ANSWERS

1. Ideally, what is the maximum period of time that an intravenous catheter may remain indwelling?
   48 Hours.
2. What is a "cut down"?
   A small skin incision adjacent to the chosen vein for fluid therapy to allow improved visualisation. Other advantages of this procedure include reduced risk of bacteraemia and the decreased likelihood of the catheter kinking.
3. What is used to flush an intravenous catheter in the event of a blockage?
   Heparinised saline (1:1000 Heparin). 4 units per ml.
4. What is the rate in drops/ml of a standard fluid administration set (giving set)?
   15 or 20 drops/ml.
5. What type of fluid administration set is preferred for smaller patients and why?
   A paediatric giving set. This delivers fluid at a rate of 60 drops/ml and allows greater accuracy in the administration of smaller volumes of fluid, or use of an infusion pump.
6. What is a Burette giving set?
   A fluid administration set with an integral measuring device to allow accurate infusion of small volumes of fluid.
7. You are monitoring a restless bull terrier on intravenous fluid therapy. What methods could be employed to prevent interference with the equipment.
   • Elizabethan collar to discourage chewing of the dressing and giving set.
   • A sock impregnated with bitter spray placed over the catheter dressing.
   • Splinting the catheterised limb. This helps to prevent occlusion of the giving set when the patient lies down.
   • Use of a coiled giving set which is less likely to become kinked if a patient is moving around.
8. Why are over-the-needle catheters preferable to butterfly needles?
   Butterfly needles are only suitable for short-term use, since the needle tip may damage the vein. Possible complications include thrombophlebitis, extravasation and thrombosis. Over-the-needle catheters consist of a stainless steel needle, which is used to guide the pliable outer catheter into the vein. The needle is removed following placement. There is significant less risk due to the soft nature of the catheter, and this is more comfortable for the patient.
9. Why should a dressing covering an indwelling intravenous catheter be removed and replaced regularly?
   • Sterility is essential to avoid sepsis; therefore the dressing should always be scrupulously clean and dry.
   • Checks for irritation and peripheral oedema around the vein are vital.
10. What precaution should be taken if only 500mls of a litre bag of fluids are to be administered?
    Predetermine the level at which fluid administration should cease and place marker tape horizontally around the bag to establish this. This is used as a failsafe measure after calculating the time taken for the correct volume of fluid to be administered to the patient.
11. What is a constant rate infusion pump?
    An accurate mechanical device which allows precise timed delivery of a calculated volume of fluid. Two basic types are available: a wheel pump or syringe driver.
12. To what temperature should fluids be warmed before administration?
    Body temperature (approximately 38° C).

A practical task: Set up equipment for intravenous fluid therapy accompanies this module.