This document discusses basic intravenous therapy calculations. It outlines the learning objectives which include calculating IV flow rates, interpreting IV labels, and setting up PCA pumps. The document introduces different types of IV lines like peripheral and central lines. It describes how to calculate IV flow rates in two steps: 1) calculating mL/hr when the total volume is given, and 2) calculating drops/min when the mL/hr rate is given. The document provides examples and emphasizes the importance of accurate calculations to ensure safe IV administration.

1. BASIC INTRAVENOUS
THERAPY CALCULATIONS
By ROMMEL LUIS C. ISRAEL III

2. LEARNING OBJECTIVES
At the end of the lecture, the students will be able to:
• Analyze IV orders for safe administration using critical thinking
skills.
• Analyze medication errors using critical thinking skills.
• Identify osmolarity values for IV solutions
• Identify various electronic IV infusion devices.
• Identify IV sets: primary, primary with a port, IVPB extension tubing,
transfusion sets, and venous access devices for intermittent use.

3. LEARNING OBJECTIVES
• Calculate intravenous (IV) flow rates for drops per min, mL per hr,
mg per g per hr, and infusion time.
• Interpret IV labels.
• Calculate the amount of saline or heparin for use in keeping
venous access patent.
• Calculate the grams of sodium chloride or dextrose in IV bags.
• Check physician’s IV order for type of solution, amount, additives,
and rate.
• Set PCA pump using standard protocol.

4. INTRODUCTION
It is the nurse’s responsibility to calculate the milliliters per
hour or drops per minute to regulate an intravenous infusion.
Knowledge of electronic infusion devices is required as is
knowledge of the basic hand-regulated primary sets.
The nurse is responsible for calculating the intravenous
piggyback (IVPB) infusions that are timed for shorter periods.

5. IV INFUSIONS
• They are used more frequently today than
intramuscular (IM) injections.
• Continuous medication therapy can be delivered
via an IV routeminimizing multiple injections via
the IM route.

6. IV INFUSIONS
• Intermittent medication therapy can be delivered through a
saline/heparin lock, which allows the patient free movement until
the next scheduled dose.
Intermittent lock covered with a rubber diaphragm. (From Perry AG, Potter PA: Clinical nursing skills
and techniques, ed 7, St Louis, 2010, Mosby.)

7. IV INFUSIONS
• The saline lock is used for intermittent short-duration therapy in
acute care, long-term care, and home care.
• Intermittent therapy can also be delivered as a piggyback with a
continuous infusion.
• A heparin flush can also be used to keep the port patent.

8. IV INFUSIONS
• Medications (additives) can be added to the IV by
the manufacturer, pharmacist, or nurse.
• The physician orders the medication, strength,
and amount, as well as the type and amount of
diluent.
• It is important that the person responsible for the
IV understand the actions of the medication, flow
rate, adverse reactions, and antidotes.

9. IV INFUSIONS
• IV fluids flow directly into the vein, resulting in
immediate action, and cannot be retrieved.
• Therefore, it is imperative that the correct
calculations, medications, and flow rate be
administered.

10. IV INFUSIONS
Other terms for intermittent IV lock:
• Saline lock
• Hep lock
• PRN cap
• Intermittent IV (INT)
• Intermittent peripheral infusion device (IPD).

11. IV INFUSIONS
All intermittent IV lock have needleless resealable:
Needleless infusion system Connection into an injection port
(From Perry AG, Potter PA: Clinical nursing skills and techniques, ed 7, St Louis, 2010, Mosby.)

12. TYPES OF IV LINES
1. Peripheral Line
• It is usually used for fluid replacement and temporary intermittent
medication administration.
• It is inserted in the hand, arm, or possibly leg if the hand or arm
cannot be accessed.
• Foot and scalp sites are used for infants.

13. TYPES OF IV LINES
2. Peripheral inserted central catheter
(PICC)
• It is longer than a central catheter line (approximately 22 inches in
length).
• The insertion point is usually the vein in the antecubital region of the
arm, where the line is then advanced into the superior vena cava.
• It is inserted by a PICC-certified RN or physician.
• Only solutions with a osmolarity of less than 10% should be administered
via peripheral lines.

14. TYPES OF IV LINES
2. Peripheral inserted central catheter
(PICC)
Peripheral inserted central catheter (PICC lines). The
double-lumen catheter is used to draw blood samples.

15. TYPES OF IV LINES
3. Central line
• A central line is inserted by an MD
directly into the jugular or subclavian
vein and then into the superior vena cava.
• This type of line is for therapy requiring a
longer period of time.
Central line with a medi-port.
(From Perry AG, Potter PA: Clinical nursing skills and techniques, ed 7, St
Louis, 2010, Mosby.)

16. INTERMITTENT FLUSHING RANGES
Catheter Flush Solution Volume (mL)
Peripheral Normal saline 1-3 mL
Peripherally inserted central
catheter (PICC) Normal saline
3-5 mL
Central venous Heparinized saline
5-10 mL of saline followed with 3 mL
heparin 1:100 units per mL
When flushing peripheral IV lines, a 10 mL syringe should be used. A
smaller syringe creates greater pressure within the line, which may
cause damage to the vein and be harmful to the patient.

17. IV CALCULATIONS
• Check IV orders before beginning calculations.
Two steps in IV calculations:
1. Find out how many milliliters per hour (volume) the IV is
ordered to infuse.
2. Calculate the drops per minute needed to infuse the ordered
volume.

18. IV CALCULATIONS
ANALYZE YOUR PROBLEM
• If the order says to infuse the IV for 24 hours, calculate the mL per
hr by beginning with Step 1
• If the order says to infuse the IV at 75 mL per hr, begin with Step 2

19. If the order says to infuse the IV for 24 hours,
calculate the mL per hr by beginning with Step 1
RULE:
- When the total volume is given, calculate the mL/hr.

20. If the order says to infuse the IV for 24 hours,
calculate the mL per hr by beginning with Step 1
Example:
Ordered: 2000 mL D5W to be infused for 24 hours. The
problem is to find out how many mL per hr the patient must
receive for the 2000 mL to be infused in 24 hours.
•
We now know that to infuse 2000 mL of fluid in 24 hours, the patient must
receive 83 mL per hr. Infusion devices are calibrated for mL per hr.

21. If the order says to infuse the IV at 75 mL per
hr, begin with Step 2
DROP FACTOR CALCULATIONS
step 2
Drops per min
• The drop factor is needed to calculate drops per min.
• The drop factor is the number of drops in 1 mL.

22. If the order says to infuse the IV at 75 mL per
hr, begin with Step 2
• The diameter of the needle where the drop enters the drip
chamber varies from one manufacturer to another. The bigger the
needle, the fatter the; it takes only 10 macro drops to make a
milliliter.
• The smallest unit is the microdrop (60 drops per mL). This is used
for people who can tolerate only small amounts of fluid, such as
pediatric and geriatric patients and patients who require fluid
restrictions. Drop factors of 10, 15, 20, and 60 (microdrip) are the
most common. The drop factor is determined by the manufacturer
and is found on the IV tubing package.

23. IV BAG A
InterLink® System Continu-Flo®
Solution Set with drop factor of
10 (10 drops = 1 mL)
IV BAG B
InterLink® System Continu-Flo®
Solution Set with drop factor of
60 (60 drops = 1 mL).
Drops per minute must be calibrated for
gravity flow

24. If the order says to infuse the IV at 75 mL per
hr, begin with Step 2
RULE:
- When the mL per hr is given, calculate the drops per min.

25. If the order says to infuse the IV at 75 mL per
hr, begin with Step 2
Example:
Ordered: D5W to infuse at 83 mL per hr. The drop factor (Df)
is 10.
Drops cannot be timed in tenths, only in whole numbers. If
the decimal is greater than or equal to 0.5, round to the next
higher number.

26. If the order says to infuse the IV at 75 mL per
hr, begin with Step 2
• Example:
Ordered: Antibiotic to infuse at 100 mL in 30 min. The drop
factor is 15.

27. SUMMARY
Two-step IV flow rate calculations

28. REMEMBER THIS
• Reduce the fraction Df per min before multiplying by the volume.
Example:
Which would you rather calculate?
The reduced fraction is easier to calculate.

29. REMEMBER THIS
• When the IV tubing is microdrip (60 drops per Ml), the drops per
min will be the same as the mL per hr.
Example:
1000 mL to infuse in 8 hours with a micro drip set.

30. DROP PER MINUTE BY MANUFACTURER
Manufacturers have established rates for their products. Below is an
example.

31. DROP PER MINUTE BY MANUFACTURER
Product Drip Rates Minutes Df = Reduced Number
60 drops per mL 60 60 = 1
20 drops per mL 60 20 = 3
15 drops per mL 60 15 = 4
10 drops per mL 60 10 = 6
You may have to memorize only one
number because most facilities purchase
equipment from a single company.

32. Example:
- If you know you are using a set that delivers 20 drops per
mL, divide 3 into the mL per hr.
- As you already know, the formula for calculating drops per min is:
•
Now you know two different methods for calculating drops per min.

33. CLINICAL ALERT
• Check the IV every hour, even if an infusion device is used.
• Recheck drops per minute rate frequently because the IV rate can
vary with position.
• Time taping the IV has become important as electrical blackouts
and brown outs can adversely affect the device.

34. Superficial Veins of Upper Limb
- Basilic & Cephalic veins
From:
Dosage Calculations for Nursing Students on IV Drip Rate Factors Made Easy (Video 4. “Dosage Calculations for Nursing Students on IV
Drip Rate Factors Made Easy (Video 4).” YouTube, 28 Sept. 2015, youtu.be/W5VIc6f0fBA. Accessed 8 Apr. 2020.
Click the picture to
watch the video
Copy-paste
the link
below to
watch the
video online

35. Source:
Themes, U.F.O. (2016). Basic Intravenous Therapy Calculations.
[online] Basicmedical Key. Available at:
https://basicmedicalkey.com/basic-intravenous-therapy-
calculations/ [Accessed 18 Feb. 2022].
Dosage Calculations for Nursing Students on IV Drip Rate Factors
Made Easy (Video 4. “Dosage Calculations for Nursing Students on IV
Drip Rate Factors Made Easy (Video 4).” YouTube, 28 Sept. 2015,
youtu.be/W5VIc6f0fBA . Accessed 8 Apr. 2020.