Med Math: Drop Factors Question #11


The IV mentioned above (1000 mL at 125 mL/hr) should now have 250 mL left in the bag after 6 hours but there is 350 mL so the IV is behind. What rate should the IV be set to catch up for the remaining 2 hrs?


  1. 175 mL/hr
    • Rationale:
  2. maintain the 125 mL/hr rate
    • Rationale:
  3. 150 mL/hr
    • Rationale:
  4. 75 mL/hr
    • Rationale:



Normal Saline is to be infused. You would need to know how much volume in ml you need per hour in order to solve. The total volume is set at 1000 ml to be infused. The hour is not converted to minutes to solve the problem. The 1000 ml to be infused is divided by 8 hours but now the nurse has used 6 hours up leaving 4 hours and 350 ml left. The 250 ml left is extra information and not needed to solve the problem. There is a simple formula below for calculating the flow rate.The final answer should have ml within.

Total hours substrate current hours= ____ hours left

Total hours__8hr__ – current hours__6hr__= __4hr__left

ML left


Hr left = Total ml/hr needed to catch up

350 mL/2 hr = x/ 1hr = 175 mL/hr

Learning Outcomes

Test Taking Tip

Video Rationale