Trial Outcomes & Findings for McGRATH MAC Video Laryngoscope (NCT NCT02250521)

NCT ID: NCT02250521

Last Updated: 2018-11-09

Results Overview

All 100 patients will be intubated using the McGRATH® MAC video laryngoscope, either through direct or indirect vision laryngoscopy. The LCD monitor of the McGRATH™ MAC was initially covered; if the anesthesiologist visualized a modified C-L grade 1-3 view, the patient was intubated utilizing this direct view. If the anesthesiologist observed a modified C-L grade 4 view during their initial direct view, the patient was intubated using the indirect method. If intubation via direct laryngoscopy was unsuccessful on the first attempt, the patient was intubated using the indirect view. If both methods of laryngoscopy were unsuccessful, the rescue intubation technique was performed at the discretion of the anesthesiologist.

• Recruitment status: COMPLETED
• Study phase: NA
• Target enrollment: 100 participants
• Primary outcome timeframe: after successful endotracheal tube placement
• Results posted on: 2018-11-09

Participant Flow

Participant milestones

Measure	McGrath Mac Intubations All 100 patients will be intubated using the McGRATH® MAC video laryngoscope, either through direct or indirect vision laryngoscopy. The liquid crystal display (LCD) monitor of the McGRATH™ MAC was initially covered; if the anesthesiologist visualized a modified C-L grade 1-3 view, the patient was intubated utilizing this direct view. If the anesthesiologist observed a modified C-L grade 4 view during their initial direct view, the patient was intubated using the indirect method. If intubation via direct laryngoscopy was unsuccessful on the first attempt, the patient was intubated using the indirect view. If both methods of laryngoscopy were unsuccessful, the rescue intubation technique was performed at the discretion of the anesthesiologist.
Overall Study STARTED	100
Overall Study COMPLETED	99
Overall Study NOT COMPLETED	1

Reasons for withdrawal

Withdrawal data not reported

Baseline Characteristics

Of the 100 patients recruited, 6 patients were excluded from data analysis. 4 patients were found to not meet inclusion criteria. One patient with glottic view grade 3 was erroneously intubated via the indirect method. For another patient, the anesthesiologist aborted the protocol due to encountered difficulties.

Baseline characteristics by cohort

Measure	McGrath Mac Intubations n=100 Participants All 100 patients will be intubated using the McGRATH® MAC video laryngoscope, either through direct or indirect vision laryngoscopy. The LCD monitor of the McGRATH™ MAC was initially covered; if the anesthesiologist visualized a modified C-L grade 1-3 view, the patient was intubated utilizing this direct view. If the anesthesiologist observed a modified C-L grade 4 view during their initial direct view, the patient was intubated using the indirect method. If intubation via direct laryngoscopy was unsuccessful on the first attempt, the patient was intubated using the indirect view. If both methods of laryngoscopy were unsuccessful, the rescue intubation technique was performed at the discretion of the anesthesiologist.
Age, Continuous	53.17 years STANDARD_DEVIATION 14.70 • n=94 Participants • Of the 100 patients recruited, 6 patients were excluded from data analysis. 4 patients were found to not meet inclusion criteria. One patient with glottic view grade 3 was erroneously intubated via the indirect method. For another patient, the anesthesiologist aborted the protocol due to encountered difficulties.
Sex: Female, Male Female	40 Participants n=100 Participants
Sex: Female, Male Male	60 Participants n=100 Participants

PRIMARY outcome

Timeframe: after successful endotracheal tube placement

Population: Of the 100 patients recruited, 6 patients were excluded from data analysis. 4 patients were found to not meet inclusion criteria. One patient with glottic view grade 3 was erroneously intubated via the indirect method. For another patient, the anesthesiologist aborted the protocol due to encountered difficulties.

All 100 patients will be intubated using the McGRATH® MAC video laryngoscope, either through direct or indirect vision laryngoscopy. The LCD monitor of the McGRATH™ MAC was initially covered; if the anesthesiologist visualized a modified C-L grade 1-3 view, the patient was intubated utilizing this direct view. If the anesthesiologist observed a modified C-L grade 4 view during their initial direct view, the patient was intubated using the indirect method. If intubation via direct laryngoscopy was unsuccessful on the first attempt, the patient was intubated using the indirect view. If both methods of laryngoscopy were unsuccessful, the rescue intubation technique was performed at the discretion of the anesthesiologist.

Outcome measures

Measure	McGrath Mac Intubations n=94 Participants All 100 patients will be intubated using the McGRATH® MAC video laryngoscope, either through direct or indirect vision laryngoscopy. The LCD monitor of the McGRATH™ MAC was initially covered; if the anesthesiologist visualized a modified C-L grade 1-3 view, the patient was intubated utilizing this direct view. If the anesthesiologist observed a modified C-L grade 4 view during their initial direct view, the patient was intubated using the indirect method. If intubation via direct laryngoscopy was unsuccessful on the first attempt, the patient was intubated using the indirect view. If both methods of laryngoscopy were unsuccessful, the rescue intubation technique was performed at the discretion of the anesthesiologist.
Number of Participants Successfully Intubated on First Attempt With Use of Either a Direct or Indirect Laryngoscopic View direct laryngoscopic view	72 Participants
Number of Participants Successfully Intubated on First Attempt With Use of Either a Direct or Indirect Laryngoscopic View indirect laryngoscopic view	16 Participants

SECONDARY outcome

Timeframe: at the time of laryngoscopy

Population: Of the 100 patients recruited, 6 patients were excluded from data analysis. 4 patients were found to not meet inclusion criteria. One patient with glottic view grade 3 was erroneously intubated via the indirect method. For another patient, the anesthesiologist aborted the protocol due to encountered difficulties.

Glottic view as described by Cormack and Lehane, scored as follows- Grade 1. Full view of glottis Grade 2a. Partial view of glottis Grade 2b. Arytenoids or posterior portion of cords just visible Grade 3. Only the epiglottis visible Grade 4. Neither epiglottis nor glottis visible

Outcome measures

Measure	McGrath Mac Intubations n=94 Participants All 100 patients will be intubated using the McGRATH® MAC video laryngoscope, either through direct or indirect vision laryngoscopy. The LCD monitor of the McGRATH™ MAC was initially covered; if the anesthesiologist visualized a modified C-L grade 1-3 view, the patient was intubated utilizing this direct view. If the anesthesiologist observed a modified C-L grade 4 view during their initial direct view, the patient was intubated using the indirect method. If intubation via direct laryngoscopy was unsuccessful on the first attempt, the patient was intubated using the indirect view. If both methods of laryngoscopy were unsuccessful, the rescue intubation technique was performed at the discretion of the anesthesiologist.
Glottic View With Direct Laryngoscopy Grade 1 view	11 Participants
Glottic View With Direct Laryngoscopy Grade 2a view	18 Participants
Glottic View With Direct Laryngoscopy Grade 2b view	27 Participants
Glottic View With Direct Laryngoscopy Grade 3 view	21 Participants
Glottic View With Direct Laryngoscopy Grade 4 view	17 Participants

SECONDARY outcome

Timeframe: at the time of laryngoscopy

Population: Of the 100 patients recruited, 6 patients were excluded from data analysis. 4 patients were found to not meet inclusion criteria. One patient with glottic view grade 3 was erroneously intubated via the indirect method. For another patient, the anesthesiologist aborted the protocol due to encountered difficulties.

Glottic view as described by Cormack and Lehane (Samsoon GL, Young JR. Difficult tracheal intubation: A retrospective study. Anesthesia 1987; 42:487), scored as follows- Grade 1. Full view of glottis Grade 2a. Partial view of glottis Grade 2b. Arytenoids or posterior portion of cords just visible Grade 3. Only the epiglottis visible Grade 4. Neither epiglottis nor glottis visible

Outcome measures

Measure	McGrath Mac Intubations n=94 Participants All 100 patients will be intubated using the McGRATH® MAC video laryngoscope, either through direct or indirect vision laryngoscopy. The LCD monitor of the McGRATH™ MAC was initially covered; if the anesthesiologist visualized a modified C-L grade 1-3 view, the patient was intubated utilizing this direct view. If the anesthesiologist observed a modified C-L grade 4 view during their initial direct view, the patient was intubated using the indirect method. If intubation via direct laryngoscopy was unsuccessful on the first attempt, the patient was intubated using the indirect view. If both methods of laryngoscopy were unsuccessful, the rescue intubation technique was performed at the discretion of the anesthesiologist.
Glottic View With Indirect Laryngoscopy Grade 1 view	51 Participants
Glottic View With Indirect Laryngoscopy Grade 2b view	17 Participants
Glottic View With Indirect Laryngoscopy Grade 2a view	16 Participants
Glottic View With Indirect Laryngoscopy Grade 3 view	6 Participants
Glottic View With Indirect Laryngoscopy Grade 4 view	4 Participants

SECONDARY outcome

Timeframe: at the time of laryngoscopy

Population: Of the 100 patients recruited, 6 patients were excluded from data analysis, as describe in Outcome Measure 1's Analysis Population Description. 78 of the 94 analyzed had direct laryngoscopy, and thus 78 are analyzed in this outcome measure.

Time from mouth opening to best direct laryngoscopic view

Outcome measures

Measure

McGrath Mac Intubations n=78 Participants All 100 patients will be intubated using the McGRATH® MAC video laryngoscope, either through direct or indirect vision laryngoscopy. The LCD monitor of the McGRATH™ MAC was initially covered; if the anesthesiologist visualized a modified C-L grade 1-3 view, the patient was intubated utilizing this direct view. If the anesthesiologist observed a modified C-L grade 4 view during their initial direct view, the patient was intubated using the indirect method. If intubation via direct laryngoscopy was unsuccessful on the first attempt, the patient was intubated using the indirect view. If both methods of laryngoscopy were unsuccessful, the rescue intubation technique was performed at the discretion of the anesthesiologist.

Time for Direct View Laryngoscopy During the First Attempt

12.41 seconds Standard Deviation 7.13

SECONDARY outcome

Timeframe: at the time of laryngoscopy

Population: Of the 100 patients recruited, 6 patients were excluded from data analysis, as describe in Outcome Measure 1's Analysis Population Description. 16 of the 94 analyzed had direct laryngoscopy, and thus 16 are analyzed in this outcome measure.

Time from mouth opening to best indirect laryngoscopic view

Outcome measures

Measure

McGrath Mac Intubations n=16 Participants All 100 patients will be intubated using the McGRATH® MAC video laryngoscope, either through direct or indirect vision laryngoscopy. The LCD monitor of the McGRATH™ MAC was initially covered; if the anesthesiologist visualized a modified C-L grade 1-3 view, the patient was intubated utilizing this direct view. If the anesthesiologist observed a modified C-L grade 4 view during their initial direct view, the patient was intubated using the indirect method. If intubation via direct laryngoscopy was unsuccessful on the first attempt, the patient was intubated using the indirect view. If both methods of laryngoscopy were unsuccessful, the rescue intubation technique was performed at the discretion of the anesthesiologist.

Time for Indirect View Laryngoscopy During the First Attempt

14.73 seconds Standard Deviation 9.99

SECONDARY outcome

Timeframe: at the time of laryngoscopy

Population: Of the 100 patients recruited, 6 patients were excluded from data analysis. 4 patients were found to not meet inclusion criteria. One patient with glottic view grade 3 was erroneously intubated via the indirect method. For another patient, the anesthesiologist aborted the protocol due to encountered difficulties.

Time for laryngoscopy (either direct or indirect) plus the time for endotracheal tube (ETT) cuff to pass vocal cords.

Outcome measures

Measure

McGrath Mac Intubations n=94 Participants All 100 patients will be intubated using the McGRATH® MAC video laryngoscope, either through direct or indirect vision laryngoscopy. The LCD monitor of the McGRATH™ MAC was initially covered; if the anesthesiologist visualized a modified C-L grade 1-3 view, the patient was intubated utilizing this direct view. If the anesthesiologist observed a modified C-L grade 4 view during their initial direct view, the patient was intubated using the indirect method. If intubation via direct laryngoscopy was unsuccessful on the first attempt, the patient was intubated using the indirect view. If both methods of laryngoscopy were unsuccessful, the rescue intubation technique was performed at the discretion of the anesthesiologist.

Time for Intubation

35.91 seconds Standard Deviation 22.66

SECONDARY outcome

Timeframe: at the time of intubation

Population: Of the 100 patients recruited, 6 patients were excluded from data analysis. 4 patients were found to not meet inclusion criteria. One patient with glottic view grade 3 was erroneously intubated via the indirect method. For another patient, the anesthesiologist aborted the protocol due to encountered difficulties.

Outcome measures

Measure	McGrath Mac Intubations n=94 Participants All 100 patients will be intubated using the McGRATH® MAC video laryngoscope, either through direct or indirect vision laryngoscopy. The LCD monitor of the McGRATH™ MAC was initially covered; if the anesthesiologist visualized a modified C-L grade 1-3 view, the patient was intubated utilizing this direct view. If the anesthesiologist observed a modified C-L grade 4 view during their initial direct view, the patient was intubated using the indirect method. If intubation via direct laryngoscopy was unsuccessful on the first attempt, the patient was intubated using the indirect view. If both methods of laryngoscopy were unsuccessful, the rescue intubation technique was performed at the discretion of the anesthesiologist.
Number of Intubation Attempts 1 attempt	88 Participants
Number of Intubation Attempts 2 attempts	5 Participants
Number of Intubation Attempts 3 attempts	1 Participants

SECONDARY outcome

Timeframe: at the time of intubation

Population: Of the 100 patients recruited, 6 patients were excluded from data analysis. 4 patients were found to not meet inclusion criteria. One patient with glottic view grade 3 was erroneously intubated via the indirect method. For another patient, the anesthesiologist aborted the protocol due to encountered difficulties.

Outcome measures

Measure

McGrath Mac Intubations n=94 Participants All 100 patients will be intubated using the McGRATH® MAC video laryngoscope, either through direct or indirect vision laryngoscopy. The LCD monitor of the McGRATH™ MAC was initially covered; if the anesthesiologist visualized a modified C-L grade 1-3 view, the patient was intubated utilizing this direct view. If the anesthesiologist observed a modified C-L grade 4 view during their initial direct view, the patient was intubated using the indirect method. If intubation via direct laryngoscopy was unsuccessful on the first attempt, the patient was intubated using the indirect view. If both methods of laryngoscopy were unsuccessful, the rescue intubation technique was performed at the discretion of the anesthesiologist.

Number of Participants Who Received External Laryngeal Manipulation During the First Attempt

42 Participants

SECONDARY outcome

Timeframe: at the time of intubation

Population: Of the 100 patients recruited, 6 patients were excluded from data analysis. 4 patients were found to not meet inclusion criteria. One patient with glottic view grade 3 was erroneously intubated via the indirect method. For another patient, the anesthesiologist aborted the protocol due to encountered difficulties.

Outcome measures

Measure

McGrath Mac Intubations n=94 Participants All 100 patients will be intubated using the McGRATH® MAC video laryngoscope, either through direct or indirect vision laryngoscopy. The LCD monitor of the McGRATH™ MAC was initially covered; if the anesthesiologist visualized a modified C-L grade 1-3 view, the patient was intubated utilizing this direct view. If the anesthesiologist observed a modified C-L grade 4 view during their initial direct view, the patient was intubated using the indirect method. If intubation via direct laryngoscopy was unsuccessful on the first attempt, the patient was intubated using the indirect view. If both methods of laryngoscopy were unsuccessful, the rescue intubation technique was performed at the discretion of the anesthesiologist.

Number of Participants on Whom Bougie (Introducer) Was Used to Facilitate Intubation on the First Attempt

12 Participants

SECONDARY outcome

Timeframe: at the time of laryngoscopy

Population: Of the 100 patients recruited, 6 patients were excluded from data analysis. 4 patients were found to not meet inclusion criteria. One patient with glottic view grade 3 was erroneously intubated via the indirect method. For another patient, the anesthesiologist aborted the protocol due to encountered difficulties.

The anesthesiologists rated the McGRATH™ MAC's ability in managing airways as "very easy," "easy," "slight resistance," "difficult," or "not possible." The difficulty of laryngoscopy was evaluated during the insertion and placement of the McGRATH™ MAC, from the patient's lips, into their oropharynx, until a glottic view was obtained.

Outcome measures

Measure	McGrath Mac Intubations n=94 Participants All 100 patients will be intubated using the McGRATH® MAC video laryngoscope, either through direct or indirect vision laryngoscopy. The LCD monitor of the McGRATH™ MAC was initially covered; if the anesthesiologist visualized a modified C-L grade 1-3 view, the patient was intubated utilizing this direct view. If the anesthesiologist observed a modified C-L grade 4 view during their initial direct view, the patient was intubated using the indirect method. If intubation via direct laryngoscopy was unsuccessful on the first attempt, the patient was intubated using the indirect view. If both methods of laryngoscopy were unsuccessful, the rescue intubation technique was performed at the discretion of the anesthesiologist.
Subjective Ease of Laryngoscopy very easy	22 Participants
Subjective Ease of Laryngoscopy easy	29 Participants
Subjective Ease of Laryngoscopy slight resistance	23 Participants
Subjective Ease of Laryngoscopy difficult	19 Participants
Subjective Ease of Laryngoscopy not possible	1 Participants

SECONDARY outcome

Timeframe: at the time of laryngoscopy

Population: Of the 100 patients recruited, 6 patients were excluded from data analysis. 4 patients were found to not meet inclusion criteria. One patient with glottic view grade 3 was erroneously intubated via the indirect method. For another patient, the anesthesiologist aborted the protocol due to encountered difficulties.

The anesthesiologists rated the McGRATH™ MAC's ability in managing airways as "very easy," "easy," "slight resistance," "difficult," or "not possible." The difficulty of endotracheal tube (ETT) delivery (that is, intubation) was evaluated during the insertion of the ETT into the patient's mouth, until the ETT passed the vocal cords.

Outcome measures

Measure	McGrath Mac Intubations n=94 Participants All 100 patients will be intubated using the McGRATH® MAC video laryngoscope, either through direct or indirect vision laryngoscopy. The LCD monitor of the McGRATH™ MAC was initially covered; if the anesthesiologist visualized a modified C-L grade 1-3 view, the patient was intubated utilizing this direct view. If the anesthesiologist observed a modified C-L grade 4 view during their initial direct view, the patient was intubated using the indirect method. If intubation via direct laryngoscopy was unsuccessful on the first attempt, the patient was intubated using the indirect view. If both methods of laryngoscopy were unsuccessful, the rescue intubation technique was performed at the discretion of the anesthesiologist.
Subjective Ease of Intubation very easy	20 Participants
Subjective Ease of Intubation easy	39 Participants
Subjective Ease of Intubation slight resistance	21 Participants
Subjective Ease of Intubation difficult	13 Participants
Subjective Ease of Intubation not possible	1 Participants

Adverse Events

McGrath Mac Intubations

Serious events: 0 serious events

Other events: 48 other events

Deaths: 0 deaths

Serious adverse events

Adverse event data not reported

Other adverse events

Measure	McGrath Mac Intubations n=94 participants at risk；n=100 participants at risk All 100 patients will be intubated using the McGRATH® MAC video laryngoscope, either through direct or indirect vision laryngoscopy. The LCD monitor of the McGRATH™ MAC was initially covered; if the anesthesiologist visualized a modified C-L grade 1-3 view, the patient was intubated utilizing this direct view. If the anesthesiologist observed a modified C-L grade 4 view during their initial direct view, the patient was intubated using the indirect method. If intubation via direct laryngoscopy was unsuccessful on the first attempt, the patient was intubated using the indirect view. If both methods of laryngoscopy were unsuccessful, the rescue intubation technique was performed at the discretion of the anesthesiologist.
General disorders Hoarseness	43.6% 41/94 • Number of events 41 • Adverse Event data include measures of post-operative discomfort upon entering the Post-Anesthesia Care Unit (PACU). Patients enter the PACU within 30 minutes of completion of surgery, and they leave the PACU approximately 1-2 hours after entering the PACU. All 100 patients were assessed for SAEs. 94 patients were assessed for other AEs (not including SAEs): 6 patients were excluded from data analysis; 4 patients were found to not meet inclusion criteria; one patient with glottic view grade 3 was erroneously intubated via the indirect method; and for another patient, the anesthesiologist aborted the protocol due to encountered difficulties.
General disorders Sore mouth	8.5% 8/94 • Number of events 8 • Adverse Event data include measures of post-operative discomfort upon entering the Post-Anesthesia Care Unit (PACU). Patients enter the PACU within 30 minutes of completion of surgery, and they leave the PACU approximately 1-2 hours after entering the PACU. All 100 patients were assessed for SAEs. 94 patients were assessed for other AEs (not including SAEs): 6 patients were excluded from data analysis; 4 patients were found to not meet inclusion criteria; one patient with glottic view grade 3 was erroneously intubated via the indirect method; and for another patient, the anesthesiologist aborted the protocol due to encountered difficulties.
General disorders sore neck	7.4% 7/94 • Number of events 7 • Adverse Event data include measures of post-operative discomfort upon entering the Post-Anesthesia Care Unit (PACU). Patients enter the PACU within 30 minutes of completion of surgery, and they leave the PACU approximately 1-2 hours after entering the PACU. All 100 patients were assessed for SAEs. 94 patients were assessed for other AEs (not including SAEs): 6 patients were excluded from data analysis; 4 patients were found to not meet inclusion criteria; one patient with glottic view grade 3 was erroneously intubated via the indirect method; and for another patient, the anesthesiologist aborted the protocol due to encountered difficulties.
General disorders Sore jaw	2.1% 2/94 • Number of events 2 • Adverse Event data include measures of post-operative discomfort upon entering the Post-Anesthesia Care Unit (PACU). Patients enter the PACU within 30 minutes of completion of surgery, and they leave the PACU approximately 1-2 hours after entering the PACU. All 100 patients were assessed for SAEs. 94 patients were assessed for other AEs (not including SAEs): 6 patients were excluded from data analysis; 4 patients were found to not meet inclusion criteria; one patient with glottic view grade 3 was erroneously intubated via the indirect method; and for another patient, the anesthesiologist aborted the protocol due to encountered difficulties.
General disorders Dysphonia	4.3% 4/94 • Number of events 4 • Adverse Event data include measures of post-operative discomfort upon entering the Post-Anesthesia Care Unit (PACU). Patients enter the PACU within 30 minutes of completion of surgery, and they leave the PACU approximately 1-2 hours after entering the PACU. All 100 patients were assessed for SAEs. 94 patients were assessed for other AEs (not including SAEs): 6 patients were excluded from data analysis; 4 patients were found to not meet inclusion criteria; one patient with glottic view grade 3 was erroneously intubated via the indirect method; and for another patient, the anesthesiologist aborted the protocol due to encountered difficulties.
General disorders Dysphagia	10.6% 10/94 • Number of events 10 • Adverse Event data include measures of post-operative discomfort upon entering the Post-Anesthesia Care Unit (PACU). Patients enter the PACU within 30 minutes of completion of surgery, and they leave the PACU approximately 1-2 hours after entering the PACU. All 100 patients were assessed for SAEs. 94 patients were assessed for other AEs (not including SAEs): 6 patients were excluded from data analysis; 4 patients were found to not meet inclusion criteria; one patient with glottic view grade 3 was erroneously intubated via the indirect method; and for another patient, the anesthesiologist aborted the protocol due to encountered difficulties.
General disorders Alteration in Tongue	3.2% 3/94 • Number of events 3 • Adverse Event data include measures of post-operative discomfort upon entering the Post-Anesthesia Care Unit (PACU). Patients enter the PACU within 30 minutes of completion of surgery, and they leave the PACU approximately 1-2 hours after entering the PACU. All 100 patients were assessed for SAEs. 94 patients were assessed for other AEs (not including SAEs): 6 patients were excluded from data analysis; 4 patients were found to not meet inclusion criteria; one patient with glottic view grade 3 was erroneously intubated via the indirect method; and for another patient, the anesthesiologist aborted the protocol due to encountered difficulties.

Additional Information

Carin A. Hagberg, MD

The University of Texas Health Science Center at Houston

Phone: 713-500-6200

Email: Carin.A.Hagberg@uth.tmc.edu

Results disclosure agreements

• Principal investigator is a sponsor employee
• Publication restrictions are in place