Process
10th Edition
• Author(s)Linda Lane Lilley;
Shelly Rainforth Collins; Julie
S. Snyder
TEST BANK
,Question 1: Medication Calculation
• Clinical Scenario: A 4-year-old pediatric patient weighing
35.2 lbs is admitted with acute otitis media. The healthcare
provider prescribes amoxicillin oral suspension $90\text{
mg/kg/day}$ divided into two equal doses every 12 hours.
The pharmacy dispenses amoxicillin oral suspension
reconstituted to a concentration of $400\text{ mg/5 mL}$.
• Question Stem: How many milliliters (mL) should the nurse
administer per dose? (Round the final answer to the
nearest tenth.)
• Answer Options: * A) 4.0 mL
o B) 4.5 mL
o C) 9.0 mL
o D) 18.0 mL
• Correct Answer: B) 4.5 mL
• Comprehensive Rationale: * First, convert the patient's
weight from pounds to kilograms:
$$\text{Weight in kg} = \frac{35.2\text{ lbs}}{2.2\text{ lbs/kg}} =
16\text{ kg}$$
o Next, calculate the total daily dose required:
$$\text{Total Daily Dose} = 16\text{ kg} \times 90\text{
mg/kg/day} = 1,440\text{ mg/day}$$
, o Divide the total daily dose by 2 to determine the dose
per administration (every 12 hours):
$$\text{Dose per administration} = \frac{1,440\text{ mg}}{2} =
720\text{ mg/dose}$$
o Finally, use the dimensional analysis or
ratio/proportion method to find the volume in mL per
dose based on the available concentration ($400\text{
mg/5 mL}$):
$$\text{Volume per dose} = \frac{720\text{ mg}}{400\text{ mg}}
\times 5\text{ mL} = 1.8 \times 5\text{ mL} = 9.0\text{ mL per
dose? No, let's re-multiply: } 1.8 \times 5 = 9.0\text{ mL? Wait.
Let's recalculate: } = 1.8. 1.8 \times 5 = 9.0\text{
mL.}$$
Wait, let's re-verify the math: $16 \times 90 = 1440\text{
mg/day}$. Divided by 2 = $720\text{ mg/dose}$. Concentration
is $400\text{ mg / 5 mL}$.
$$\frac{720\text{ mg}}{400\text{ mg}} \times 5\text{ mL} =
9\text{ mL}.$$
Let me correct the option and the math so it perfectly matches.
If the answer is 9.0 mL, let's ensure the options represent this
correctly. Let's choose C as the correct answer and adjust the
rationale.Correction:
, $$\text{Volume per dose} = \frac{720\text{ mg}}{400\text{ mg}}
\times 5\text{ mL} = 9.0\text{ mL}$$
• Correct Answer Updated: C) 9.0 mL
• Distractor Analysis:
o A) 4.0 mL: Incorrect. This calculation error results
from failing to multiply by the 5 mL volume unit or
incorrectly using a $250\text{ mg/5 mL}$
concentration equivalence. Medication safety risk
includes subtherapeutic dosing.
o B) 4.5 mL: Incorrect. This value represents a single
dose if the total daily dose was accidentally divided by
4 instead of 2, or if the weight conversion was
performed incorrectly. Risk is severe underdosing,
risking treatment failure of the bacterial infection.
o D) 18.0 mL: Incorrect. This represents the total daily
volume ($1,440\text{ mg}$) administered as a single
dose instead of divided into two doses. Medication
safety risk includes severe toxicity, GI distress, and
toxic serum levels.
• Nursing Process Integration: Implementation. The nurse
must accurately calculate and measure the exact volume of
medication to ensure safe administration. Assessment of
weight is a prerequisite step.