Friday, August 29, 2014

Oops, too much morphine

A resident noticed a human factors problem that led to an accidental overdose of morphine to a patient.  It wasn't fatal, but it led to some concern, and as he notes could be more problematic in other cases.  A good catch for sure by an alert young professional!

The problem is with this drug choice given on the Epic electronic ordering system at his hospital:


What the problem?  He explains.

It is understandable that the nurse gave 20mg of morphine to the patient, since the first number in big blue letters after the word morphine is "20". The actual dose, 10mg, comes after "20MG/ML concentrated oral solution". On a busy shift, while looking up and bringing to the patient 3 or 4 other medications that shift, it would be easy to misread the morphine dose. In fact, several times our team misquoted his dose as 20mg when we discussed the dose with the nurses and the patient.

The standard dose is 10-30mg by mouth every 3-4 hours as needed for pain, so a 20mg dose is unlikely to be harmful to an adult patients. However, there are two potentially serious problems that come to mind.


First, it certainly could be dangerous for a pediatric patient, since the recommended dose in this population is 0.15 to 0.3 mg/kg. A 20kg child could receive 3.3 times the recommended dose if they were to receive 20mg instead of 6mg, which could lead to respiratory arrest.  (I'm not sure if our hospital has a weight-based dosing similar to the system at pediatric hospitals ).


The second thing that is concerning is that the FDA mandated changing the labeling of the drug from 20mg/ml to 100mg/5ml, and required that a bold warning be placed on each bottle stating "ONLY FOR USE IN PATIENTS WHO ARE OPIOID TOLERANT", since several deaths have occurred from misunderstandings of the concentration (for example, assuming the dose of 20mg meant 20ml). It is possible that the concentration used by the pharmacy is different from what is labeled on Epic, or that the nurses see a different label than I do, but if not, this could be a setup for a severe overdose.


On the "favorites list," 20mg/ml is the only liquid form available on Epic at our hospital. I will double check tomorrow if any other concentrations are available in the full formulary and let you know. The other generic forms, according to UpToDate, are 2mg/ml and 4mg/ml. Most patients use pills instead, but since our patient had problems swallowing pills we had to use the liquid.

Next day: 

I checked on the morphine ordering and it turns out they do have the 10mg/5ml dose cups available here. I think this is what the patient received, since he said "she gave me two cups instead of one" after the dosing error. It seems like although we placed the order for concentrated solution, the nurse is allowed to administer the medication in another form if she wishes.

Strangely enough though, the 10mg/5ml form does not appear on the favorites list at our hospital. The only form that is there is the 20mg/ml form. This is probably why that was the form that the
resident ordered. To get the 10mg/5ml form you have to go to the full formulary list. The favorites list changes depending on where in the hospital the patient is (for example, only the morphine PCA and injections come up on the favorites list when the patient is in the pre-op area, whereas the 20mg/ml concentrated oral solution, tablets and injections appear on the list when they are on the floor).

5 comments:

Neville Sarkari MD, FACP said...

The 20mg/ml (or 100mg/5ml) is preferred in hospice care. However, some hospitals restrict this concentration to oncology floors etc.

Definitely need to state the concentration and the actual dose very carefully in the orders.

Peter Yang said...

In the patient safety committee at my old hospital, we identified that medications orders which contain concentration, dose, +/- volume are at high risk for prescriber/patient errors. I believe that part of the errors can be attributed to a lack of effective standards in medicine for consistently communicating information about medication. Most prescribers probably think in terms of dosage, such as mg, whereas patients may focus on another unit, such as mL or # of pills. Although undoubtedly important, the concentration of a medication is probably the least important part of the prescription to the patient, coming behind: drug name, route, amount of (unit) to be taken, and frequency. A point of emphasis on the most component of the prescription by using something as simple as bolding could draw emphasis where it is needed.

Unfortunately, even pill orders can cause confusion, such as: warfarin 5 mg take 0.5 pill daily every Monday, Wednesday, Friday. Some patients may be confused about whether they're using 5 mg or will be receiving a 5 mg dose as the result of cutting a 10 mg pill in half. Some may misread it as truly being used every day rather than just MWF.

At HemOnc.org, we have thought about how we can more consistently communicate about high-risk medications like chemotherapy, particularly since journals are rather inconsistent with how they report this information (and omit some as well). To this end, we included a section about this in our style guide. This has worked well for us, although I think iterative adjustment/improvements will be needed as additional cases arise.

nonlocal MD said...

Aggh, yet another issue just crying out for standardization. How long will it take?

Ryan E. said...

Odd to me that the expanded MAR view the RN would see isn't displayed? Epic is product specific. EMRs don't negate the fact people need to be aware of patient safety. I have an image of what the MAR would looke like I am happy to send to you. Clearly states 0.5 ml is the dose. Also why was BCMA not used? All these discriptions come from drug databases like FDB. People become too reliant on machines and forget that nurses, physicians, pharmacists, etc are well payed because they have education AND responsibility

Anonymous said...

My daughter was accidently overdosed and died on morphine while on hospice. The bottle stated .6 to 1.2 mg it was translated at home as .6ml the concentration was 100/5ml. Not a day goes by I don't feel guilty. She was dying and was going to go within the next 24/48 hours. But my giving her the medicine did her in.