A Comparison of Vie-Scope and Macintosh Blade Laryngoscopes in Morbidly Obese.

A Comparison of Visualization of the Larynx With the Vie Scope Versus Standard Macintosh Laryngoscope in Morbidly Obese Patients.

Macintosh laryngoscope is still considered a standard for tracheal intubation, however, visualization of the glottis may be inadequate mainly in morbidly obese patients. The Vie Scope is a novel type of laryngoscope consisting of a straight, shielded, illuminated tube that offers intubation via a bougie using the paraglossal technique. In this prospective, non-randomized study, we tested the research hypothesis that the use of Vie Scope may improve visualization of the larynx in comparison with the Macintosh blade.

Prior to tracheal intubation, all patients were placed in the head-elevated laryngoscopy position (HELP). All study subjects were anesthetized with the concordance to European Society for Peri-Operative Care of Obese Patient (www.espcop.eu) protocols: proper positioning, pre-oxygenation with CPAP, induction of anesthesia with propofol 2.0 mg kg-1 of corrected body weight; for muscle relaxation rocuronium 0.6 mg kg-1 of ideal body weight (IBW); ketamine 50 mg ; lidocaine 100 mg, and fentanyl 0.1 mg. After achieving 100% neuromuscular block confirmed by TOF-Watch monitoring, laryngoscopy was performed by the anesthesiologist familiar with the use of both Vie Scope and Macintosh blade laryngoscope, and also experienced in bariatric anesthesia. All anesthesiologists participating in the study underwent training with Vie Scope on the manikin model.

The evaluation of glottis visualization in direct laryngoscopy using Cormack-Lehane scale (CL) in all patients was performed in sequence using two laryngoscopes: first Macintosh blade laryngoscope (MCL) and then Vie Scope laryngoscope (VS). Tracheal intubation was performed with the VS. The study subjects all received oxygen using nasal CPAP in order to maintain sufficient oxygenation

Inclusion Criteria:

• morbid obesity BMI>40 kg/m2
• scheduled for elective bariatric procedure
• no anatomy abnormalities of upper airway

Exclusion Criteria:

• lack of conscent
• predicted difficult intubation