VieScope in Patients With an Expected Difficult Airway

Study Overview
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Brief Summary
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Patients requiring endotracheal intubation for elective surgery with an expected difficult airway are randomized to be intubated either by a) VieScope or b) videolaryngoscopy.

Detailed Description
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Tracheal intubation is required for different surgical procedures for mechanical ventilation and to prevent aspiration of secretions. In patients with an expected difficult airway, tracheal intubation is often performed by videolaryngoscopy (VL). However, this technique has limitations and may fail due to insufficient visualization of the larynx. A new device has been introduced that consists of an illuminated straight plastic tube for laryngoscopy (VSC, Vie Scope, Adroit Surgical, Oklahoma City, OK, USA) that enables for indirect intubation over a stylet. So far, the VSC has shown promising results in manikin studies for intubation in normal and difficult airways. We aim to test the VSC in patients compared to videolaryngoscopy in a prospective randomized non-inferiority trial. Patients will be assessed for eligibility in the Anesthesiology Pre-assessment Clinic of the University Medical Center Hamburg-Eppendorf prior to elective surgery. All patients receive a structured preoperative airway assessment. Patients are randomized 1:1 to either intervention or control group. Patients randomized to the intervention group will be intubated with the VSC. Patients randomized to the control group are intubated with a MacIntosh type videolaryngoscope (CMAC, Storz, Germany).

Official Title
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Tracheal Intubation With VieScope Versus Videolaryngoscopy in Patients for Elective Surgery With an Expected Difficult Airway - a Prospective Randomized Trial (VieScOP-II)

Conditions
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Airway Management

Intervention / Treatment
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* Device: VieScope
* Device: Videolaryngoscopy


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients requiring general anesthesia with transoral tracheal intubation for elective surgery Age ≥ 18 Preoperative airway assessment reveals an expected difficult airway (rated by the responsible anesthetist in the Pre-assessment Clinic based on the existing in-house algorithm) Exclusion Criteria: Pregnant or breastfeeding woman Confirmed indications for awake fiberoptic intubation especially due to enoral, pharyngeal tumors, abscesses or other processes Planned endotracheal intubation without deep anesthesia or neuromuscular blocking agents (e.g. awake videolaryngoscopy) Required transnasal tracheal intubation (e.g. for surgical reasons) Requirement of special endotracheal tubes such as laser or RAE tubes for surgical reasons Patients at risk for pulmonary aspiration who qualify for rapid sequence induction Loose teeth Denial of consent

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Interventional Model Description: randomized 1:1
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: VieScope<br>intubation with the VieScope laryngoscope | Device: VieScope<br>* intubation with VieScope laryngoscope<br>|
| Active Comparator: Videolaryngoscopy<br>intubation with videolaryngoscope | Device: Videolaryngoscopy<br>* intubation with videolaryngoscope<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Percentage of Glottis Opening (POGO) scale | intubating conditions according to the percentage of glottis opening scale (POGO), range 0-100%, higher values better | 15 min | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| first attempt success rate | percentage of successful intubations with one attempt | 15 min | 
| time to intubation | time until tracheal airway access is established | 15 min | 
| Cormack-Lehane | intubating conditions according to Cormack-Lehane | 15 min | 
| overall success rate | percentage of successful intubations with the allocated procedure | 15 min | 
| time to successful intubation with one attempt | time until tracheal airway access is established in patients that are intubated at first attempt | 15 min | 
| intubation difficulty | subjective rating on a visual analogue scale (0-100, higher values indicate more difficult intubation) of the difficulty of airway management and questionnaire | 15 min | 
| number of attempts | total number of attempts until airway established | 15 min | 
| aspiration | percentage of patients that vomit and aspirate during intubation | 15 min | 
| esophageal intubation | percentage of accidental esophageal intubation attempts | 15 min | 
| hypoxia | percentage of patients with a desaturation below a pulsoximetric saturation of 80% | 15 min | 
| hypotension | percentage of patients with a systolic blood pressure below 70 mmHg | 15 min |