Difficult Endotracheal Intubation
Conditions
Keywords
Intubation, Endotracheal, Endotracheal Intubation, adverse events
Brief summary
We propose to enroll 140 subjects scheduled for elective or urgent/emergent surgery with general anesthesia including endotracheal intubation. Patients qualify for the trial if they are considered a difficult airway case as determined by measurement of common predictive indices for difficult intubation (see inclusion criteria). All patients will be intubated with a GVL. Patients will be randomly assigned to either having their ETT placed with use of a pre-formed stylet provided by the manufacturer of the GVL (control group) or with a flexible, disposable tracheoscope (aScope, Ambu, Denmark) (intervention group). The randomization will be stratified as to whether patients are categorized as predicted difficult airway or have an immobilized cervical spine (C-collar in place).
Interventions
DEVICEaScope (Ambu Inc. 6740 Baymeadow Drive Glen Burnie, MD)
The aScope is a flexible, disposable plastic tracheoscope that incorporates a high-resolution video camera with an LED light at its flexible tip and has attached monitor.
DEVICEControl
pre-formed stylet provided by the manufacturer of the GlideScope® video laryngoscope
Sponsors
University of Louisville
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
SUPPORTIVE_CARE
Masking
SINGLE (Subject)
Eligibility
Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No
Inclusion criteria
* BMI \> 35 * Thyromental distance \< 6 cm * Sterno-mental distance \< 12 cm * Mallampati grade 3 and 4 * Interincisor distance \< 38 mm * Status of dentition: presence of buckteeth * Neck movement \< 35° * Neck circumference \>43 cm at the level of the thyroid cartilage * Patients with immobilized cervical spine (C-collar in place). * History of difficult laryngoscopy or intubation
Exclusion criteria
* Full stomach * Hiatal hernia * Severe GERD (Gastroesophageal reflux disease) * Tumors of the upper airway
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Intubation Time | 120 seconds | divided into time to successfully place the glidescope (visualization of the epiglottis), time to successfully insert the videostylet (passing through the cords) and time to verified placement of the ETT (as outlined above). Interim bag and mask time, if needed, will not be included in the intubation time. More than 5 attempts or 120 s are regarded as failure of intubation. If failure to secure the airway occurs with the GVL and videostylet, then conventional difficult intubation protocols approved by the University of Louisville Hospital will be implemented. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| The Number of Intubation Attempts | 30 minutes | counted as each approach of the ETT to the glottic entrance. |
| Neck Movement | 30 minutes | One observer will video-record the entire intubation procedure. At a later time, an otherwise unrelated observer will watch the video-records and grade the neck movement during intubation. Neck movement will be classified as Grade 0: no neck movement, Grade 1: minimal neck movement, or Grade 2: moderate neck movement. Results are reported as total with mild, moderate, or severe neck movement. |
| Laryngeal View Grade of 1 or 2 | 30 minutes | The laryngeal view as Grade 1 (full view of the glottis) or Grade 2 (glottis partly exposed, anterior commissure not seen) according to the method described by Cormack and Lehane (1984). |
| Ease of Intubation | 2-4 hours after intubation | After completion of the procedure the intubator will be asked to score the ease of intubation. To do this, he/she will give a score from 0-100 with 0 being the easiest and 100 being the hardest. |
Countries
United States
Participant flow
Participants by arm
| Arm | Count |
|---|---|
| Control Patients will be randomly assigned to having their ETT placed with use of a pre-formed stylet provided by the manufacturer of the GVL (control group)
Control: pre-formed stylet provided by the manufacturer of the GlideScope® video laryngoscope | 70 |
| Intervention Patients will be randomly assigned to either having their ETT placed with use of flexible, disposable tracheoscope (aScope, Ambu, Denmark) (intervention group).
aScope (Ambu Inc. 6740 Baymeadow Drive Glen Burnie, MD): The aScope is a flexible, disposable plastic tracheoscope that incorporates a high-resolution video camera with an LED light at its flexible tip and has attached monitor. | 70 |
| Total | 140 |
Baseline characteristics
| Characteristic | Control | Intervention | Total |
|---|---|---|---|
| Age, Continuous | 45 years STANDARD_DEVIATION 13 | 46 years STANDARD_DEVIATION 14 | 45 years STANDARD_DEVIATION 13 |
| Region of Enrollment United States | 70 participants | 70 participants | 140 participants |
| Sex: Female, Male Female | 37 Participants | 27 Participants | 64 Participants |
| Sex: Female, Male Male | 33 Participants | 43 Participants | 76 Participants |
Adverse events
| Event type | EG000 affected / at risk | EG001 affected / at risk |
|---|---|---|
| deaths Total, all-cause mortality | 0 / 70 | 0 / 70 |
| other Total, other adverse events | 0 / 70 | 0 / 70 |
| serious Total, serious adverse events | 2 / 70 | 2 / 70 |
Outcome results
Primary
Intubation Time
divided into time to successfully place the glidescope (visualization of the epiglottis), time to successfully insert the videostylet (passing through the cords) and time to verified placement of the ETT (as outlined above). Interim bag and mask time, if needed, will not be included in the intubation time. More than 5 attempts or 120 s are regarded as failure of intubation. If failure to secure the airway occurs with the GVL and videostylet, then conventional difficult intubation protocols approved by the University of Louisville Hospital will be implemented.
Time frame: 120 seconds
| Arm | Measure | Value (MEDIAN) |
|---|---|---|
| Control | Intubation Time | 66 time in seconds |
| Intervention | Intubation Time | 71 time in seconds |
p-value: <0.05Wilcoxon (Mann-Whitney)
Secondary
Ease of Intubation
After completion of the procedure the intubator will be asked to score the ease of intubation. To do this, he/she will give a score from 0-100 with 0 being the easiest and 100 being the hardest.
Time frame: 2-4 hours after intubation
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Control | Ease of Intubation | 36 units on a scale | Standard Deviation 23 |
| Intervention | Ease of Intubation | 39 units on a scale | Standard Deviation 25 |
p-value: 0.05Wilcoxon (Mann-Whitney)
Secondary
Laryngeal View Grade of 1 or 2
The laryngeal view as Grade 1 (full view of the glottis) or Grade 2 (glottis partly exposed, anterior commissure not seen) according to the method described by Cormack and Lehane (1984).
Time frame: 30 minutes
| Arm | Measure | Value (COUNT_OF_PARTICIPANTS) |
|---|---|---|
| Control | Laryngeal View Grade of 1 or 2 | 62 Participants |
| Intervention | Laryngeal View Grade of 1 or 2 | 50 Participants |
p-value: 0.05Chi-squared
Secondary
Neck Movement
One observer will video-record the entire intubation procedure. At a later time, an otherwise unrelated observer will watch the video-records and grade the neck movement during intubation. Neck movement will be classified as Grade 0: no neck movement, Grade 1: minimal neck movement, or Grade 2: moderate neck movement. Results are reported as total with mild, moderate, or severe neck movement.
Time frame: 30 minutes
Population: Only those participants with available data were analyzed for the assessment. All subjects reported had mild, moderate or severe neck movement.
| Arm | Measure | Value (COUNT_OF_PARTICIPANTS) |
|---|---|---|
| Control | Neck Movement | 47 Participants |
| Intervention | Neck Movement | 54 Participants |
p-value: 0.05Chi-squared
Secondary
The Number of Intubation Attempts
counted as each approach of the ETT to the glottic entrance.
Time frame: 30 minutes
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Control | The Number of Intubation Attempts | 1.2 Number of intubation attempts | Standard Deviation 0.6 |
| Intervention | The Number of Intubation Attempts | 1.1 Number of intubation attempts | Standard Deviation 0.4 |
p-value: <0.05Wilcoxon (Mann-Whitney)