The physician ordered 1 g of aminophylline in 1000 mL of D5W. It is to infuse at 12 mcg/kg/minute per infusion pump. The patient/client weighs 110 lb. What is the correct IV rate in milliliters per hour? Round to the nearest whole number.
A) 35
B) 36
C) 37
D) 38

Question

Quizplus · Accepted Answer

When solving any problem, first check that the order and the supply are in the same weight measure. For this problem, an equivalent is necessary. This is a multi-step problem. First, convert 110 lb to kilograms (1 kg = 2.2 lb): 110 lb/2.2 = 50 kg. Then determine how many micrograms per minute to infuse based on the patient/client's weight. Multiply: 50 kg * 12 mcg/kg/minute = 600 mcg/minute. Next, reduce the numbers in the standard solution to milligrams per milliliter: 1000 mg/1000 mL = 1 mg/1 mL. Then change milligrams to micrograms: 1 mg = 1000 mcg (1 mg = 1000 mcg). Divide by 60 to get micrograms per minute: 1000 mcg/60 minutes = 16.66 mcg/minute. Estimate the amount to give. Round to the nearest whole number. Formula Method: 600 mcg/minute ÷ 16.66 mcg/minute * 1 mL = 36.01 mL/hour = 36 mL/hour. Proportion (Ratios): 1 mL : 16.66 mcg :: x mL : 600 mcg; 16.66 mcg x = 600 mcg/16.66 mcg = 36 mL. Proportion (Fractions): 1 mL/16.66 mcg = x mL/600 mcg; 16.66 mcg x = 600 mcg/16.66 mcg = 36 mL. Be careful when using dimensional analysis. You need four conversion factors: 1 kg = 2.2 lb; 60 minutes = 1 hour; 1 g = 1000 mg; and 1 mg = 1000 mcg. Dimensional Analysis: 1000 mL/1 g *12 mcg/kg/hour * 1 g/1000 mg * 1 mg/1000 mcg * 60 minutes/1 hour * 110 lb * 1 kg/2.2 lb = 1000 mL * 12 * 1 * 1 * 60 * 110 * 1/1 *1000 * 1000 *1* 2.2 = 79,200,000/2,200,000 = 36 mL/hour.

The Physician Ordered 1 G of Aminophylline in 1000 ML