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Before setting up the equipment, decide where you want to give the fluids. To prevent your cat from escaping, choose a small enclosed space like a bathroom. This area should be free of distractions and away from children and other pets. To give subcutaneous fluids, you will need a fluid bag, fluid line, and a needle. Your vet will probably provide you with these supplies. The fluid bag and fluid line will be sealed in their own plastic protective coverings. Carefully remove this covering.  Look at the color of the fluid. It should be clear. If it’s discolored and cloudy, do not use the bag. Discolored fluid could indicate contamination.  The fluid line will have a roller clamp. Roll the clamp so the fluid line is squeezed together at the clamp. This will keep fluid from flowing through the line when you don’t want it to. The top end of the fluid line will have a large spike that will go into the fluid bag’s bottom opening. Remove the spike’s rubber covering and insert the spike into the fluid bag. Do not let the spike touch anything before you insert it. Give the spike a twist to ensure it fits snugly in the fluid bag. The top of the fluid line has a drip chamber that allows you to see how fast the fluid is flowing. Squeeze the fluid bag until the chamber is about halfway full. The fluid will flow more easily when it's free of air bubbles. To run fluid through the line, remove the protective cover off the bottom of the fluid line. Loosen the roller clamp and watch the fluid run through the line and out the bottom opening.  Do not allow anything to touch the fluid line's bottom opening. This is where the needle will go.  Position the fluid line by a sink or trash can so the fluid doesn’t get on the floor. Close the roller clamp after a few seconds so you don’t waste too much fluid.  Fortunately, air bubbles won’t hurt your cat. Don’t worry if you don’t get all the air bubbles out, but minimize them as much as you can. The bottom of the needle (where it attaches to the fluid line) may have a plastic covering. Remove this covering if present, and attach the connecting piece on the needle to the bottom opening of the fluid line. The needle will have another covering protecting its top end (the actual needle that is injected under the skin). Do not remove this covering until you’re ready to start giving the fluids. The fluid bag will need to hang about three feet above your cat. If you do not have an IV pole, you can slide the top hole of the fluid bag onto a coat hanger. Hang the coat hanger over the top of a door or, if you’re in a bathroom, the shower curtain rod.
Choose a location to give the fluids. Remove the protective packaging. Attach the fluid line to the bag. Fill the drip chamber about halfway. Run fluid through the line. Attach a new needle. Hang the fluid bag.