NOMOGRAMS

Question 1

Order: Heparin Bolus at 80u/kg

Supply: 1mL Heparin Vial at 1000u/mL and 1mL heparin vial at 10,000u/mL as per protocol.

Patient weighs 110lbs and their aPTT is 29 seconds.

Heparin protocol is as follows:

1. Boluses to be given at 1000u/mL
2. Bolus with 80u/kg. Start drip at 18u/kg/hr

40kg - initial bolus at 3200u (3.2mL)
50kg - initial bolus at 4000u (4mL)
60kg - initial bolus at 4800u (4.8mL)
70kg - initial bolus at 5600u (5.6mL)
80kg - initial bolus at 6400u (6.4mL)

ACCORDING TO THIS INFORMATION how much Heparin should they receive in their bolus?

Answer 1

Because we are providing a Bolus, we do not need to worry about their current aPTT levels as we are NOT titrating. So…

Convert weight: 110lbs / 2.2 = 50kg

2 ways to answer: Look at the chart, but you SHOULD always verify with math to ensure you’re following protocol.

So… 50kg x 80u/kg = 4000u of Heparin

Then, D/SxQ

4000u / 1000u x 1mL = 4mL

So the order of 4mL of heparin is verified for this patient.

Question 2

Order: Heparin Sodium 25000u in 250mL NS

Supply: 1mL Heparin Vial at 1000u/mL and 5mL Heparin vial at 10,000u/mL

Patient weights 110lbs

Which vial should you draw from and How many mLs of the heparin vial should be loaded into the 250mL bag?

Answer 2

Draw from the 5mL vial as the 1mL will not have nearly enough solution.

Doc / Stock x Quantity

25000u / 10000 x 1mL = 2.5 mL from the 5 mL heparin vial should be loaded into the 250 mL bag.

Question 3

Order: Start Heparin Drip at 18u/kg/hr

Supply: Heparin Sodium 25000u in 250mL

Patient weighs 176 lbs

The Following is infusion protocol:

40kg - infuse at 700u/h
50kg - infuse at 900u/h
60kg - infuse at 1100u/h
70kg - infuse at 1300u/h
80kg - infuse at 1400u/h
90kg - infuse at 1600u/h

How many mL/hr does the patient receive?

Answer 3

Convert weight: 176 / 2.2 = 80kg

Initial infusion rate for 80-89kg is 1400u/h

Specifically the patient is 80kg, so…

80kg x 18u/kg/hr = 1440u/hr (which falls into the protocol parameters)

So to calculate mL/h…

1440u / 25000 x 250mL = 14.4mL/h infusion in a 250mL bag

Question 4

You obtain the results from you’re patient’s recent aPTT test and discover their aPTT is 37 seconds.

Pt. weight is 68kg and their current infusion is set at 1150u/hr from a 250mL bag with 25000u of Heparin Sodium.
Vial for bolus is 10000u/5mL

The following is a Heparin/PTT chart:

If PTT is:
less than 35 sec - Rebolus with 80u/kg and increase infusion by 4 units/kg/h
36-44 sec - Rebolus with 40u/kg and increase infusion by 3u/kg/h
45-75 sec - Continue current scale
75-90 sec - Decrease infusion rate by 2u/kg/hr
Greater than 90 seconds - Hold Infusion for 1 hour and then decrease infusion by 3u/kg/hr

According to this chart, how many mL should the patient receive in their Bolus? How many more mL/hr will their infusion be? What is the new hourly rate in mL/hr?

Answer 4

To find new Bolus order…..

chart says rebolus with 40u/kg

68kg x 40u/kg = 2720u Bolus.

2720u / 10000u x 5mL = 1.4mL injection of Heparin Sodium

So the order should read:

Change in infusion (How many more mL/hr):
Chart states to add 3u/kg/h:

68kg x 3u/kg/hr = 204u/hr (CONVERT INTO mL/hr)

204u / 25000u x 250mL = 2mL/hr added to the infusion

New mL/hr Total: Calculate mL/hr prior to adjustment:

1150u / 25000u x 250mL = 11.5mL/hr

11.5mL/hr + 2mL/hr = 13.5mL/hr is the new infusion rate.

Question 5

Your patient’s PTT is 87 sec. You notice their infusion is set to 900u/hr from a 100mL bag with 10000u of heparin. They weigh 132 lbs.

The following Heparin chart should be used:
If PTT is:
less than 35 sec - Rebolus with 80u/kg and increase infusion by 4 units/kg/h
36-44 sec - Rebolus with 40u/kg and increase infusion by 3u/kg/h
45-75 sec - Continue current scale
75-90 sec - Decrease infusion rate by 2u/kg/hr
Greater than 90 seconds - Hold Infusion for 1 hour and then decrease infusion by 3u/kg/hr

What is the new infusion rate in mL/hr?

Answer 5

Convert weight: 132 x 2.2 = 60kg

Decrease infusion by 2u/kg/hour:

2u/kg x 60kg = decrease by 120u/hr

So the easiest way to do this would be to subtract as you have the current infusion already in units…

900u/hr - 120u/hr = 780u/hr is the new infusion rate.

Convert into mL/hr…

780u / 10000u x 100mL = 7.8mL/hr is the new infusion rate in mL/hr

Question 6

Your patient’s PTT is 26 seconds. You notice their infusion is set to 1400u/hr from a 250mL bag with 20,000u of Heparin. They weigh 209 lbs.

Heparin Bolus supply is a 5mL vial with 10000u

The following Heparin chart should be used:
If PTT is:
less than 35 sec - Rebolus with 80u/kg and increase infusion by 4 units/kg/h
36-44 sec - Rebolus with 40u/kg and increase infusion by 3u/kg/h
45-75 sec - Continue current scale
75-90 sec - Decrease infusion rate by 2u/kg/hr
Greater than 90 seconds - Hold Infusion for 1 hour and then decrease infusion by 3u/kg/hr

What should you do? Specify treatment that pertain to the patient (in mL and mL/h)

Answer 6

Convert weight: 95kg

Rebolus with 80u/kg and increase infusion by 4u/kg/hr

Bolus - 80u/kg x 95kg = 7600u Bolus.

7600u / 10000u x 5mL = 3.8mL injection

Infusion: Decrease by 4u/kg/hr

4u/kg/hr x 95kg = 380u/hr

380u/hr / 20000u x 250mL = 4.75mL/hr decrease in infusion rate.