Endotrol-tracheal Tube Assisted Endotracheal Intubation During Video Laryngoscopy

It is estimated that endotracheal intubation is performed on some 8 million patients per year in the United States. Of these endotracheal intubations, approximately 80% are performed by direct laryngoscopy with transoral placement of the endotracheal tube (ET) into the trachea. There is fairly uniform reporting of the incidence of failed intubation in the literature; it occurs in approximately 0.05% or 1:2230 of surgical patients and in approximately 0.13% to 0.35%, or 1:750 to 1:280, of the obstetric patients.1,2 The incidence of unsuspected difficult intubation is estimated to be higher at 3%. One factor that contributes to difficult intubation is poor visualization of the airway. Video laryngoscopes are a relatively new edition to the armamentarium of airway devices available to the airway manager. Although these instruments are more expensive than traditional direct laryngoscopes, they offer several advantages that may justify their expense. Although some clinicians may espouse the routine use of video laryngoscopy, most providers reserve it for anticipated difficult situations or as "plan B" after failed intubation by direct laryngoscopy (DL). There are several advantages of a video intubation technique as compared to direct laryngoscopy. The video laryngoscopes have been shown to provide superior views to traditional laryngoscopy as well as in difficult intubations.3-5 Video intubation techniques, by allowing tracheal intubation monitoring, have been shown to improve the safety of the procedure and increase intubation success. The GlideScope consists of a digital camera, called a video baton, which fits into a plastic laryngoscope blade and a light source on the side to provide a video image of airway structures on a screen, which can be conveniently located directly in front of the anesthesiologist. The GlideRite rigid stylet conforms to the GlideScope blade angulation, which,eliminates the need to manually shape the stylet to fit down the airway and improves maneuverability in endotracheal tube placement.

It should be noted that several reports have been published describing trauma to the upper airway (anterior tonsillar pillar, soft palate) during intubation with video laryngoscopes. Recently, several reports using endoflex tube (which is similar to the endotrol tube) showed that there is considerable usefulness in normal direct laryngoscopy and video laryngoscopy (using glidescope) as well. The purpose of this study is to compare the safety and efficacy of Endotrol Tube (Covidien, Colorado, USA) compared to the conventional endotracheal tube in conjunction with the GlideRite stylet during videolaryngoscopy assisted endotracheal intubation.

INSTRUMENTS:

McGrath Video Laryngoscope (MVL) - A video-based system for tracheal intubation that utilizes a video camera embedded into a "camera stick". The resulting video image is displayed on a small color Liquid Crystal Display (LCD) attached to the top of the handle of the device, which can be adjusted to obtain the best view. The unit is powered with a single easily-replaced AA battery and features a single electronic control: an on/off switch located on the top of the unit. The device is available with an adjustable curved MAC blade (sizes 3 to 5). Also,the device features a sterile disposable transparent blade sheath preventing cross infection.

GlideScope Video Laryngoscope (GVL)- The GlideScope was commercially introduced in 2001. The 1- piece handle and blade is made of medical- grade plastic. It has a vertical profile of 14.5 mm, a midblade bend of 50-60 degrees, and a video camera with a light-emitting diode housed toward the distal end of the blade. The image captured by the camera is transferred by the attached cable to a color liquid crystal display (LCD). A heating element covers the camera lens and ensures effective antifogging after the device has been turned on for 15- 30 seconds. The blades can be sterilized and reused, and are available in 3 sizes: large (adult), midsize (pediatric), and small (neonatal). As the image is transferred to the LCD display, anesthesiologists are able to view key anatomical landmarks at the earliest possible time, facilitating navigation. Also, in cases requiring external laryngeal manipulation, the assistant can see the effect of the maneuver on the monitor simultaneously with the anesthesiologist for quicker, more efficient intubation. Endotrol Tracheal Tube (ETT) (Covidien, Colorado, USA) - A sterile, single lumen, disposable ET with a built- in flexing mechanism with a standard 15 mm connector. The tube provides directional tip control via an operator- activated ring loop and incorporates a self- sealing valve with attached pilot balloon. The ETT is specifically designed for use in cases where difficult intubation can be aided with directional tip control. Due to the Hi-Lo cuff design, the ETT is acceptable for oral/nasal intubation of the trachea for anesthesia and in cases where the intubation duration is expected to be more than 24 hours or unpredictable. The special way to hold the ETT is to place the thumb of the right hand against the end of the 15 mm connector and the index finger in the ring loop. Pulling on the ring loop causes the tip to turn anteriorly towards the tracheal opening.