Med Math: Drop Factors Question #8


The client with the IV ordered above (500 mL NS over 5 hours) went for a scan and the IV pump was removed. Two hours are left and there should be 200 mL left but there is only 150 ml so the IV is now AHEAD of schedule. What should the rate be slowed down to?


  1. maintain 100 mL/hr
    • Rationale:
  2. 75 mL/hr
    • Rationale:
  3. 200 mL/hr
    • Rationale:
  4. 55 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 500 ml to be infused for required time. The hour is not converted to minutes to solve the problem. The 500 ml is the total volume infused over the 5 hours but now the problem indicates you as the nurse now have 150 ml left not 200 ml. The 200 ml would be extra information and not needed to solve the problem. The hours left would need to be calculated next in order to solve. If 5 hours are the total and 3 hours have gone by then that leaves 2 hours left to calculate. The final answer should have ml/hr within.


—– x 1 (understood to be 1 as in 1 hour) = Total volume per hour is ml/hr



—————- = _75__ml/hr

Hr _2 __

150 mL/2 hr = x/ 1hr

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