A client is receiving an IV solution of 20,000 units of heparin in 1 L of D5W at a rate of 125 mL/hr. How many units per hour is the client receiving?

A client is receiving an IV solution of 20,000 units of heparin in 1 L of D5W at a rate of 125 mL/hr. How many units per hour is the client receiving?

• A. 1,000
• B. 3,125
• C. 2,500
• D. 3,750

Answer: (C)

Focus on converting the concentration to units per milliliter and then apply the infusion rate. The solution has 20,000 units in 1,000 mL, which is 20 units per mL. At 125 mL per hour, the delivery is 125 × 20 = 2,500 units per hour. The other numbers would only occur if the rate or the concentration changed (for example, 1,000 units/hour would require about 50 mL/hour at this concentration, while 3,125 or 3,750 units/hour would need about 156.25 or 187.5 mL/hour, respectively).

Focus on converting the concentration to units per milliliter and then apply the infusion rate. The solution has 20,000 units in 1,000 mL, which is 20 units per mL. At 125 mL per hour, the delivery is 125 × 20 = 2,500 units per hour. The other numbers would only occur if the rate or the concentration changed (for example, 1,000 units/hour would require about 50 mL/hour at this concentration, while 3,125 or 3,750 units/hour would need about 156.25 or 187.5 mL/hour, respectively).