Intubation, Laryngoscopy
Conditions
Keywords
endotracheal intubation, intubation, laryngoscopy, laryngoscope, surgery
Brief summary
The placement of endotracheal tubes (intubation) is a physiologically stressful procedure for patients. Laryngoscopes are devices-typically composed of a blade attached to a handle with a light source-that allow examination of the upper airway through the mouth, often for the purposes of intubation. Recently some new laryngoscope devices (including the Airtraq® Optical Laryngoscope, the Storz DCI Video laryngoscope®, McGRATH® Video Laryngoscope, and the GlideScope®) have been developed, which may either decrease the stress related to intubation (reduce neck extension, reduce risk of complications or reduce time elapsed during intubation) or improve intubation success (reduce the number of attempts at intubating). Data are being collected in this study to determine which of these commonly-used devices may be better, particularly in comparison to the current hospital standard, the Macintosh laryngoscope. All of the devices to be used in this study are currently cleared or exempt by the Food and Drug Administration (FDA).
Detailed description
Historically, optical and video laryngoscopes have been used as alternative airway management devices for the difficult airway, and as rescue devices. Their use by experienced laryngoscopists has not been compared in a prospective, randomized, head-to-head comparison for routine airway management in adult surgical patients. Video and optical laryngoscopes have been developed to improve the laryngeal view for tracheal intubation and to decrease physiological stress associated with the procedure. The objective of this study is to determine whether these devices offer superior intubating conditions for routine surgical management, over the Macintosh laryngoscope, which is the current standard. The devices to be compared in this study are the most commonly used video and optical laryngoscopes on the market and are cleared or exempt by the Food and Drug Administration (FDA). Eligible subjects include elective adult surgical patients with an ASA status between 1 and 3 requiring general endotracheal anesthesia. Subjects with a BMI ≥ 40, or undergoing surgery in close proximity to the neck will be excluded. Prior to surgery, subjects will receive a pre-anesthesia evaluation with particular attention to the airway using the Mallampati classification system; atlanto-occipital joint extension; thyro-mental distance; temporomandibular joint function; inter-incisor distance; and dental assessment. Subjects will be randomized for intubation with one of the five laryngoscopes in equal proportions. The following data were recorded: total intubation time, maximum neck extension using an angle gauge, glottic view, assessed by the anesthesiologist using the Cook modification of the Cormack-Lehane grading system (Figure 1), and ease of tracheal intubation using a 5-point rating scale; 5 (excellent) to 1 (poor). Subjects were queried about soreness or painful swallowing in the PACU and a week later via a phone call.
Interventions
Used during laryngoscopy to facilitate intubation.
Used during laryngoscopy to facilitate intubation.
Used during laryngoscopy to facilitate intubation
Used during laryngoscopy to facilitate intubation
Used during laryngoscopy to facilitate intubation
Sponsors
Study design
Eligibility
Inclusion criteria
* Elective adult surgical patient requiring general endotracheal anesthesia. * Males and Females. * ASA Physical Status 1-3. * Age 18 years of age and older
Exclusion criteria
* Body Mass Index (BMI) ≥35kg/m2. * If subject is of childbearing potential, a positive pregnancy test at the time of study enrollment. * Has physical, mental, or medical conditions which, in the opinion of the Investigator, could compromise the subject's welfare, ability to communicate with the study staff, complete study activities, or would otherwise contraindicate study participation. * Intubated prior to surgery. * Severe cardiovascular, hepatic or renal disease. * Need for nasal intubation. * An investigator of this study. * Inclusion in another clinical research study. * Subject's refusal or inability to agree to and to sign the Informed Consent Form in English. * Subject requiring awake airway management.
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Percentage Distribution of Cook's Modification of Cormack-Lehane's Grading System. Each Study Subject Will Receive a Grade of 1, 2A, 2B, 3A, 3B, or 4 in the Cormack-Lehane Grading System. | 1 time during laryngoscopy | Percentage distribution of Cook's modification of Cormack-Lehane's grading system. This is a classification that records the best laryngeal view obtained with or without anterior laryngeal pressure. Each study subject will receive a grade of 1, 2A, 2B, 3A, 3B, or 4 in the Cormack-Lehane grading system. Grades 1 and 2A classify as an easy view: when the laryngeal inlet is visible. Grades 2B and 3A classify as restricted: when the posterior glottic structures are visible or the epiglottis is visible and can be lifted. Grades 3B and 4 classify as difficult: when the epiglottis cannot be lifted or when no laryngeal structures are visible. Cook's modification of Cormack-Lehane's Grades 1=1, 2=2A,3=2B, 4=3A, 5=3B, 6=4. |
Participant flow
Participants by arm
| Arm | Count |
|---|---|
| Macintosh Laryngoscope Macintosh laryngoscope (control group/direct laryngoscopy) - current standard
Macintosh laryngoscope: Used during laryngoscopy to facilitate intubation. | 48 |
| Airtraq Optical Laryngoscope Airtraq® Optical Laryngoscope (an experimental group/indirect laryngoscopy)
Airtraq® Optical Laryngoscope: Used during laryngoscopy to facilitate intubation. | 48 |
| Storz DCI Video Laryngoscope Storz DCI Video Laryngoscope® (an experimental group/indirect laryngoscopy)
Storz DCI Video Laryngoscope®: Used during laryngoscopy to facilitate intubation | 48 |
| GlideScope Video Laryngoscope GlideScope® Video Laryngoscope (an experimental group/indirect laryngoscopy)
GlideScope® Video Laryngoscope: Used during laryngoscopy to facilitate intubation | 48 |
| McGRATH Video Laryngoscope McGRATH® Video Laryngoscope (an experimental group/indirect laryngoscopy)
McGRATH® Video Laryngoscope: Used during laryngoscopy to facilitate intubation | 48 |
| Total | 240 |
Withdrawals & dropouts
| Period | Reason | FG000 | FG001 | FG002 | FG003 | FG004 |
|---|---|---|---|---|---|---|
| Overall Study | Failed Intubation | 0 | 1 | 0 | 1 | 0 |
| Overall Study | Lost to Follow-up | 3 | 2 | 3 | 2 | 3 |
Baseline characteristics
| Characteristic | Total | Macintosh Laryngoscope | Airtraq Optical Laryngoscope | Storz DCI Video Laryngoscope | GlideScope Video Laryngoscope | McGRATH Video Laryngoscope |
|---|---|---|---|---|---|---|
| Age, Continuous | 48.7 years STANDARD_DEVIATION 15.4 | 50.3 years STANDARD_DEVIATION 16.9 | 46.1 years STANDARD_DEVIATION 13.5 | 47.8 years STANDARD_DEVIATION 15.4 | 50.0 years STANDARD_DEVIATION 15.2 | 49.3 years STANDARD_DEVIATION 15.8 |
| Sex: Female, Male Female | 114 Participants | 20 Participants | 25 Participants | 21 Participants | 25 Participants | 23 Participants |
| Sex: Female, Male Male | 126 Participants | 28 Participants | 23 Participants | 27 Participants | 23 Participants | 25 Participants |
Adverse events
| Event type | EG000 affected / at risk | EG001 affected / at risk | EG002 affected / at risk | EG003 affected / at risk | EG004 affected / at risk |
|---|---|---|---|---|---|
| deaths Total, all-cause mortality | 0 / 48 | 0 / 48 | 0 / 48 | 0 / 48 | 0 / 48 |
| other Total, other adverse events | 0 / 48 | 0 / 48 | 0 / 48 | 0 / 48 | 1 / 48 |
| serious Total, serious adverse events | 2 / 48 | 0 / 48 | 0 / 48 | 0 / 48 | 1 / 48 |
Outcome results
Percentage Distribution of Cook's Modification of Cormack-Lehane's Grading System. Each Study Subject Will Receive a Grade of 1, 2A, 2B, 3A, 3B, or 4 in the Cormack-Lehane Grading System.
Percentage distribution of Cook's modification of Cormack-Lehane's grading system. This is a classification that records the best laryngeal view obtained with or without anterior laryngeal pressure. Each study subject will receive a grade of 1, 2A, 2B, 3A, 3B, or 4 in the Cormack-Lehane grading system. Grades 1 and 2A classify as an easy view: when the laryngeal inlet is visible. Grades 2B and 3A classify as restricted: when the posterior glottic structures are visible or the epiglottis is visible and can be lifted. Grades 3B and 4 classify as difficult: when the epiglottis cannot be lifted or when no laryngeal structures are visible. Cook's modification of Cormack-Lehane's Grades 1=1, 2=2A,3=2B, 4=3A, 5=3B, 6=4.
Time frame: 1 time during laryngoscopy
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Macintosh Laryngoscope | Percentage Distribution of Cook's Modification of Cormack-Lehane's Grading System. Each Study Subject Will Receive a Grade of 1, 2A, 2B, 3A, 3B, or 4 in the Cormack-Lehane Grading System. | 1.98 units on a scale | Standard Deviation 1.96 |
| Airtraq Optical Laryngoscope | Percentage Distribution of Cook's Modification of Cormack-Lehane's Grading System. Each Study Subject Will Receive a Grade of 1, 2A, 2B, 3A, 3B, or 4 in the Cormack-Lehane Grading System. | 1.18 units on a scale | Standard Deviation 0.44 |
| Storz DCI Video Laryngoscope | Percentage Distribution of Cook's Modification of Cormack-Lehane's Grading System. Each Study Subject Will Receive a Grade of 1, 2A, 2B, 3A, 3B, or 4 in the Cormack-Lehane Grading System. | 1.27 units on a scale | Standard Deviation 0.54 |
| GlideScope Video Laryngoscope | Percentage Distribution of Cook's Modification of Cormack-Lehane's Grading System. Each Study Subject Will Receive a Grade of 1, 2A, 2B, 3A, 3B, or 4 in the Cormack-Lehane Grading System. | 1.47 units on a scale | Standard Deviation 0.59 |
| McGRATH Video Laryngoscope | Percentage Distribution of Cook's Modification of Cormack-Lehane's Grading System. Each Study Subject Will Receive a Grade of 1, 2A, 2B, 3A, 3B, or 4 in the Cormack-Lehane Grading System. | 1.13 units on a scale | Standard Deviation 0.34 |