Info: Abbreviations in Health Care - cc, ml, mL and µg, ug, mcg

This information may someday help to prevent harm to you or someone you care about....

I am not a medical professional, but I thought it would be useful for people to know about a study reported in September 2007 on medication errors caused by misinterpreted abbreviations ("The Impact of Abbreviations on Patient Safety," link below).

The study examined over 640,000 medication errors, of which almost 30,000 were attributable to abbreviations, including cc (cubic centimeters) and µg (micrograms).

In the fields of medicine, nursing, and pharmacy--

cc can be mistaken for U (units) when poorly written
µg can be mistaken for mg (milligrams) when poorly written

Therefore, in health care, the written abbreviations cc and µg are strongly discouraged, and are being considered for inclusion in an official "Do Not Use" list. In some health care facilities, these abbreviations are already forbidden. To reduce errors, the recommended usage is:

Instead of cc, write ml or mL (milliliters)
Instead of µg or ug, write mcg (micrograms)

An actual case from the study--

CASE 2
A hydromorphone epidural was prescribed for a patient and written as “2 µg/mL.” The pharmacist incorrectly entered the order as “500 mg in 250 mL” and prepared and labeled the medication as “2 mg/mL.” The error was perpetuated when the nurse incorrectly interpreted the labeled medication and administered a 1,000-fold dose variance. The patient developed marked respiratory depression requiring intubation and mechanical ventilation...

Since µg is the official abbreviation for the microgram in the SI system of units, it is good to be aware that the recommended usage in health care is quite the opposite.

As mentioned, I am not a medical professional, so it would be useful to hear observations from anyone who has experience or knowledge about this issue.

References:

The Joint Commission Journal on Quality and Patient Safety
"The Impact of Abbreviations on Patient Safety" (September 2007)
http://psnet.ahrq.gov/public/Brunetti_JCJQPS_2007.pdf

Joint Commission Official "Do Not Use" List
(including list of additional abbreviations for possible future inclusion)
http://www.jointcommission.org/NR/rd...6_dnu_list.pdf

Examples showing cc and µg as unacceptable abbreviations--

Munroe Regional Medical Center (Ocala, FL):
http://www.munroeregional.com/body.cfm?id=43

Riverside Regional Medical Center (Newport News, VA):
https://www.riversidemd.net/news/200...rmacy_news.pdf

Mercy & Unity Hospitals (Minneapolis, MN):
Student & Instructor Orientation: Slides 5 and 6 - Unacceptable Abbreviations
"Orders written for an unacceptable abbreviation/practice will not be accepted or executed." / "Correct Practice: Use 'mcg'"
http://www.mercyunity.com/ahs/mercyu...ion_Part_2.pps

Thank you so much for this information - it has just answered a question for me!

Originally Posted by Barb

Thank you so much for this information - it has just answered a question for me!

You are most welcome, and I'm glad that the information was helpful.

I should also clarify the abbreviation "SI" that I myself used. The SI system of units is the international standard system of terminology for measurement throughout much of physical science, and includes units such as the meter, kilogram, and second.

SI stands for the French "Système International," or in English, the "International System" of units.

[Mrs X]

Originally Posted by Roy Nakatsuka

An actual case from the study--[INDENT]CASE 2
A hydromorphone epidural was prescribed for a patient and written as “2 µg/mL.” The pharmacist incorrectly entered the order as “500 mg in 250 mL” and prepared and labeled the medication as “2 mg/mL.” The error was perpetuated when the nurse incorrectly interpreted the labeled medication and administered a 1,000-fold dose variance. The patient developed marked respiratory depression requiring intubation and mechanical ventilation...

Hi, I think the nurse would have to be very experienced in this field to pick up that this was a 1000fold error. Their job is to administer the amount of medicine indicated on the chart. However, the pharmacist should certainly have known what concentration this was normally made up at. 500µg in 250mL compared to 500mg in 250mL should have raised warning signals.

What happened to the staff involved?

The article doesn't say what happened to the personnel in that case, but the overall source of abbreviation errors was reported as follows:

Abbreviation errors originated more often from medical staff (78.5%) in comparison to nursing (15.1%), pharmacy (4.2%), other health care providers (1.3%), and non–health care providers (0.9%).

The total magnitude of the problem is certainly alarming--over 200,000 reported medication errors per year, of which almost 10,000 each year were caused by abbreviations alone. That's just the reported errors--who knows how many went unreported.

And another finding that should make you pay close attention to prescription medications:

A study performed by Bates et al. revealed that approximately 30% of all handwritten prescriptions required clarification and correction by a pharmacist to prevent an error. Pharmacy and nursing are often charged with contacting the prescriber when abbreviations confound orders. This often causes conflict between the health care professions, further deteriorating communication.

As with most things in life, the more you know, the better you'll be able to protect your own welfare and the welfare of others.

Thread Update

Sadly, less than one month after my original post, a high-profile case involving a 1,000-fold overdose occurred on November 18 at the highly regarded Cedars-Sinai Medical Center in Los Angeles. Although the incident was not specifically caused by an error in abbreviations, it underscores the importance of understanding and verifying medical labels and dosages--

Dennis Quaid's Newborns Given Accidental Overdose
http://abcnews.go.com/GMA/OnCall/story?id=3896544

To prove how tricky this can be, if you read the news article above, did you notice the miswording in the description of the incident? No? Then look again in the fifth paragraph of the story.*

IMHO, it's also worthwhile to look at the comments posted with the story, to see how nurses, patients, and the general public are reacting--
http://abcnews.go.com/GMA/OnCall/com...ory&id=3896544


*In the fifth paragraph, the article says, "Instead of 10 units per millimeter ..." The wording should be, "Instead of 10 units per milliliter ..."

[Robert Fogt]

I read the article but saw no mistake. Without you pointing it out I would have missed it.

I was checking for errors in math, but missed the errors the unit names.

While working in the hospital I had an order for magnesium to be given. The order was written with an abbreviation of mg. I gave morphine instead. Since then, The Joint Commission now requires a physician to write out Magnesium and Morphine Sulfate. Physicians should be required to enter all orders via a computer. Many errors have been created by written orders.

what is the difference between mcg and ug?

what is the difference between mcg and ug? Which is more of one of each?