HESI RN
RN Hesi Med Surg Dosage Calculations Questions
Extract:
Question 1 of 5
Dobutamine hydrochloride 2 mcg/kg/min is prescribed for a client weighing 165 pounds. The solution is mixed with 50 mg of dobutamine In 1,000 mL of DW. The nurse should set the Infusion pump to deliver how many mL/hour? (Enter numeric value only.)
Correct Answer: 180
Rationale: Weight: 165 / 2.2 = 75 kg. Dose: 2 mcg/kg/min × 75 = 150 mcg/min × 60 = 9000 mcg/hour. Concentration: 50 mg = 50000 mcg / 1000 mL = 50 mcg/mL. Volume = 9000 / 50 = 180 mL/hour.
Question 2 of 5
The healthcare provider prescribes lamivudine oral solution 150 mg twice daily for a client who is HIV positive. The available bottle contains 240 mL of lamivudine labeled, '10 mg/mL.' How many mL should the nurse administer in a 24 hour period? (Enter numeric value only.)
Correct Answer: 30
Rationale: Dose per administration: 150 mg / (10 mg/mL) = 15 mL. Daily volume: 15 × 2 = 30 mL.
Question 3 of 5
The healthcare provider prescribes amoxicillin 500 mg every 8 hours for a child who weighs 88 pounds. The recommended maximum safe dose is 50 mg/kg/24 hour. The available suspension is labeled, Amoxicillin Suspension 250 mg/5 mL. Based on this child weight, how many mL should the nurse administer? (Enter numerical value only. (If rounding is required, round to the whole number.))
Correct Answer: 10
Rationale:
To determine the volume to administer, first convert the child's weight from pounds to kilograms: 88 pounds × 0.454 kg/pound = 39.952 kg (rounded to 40 kg). The safe dose is 50 mg/kg/24 hours, so 50 × 40 = 2000 mg/day. The prescribed dose is 500 mg every 8 hours, or 500 × 3 = 1500 mg/day, which is safe. The suspension is 250 mg/5 mL. Set up a proportion: 250 mg / 5 mL = 500 mg / x mL. Solving, x = (500 × 5) / 250 = 10 mL.
Question 4 of 5
A client returns from the PACU with a bag of IV fluids that has 630 mL remaining in the 1,000 mL bag. The prescription reads, 'Continue the present IV over the next 7 hours.' The IV administration set delivers 10 gtt/mL. The nurse should regulate the infusion to deliver how many drops/minute to accomplish the new prescription? (Enter numeric value only.)
Correct Answer: 15
Rationale: Flow rate = (630 mL × 10 gtt/mL) / (7 × 60) = 15 gtt/min.
Question 5 of 5
A client is brought to the emergency center for fluid replacement after running a marathon, and the healthcare provider prescribes a 500 mL bolus of 0.9% normal saline to be administered over 4 hours. The Infusion set delivers 10 gtt/mL, so the nurse should regulate the Infusion to deliver how many gtt/minute? (Enter numerical value only. If rounding is required, round to the nearest whole number.)
Correct Answer: 21
Rationale: Infusion rate: 500 mL / 4 hours = 125 mL/hour. Flow rate: (125 × 10) / 60 = 20.833 gtt/min, rounded to 21.