Wearing nonsterile gloves locate the interspace between L3-L4 and mark the location with the nail of your thumb or create a small indentation with an object like pen or needle cap. Open the spinal tray, wear sterile gloves, facemask, and protective gear and prepare the equipment. Draw the lidocaine into the 10-mL syringe. Clean the skin in a circular motion with skin swabs and antiseptic. Place a sterile drape should be placed beneath the patient, and a fenestrated drape should be placed over the patient. Raise a skin wheal with the 25-gauge needle, then anaesthetize the deeper tissue with the longer 20-gauge needle. Insert the needle all the way to the hub, aspirate to make sure it's not in a blood vessel, and then inject a small amount as the needle is pulled back a few centimeters. Carry on in this manner above, below, and to the sides.