Quantitative Reasoning and Numeracy Flashcards

A pharmacy prepares a 0.9% NaCl (normal saline) solution. 0.9% means 0.9 g of NaCl per 100 mL. How many milligrams of NaCl are in a 500 mL bag?

Answer: 4500 mg

0.9 g/100 mL × 500 mL = 4.5 g = 4500 mg of NaCl.

A hospital reports a mortality rate of 8.2 per 1000 patient admissions. If the hospital had 12,500 admissions last year, how many deaths occurred?

Answer: 103 deaths

Deaths = (8.2 / 1000) × 12,500 = 8.2 × 12.5 = 102.5 ≈ 103 deaths.

A patient requires a potassium infusion. The order reads: 'Infuse 40 mEq KCl in 100 mL NS over 4 hours.' Potassium chloride is available as 2 mEq/mL. How many mL of KCl concentrate must be added to the NS bag?

Answer: 20 mL

Volume of KCl = 40 mEq ÷ 2 mEq/mL = 20 mL.

A research paper reports that a new drug reduces LDL cholesterol by a mean of 38 mg/dL (SD = 12 mg/dL). A patient's baseline LDL is 165 mg/dL. After treatment, what is the expected LDL range for approximately 95% of patients like this one?

Answer: 103–151 mg/dL (expected mean reduction 38, ± 2 SD = ± 24 mg/dL)

Expected post-treatment LDL = 165 - 38 = 127 mg/dL mean. 95% range = mean ± 2SD = 127 ± 24 = 103–151 mg/dL.

A clinical nutrition calculation shows a patient needs 1.5 g protein/kg/day. The patient weighs 70 kg. Their current enteral formula provides 60 g protein per 1000 mL. If the patient is receiving 1200 mL/day, are protein needs being met?

Answer: No — patient needs 105 g/day but receives only 72 g/day from the formula

Requirements = 1.5 g/kg × 70 kg = 105 g/day. Formula delivers: (60 g/1000 mL) × 1200 mL = 72 g/day. Deficit = 33 g/day.

A patient's INR on warfarin was 1.8 (target 2.0–3.0). The physician increases the weekly warfarin dose by 15%. The previous weekly dose was 35 mg. What is the new weekly dose?

Answer: 40.25 mg

New dose = 35 mg × 1.15 = 40.25 mg per week.