Incidence of Sore Throat With Traditional Intubation Blades or Glidescope Blade

The goal of this study is to determine whether the use of the GlideScope™ video laryngoscope during intubation leads to a greater or lesser incidence of sore throat when compared to traditional laryngoscope blades used for intubation, such as the Macintosh or Miller blade. During postoperative checks by a board certified anesthesiologist at the Albany Medical Center (AMC) Hospital, it was noticed that patients who reported sore throat often required intubation with the GlideScope™. Standard of care at the AMC Hospital dictates that the Glidescope is used as a "rescue" device for failed direct laryngoscopy on a difficult airway; if traditional direct laryngoscopy with a Macintosh or Miller blade cannot provide adequate laryngeal views, progression to a different airway device such as the Glidescope or fiberoptic scope is indicated. The initial attempt with direct laryngoscopy on a difficult airway often requires utilization of McGill forceps, which increases the chance of upper airway injury prior to the rescue attempt with the GlideScope. Consequently, it is difficult to determine whether patients' reports of post-operative sore throat are caused by the irritation inflicted by the multiple laryngoscopic attempts required in patients where the Glidescope was needed as a rescue method, or whether it is due to the actual utilization of the Glidescope itself.

Previous studies have shown that the use of a GlideScope™ decreases the likelihood of upper airway injury by decreasing the lower mean force applied during laryngoscopy when compared to a Macintosh laryngoscope; however, this study was done using manikins and it is not known whether this result can be translated to a patient oriented outcome. Another study compared the GlideScope™ to direct laryngoscopy for nasotracheal intubation. Their results suggested that the incidence of postoperative moderate or severe sore throat was significantly reduced with use of the GlideScope™ videolaryngoscope. However, other studies have shown increased incidence of postoperative sore throat with Glidescope usage when compared to other videolaryngoscopes and conventional Macintosh laryngoscope as a primary laryngoscopy method. In light of these studies, none have attempted a direct comparison of a Glidescope with conventional Macintosh/Miller laryngoscope blades with incidence of sore throat as a primary outcome of interest.

The purpose in this study is to determine whether there is a difference in the incidence of postoperative sore throat when using the GlideScope™ versus a traditional intubation blade involving patients that are not anticipated to have a difficult airway. Exclusion of patients with difficult airways allows us to perform direct comparisons with the Glidescope and conventional direct laryngoscopy without compromising standard of care or increasing patient risk, which will be determined by the use of standard of care preoperative exams.

Inclusion criteria

• Male or female, aged 18 - 80 years old.
• Able to provide written informed consent and to comply with all study procedures
• Scheduled for elective inpatient or outpatient surgery requiring general anesthesia and orotracheal intubation.

Exclusion criteria

• Known difficult airway based on prior medical history
• American Society of Anesthesiologists physical status score > IV
• Presence of abnormal cervical spine movement (normal > 90°)
• Airway Mallampati score ≥ III
• Thyromental distance ≥ 6
• Upper lip bite test ≥ 3
• Degree of retrognathia
• Previous medical history indicating patient has a known difficult airway
• Judgment that patient will require intubation post-operatively
• Are emergency surgery cases
• Are Ear-Nose-Throat (ENT) or neck surgery cases
• Have a planned post-operative ICU stay
• Inadequate Nil Per Os (NPO) status prior to surgical case
• Prisoner status