The Effect of The Use of a Videolaryngoscope and/or Stylet on Intubation Time in Obese Patients

The Effect of The Use of a Videolaryngoscope and/or Stylet on Intubation Time in Obese Patients: A Randomized Clinical Trial

Although many researchers would agree that obesity per se is not a risk factor for difficult intubation, there are many well known obesity-related challenges in airway management including difficulty with mask ventilation, more frequent and rapid oxygen desaturation, increased oxygen consumption, and increased sensitivity to the respiratory depressant effects of anesthetic and analgesic drugs. Hence, in these conditions, rapid and nontraumatic intubation gain higher interest. There is controversy about using videoaryngoscopy (VL) in obese patients in these difficult situations. The primary aim of this study is to compare, in terms of intubation time, VL,VL plus stylet and direct-laryngoscopy(DL) plus stylet combination with DL alone in obese patients.

Patients who will be scheduled for surgeries requiring endotracheal intubation, with a body mass index (BMI) more than 30 kg/m2, will be included to this study. During preanesthetic visit (performed by an anesthesiologist not involved in this study) history of difficult intubation, measurement of common predictive indices for difficult intubation (BMI, thyromental distance, neck circumference, Mallampati grade, interincisal [or intergingival] distances), and evaluation of status of dentition and neck movement will be noted.

In the operating room, all patients will be connected to standard monitoring devices. Anesthesia induction will be carried out according to our hospital obese patient anesthesia management protocol. Then, after induction of anesthesia, the patients will be intubated one of four pre-defined protocols that will be determined via randomization during a preanesthetic visit by a person who is unfamiliar with the research protocol.

Primary hypothesis of this study is; using a video-laryngoscope plus stylet will reduce the time required to achieve successful tracheal intubation in obese patients.

Inclusion Criteria:

• Patients with a documented body mass index (BMI) of ≥ 30.
• Patients scheduled to undergo inpatient surgery procedures under general anesthesia.
• Willingness and ability to sign an informed consent document 18 - 80 years of age

Exclusion Criteria:

• Patients who are deemed to be such a significant of an airway risk that they necessitate awake fiberoptic intubation
• Patients with a history of facial abnormalities, oral-pharyngeal cancer, or reconstructive surgery
• Emergency surgeries
• Pregnancy
• Any other conditions or use of any medication which may interfere with the conduct of the study.