A client is receiving heparin IV at a rate of 1,800 units/hour. The IV solution is labeled, Heparin Sodium 20,000 Units in 5% Dextrose Injection 500 mL. After receiving the PTT result, the healthcare provider prescribes an increase of 5 mL/hour in the IV rate. The nurse should set the infusion pump to deliver how many mL/hour? (Enter numeric value only.)

Calculation: Available concentration of the heparin solution. Available concentration = Total units / Total volume = 20,000 units / 500 mL = 40 units/mL. Calculate the initial infusion rate in milliliters per hour (mL/hr). Initial infusion rate (mL/hr) = Ordered rate (units/hr) / Available concentration (units/mL) = 1,800 units/hr / 40 units/mL = 45 mL/hr. Calculate the new infusion rate after the prescribed increase. New infusion rate (mL/hr) = Initial infusion rate (mL/hr) + Increase (mL/hr) = 45 mL/hr + 5 mL/hr = 50 mL/hr.