Transcript IV FLOW RATES

IV FLOW RATES
INTRODUCTION
• The pharmacy staff is responsible for
calculating the flow rate of a
medication to be administered
intravenously.
• This rate is expressed in terms of how
many milliliters per hour or drops per
minute a patient should receive.
• It can also be expressed in terms of
how much IV fluid should be prepared
per shift or per day.
• Often referred to as the infusion rate
or rate of infusion.
DURATION OF THERAPY
• The duration of therapy may be calculated using the
following formula:
Duration of therapy =
Volume of fluid or amount of drug to be infused
Flow rate
*Flow rate = ml/hr
*When calculating the duration of therapy,
always round your answer down to the whole
hour.
EXAMPLE PROBLEM
DURATION OF THERAPY
A 1 L IV is running at 125
mL/hour. How often will you
send up a new bag?
X hours = 1000 mL
125 mL/hour
= 8 hours
ANOTHER EXAMPLE PROBLEM
DURATION OF THERAPY
If an IV is running at 150 mL/hour and three 1 L
bags are sent to the floor, how long will these
bags last?
X hours = the time the 3 bags will last
X hours = 3000 mL
150 mL/hour
= 20 hours
FLOW RATE
When an order specifies a volume or amount of
drug to be given over a specific period of time,
the flow rate (mL/hr) can be calculated using the
following formula:
Flow rate =
Volume of fluid or amount of drug to be infused
Duration of therapy
EXAMPLE PROBLEM #1
FLOW RATE
The following order is sent to the IV room:
Medication: Solu-Cortef 300 mg
Fluid volume: 300 mL
Time of infusion: 4 hours
What volume of fluid is given per hour,
and what amount of drug is given per
hour?
TO SOLVE PROBLEM…….
FIRST: Determine the volume of fluid given per hour.
300 mL / 4 hours = 75 mL/hour
SECOND: Calculate the amount of drug given per hour.
300 mg / 4 hours = 75 mg/hour
EXAMPLE PROBLEM #2
FLOW RATE
The following order is sent to the IV room.
Medication: Cefazolin 500 mg
Fluid volume: 50 mL
Time of infusion: ½ hour
What volume of fluid is given per hour,
and what amount of drug is given per
hour?
TO SOLVE PROBLEM…….
FIRST: Determine the volume of fluid given per hour.
50 mL / 0.5 hours = 100 mL/hour
SECOND: Calculate the amount of drug given per hour.
500 mg / 0.5 hours = 1000 mg/hour
EXAMPLE PROBLEM #3
FLOW RATE
A 500ml IV bag is administered over 4 hours.
What is the flow rate?
TO SOLVE:
mL/hr = 500mL/4hr
X = 500/4 = 125
X = 125mL/hr
EXAMPLE PROBLEM #4
FLOW RATE
Run KCL 10MEQ in D5W 1000 ml at 80 mL/hour.
How many mL/min would this run?
FIRST: determine what is pertinent information to
solve the problem
TO SOLVE:
mL/1 min = 80 mL/60 min
X = 80/60
X = 1.33 mL/min
DROP SETS
• Pharmacy staff and the nursing staff are
responsible for calculating the rate of
administration for IV fluids in a drops per
minute rate (expressed gtt/min).
• The abbreviation gtt comes from the Latin
word guttae, which means “drops.”
• An IV set is identified by the number of drops
it takes to make 1 mL. This calibration is
referred to as a drop set or drip set.
DROP SETS
• IV sets are designed to administer medication at different rates.
• The most common sets are:
• 10, or 10 gtt/mL
• 15, or 15 gtt/mL
• 20, or 20 gtt/mL
• 60, or 60 gtt/mL
(AKA mini drip set)
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DROP SETS
• The drop sizes for the 10,15,
and 20 calibrations produce
macrodrops.
• The 60 calibration produces
microdrops.
• The 60 gtt/mL is called a
mini-drip set.
INFUSION RATES
The infusion rate, measured in drops per minute,
is calculated as follows :
x gtt/min =
Flow Rate x Drop size
60min/1hr
Flow Rate = ml/hr
Drop size = gtt/ml
(Round down to a whole drop when
a drop per minute calculation
results in a partial drop)
EXAMPLE PROBLEM #1
INFUSION RATE
If an IV is running at 60 mL/hr, what is the rate
in drops per minute using a 15 drop set?
x gtt/min = (60 mL/1 hour) x (15 gtt/mL)
60 min/hour
= 15 gtt/min
EXAMPLE PROBLEM #2
INFUSION RATE
You have D5W infusing at 80ml/hr.
What is the infusion rate in gtt/min if there are 30gtts/ml?
x gtt/min = (80 mL/1 hour) x (30 gtt/mL) = 40 gtt/min
60 min/hour