drain tube, and finally, any complications with their use. Fiberoptic observations through each device will provide information in relation to the epiglottis and the distal opening of the device.

Interventions

DEVICELaryngeal Mask Airway-Unique

supra-glottic airway device

Sponsors

The University of Texas Health Science Center, Houston
Lead SponsorOTHER

Study design

Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
SINGLE (Subject)

Eligibility

Sex/Gender
ALL
Age
18 Years to 80 Years
Healthy volunteers
Yes

Inclusion criteria

1. The subjects will be adult surgical candidates aged 18-80, ASA I-II, Mallampati I or II, presenting for elective surgery who require general anesthesia in whom tracheal intubation is not necessary. 2. Both male and female patients will be included.

Exclusion criteria

Patients will be excluded from the study if they present as Mallampati III or IV, ASA III-V or emergency status. Additionally, they will be excluded if they meet one of the contraindication criteria of the LMA including: 1. obesity, (BMI \> 35 kg/m2) 2. pregnancy 3. history of gastric regurgitation, heart burn, ileus or full stomach 4. history of low pulmonary compliance or high pulmonary resistance 5. known history of difficult endotracheal intubation or signs suggesting the possibility of difficult intubation 6. pharyngeal pathology 7. upper airway obstruction due to laryngeal pathology

Design outcomes

Primary

MeasureTime frameDescription
Time Required for Intubationduration of intubationThe total time to intubation was measured from the beginning of supraglottic airway device (SGA) insertion to successful endotracheal tube intubation, verified by detection of CO2 on the capnogram (anesthesia machine).
Leak Pressureduration of intubationAfter successful placement, airway leak pressure was assessed by closing the circuit to atmosphere and allowing fresh gas flow to build airway pressure. The pressure at which an audible leak was heard was recorded; airway pressure was not permitted to exceed 40 cm H2O.

Secondary

MeasureTime frameDescription
Level of Difficulty for Intubationduration of intubationEase of SGA insertion and intubation was subjectively assessed by the operator on a scale from 1 to 5 (1 = very easy, 2 = easy, 3 = neutral, 4 = difficult, 5 = very difficult).
Number of Participants With Oropharyngeal Discomfortpost operative, immediately and 24 hrs after intubationOropharyngeal discomfort was assessed. including sore throat, hoarseness, and dysphagia.
Number of Participants With Successful Gastric Drainage Tube Placement as Assessed by Fiberoptic Scope Visualizationafter intubationWhen the fiberoptic scope was placed in the gastirc drain tube of the i-gel, if the esophageal mucosa was visible and the stomach was readily accessible, then placement was considered succussful.
Number of AttemptsBefore intubationThe number of attempts taken to place the device

Countries

United States

Participant flow

Recruitment details

The patients for this study have been recruited from Feb 2008 through July 2008. The patients were recruited from the day surgery and holding areas.

Participants by arm

ArmCount
I-gel-SGA
Patients who received i-gel SGA for intubation
25
LMA-Unique
Patients who received LMA-Unique for intubation
25
Total50

Baseline characteristics

CharacteristicLMA-UniqueI-gel-SGATotal
Age, Categorical
<=18 years
1 Participants0 Participants1 Participants
Age, Categorical
>=65 years
1 Participants0 Participants1 Participants
Age, Categorical
Between 18 and 65 years
23 Participants25 Participants48 Participants
Age, Continuous35.3 years
STANDARD_DEVIATION 16.6
38.2 years
STANDARD_DEVIATION 10.5
37.28 years
STANDARD_DEVIATION 13.8
Gender
Female
6 Participants9 Participants15 Participants
Gender
Male
19 Participants16 Participants35 Participants
Region of Enrollment
United States
25 participants25 participants50 participants

Adverse events

Event typeEG000
affected / at risk
EG001
affected / at risk
deaths
Total, all-cause mortality
— / —— / —
other
Total, other adverse events
6 / 2510 / 25
serious
Total, serious adverse events
0 / 250 / 25

Outcome results

Primary

Leak Pressure

After successful placement, airway leak pressure was assessed by closing the circuit to atmosphere and allowing fresh gas flow to build airway pressure. The pressure at which an audible leak was heard was recorded; airway pressure was not permitted to exceed 40 cm H2O.

Time frame: duration of intubation

ArmMeasureValue (MEAN)Dispersion
I-gel-SGALeak Pressure23.08 cm of H2OStandard Deviation 7.3
LMA-UniqueLeak Pressure20.88 cm of H2OStandard Deviation 4.5
p-value: 0.22t-test, 2 sided
Primary

Time Required for Intubation

The total time to intubation was measured from the beginning of supraglottic airway device (SGA) insertion to successful endotracheal tube intubation, verified by detection of CO2 on the capnogram (anesthesia machine).

Time frame: duration of intubation

ArmMeasureValue (MEAN)Dispersion
I-gel-SGATime Required for Intubation21.04 secondsStandard Deviation 12.6
LMA-UniqueTime Required for Intubation30.04 secondsStandard Deviation 14.1
p-value: 0.02t-test, 2 sided
Secondary

Level of Difficulty for Intubation

Ease of SGA insertion and intubation was subjectively assessed by the operator on a scale from 1 to 5 (1 = very easy, 2 = easy, 3 = neutral, 4 = difficult, 5 = very difficult).

Time frame: duration of intubation

ArmMeasureGroupValue (NUMBER)
I-gel-SGALevel of Difficulty for IntubationEasy12 participants
I-gel-SGALevel of Difficulty for IntubationDifficult2 participants
I-gel-SGALevel of Difficulty for IntubationNeutral0 participants
I-gel-SGALevel of Difficulty for IntubationVery Difficult0 participants
I-gel-SGALevel of Difficulty for IntubationVery Easy11 participants
LMA-UniqueLevel of Difficulty for IntubationVery Difficult0 participants
LMA-UniqueLevel of Difficulty for IntubationVery Easy8 participants
LMA-UniqueLevel of Difficulty for IntubationEasy17 participants
LMA-UniqueLevel of Difficulty for IntubationNeutral0 participants
LMA-UniqueLevel of Difficulty for IntubationDifficult0 participants
p-value: 0.22Fisher Exact
Secondary

Number of Attempts

The number of attempts taken to place the device

Time frame: Before intubation

ArmMeasureGroupValue (NUMBER)
I-gel-SGANumber of Attempts1 attempt17 participants
I-gel-SGANumber of Attempts2 attempts7 participants
I-gel-SGANumber of Attempts3 attempts1 participants
LMA-UniqueNumber of Attempts1 attempt21 participants
LMA-UniqueNumber of Attempts2 attempts3 participants
LMA-UniqueNumber of Attempts3 attempts1 participants
p-value: 0.0395% CI: [1.1, 58.6]Regression, Logistic
Secondary

Number of Participants With Oropharyngeal Discomfort

Oropharyngeal discomfort was assessed. including sore throat, hoarseness, and dysphagia.

Time frame: post operative, immediately and 24 hrs after intubation

ArmMeasureGroupValue (NUMBER)
I-gel-SGANumber of Participants With Oropharyngeal DiscomfortPostop symptoms present6 participants
I-gel-SGANumber of Participants With Oropharyngeal DiscomfortPostop symptoms absent19 participants
LMA-UniqueNumber of Participants With Oropharyngeal DiscomfortPostop symptoms present10 participants
LMA-UniqueNumber of Participants With Oropharyngeal DiscomfortPostop symptoms absent15 participants
Secondary

Number of Participants With Successful Gastric Drainage Tube Placement as Assessed by Fiberoptic Scope Visualization

When the fiberoptic scope was placed in the gastirc drain tube of the i-gel, if the esophageal mucosa was visible and the stomach was readily accessible, then placement was considered succussful.

Time frame: after intubation

Population: Only the -gel has a gastric drainage tube--the uLMA does not. Thus, only those receiving the i-gel were assessed for this measure.

ArmMeasureGroupValue (NUMBER)
I-gel-SGANumber of Participants With Successful Gastric Drainage Tube Placement as Assessed by Fiberoptic Scope VisualizationEsophageal mucosa visible and stomach accessible22 participants
I-gel-SGANumber of Participants With Successful Gastric Drainage Tube Placement as Assessed by Fiberoptic Scope VisualizationUpper esophageal sphincter visible2 participants
I-gel-SGANumber of Participants With Successful Gastric Drainage Tube Placement as Assessed by Fiberoptic Scope VisualizationGlottis visible1 participants

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026