Final answer:
To calculate the infusion rate per hour for Ringer's Lactate ordered at 1000 ml over 12 hours, divide the total volume by the total time, giving an infusion rate of 83.33 ml per hour.
Step-by-step explanation:
If a physician orders 1000 ml of Ringer's Lactate to infuse over 12 hours, the calculation to determine how many ml infuses per hour is a simple division. You divide the total volume of the IV fluid by the number of hours over which it is to be infused.
To find the rate of infusion per hour:
Total volume of Ringer's Lactate = 1000 ml
Total time for infusion = 12 hours
Rate of infusion (ml per hour) = Total volume ÷ Total time
Rate of infusion = 1000 ml ÷ 12 hours
Rate of infusion = 83.33 ml per hour
Note that when we perform this division, we end up with a repeating decimal. In practice, this might be rounded to the nearest whole number based on the accuracy of the infusion pump or the drops per minute if gravity fed. However, with precise electronic infusion pumps, the exact number could be used.
The infusion rate represents how much volume of the Ringer's Lactate solution will be delivered per hour to the patient.