After the lecture on the history of anesthesia, each group of two students will receive an anesthetized rat. Read the procedures in your lab manual on pages 22-28 (Utilization of Albino Rats). You will not do steps 1-3, but you should understand how to calculate and administer anesthesia. The purpose of this lab is to allow you to become familiar with the stages of anesthesia, so that you will be able to recognize surgical anesthesia. This lab will also prepare you for the surgery you will perform for Exercise #3, next week. You will not do an experiment today, so take your time and make sure you get the surgical techniques down. Read the experimental procedure for Exercise #3 on pages 31-33, so you will understand the purpose of the surgical procedures.ReturnYour rat was anesthetized intraperitoneally using Nembutal (an injectable barbiturate). Make sure you know how to calculate the dosage that was given before you leave today.
Once you receive your rat, return to your lab table and place him on the rat board. Make sure the rat is lying on the surgical board ventral side up with its nose pointed toward the anterior end of the board (so that you are looking at the underside of its neck). If the rat is not positioned in this manner, the airway could easily become blocked and the animal will suffocate. The techniques you need to perform are cannulation of the urinary bladder and cannulation the iliac vein. Since there are two iliac veins, each student should attempt this procedure. To determine if the animal is in the stage of surgical anesthesia, you should look for several signs. Is respiration quick or slow? Are the respiratory movements high in the chest or are they abdominal? Does the animal respond by blinking if you tap gently near the corner of its eye with a blunt probe? Does the animal respond to pedal stimulation (pinch the toes with hemostats)? Have a T. A. double check to make sure before beginning your surgery.