After ethics approval subjects will be recruited into the study after informed and written consent, prospective observational study will be done in patients undergoing elective PCNL(prone) and URSL, TURBT(lithotomy) surgeries under general anesthesia requiring oral endotracheal tube. Each group has 30 patients each

Preoperative:

Thorough history about patients past and present illness will be taken along with general and systemic examinations being done. Routine investigations will be done. Height, weight and nutritional status of the patient are noted. Airway assessment will be done using mallampati grading with patient in sitting position head neutral mouth open as wide as possible and maximal tongue protrusion without phonation along with other airway parameters like thyromental distance, sternomental distance,inter incisor distance, neck circumferences.

Intraoperative:

Patients will be shifted to the OT after fasting status is confirmed. All the ASA standard monitors connected. IV lines secured. Patient is preoxygenated with 100% oxygen for 3 minutes. Premedicated with glycopyrrolate and Fentanyl 1-2 mcg/kg. Patient induced with propofol 1-2mg/kg and sevoflurane 2%. After the ability to ventilate is confirmed, relaxant atracurium is given 0.5 mg/kg. Bag mask ventilation is done for 3mins. Tracheal intubation is done with appropriate oral endotracheal tube bilateral air entry confirmed and fixed and connected to mechanical ventilation. Number of attempts for intubation, use of bougie(if any) and duration of intubation is noted. Anaesthesia is maintained on sevoflurane 2% ,Oxygen , Air, and intermittent relaxant boluses. Appropriate analgesia is given. Duration of surgery, amount of intraoperative fluids given, amount of irrigating fluids used are noted. Post procedure patients are  reversed of neuromuscular blockade  with neostigmine 50mcg/kg and glycopyrrolate 10mcg/kg. After assessing the patient’s spontaneous breath attempts and attaining adequate muscle power trachea is extubated.

Postoperative:

Patient is followed up postoperatively at 4hrs, 8hrs, 12hrs,24hrs, 48hrs, 72hrs, intervals and the MPG grade is noted in sitting position without phonation with maximal mouth opening and tongue protrusion with head in neutral position and any changes are noted. If any change is noted the patient is followed up it is reverted back to normal and the duration for it is noted. The study is discontinued after the MPG grade reverts to the preoperative grade. The MPG grade is evaluated by a resident not involved in the study.