Comparison of Four Routinely Used Methods For Positioning of Oral Endotracheal Tube Tip in the Trachea – An Attempt to find a Simple, Easy and Accurate Method in Indian Adults

•A written informed consent for participation in the study will be obtained from each willing patient meeting the inclusion criteria after discussion of the study procedure and expected complications.

•Preoperative evaluation of the patient will be done as per standard protocol.

•Airway assessment will be done and Mallampati class, thyromental distance, mouth opening in the form of inter incisor gap and any restriction in flexion and extension movements of the neck will be noted.

•Patients will be kept nil per os overnight before surgery, as per usual practice.

•In the operation theatre, routine monitoring will be done. Patient will be made to lie supine comfortably in sniffing position.Patient will be taken under general anesthesia by routine protocol.

•Cuffed ETTs available routinely in India and the Sharda hospital, and supplied by M/s Romsons Group Pvt Ltd. shall be used for the study.

•Endotracheal tubes will be especially marked proximal to the proximal rim of the cuff at 0.5 cm distances and shall be used in all the groups to know the distance between the proximal rim of cuff to the vocal cords after the positioning of the ETT according to allotted method.

•After the hemodynamic variables have stabilized, 100% oxygen saturation ensured and adequate depth of anaesthesia achieved, the connector of the TT will be disconnected from the anesthetic circuit and fibreoptic endoscope introduced through the tube to measure the distances from within the trachea.

•All these measurements will be taken at the end of expiration and the lungs would be ventilated normally in between the measurements.

•Measurements would be taken at  separate depths,the carina and the tip of the tracheal tube. At each depth an adherent marker will be placed on the endoscope shaft

•Fiberscope shall be withdrawn and measurements from the tip of the fiberscope to each of the markers shall be noted and distance from the tip of the tracheal tube to the carina calculated using these values.

•Auscultation of chest shall be done in all patients after placement of the TT irrespective of the group to reinsure and confirm adequate and satisfactory ventilation

• End tidal capnography will also be routinely done as a part of routine essential monitoring.

•Anaesthesia will be maintained according to the standard guidelines practiced for all general anaesthesia cases.