1. Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Chapter 16 IV Flow Rate Calculation

2. Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Electronic Infusion Devices Most acute care health facilities use electronic infusion devices to deliver IV fluids to clients Programmed by mL/hr

3. Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Drip Rates If electronic infusion devices not in use, IV flow rate of mL/hr must be converted to gtt per minute (min) to deliver prescribed rate Standard drip factor (SDF) –Another term for gtt/min of IV tubing being used

4. Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. IV Tubing Calibrations Macrodrip tubing calibrated at 10, 15, or 20 gtt/mL –Labeled on tubing packaging Microdrip tubing calibrated at 60 gtt/mL

5. Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. IV Flow Rates Flow rate may vary by 1 to 2 gtt/min depending on how numbers rounded in calculations Best not to round numbers until end of calculations –Especially if using calculator

6. Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Reminder Drops must be designated in whole numbers –Cannot administer tenth or hundredth of a drop

7. Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. DA Flow rate calculation involves two values: –gtt –min

8. Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Using DA Calculate IV fluids at 125 mL/hr using tubing calibrated at 10 gtt/mL

9. Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Step 1 Enter gtt/min to be calculated as common fraction followed by equal sign gtt min

10. Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Step 2 Begin ratio entries as if calculating only gtt numerator gtt 10 gtt min 1 mL

11. Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Step 3 Match mL denominator with 125 mL/hr prescribed –One hour becomes denominator gtt 10 gtt 125 mL min 1 mL 1 hr

12. Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Step 4 Enter a 1-hr-equals-60-min conversion ratio gtt 10 gtt 125 mL 1 hr min 1 mL 1 hr 60 min

13. Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Step 5 Cancel mL and hr denominators and numerators 10 gtt 125 20.8 21 gtt/min 60

14. Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Using DA

15. Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Formula Method Used for small volumes to infuse in less than 60 min

16. Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Using Formula Calculate IV prescribed at 125 mL/hr with set calibrated at 10 gtt/mL

17. Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Formula and Division Factor Division factor determined by dividing 60 by calibration or SDF of IV set

18. Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Division Factor For calibration set of: –10 gtt/mL = 6 –15 gtt/mL = 4 –20 gtt/mL = 3 –60 gtt/mL = 1

19. Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Using Division Factor Calculate IV at 100 mL/hr using set calibrated at 10 gtt/mL Determine division factor Calculate flow rate

20. Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Microdrip When 60 gtt/mL microdrip set used, flow rate in gtt/min identical to volume in mL/hr to be infused

21. Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Regulating Flow Rate Rate can be established by dividing gtt/min by 4 and counting number of drops occurring in 15 seconds –Referred to as 15-second drip count IV drip rate of 100 gtt/min calculated as:

22. Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Correcting Off-Schedule IV Rates If rate must be increased to compensate for running behind schedule, must assess: –Type of fluid being infused –Individual’s ability to tolerate increased rate

23. Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Correcting Off-Schedule IV Rates Most clinical facilities have written protocols Recalculate flow rate using both remaining: –Volume –Time

24. Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Correcting Off-Schedule IV Rates Cannot be used for certain medications and IV fluids –e.g., heparin, insulin, and cardiogenic drugs or total parenteral nutrition Whether increasing or decreasing rate to get IV back on schedule, must closely monitor for effects of rate change