Evaluation of the effect of Body Mass Index on the characteristics of spinal anaesthesia .

After the approval from the ethical committee and taking written consent from 61 patients who are undergoing elective surgery under spinal anaesthesia and who fulfilled inclusion and exclusion criteriawill be included for the surgery.Baseline data like age ,sex, height, weight and BMI of the patient will be recorded. Standard pre-anaesthetic assessment will be performed.For every patient transferred to the induction room , an intravenous line will be secured ,IV fluids started and standered ISA monitors attached

 A 23 guage quinke needle will be inserted into the subarchnoid space at the L2-L3 level and 3ml of 0.5% bupivacaine heavy will be injected after confirmation of free flow of CSF. NIBP,SPO2 and heart rate will be recorded every five minutes for first thirty minutes and every ten minute till the end of the surgery. Cold swab test will be performed to assess the onset of sensory blockade and will be considered when T10 level is achieved and duration of sensory block will be determined by 2 segment regression. Modified bromage scale [0-Full movements of legs and feet 1-Inability to raise extended leg;able to move knees and feet 2-Inability to raise extended leg and move knee;able to move feet 3-Complete block of motor function in lower limbs ] will be used to assess the onset of motor block in the patient and duration of motor block will be assessed postoperatively and noted