Comparison of ketamine to propofol in 1:2 versus 1:4 ketofol admixture on peri-intubation hemodynamics in exploratory laparotomy:a randomised comparative double blind clinical trial

Preoperatively , a quick assessment would be made. In the OT, vital monitors will be attached ,iv fluids started and injection glycopyrrolate 0.2mgiv will be given.

Baseline blood pressure will be recorded as an average of three consecutive readings with difference <10% in the systolic blood pressure.

During preoxygenation, iv. Midazolam 0.04 mg/kg  will be given. Study drug will be injected over 30 seconds, dose titrated till predefined end point is reached. The end point would be loss of verbal response and loss of eyelash reflex. Succinylcholine 2 mg/kg will be given and trachea intubated. The whole procedure would be completed in 60 seconds. From the beginning of induction till confirmation of endotracheal tube placement by confirming bilateral air entry, the cricoid pressure would be applied.

The intubation conditions will be graded by the same anaesthetist who performed intubation. The assessment would  include  1- ease of laryngoscopy (easy: jaw relaxed, no resistance to blade insertion; fair: jaw not fully relaxed, slight resistance to blade insertion; difficult: poor jaw relaxation, active resistance of the patient to laryngoscopy), 2- vocal cord position (easy: abducted; fair: intermediate/moving; difficult: closed), and 3- reaction to insertion of the tracheal tube and cuff inflation (Diaphragmatic movement/coughing) (easy: none; fair: one to two weak contractions or movement for less than 5 seconds; difficult: more than two contractions and/or movement for longer than 5 seconds).

The intubation condition will be graded as excellent if all criteria are excellent, good if all criteria are either excellent or good, or poor if any criterion is graded as poor.

If after 3 attempts, intubation is unsuccessful, Proseal LMA will be inserted and case excluded from study.

An episode of hypotension (decrease in MAP > 20 % from baseline) will be  immediately managed by norepinephrine starting with  5µg/min infusion (Norepinephrine 80µg/ml) and titrated to MAP. At the end of 1 hour of intubation, the amount of norepinephrine consumed in either group will be noted and, if further required, continued while titrating with MAP.