Practice Set 2 - Wrap-Up Challenge¶
Instructions¶
This set simulates a real clinical competency exam.
- Problems are in random mixed order with no topic labels
- Numbers are harder than Set 1
- No hints are given
- Attempt every problem before revealing the answer
- Aim for 90% or higher (23 out of 25 correct)
Challenge Yourself
Do not reveal answers until you have committed to your solution in writing. The goal is to identify gaps before clinical practice — not after.
Problem 1
Order: atenolol 12.5 mg orally Stock: 25 mg per tablet How many tablets?
Answer
Verify tablet is scored before splitting.
Problem 2
Order: 750 mL 0.9% NaCl over 6 hours What is the flow rate in mL/hr?
Answer
Problem 3
Order: tobramycin 2.5 mg/kg IV Patient weight: 198 lb Stock: 40 mg/mL How many mL?
Answer
Convert weight: [198 \cancel{\text{ lb}} \times \frac{1 \text{ kg}}{2.2 \cancel{\text{ lb}}} = 90 \text{ kg}]
Full chain: [\frac{90 \cancel{\text{ kg}}}{1} \times \frac{2.5 \cancel{\text{ mg}}}{1 \cancel{\text{ kg}}} \times \frac{1 \text{ mL}}{40 \cancel{\text{ mg}}} = 5.625 \text{ mL}]
Round to: 5.6 mL
Problem 4
Convert 0.375 g to mcg.
Answer
Problem 5
Order: clarithromycin 0.5 g orally Stock: 250 mg/5 mL How many mL?
Answer
Problem 6
Order: 500 mL over 35 minutes What is the flow rate in mL/hr?
Answer
Convert time: [35 \cancel{\text{ min}} \times \frac{1 \text{ hr}}{60 \cancel{\text{ min}}} = 0.583 \text{ hr}]
Rate: [\frac{500 \text{ mL}}{0.583 \text{ hr}} = 857.6 \text{ mL/hr}]
Round to: 858 mL/hr
Verify This Rate
Rates above 500 mL/hr are unusual. Verify the order before programming the pump.
Problem 7
Order: amoxicillin 30 mg/kg/day orally divided every 8 hours Patient: child weighing 16 kg Stock: 200 mg/5 mL How many mL per dose?
Answer
Total daily dose: [16 \cancel{\text{ kg}} \times \frac{30 \text{ mg}}{1 \cancel{\text{ kg}}} = 480 \text{ mg/day}]
Single dose (3 doses/day): [480 \div 3 = 160 \text{ mg per dose}]
Volume: [\frac{160 \cancel{\text{ mg}}}{1} \times \frac{5 \text{ mL}}{200 \cancel{\text{ mg}}} = 4 \text{ mL}]
Problem 8
Order: heparin 1800 units/hr IV Stock: 25,000 units in 250 mL 0.9% NaCl What is the flow rate in mL/hr?
Answer
Concentration: [\frac{25{,}000 \text{ units}}{250 \text{ mL}} = 100 \text{ units/mL}]
Flow rate: [\frac{1800 \text{ units/hr}}{100 \text{ units/mL}} = 18 \text{ mL/hr}]
Problem 9
A 1000 mL bag starts at 2130 running at 80 mL/hr. What time will it complete?
Answer
Infusion time: [\frac{1000 \text{ mL}}{80 \text{ mL/hr}} = 12.5 \text{ hr}]
Convert decimal: [0.5 \times 60 = 30 \text{ min}]
Completion time: [2130 + 12 \text{ hr } 30 \text{ min} = 1000 \text{ next day}]
Completes at 1000 the following morning.
Problem 10
Order: digoxin 0.125 mg orally Stock: 62.5 mcg per tablet How many tablets?
Answer
Problem 11
Order: 1000 mL Lactated Ringer's over 12 hours Tubing: 15 gtt/mL What is the drip rate in gtt/min?
Answer
Convert time: [12 \times 60 = 720 \text{ min}]
Calculate: [\frac{1000 \text{ mL}}{720 \text{ min}} \times 15 \text{ gtt/mL} = 20.8 \text{ gtt/min}]
Round to: 21 gtt/min
Problem 12
Order: morphine 0.08 mg/kg IV PRN Patient weight: 187 lb Stock: 5 mg/mL How many mL? Round to nearest hundredth.
Answer
Convert weight: [187 \cancel{\text{ lb}} \times \frac{1 \text{ kg}}{2.2 \cancel{\text{ lb}}} = 85 \text{ kg}]
Full chain: [\frac{85 \cancel{\text{ kg}}}{1} \times \frac{0.08 \cancel{\text{ mg}}}{1 \cancel{\text{ kg}}} \times \frac{1 \text{ mL}}{5 \cancel{\text{ mg}}} = 1.36 \text{ mL}]
Problem 13
Convert 4.5 L to mL.
Answer
Problem 14
Order: dopamine 8 mcg/kg/min IV Patient weight: 75 kg Stock: dopamine 800 mg in 500 mL D5W What is the flow rate in mL/hr?
Answer
Dose per minute: [75 \cancel{\text{ kg}} \times \frac{8 \text{ mcg}}{1 \cancel{\text{ kg}} \cdot \text{min}} = 600 \text{ mcg/min}]
Convert to mg/hr: [600 \cancel{\text{ mcg/min}} \times \frac{1 \cancel{\text{ mg}}}{1000 \cancel{\text{ mcg}}} \times \frac{60 \text{ min}}{1 \text{ hr}} = 36 \text{ mg/hr}]
Concentration: [\frac{800 \text{ mg}}{500 \text{ mL}} = 1.6 \text{ mg/mL}]
Flow rate: [\frac{36 \text{ mg/hr}}{1.6 \text{ mg/mL}} = 22.5 \text{ mL/hr}]
Round to: 23 mL/hr
Problem 15
Order: ibuprofen 10 mg/kg orally, max 400 mg Patient: child weighing 48 kg Stock: 100 mg/5 mL How many mL?
Answer
Calculated dose: [48 \cancel{\text{ kg}} \times \frac{10 \text{ mg}}{1 \cancel{\text{ kg}}} = 480 \text{ mg}]
480 mg exceeds max of 400 mg — use 400 mg
Volume: [\frac{400 \cancel{\text{ mg}}}{1} \times \frac{5 \text{ mL}}{100 \cancel{\text{ mg}}} = 20 \text{ mL}]
Problem 16
A 750 mL bag started at 0730 running at 125 mL/hr. It is now 1130. How much fluid remains and what time will the infusion complete?
Answer
Time elapsed: [1130 - 0730 = 4 \text{ hr}]
Volume infused: [125 \text{ mL/hr} \times 4 \text{ hr} = 500 \text{ mL}]
Volume remaining: [750 - 500 = 250 \text{ mL}]
Time remaining: [\frac{250 \text{ mL}}{125 \text{ mL/hr}} = 2 \text{ hr}]
Completion time: [1130 + 2 \text{ hr} = 1330]
Completes at 1330 (1:30 PM).
Problem 17
Order: vancomycin 20 mg/kg IV over 90 minutes Patient weight: 220 lb Stock: 500 mg/10 mL What is the total dose in mg and the flow rate in mL/hr?
Answer
Convert weight: [220 \cancel{\text{ lb}} \times \frac{1 \text{ kg}}{2.2 \cancel{\text{ lb}}} = 100 \text{ kg}]
Total dose: [100 \cancel{\text{ kg}} \times \frac{20 \text{ mg}}{1 \cancel{\text{ kg}}} = 2000 \text{ mg}]
Volume to infuse: [\frac{2000 \cancel{\text{ mg}}}{1} \times \frac{10 \text{ mL}}{500 \cancel{\text{ mg}}} = 40 \text{ mL}]
Convert time: [90 \cancel{\text{ min}} \times \frac{1 \text{ hr}}{60 \cancel{\text{ min}}} = 1.5 \text{ hr}]
Flow rate: [\frac{40 \text{ mL}}{1.5 \text{ hr}} = 26.7 \text{ mL/hr}]
Round to: 27 mL/hr
Problem 18
Order: gentamicin 6 mg/kg/day IV divided every 8 hours Patient weight: 66 kg Stock: 10 mg/mL How many mL per dose?
Answer
Total daily dose: [66 \cancel{\text{ kg}} \times \frac{6 \text{ mg}}{1 \cancel{\text{ kg}}} = 396 \text{ mg/day}]
Single dose (3 doses/day): [396 \div 3 = 132 \text{ mg per dose}]
Volume: [\frac{132 \cancel{\text{ mg}}}{1} \times \frac{1 \text{ mL}}{10 \cancel{\text{ mg}}} = 13.2 \text{ mL}]
Problem 19
Order: 500 mL over 4 hours Tubing: 10 gtt/mL What is the drip rate in gtt/min?
Answer
Convert time: [4 \times 60 = 240 \text{ min}]
Calculate: [\frac{500 \text{ mL}}{240 \text{ min}} \times 10 \text{ gtt/mL} = 20.8 \text{ gtt/min}]
Round to: 21 gtt/min
Problem 20
An IV is running at 40 mL/hr. Stock: heparin 25,000 units in 500 mL What dose is the patient receiving per hour?
Answer
Concentration: [\frac{25{,}000 \text{ units}}{500 \text{ mL}} = 50 \text{ units/mL}]
Dose rate: [40 \text{ mL/hr} \times 50 \text{ units/mL} = 2000 \text{ units/hr}]
Problem 21
Order: prednisolone 2 mg/kg/day orally divided every 12 hours Patient: child weighing 14 kg Stock: 5 mg/5 mL solution How many mL per dose?
Answer
Total daily dose: [14 \cancel{\text{ kg}} \times \frac{2 \text{ mg}}{1 \cancel{\text{ kg}}} = 28 \text{ mg/day}]
Single dose (2 doses/day): [28 \div 2 = 14 \text{ mg per dose}]
Volume: [\frac{14 \cancel{\text{ mg}}}{1} \times \frac{5 \text{ mL}}{5 \cancel{\text{ mg}}} = 14 \text{ mL}]
Problem 22
Order: morphine 4 mg/hr IV continuous Stock: morphine 100 mg in 500 mL 0.9% NaCl What is the flow rate in mL/hr?
Answer
Concentration: [\frac{100 \text{ mg}}{500 \text{ mL}} = 0.2 \text{ mg/mL}]
Flow rate: [\frac{4 \text{ mg/hr}}{0.2 \text{ mg/mL}} = 20 \text{ mL/hr}]
Problem 23
Order: 1000 mL over 10 hours After 6 hours only 500 mL has infused. 500 mL remains with 4 hours left. What rate is needed to complete on time? Is this within the 25% adjustment guideline?
Answer
Required rate: [\frac{500 \text{ mL}}{4 \text{ hr}} = 125 \text{ mL/hr}]
Original rate: [\frac{1000 \text{ mL}}{10 \text{ hr}} = 100 \text{ mL/hr}]
Percentage increase: [\frac{125 - 100}{100} \times 100 = 25\%]
Exactly 25% — at the limit of the guideline. Consult the prescriber before adjusting.
Problem 24
Convert 2 tbsp to mL then to L.
Answer
tbsp to mL: [2 \cancel{\text{ tbsp}} \times \frac{15 \text{ mL}}{1 \cancel{\text{ tbsp}}} = 30 \text{ mL}]
mL to L: [30 \cancel{\text{ mL}} \times \frac{1 \text{ L}}{1000 \cancel{\text{ mL}}} = 0.03 \text{ L}]
Problem 25
Safe dose range: 15-30 mg/kg/day Order: amoxicillin 20 mg/kg/day divided every 8 hours Patient: child weighing 27 kg Stock: 250 mg/5 mL Is the dose safe? If yes, how many mL per dose?
Answer
Minimum safe dose: [27 \text{ kg} \times 15 \text{ mg/kg} = 405 \text{ mg/day}]
Maximum safe dose: [27 \text{ kg} \times 30 \text{ mg/kg} = 810 \text{ mg/day}]
Ordered dose: [27 \text{ kg} \times 20 \text{ mg/kg} = 540 \text{ mg/day}]
540 mg/day is between 405 and 810 mg/day ✅ Dose is safe.
Single dose (3 doses/day): [540 \div 3 = 180 \text{ mg per dose}]
Volume: [\frac{180 \cancel{\text{ mg}}}{1} \times \frac{5 \text{ mL}}{250 \cancel{\text{ mg}}} = 3.6 \text{ mL}]
How Did You Do?
- 23-25 correct — excellent, you are ready for clinical practice
- 20-22 correct — good, review the topics you missed and retry
- Below 20 — return to the relevant modules for review
Remember
Clinical competency requires 90% or higher — 23 out of 25 correct. If you are not there yet, that is what review is for. Keep practicing.