Effect of Back up Head Elevated Position on Laryngeal Visualization.

Effect of Back up Head Elevated Position on Laryngeal Visualization With the Video-laryngoscope in Patients With Simulated Difficult Airway.

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.

Study Overview

• Status: Recruiting
• Conditions: Intubation;Difficult
• Intervention / Treatment: Procedure: back up head elevated position

• Study Type: Interventional
• Enrollment (Anticipated): 64
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Joo Hyun Jun, MD, PhD; Phone Number: +82-2-829-5740; Email: ilpleut@naver.com

Study Locations

• Korea, Republic of
  • Seoul, Korea, Republic of
    • Recruiting
    • Kangnam Sacred Heart Hospital, Hallym University College of Medicine

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 80 years (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

Description

Inclusion Criteria:

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

Exclusion Criteria:

• 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.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Prevention
• Allocation: Randomized
• Interventional Model: Crossover Assignment
• Masking: Quadruple

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Placebo Comparator: neutral position; 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; 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.
Experimental: back up head elevated position; 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; 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.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
POGO score	percentage of glottic opening	During laryngeal visualization by laryngoscope over 1 minute period

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
ease of tracheal intubation	number of optimization procedure to facilitate laryngeal visualization and tracheal intubation	The time from the insertion of laryngoscope into oral cavity until tracheal intubation over 1minute period
intubation time	time required for intubation	The time from the insertion of laryngoscope into oral cavity until its removal over 1 minute period

Collaborators and Investigators

• Sponsor: Hallym University Kangnam Sacred Heart Hospital

Publications and helpful links

General Publications

• 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 record dates

Study Major Dates

• Study Start (Actual): January 18, 2021
• Primary Completion (Anticipated): March 31, 2021
• Study Completion (Anticipated): March 31, 2021

Study Registration Dates

• First Submitted: January 12, 2021
• First Submitted That Met QC Criteria: January 15, 2021
• First Posted (Actual): January 20, 2021

Study Record Updates

• Last Update Posted (Actual): February 21, 2021
• Last Update Submitted That Met QC Criteria: February 18, 2021
• Last Verified: February 1, 2021

More Information

Terms related to this study

• Other Study ID Numbers: 2020-09-009

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: No

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No