Tracheal Tube Cuff Inflation-Deflation Method for Video Assisted Laryngoscope Nasal Intubation in Adults

Magill forceps is used to maneuver the endotracheal tube (ETT) in the posterior oropharynx and place its tip into the laryngeal inlet. While the Magill forceps are useful in guiding the nasotracheal tube past the vocal cords, care must be taken to avoid excessive maneuvering in order to minimize the risk of local trauma and rupture of the nasotracheal tube balloon.

Cuff inflation-deflation method can reduce the apnea time in the adult patients. This, in turn, could point to a reduction in the complications (as desaturation and cardiac arrhythmia) that associated with the prolonged-time procedure.

Written informed consent will be obtained from all patients participating in the trial. The trial will be registered prior to patient enrollment. Ninety patients between the ages of 18 and 60 years with American Society of Anesthesiologists (ASA) physical status I -II , scheduled for elective surgery (dental and maxillofacial) will be enrolled in a prospective randomized observer blinded clinical trial. Patients, who have coagulopathies, have upper airway abnormalities, at risk for aspiration or patient's refusal will be excluded from the study.

Materials and methods

Airway management is subdivided into phases:

Phase 1 :Passage of the endotracheal tube through the nose into the pharynx Phase 2 : Video-laryngoscope-guided passage of the endotracheal tube through the pharynx into the trachea.

Patients will be randomized into 2 groups according to phase 2:

Group A (45 patients) will be performed with tracheal tube cuff inflation-deflation method. Tracheal tube cuff will be inflated with 15-20 ml of air (volume of air is depending on the level of larynx). Once the tip of ETT at the laryngeal inlet, the cuff of ETT will be deflated and advanced into the trachea.

Group 2 (45 patients) will be performed using the Magill forceps to guide the ETT tip to pass through the pharynx and glottis into the trachea.

Patients will be randomly assigned on a one-to-one ratio. Randomization will be performed outside the study center by means of a computer generated random- numbers table. Group allocation will be concealed in sealed opaque envelopes that will not be opened till the last practical moment.

The nasal intubation will be performed behind an opaque screen so that observer could not see which approach will be used. All procedures were performed preoperatively by the attending anesthetists, who have the same substantial expertise (at least 3 years) in the video laryngoscopy assisted nasal intubation in adult patients. Patient demographics, type and duration of surgery, and the patient's ASA physical status will be recorded.

• to test whether the inflation-deflation method would decrease the need for Magill forceps in video laryngoscopy assisted nasal intubation in pediatric patients compared with the conventional non-cuff inflation approach. [Time frame: Intraoperaotive]
• The number of attempts required for successful nasal intubation. [Time frame: Intraoperaotive]
• Amount of injected air for cuff inflation [Time frame: Intraoperaotive]
• Assessment of side effects of using Magill forceps during nasal intubation [Time frame: Intraoperaotive]
• Evaluation of oxygenation state during nasal intubation [Time frame: preoperative and intraoperative]
• evaluate the anesthetists' experience of using the inflation-deflation method for nasal intubation. [Time frame: 20 minutes after patient recovery]
• Need for external compression and need for help [Time frame: Intraoperaotive]
• need of endotracheal tube rotation [Time frame: Intraoperaotive]