Flexible Intubation Scope With or Without Video Laryngoscope in Supporting Endotracheal Tube Placement in Patients With Head and Neck Cancer Before Surgery

PRIMARY OBJECTIVES:

I. To compare the rates of difficult endotracheal tube (ETT) placement using a flexible intubation scope (FIS) versus a combination of flexible intubation and video laryngoscopy in difficult airway management.

SECONDARY OBJECTIVES:

I. To compare the ease of using a flexible intubation scope (FIS) with and without the use of the video laryngoscope (VL).

II. Total time for securing the airway.

III. Number of attempts required for intubation.

IV. Rate of failure at intubation.

V. Incidence of desaturation.

VI. Assessment for hoarseness, sore mouth, neck, or jaw, dysphonia, dysphagia, lip injury, tongue injury, or tooth damage.

OUTLINE: Patients are randomized to 1 of 2 arms.

ARM A: Patients undergo flexible scope intubation up to 2 attempts following induction of general anesthesia and adequate manual ventilation. In case of failed 2 attempts, patients undergo a third attempt utilizing another technique or device.

ARM B: Patients undergo flexible scope intubation and video laryngoscopy up to 2 attempts following induction of general anesthesia and adequate manual ventilation. In case of failed 2 attempts, patients undergo a third attempt utilizing another technique or device.

• Laryngoscopy (Device): Undergo video laryngoscopy
• Tracheal Intubation (Procedure): Undergo flexible scope intubation

Primary outcomes

• Difficult Endotracheal Tube (ETT) Placement [intubation time, up to 3 minutes]: Defined as the number of participants with any of the following during initial intubation attempt.1 Intubation time exceeding 60 seconds, 2. Failure to intubate on the first attempt, 3. Provider assessment of intubation as difficult or unsuccessful.

Secondary outcomes

• Intubation Time [time captured when FIS passed the lips to CO2 confirmation]: Time from induction to successful intubation
• Number of Intubation Attempts [intubation time, up to 3 minutes]: Number of Intubation Attempts
• Rate of Failure at Intubation [during intubation process/attempt]: Failed Airway Rate
• Ease of Intubation (Provider Assessment) [duration of intubation attempt]: The number of people who had 1= extremely easy, 2=somewhat easy, 3=resistance, 4= difficult, 5= unsuccessful (for both groups)

Sex: All, ages: 18 Years to any

Inclusion Criteria:

* Ages ≥ 18 years of age
* All surgical patients with known or suspected difficult airways that meet at least three (3) of the Difficult Airway criteria \[Mallampati III-IV, Neck circumference > 40 cm, Sternomental distance < 12 cm, Thyromental distance < 6 cm, Mouth opening < 4 cm, BMI ≥ 35 kg/m2, Upper Lip Bite Test - ULBT (class III)\] or history of radiation to the head and neck area or oral pathology obstructing the glottic view
* American Society of Anesthesiology (ASA) I-IV
* Has provided written informed consent

Exclusion Criteria:

* Active bleeding from nasopharynx or oropharynx
* Trismus
* Oral pathology obstructing the glottic view
* Planned awake or nasal intubation
* Neuromuscular Blockade (NMB) contraindicated post-induction
* Emergency endotracheal intubation and patients intubated pre and post-surgery
* Surgical procedures such as Tracheostomy, Laryngectomy, Esophagectomy
* Patient refusal or inability to consent for study participation
* American Society of Anesthesiology (ASA) V
* Pregnant females

Participant flow

Outcome results

• Difficult Endotracheal Tube (ETT) Placement (Primary), Count of participants, Participants: Flexible Intubation Scope (FIS) 40; Flexible Intubation Scope + Video Laryngoscope (FIS+VL) 29
• Intubation Time (Secondary), Mean, seconds: Flexible Intubation Scope (FIS) 58.37 (51.44 to 65.30); Flexible Intubation Scope + Video Laryngoscope (FIS+VL) 50.92 (44.04 to 57.80)
• Number of Intubation Attempts (Secondary), Count of participants, Participants: Flexible Intubation Scope (FIS) 50; Flexible Intubation Scope + Video Laryngoscope (FIS+VL) 54
• Rate of Failure at Intubation (Secondary), Number, percentage of participants: Flexible Intubation Scope (FIS) 7.81 (7.76 to 26.86); Flexible Intubation Scope + Video Laryngoscope (FIS+VL) 1.72 (0.42 to 11.91)
• Ease of Intubation (Provider Assessment) (Secondary), Count of participants, Participants: Flexible Intubation Scope (FIS) 31; Flexible Intubation Scope + Video Laryngoscope (FIS+VL) 40

Adverse events

Time frame: From induction to one hour after PACU arrival, up to 6 hours

• Study Protocol and Statistical Analysis Plan (PDF, 2024-11-20)

• Carin Hagberg, Principal investigator, M.D. Anderson Cancer Center