Ch. 5 Dosage Calculation of IV Solutions and Drugs

Which drop factor allows the greatest volume of intravenous fluid to be delivered per hour at a drip rate of 50 gtt per minute? a. 10 b. 15 c. 20 d. 60

ANS: A A drop factor of 10 means that 10 gtt equal 1 mL. At a drip rate of 50 gtt/min, a drop factor of 10 delivers 5 mL/min or 300 mL/h. At a drip rate of 50 gtt/min, a drop factor of 15 delivers 3.3 mL/min or 188 mL/h. At a drip rate of 50 gtt/min, a drop factor of 20 delivers 2.5 mL/min or 150 mL/h. At a drip rate of 50 gtt/min, a drop factor of 60 delivers 0.8 mL/min or 50 mL/h.

Under which conditions should a microdrip setup for an IV infusion always be used? a. When the patient is an infant b. When whole blood is to be infused c. When the patient has only a few veins available for infusion d. When a very large amount of fluid needs to be infused quickly

ANS: A An infant has a small normal fluid volume and an IV that runs in too fast can cause fluid overload, sometimes with heart failure. Using a microdrip setup helps prevent a too rapid infusion rate.

What does the term infiltration mean? a. Leakage of intravenous fluid into the surrounding tissue b. Infusion of intravenous fluids at a faster rate than was prescribed c. Plugging up or clotting off the needle during intravenous infusion d. Infusion of intravenous fluids without the use of a pump or controller

ANS: A The definition of infiltration is a condition in which an IV needle or catheter pulls from the vein and leaks IV fluids into the surrounding tissue, resulting in tissue swelling. An infusion of IV fluids faster than prescribed is a "runaway" IV. Plugging or clotting of a needle has no specific name. Infusion of fluids without a pump or controller is a manually controlled infusion.

A patient is to receive 125 mL of intravenous fluid per hour and the drop factor is 10 gtt/mL. You count the 15-second drip rate to be 8 gtt/min. What is your best action? a. Nothing, the IV flow rate is correct. b. Turn the rate down to 5 gtt/15 s. c. Turn the rate up to 11 gtt/15 s. d. Turn the rate up to 15 gtt/15 s.

ANS: B At 125 mL/h, the patient should receive 2 mL/min (125 mL/60 minutes). With a drop factor of 10 gtt/mL, the total number of drops per minute should be 20. The 15-second drop rate should be 5 (20 gtt/min/4).

How is extravasation different from infiltration? a. Infiltration occurs in the hand, whereas extravasation occurs in the arm. b. Both conditions lead to swelling, but extravasation causes tissue damage. c. Infiltration is swelling accompanied by pain, whereas extravasation is not painful. d. Extravasation causes phlebitis along with tissue swelling, whereas infiltration causes fluid overload along with swelling.

ANS: B Both conditions result from leakage of fluid out of the vein and into surrounding tissues. Infiltration, although uncomfortable, does not result in tissue damage. Extravasation results directly or indirectly in tissue damage. If the damage is severe enough, tissue can become necrotic and slough.

What is the most important advantage for intravenous (IV) infusion of drugs? a. Anyone can administer IV drugs. b. The drug reaches the bloodstream immediately. c. Drugs given intravenously cost less than drugs given orally. d. The patient is not required to be alert to swallow the drug.

ANS: B Drugs administered by IV infusion are immediately in the bloodstream and reach their target tissues fastest. This means that both the drug benefits (intended actions) and any adverse actions can happen more quickly. IV drugs tend to cost more than oral drugs. Although the patient does not have to be alert to receive IV drugs, it is not their main advantage. Administering IV drugs can only be performed by a skilled health care provider.

While examining a patient's peripheral intravenous (IV) site, you observe a red streak along the length of the vein. On palpation, the vein feels hard and cordlike. What is your best action? a. Check for a blood return and notify the prescriber. b. Discontinue the infusion and remove the IV needle. c. Apply ice packs to the vein and continue the infusion. d. Change the IV fluid to normal saline and redress the site.

ANS: B Phlebitis is an inflammation of the vein. Its presence in a vein being used for IV therapy may be caused by mechanical forces associated with the IV device or by chemical factors related to the composition and osmolarity of the drug solution. The key manifestation is that the symptoms are directly associated with the vein. The vein with phlebitis should not receive any additional fluids and the IV therapy is discontinued. If IV therapy needs to continue, it is restarted in a different vein.

On an infusion pump, what does the abbreviation "VTBI" indicate? a. Amount of fluid already infused b. Amount of fluid remaining in the bag or bottle c. Total amount of fluid prescribed for the day d. How fast the infusion should be run

ANS: B The abbreviation VTBI stands for volume to be infused. It is the amount remaining in an IV bag that has not yet been infused.

A patient is to receive 1000 mL intravenously of dextrose 5% in lactated Ringer's solution in 8 hours. When you check the intravenous (IV) bag after 2 hours, 700 mL remain in the bag. How many milliliters have already infused? a. 100 b. 300 c. 700 d. 1000

ANS: B The amount infused is equal to the starting amount (1000 mL) minus the amount remaining in the IV bag or other container (700 mL). 1000 - 700 = 300 mL have infused.

A patient is receiving an intravenous (IV) infusion of 1000 mL normal saline solution containing 60 mEq/L of potassium chloride over 6 hours. How many mEq of potassium chloride are delivered per 10 mL of this solution? a. 0.06 b. 0.6 c. 6 d. 60

ANS: B The amount of potassium is evenly distributed throughout the 1000 mL. Thus the potassium amount is proportional. 60 mEq are in 1000 mL, 6 mEq are in 100 mL, 0.6 mEq are in 10 mL, and 0.06 mEq are in 1 mL.

A patient's IV is supposed to have a drip rate of 42 gtt/min. You count 8 gtt in 15 seconds. What is your best action? a. Nothing, the IV flow rate is correct. b. Increase the drip rate to 10 gtt/15 seconds. c. Increase the drip rate to 15 gtt/15 seconds. d. Decrease the drip rate to 6 gtt/15 seconds.

ANS: B The flow rate is incorrect. With 8 gtt in 15 seconds, the drops per minute are only 32. The drip rate must be increased to 10 gtt in 15 seconds to achieve a drip rate of 42 gtt/min. At 15 gtt/15 seconds, the drip rate would be 60 gtt/min. At 6 gtt/15 seconds, the drip rate would be 24 gtt/min.

An IV infusion order for a patient reads "1000 mL dextrose 5% in normal saline intravenously, immediately." What additional information does the prescriber need to provide for it to be a valid order? a. Drip rate b. Drop factor c. Duration d. Start time

ANS: C A valid intravenous (IV) therapy order must include the duration of infusion. The word "immediately" in this prescription refers to when the IV infusion is to start, not its duration.

What sign or symptom is an indication of IV extravasation? a. Fever b. Purulent drainage c. Pain at the infusion site d. Strong blood return when the IV bag is positioned below the level of the IV site

ANS: C Fever and purulent drainage indicate infection. A strong blood return indicates the IV needle or catheter is in the blood vessel. With extravasation, the needle or catheter is not in the blood vessel. Fluid then leaks into the surrounding tissue and often causes pain in those tissues.

Which precaution is most important to teach a patient who is receiving intravenous (IV) drug therapy? a. "Turn on your call light if the IV machine starts to beep for any reason." b. "Do not use the arm that has the IV running in it for any reason whatsoever." c. "Call me immediately if you start to feel any pain or burning in the arm with the IV." d. "If you think the IV is running too slowly, just push the up-arrow button on the machine once or twice."

ANS: C Pain and burning at the site are indicators of infiltration and extravasation. These indicators must be investigated as soon as they start to prevent tissue damage. Although it is helpful for the patient to alert someone that the machine is beeping, it is not the most important precaution. The patient should never be told to adjust the flow rate. Depending on the specific location of the needle, the arm with the IV can be used gently.

How many drops per milliliter (mL) does a microdrip chamber and tubing provide? a. 15 b. 20 c. 60 d. 100

ANS: C The universal drop factor for a standard microdrip chamber is 60 gtt/mL by all manufacturers.

Which term describes how much fluid is to be infused intravenously? a. Rate b. Infusion c. Volume d. Duration

ANS: C The volume is the amount to be infused. The rate is the speed of the infusion. The infusion is just the term used to describe the act of running IV fluids into a blood vessel. The duration is how long in minutes or hours an IV infusion is order to run.

What will the drip rate of an intravenous infusion with a drop factor of 20 need to be in order to deliver 1000 mL in 8 hours? a. 13 gtt/min b. 31 gtt/min c. 42 gtt/min d. 60 gtt/min

ANS: C To deliver 1000 mL over 8 hours, 125 mL must be delivered per hour or 2.08 mL/min. 2.08 mL/min times 20 gtt/mL equals 41.6 gtt/min, round up to 42.

The intravenous (IV) site of a patient who has been receiving IV therapy for 2 days is red and has a small amount of pus oozing from around the needle. What is your action? a. Document the finding as an expected response to long-term IV therapy as the only action. b. Immediately notify the prescriber to get an order to discontinue the IV therapy. c. Use an iodine solution to clean the site and replace the dressing. d. Discontinue the IV therapy and notify the prescriber.

ANS: D An infected infusion site is an indication to immediately discontinue the IV therapy. An order is not needed under these circumstances, but the prescriber should be notified.

What is the hourly flow rate for 250 mL of normal saline to be administered over 2 hours? _____ mL/h

ANS: 125 The patient should receive 125 mL/h (250 mL/2 hours = 125 mL).

A patient is to receive 100 mL of normal saline over the next 5 hours with microdrip tubing. How many drops per minute are required to infuse this fluid in the prescribed time? _____ gtt per minute

ANS: 20 The flow rate for 100 mL over 5 hours is 20 mL/h (100 mL/5 hours). With microdrip tubing, the drop factor of 60 gtt/mL is the same as the number of minutes in 1 hour (60). The two sets of 60 cancel each other out, and the flow rate for microdrip tubing always equals the drop rate. So, 20 mL/h by microdrip tubing = 20 gtt/min.

A patient is to receive 1000 mL of D5W intravenously over 6 hours. The tubing set has a drop factor of 15 gtt/mL. How many drops per minute are needed to infuse this fluid in the prescribed time? _____ gtt per minute

ANS: 42 1000 mL in 6 hours = 167 mL/h (1000/6 = 166.6 mL, round up to 167). 2.8 mL/min (167 mL/60 minutes = 2.78 mL, round up to 2.8 mL/min); 42 gtt/min (2.8 mL × drop factor of 15 = 42 gtt/min).

Which problem is a major disadvantage of an intravenous (IV) pump? a. The alarms are so sensitive that nurses tend to ignore them when they sound frequently. b. Patients and families can override the automatic features and reset the infusion rate. c. It can "run away" and cause a patient to experience fluid overload. d. It can continue to push fluid into the tissue when infiltration occurs.

ANS: D IV pumps push fluid into the patient at a rate greater than gravity and can continue to push even when resistance is increased. Infiltration or extravasation may not be detected by the machine until the situation is serious.

If an IV scheduled to have a duration of 6 hours is started at 5:00 p.m., what is the expected stop time? a. 5:00 a.m. b. 11:00 a.m. c. 1:00 a.m. d. 11:00 p.m.

ANS: D Six hours from 5:00 p.m. is 11:00 p.m. 5:00 a.m. would be 24 hours; 11:00 a.m. would be 18 hours; and 1:00 a.m. would be 8 hours.

How does the "drop factor" affect IV infusions? a. Fluid with a larger drop factor infuses more slowly than fluid with a smaller drop factor. b. Smaller drop factors occur with smaller needles (or cannulas) and larger drop factors occur with larger needles. c. The smaller the drop factor, the fewer the number of drops needed to administer 1 mL of infusion fluid. d. The larger the drop factor, the fewer the number of drops needed to administer 1 mL of infusion fluid.

ANS: D The drop factor is the number of drops (gtt) needed to make 1 mL of IV fluid. The larger the drop, the fewer drops needed to make 1 mL.