Evidence-based Algorithm for the Expected Difficult Intubation

Completed

• Conditions: Airway Management; Intubation, Intratracheal
• Interventions: Other: No intervention, observational study

• Registration Number: NCT04863846
• Lead Sponsor: Universitätsklinikum Hamburg-Eppendorf

Brief Summary

The Expect-it study aims to accompany the development and clinical implementation process of a new algorithm for the management of expected difficult intubation. The new algorithm is designed to allocate patients to specific tracheal intubation techniques. After assessing the status quo (non-algorithm-based decision-making) the new algorithm-based allocation will be compared with this clinical standard within a confirmatory diagnostic accuracy study (post-implementation).

Detailed Description

Difficult tracheal intubation is one of the major reasons for anesthesia-related adverse events. Patients undergoing ear, nose \& throat (ENT) or oral and maxillofacial (OMS) surgery often require tracheal intubation for general anesthesia but are at increased risk for difficult tracheal intubation. Currently, existing preoperative tests for the prediction of difficult intubation show low diagnostic accuracy. Moreover, as the results of these prediction tests are not coupled with concrete treatment recommendations, they cannot be used targeted within preventive concepts. An evidence based rational algorithm for the management of expected difficult intubation has not been developed yet. It is unknown, if an algorithm-based allocation to an intubation approach might be advantageous compared with a non-algorithm-based allocation strategy.

The Expect-it study aims to accompany the development and clinical implementation process of a new algorithm for the management of expected difficult intubation. This new algorithm is designed to provide an evidence-based decision-making tool for a rational pre-choice of tracheal intubation techniques, anesthetized intubation by direct laryngoscopy (DL) or videolaryngoscopy (VL) or awake tracheal intubation (ATI). In the first study phase the status quo (clinical standard, non-algorithm-based decision-making) will be assessed (three-month period with an approximated case number of up to 600 patients). The Expect-it algorithm will be implemented thereafter. Between both study phases, the algorithm will be updated (based on the findings of the first phase), sensitivity and specificity of the clinical standard will be calculated, sample size will critically be appraised and readjusted (approximately 600 within at least three months), if appropriate. The second study phase is a confirmatory diagnostic accuracy study for the new algorithm with a single test study design, that aims to proof, if the new Expect-it algorithm is superior or at least non-inferior to the clinical standard, defined as superiority in either the specificity or sensitivity and non-inferiority in the other co-primary endpoint in each domain (ATI, DL, VL) (pre-planned preliminary analysis of the first study phase; IRB amendment 2021-10459_2-BO-ff, December 3, 2021). Sensitivity and specificity are considered co-primary endpoints. Study planning and conduction is in accordance with the Standards for Reporting Diagnostic accuracy studies (STARD) statement. The Expect-it study will further include two surveys among anesthetist in the study center in order to evaluate challenges and obstacles associated with the implementation process and possible clinical implications of the algorithm. An additional analysis will be performed to test a core data set for an 'anesthesia alert card'.

Study Timeline

• Study First Submitted: 2021-04-13
• Study First Submitted QC: 2021-04-24
• Study First Posted: 2021-04-28
• Study Start: 2021-05-01
• Primary Completion: 2022-01-29
• Study Completion: 2022-01-29
• Status Verified: 2022-03
• Last Update Submitted: 2022-03-01
• Last Update Posted: 2022-03-02

Recruitment & Eligibility

• Status: COMPLETED
• Sex: All
• Target Recruitment: 1282

Inclusion Criteria

• Patients undergoing ENT or OMS surgery that require general anesthesia with tracheal intubation (either DL, VL or ATI)
• Age ≥ 18 years

Exclusion Criteria

• Denial of consent
• Planned intubation technique is not designated in the study protocol as it differs from either DL, VL, ATI (e.g. primary tracheotomy or rigid bronchoscopy)

Study & Design

• Study Type: OBSERVATIONAL
• Study Design: Not specified

Arm && Interventions

Group	Intervention	Description
Clinical standard (first study phase)	No intervention, observational study	Current clinical standard, non-algorithm-based decision-making (prior to implementation of the algorithm)
Algorithm-based allocation (second study phase)	No intervention, observational study	New algorithm-based allocation to an intubation technique (after implementation of the algorithm)

Primary Outcome Measures

Name	Time	Method
First phase: sensitivity and specificity (co-primary endpoints) of the clinical standard	3 months	Clinical assessment
Second phase: sensitivity and specificity (co-primary endpoints) of 'DL recommendation' by the algorithm vs. 'VL/ATI'	3 months	Clinical assessment
Second phase: sensitivity and specificity (co-primary endpoints) of 'ATI recommendation' by the algorithm vs. 'VL/DL'	3 months	Clinical assessment
Second phase: sensitivity and specificity (co-primary endpoints) of 'VL recommendation' by the algorithm vs. 'DL/ATI'	3 months	Clinical assessment

Secondary Outcome Measures

Name	Time	Method
Quality of care of the current clinical standard and the effects of algorithm implementation	7 months	Survey among anesthetist
Post-intubation recommendation for an anesthesia alert card	1 hour	Recommendation of the responsible anesthetist
Best glottic view	1 hour	Grading according to the Cormack Lehane classification (I-IV)
Number of attempts	1 hour	Total number of attempts until airway established
Post-intubation recommendation for an intubation method	1 hour	Recommendation of the responsible anesthetist
First pass success rate	1 hour	Percentage of successful intubations with one attempt
Post-intubation diagnosis 'difficult intubation'	1 hour	Rating of the responsible anesthetist
Post-intubation diagnosis 'difficult face-mask-ventilation'	1 hour	Rating of the responsible anesthetist
Classification of intubation difficulty (VIDIAC classification)	1 hour	Rating between -1 and 5 points
Overall success rate of the first choice technique	1 hour	Percentage of successful intubation without transition to another technique
Lowest oxygen saturation	1 hour	Measured with pulse oxymetry during anesthesia induction
Overall intubation difficulty, ease of intubation, quality of visualization	1 hour	Subjective ratings on visual analogue scales (0 to 100 with 0 being the best)
Airway-related adverse events	1 hour	Laryngospasm, bronchospasm, larynx trauma, airway trauma, soft tissue trauma, oral bleeding, edema, dental damage, corticosteroid application, accidental esophageal intubation, aspiration, hypotension or hypoxia
Patient discomfort, satisfaction, symptoms	12 hours	Clinical assessment during follow-up
Clinical evaluation of a core dataset 'anesthesia alert card'	10 months	Rating of various anesthetist
Intubation time	1 hour	Time to successful tracheal intubation

Trial Locations

Locations (1)

University Medical Center Hamburg-Eppendorf; 🇩🇪 Hamburg, Germany