EAQ Week 3 Math

A health care provider prescribes cefazolin sodium 375 mg intravenous piggyback (IVPB) every 8 hours. The vial of powder contains 500 mg of the medication. This must be reconstituted with 2 mL of 0.9% sodium chloride. In the resulting solution 1 mL contains 225 mg of cefazolin. How many mL of cefazolin solution will the nurse administer for one dose? Record your answer using one decimal place.

1.7 mL 375/225x1 = 1.7

Question 32 of 50 Intravenous (IV) fluid replacement of 7200 mL during the first 24 hours has been prescribed for a client with severe burns. Fifty percent of fluid replacement will be administered in the first 8 hours; then the remaining 50% given over the next 16 hours. How many milliliters per hour will the nurse infuse during the first 8 hours? Record your answer using a whole number. mL/h

Rationale Fifty percent of the total volume to be infused is 3600 mL (7200/2 = 3600). The total time of infusion for this volume is 8 hours. 3600 mL/8 hours = 450 mL/h.

Question 35 of 50 The nurse has 100 units regular insulin in 100-mL normal saline for infusion. There is a prescription to calculate the infusion rate based on the client's glucose levels using the formula: Glucose mg/dL ÷ 100 = units/h. The client's glucose level is 350 mg/dL. The insulin will need to infuse at how many milliliters per hour? Record your answer using one decimal place. mL/h

Rationale The client's glucose = 350 mg/dL. 350 ÷ 100 = 3.5 units/h. The pharmacy dispensed 100 units regular insulin in 100 mL normal saline. 100/100 = 1:1 ratio. Therefore 3.5 units/hour = 3.5 mL/h.

Question 27 of 50 An intravenous piggyback (IVPB) of cefazolin 500 mg in 50 mL of 5% dextrose in water is to be administered over a 20-minute period. The tubing has a drop factor of 15 drops/mL. The nurse regulates the infusion to run at how many drops per minute? Record your answer using a whole number. Do not include units in your answer. gtt/minute:

That' s right! Rationale Using dimensional analysis, the rate in drops per minute (gtt/min) can be calculated like this: 50 mL/20 min × 15 gtt/mL = (50 × 15)/20 = 750/20 = 75/2 = 37.5 gtt/min. 38 with no units. Because drops cannot be accurately measured as fractions in most clinical settings, rounding will be necessary; therefore 37.5 gtt/min=38 gtt/min. Test-Taking Tip: When taking the NCLEX exam, an on-screen calculator will be available for you to determine your response, which you will then type in the provided space.

Intravenous azithromycin 10 mg/kg is prescribed for a toddler who weighs 33 pounds. A vial containing 300 mg of the powdered form of the medication must be reconstituted with 3.8 mL of sterile water to yield a volume of 4 mL. How many milliliters of reconstituted medication will the nurse add to the intravenous piggyback solution? If rounding is necessary, record your answer using one decimal place. Do not include units in your answer.mL

Rationale The nurse is adding a prescribed dosage of reconstituted medication to an intravenous piggyback solution for infusion. The prescribed medication is 10 mg/kg. Add the volume of sterile water (3.8 mL) and the powdered medication displacement volume (0.2 mL) to get the total volume (4 mL) in the reconstitution vial. The available concentration is 300 mg/4 mL. Now the volume of reconstituted medication can be calculated in three different ways to get the correct answer. Given: Child's weight in kg = 33 lb × 1 kg/2.2 lb = 15 kg Prescribed dose: 15 kg × 10 mg/kg = 150 mg

Question 38 of 50 A client is receiving heparin sodium intravenously at 1500 units/h. The concentration in the bag is 25,000 units/500 milliliters. How many milliliters will infuse during the nurse's 8-hour shift? Record your answer using a whole number. So close! Rationale The prescribed rate is 1500 units/h. The available concentration is 25,000 units in 500 mL. Make the necessary conversions and use dimensional analysis to determine the appropriate rate in mL/h. The ratio and proportion method is not appropriate for this situation.

So close! Rationale The prescribed rate is 1500 units/h. The available concentration is 25,000 units in 500 mL. Make the necessary conversions and use dimensional analysis to determine the appropriate rate in mL/h. The ratio and proportion method is not appropriate for this situation. 1500u / 50 = 30ml 30ml x 8 hour shift = 240 ml

Question 25 of 50 A client requires intravenous fluids postoperatively. The health care provider has prescribed 5% dextrose in water (D W) to infuse at 125 mL/h. To deliver the solution at the correct drip rate, which information would the nurse require to calculate the rate? The total fluid volume in the bag does not determine the drip rate.

So close! Rationale Knowing the number of drops per milliliter delivered by the infusion set is necessary to calculate the drip rate of an intravenous infusion. The diameter of the tubing being used does not determine the drip rate, only the size of the drop. The size of the needle or catheter in the vein does not determine the drip rate. Different infusion sets deliver different, preset numbers of drops per milliliter. Test-Taking Tip: Many times, the correct answer is the longest alternative given, but do not count on it. Item writers (those who write the questions) are also aware of this and attempt to avoid offering you such helpful hints.