TITLE: Intravenous Jugular Catheterization for Rats
AUTHORS: Sharona Sedighim, Lani Tieu, Olivier George

[DESCRIPTION]
<div class = "text-blocks"><div class = "text-block">This protocol outlines the step-by-step setup and procedure of the pre-op, surgery, and post-op for intravenous jugular cathetarization for rats in intravenous self-administration studies (e.g. cocaine, oxycodone).</div></div>

[STEPS]
?. [Animal Preparation for Surgery]
Place rat in the knock-down chamber. Set isoflurane vaporizer dial on 5 to begin anesthetizing rat.
?. [Animal Preparation for Surgery]
Once breathing is constant (about 2 breaths every 3 seconds) and deep, turn off isoflurane and take the animal out for preparation.
?. [Animal Preparation for Surgery]
Shave the back from above the legs to just below the arms. CAREFULLY shave the neck on the right (unless stated otherwise).
?. [Animal Preparation for Surgery]
Scan the rat and check its RFID to ensure it is the correct rat.
?. [Animal Preparation for Surgery]
Weigh the rat and record its weight in surgery log.
?. [Animal Preparation for Surgery]
Place animal back into the knock-down chamber. Turn the isoflurane up to 3 if there is a long wait to be operated. Turn isoflurane to 5 if the surgeon is almost done/ready.
Monitor the rat's breathing when it is under isoflurane. Overexposure can cause death during surgery.
?. [Surgery Procedure]
Take the rat from the induction chamber and place it on the surgery table. Place its nose in the nose cone and put the nose cone valve (orange) in the downward position to deliver isoflurane.
Make sure the rat is completely anesthetized before doing eye bleeds or making an incision. Breathing should be deep, slow, and constantCan check by pinching between the toes, and making sure the rat doesn’t resist
?. [Surgery Procedure]
Clean the rat's neck with an alcohol prep pad.
?. [Surgery Procedure]
Make a small incision (about 2 cm) on the neck where you see the vein beating under the skin.
?. [Surgery Procedure]
Use sharp forceps to carefully dig through the muscle/tissue until you locate the jugular vein. The vein will look purple.
?. [Surgery Procedure]
Strip/clean the jugular vein of all attached tissue. Want it to be clean so you can penetrate it easily. When you’re done, flush the vein with saline to keep it moist and cover the incision site with gauze.
?. [Surgery Procedure]
Flip the animal over so that the back is facing you. Clean the back with an alcohol prep pad, and try to clean any loose hairs off. Make an incision large enough for the catheter to fit into (about 3-4 cm) on the lower back near above the legs.
?. [Surgery Procedure]
Using blunt scissors, start blunt dissecting at the back incision and move towards the neck incision. Poke a hole through the neck incision with the scissors, creating a passageway from the back to the neck.
?. [Surgery Procedure]
Place the hemostat clamps through the neck incision with the ends sticking out of the back incision, and remove the blunt scissors. Gently rest the hemostats off the rat.
?. [Surgery Procedure]
Test the catheter to make sure there are no leaks.
?. [Surgery Procedure]
Grab the end of the catheter tubing with the hemostats, and pull the tubing through the pocket until it comes out of the neck.
?. [Surgery Procedure]
Push the catheter into the body (can use hemostats to help). Align the catheter in the center of the rat (not too high on the shoulders and not to low on the back).Using a blade, poke a hole large enough for the catheter threading to go through. Clean the catheter port, attach the flusher, and make sure the catheter can be flushed.
When pushing the catheter through the skin, make sure you place fingers under the catheter.
?. [Surgery Procedure]
Flip the rat back so the neck is facing you. Flush the open skin with saline.
?. [Surgery Procedure]
Find the jugular vein again, and then isolate it by placing the metal stick underneath it.
?. [Surgery Procedure]
Cut a piece of black suture thread, fold it in half, and put it under the vein. Cut the thread at the folded part so that it becomes 2 pieces. Place one piece of the thread above the vein, the other piece below the vein.
?. [Surgery Procedure]
Bevel the catheter tubing so that it has a sharp edge. The sharp edge will allow the tubing to enter the vein more easily.
?. [Surgery Procedure]
Take a 20 gauge (black) needle and carefully make a hole in the vein, being sure to not go through the vein. Once you are in the vein, gently move the needle very slightly in and out and/or twist it, then pull the needle out.
?. [Surgery Procedure]
Place canoe tip into the hole that you just made in the vein. Use sharp forceps to grab the end of the catheter tubing.Using the canoe for guidance, slowly slide the tubing into the vein with the tip of the bevel facing down.
The canoe is optional. Use whatever method is helpful for you to get the tubing in the vein.
?. [Surgery Procedure]
Slide the catheter tubing in until you reach the bubble. Pull back blood with the flusher to ensure that the tubing is in the vein. If you do not see blood or if you feel resistance when you try to pull back blood with the flusher, then the tubing is not in the vein.
Twist the tubing inside the vein carefully to help with the flow.
?. [Surgery Procedure]
Once the tubing is in the vein (up to the bubble) and blood flow is good, tie the top suture above the bubble and the bottom suture below the bubble.
Make sure the knots are not too tight (will cut off flow of the catheter) or too loose (can release the catheter from the vein) Make sure to tie at least 3 knots for each suture
?. [Surgery Procedure]
Anchor the sutures onto the surrounding muscle using the suture needle. Test the flow of the catheter with flusher again to make sure it is still good.Cut the excess string.
?. [Surgery Procedure]
Tuck in any extra catheter tubing into the neck pocket. Check the flow of the catheter again and make sure the tubing did not get kinked.
?. [Surgery Procedure]
If flow is good, pass the rat off to the prep team for post-op, and note how to operation went in the surgery log. Sterilize tools before operating on the next rat.
?. [Post-operation]
Close catheter port with a hoodsie and metal cap.
When placing hoodsie on, do not press down on the back.
?. [Post-operation]
Slide your fingers down the rat's back to the incision site to bring any pockets of air out from under the skin.Vetbond the incision site to close it, then gently tug the skin apart to make sure it is completely closed and there is no blood coming out.
?. [Post-operation]
Flip the rat over and close the neck incision with vetbond. Gently tug the skin apart to make sure it is completely closed and there is no blood coming out.
?. [Post-operation]
With a 25 gauge needle (blue), give the rat point-bodyweight intramuscular injection of Cefazolin to the right leg.
?. [Post-operation]
With a 25 gauge needle (blue), give the rat point-bodyweight subcutaneous injection of Flunixin between the shoulders.
?. [Post-operation]
Place the rat in the recovery box. Write down how the animal is recovering in the surgery log.
No more than 2 rats should be in the recovery box at the same time.
?. [Post-operation]
When the rat wakes up and appears to be active (walking, climbing, exploring, etc.), place the animal back in its home cage and put a POST-OP sticker on the cage card with date of surgery and type of procedure (i.e. IV catheter).