NCT04716218

Brief Summary

In patients with limited neck extension and mouth opening due to reasons including previous radiation therapy in the head and neck area or cervical spine pathology, tracheal intubation with direct laryngoscopy (DL) are challenging because of the difficulty in aligning the oral, pharyngeal, and laryngeal axes in order to visualize the cords. In contrast, video-laryngoscopes (VL) only require alignment of the pharyngeal and laryngeal axes, which lie along much more similar angles when compared with the oral axis. Thus, VL make tracheal intubation easier to accomplish in these patients. Good patient positioning also maximizes the chance of successful laryngoscopy and tracheal intubation. In difficult airway society 2015 guidelines, advantages of head-up positioning and ramping, which brings the patient's sternum onto the horizontal plane of the external auditory meatus (EAM), are highlighted. In the obese patient, the 'ramped' position should be used routinely because this improves the view during DL. This position is usually achieved by placing blankets or other devices under the patient's head and shoulders, but can also be achieved simply by configuring the operation room (OR) table into a back-up head elevated (BUHE) position. Significantly improved glottic views on DL have been reported with both obese and non-obese adult patients in BUHE position. However, the effect of this simple maneuver on laryngeal visualization with the VL in patients with limited neck extension and mouth opening has not been reported. The investigators hypothesized that BUHE position might improve laryngeal views and make intubation easier compared to the supine position with the VL in patients with simulated difficult airway (application of a cervical collar to limit mouth opening and neck movement).The investigator investigated primarily the improvement in visualization of the glottis and, secondarily, the ease of tracheal intubation after alignment of the EAM and sternal notch.

Trial Health

87
On Track

Trial Health Score

Automated assessment based on enrollment pace, timeline, and geographic reach

Enrollment
64

participants targeted

Target at P50-P75 for not_applicable

Timeline
Completed

Started Jan 2021

Shorter than P25 for not_applicable

Geographic Reach
1 country

1 active site

Status
completed

Health score is calculated from publicly available data and should be used for screening purposes only.

Trial Relationships

Click on a node to explore related trials.

Study Timeline

Key milestones and dates

First Submitted

Initial submission to the registry

January 12, 2021

Completed
6 days until next milestone

Study Start

First participant enrolled

January 18, 2021

Completed
2 days until next milestone

First Posted

Study publicly available on registry

January 20, 2021

Completed
2 months until next milestone

Primary Completion

Last participant's last visit for primary outcome

March 31, 2021

Completed
Same day until next milestone

Study Completion

Last participant's last visit for all outcomes

March 31, 2021

Completed
Last Updated

January 29, 2026

Status Verified

January 1, 2026

Enrollment Period

2 months

First QC Date

January 12, 2021

Last Update Submit

January 28, 2026

Conditions

Outcome Measures

Primary Outcomes (1)

  • POGO score

    percentage of glottic opening

    During laryngeal visualization by laryngoscope over 1 minute period

Secondary Outcomes (2)

  • intubation time

    The time from the insertion of laryngoscope into oral cavity until its removal over 1 minute period

  • ease of tracheal intubation

    The time from the insertion of laryngoscope into oral cavity until tracheal intubation over 1minute period

Study Arms (2)

neutral position

PLACEBO COMPARATOR

The initial percentage of glottic opening (POGO) by laryngoscopy was recorded in the ramped position. Thereafter, a second POGO (laryngeal view) was scored in the neutral position and then intubation was performed.

Procedure: back up head elevated position

back up head elevated position

EXPERIMENTAL

The initial POGO was recorded in the neutral position. The second POGO was scored in the ramped position and then the trachea was intubated.

Procedure: back up head elevated position

Interventions

The patient was then placed in the back-up position to align the external auditory meatus and sternal notch, which was achieved by breaking the operating table at the hips to prevent patients from sliding off the table.

back up head elevated positionneutral position

Eligibility Criteria

Age18 Years - 80 Years
Sexall
Healthy VolunteersYes
Age GroupsAdult (18-64), Older Adult (65+)

You may qualify if:

  • patients of ASA physical status 1-2 who were scheduled for elective surgery under general anaesthesia requiring tracheal intubation

You may not qualify if:

  • if they required rapid sequence induction; had a history of previous difficult direct laryngoscopy and required awake tracheal intubation; were unable or unwilling to provide informed consent; had uncontrolled hypertension; had a history of ischaemic heart disease without optimal control of symptoms; had a history of acute or recent stroke or myocardial infarction; had cervical spine instability or cervical myelopathy; had symptomatic asthma or reactive airway disease requiring daily pharmacological treatment for control of symptoms; or had a history of gastric reflux.

Contact the study team to confirm eligibility.

Sponsors & Collaborators

Study Sites (1)

Kangnam Sacred Heart Hospital, Hallym University College of Medicine

Seoul, South Korea

Location

Related Publications (1)

  • Chun EH, Chung MH, Kim JE, Kim KM, Lee HS, Son JM, Park J, Jun JH. Effects of head-elevated position on tracheal intubation using a McGrath MAC videolaryngoscope in patients with a simulated difficult airway: a prospective randomized crossover study. BMC Anesthesiol. 2022 May 30;22(1):166. doi: 10.1186/s12871-022-01706-5.

Study Design

Study Type
interventional
Phase
not applicable
Allocation
RANDOMIZED
Masking
QUADRUPLE
Who Masked
PARTICIPANT, CARE PROVIDER, INVESTIGATOR, OUTCOMES ASSESSOR
Purpose
PREVENTION
Intervention Model
CROSSOVER
Sponsor Type
OTHER
Responsible Party
PRINCIPAL INVESTIGATOR
PI Title
Associate professor

Study Record Dates

First Submitted

January 12, 2021

First Posted

January 20, 2021

Study Start

January 18, 2021

Primary Completion

March 31, 2021

Study Completion

March 31, 2021

Last Updated

January 29, 2026

Record last verified: 2026-01

Data Sharing

IPD Sharing
Will not share

Locations