Doctor’s Digest’s ISMP Med/Hazard Tips

Invanz or IV Vanc?

A handwritten recommendation in the progress notes for “Invanz 1 g q 24h” was misread by a physician as “IV vanc (vancomycin) 1 g q 24h;” vancomycin 1 gram IV every 24 hours was subsequently prescribed. Although a 1 g dose every 24 hours may be appropriate in patients with renal insufficiency, the error was identified by a pharmacist prior to reaching the patient because the dose was too low for this patient without renal impairment. Both are antibiotics. Vancomycin is sometimes improperly referred to as “vanc” or “vanco,” increasing the risk of errors if after this incident was reported, an annual review of the hospital’s sound- and look-alike drug names list occurred at a pharmacy and therapeutics meeting. A physician raised the issue of confusion, mentioning a similar event in the past. In fact a May 15, 2002 article in the ISMP Medication Safety Alert! carried a Safety Brief about the exact same type of error, which led to a patient receiving vancomycin in error. As a result of the above error, pharmacists in this health system were notified via email of the potential for confusion. Awareness of this error, electronic medical records, computer alerts, printed antibiotic order sheets, and prohibiting the use of drug name abbreviations may be helpful in preventing this mix-up.

Confusion between Casodex and Kapidex

There have been reported instances of medication errors due to name confusion between KAPIDEX (dexlansoprazole) and CASODEX (bicalutamide). Both written and verbal prescriptions have been dispensed in error. Kapidex is indicated for healing of erosive esophagitis, maintenance of healed erosive esophagitis, and treatment of symptomatic nonerosive gastroesophageal reflux disease (GERD). It is available as 30 mg and 60 mg delayed-release capsules for oral administration. Casodex is indicated for use in combination herapy with a luteinizing hormone-releasing hormone (LHRH) analog for the treatment of stage D2 metastatic carcinoma of the prostate. Casodex is available as 50 mg tablets for oral administration.

Patients who receive either drug in error could be unnecessarily subjected to unintended effects and/or adverse events. Specifically, Casodex is contraindicated in women. To reduce the potential for medication errors, please take time to verify written or verbal orders and build an alert in your computer system. If you are a prescriber, please include the drug’s purpose on prescriptions.

Confusion between Kapidex and Capadex

In addition to an alert posted today about mix-ups between Kapidex and Casodex, we also heard from a pharmacist who received a prescription from a doctor’s office via telephone for Kapidex. The office nurse had misspelled the drug as “Capadex,” probably because she heard the doctor pronounce the drug name and then transcribed it phonetically. When the pharmacist tried to enter the medication into the computer, he could not find “Capadex.” The pharmacist asked others in the pharmacy if the prescribed drug could be Casodex. Meanwhile, one of the pharmacists searched “Capadex” using Google to see if it was an actual product. He saw many listings for “Capadex” as well as a listing for Kapidex. But “Capadex” is a foreign product containing acetaminophen and propoxyphene (similar to available in Australia and New Zealand, and online.) At least one site advertises that no prescription is needed.

We’ve notified FDA about this new issue associated with the brand name “Kapidex.” Given that the name is being confused with Casodex and could lead to dangerous confusion with the foreign product Capadex, this might be a case where a name change is appropriate.

Baclofen programming error with SynchroMed II pump - Facility not made aware of company’s software updates

A recent error while programming a Medtronic SynchroMed II implantable pump led to a significant baclofen overdose in a patient with muscle spasticity, causing persistent weakness in his lower extremities. A few months earlier, the pump had been implanted to deliver baclofen intrathecally, which achieves cerebrospinal fluid drug levels up to 30 times higher than those achieved with oral doses while maintaining low serum concentrations to minimize the drug’s side effects.(1)

On the day of the error, the patient visited his physician for a pump programming change. Because the patient’s symptoms from his disease were worse in the mornings, the physician wanted to reprogram the pump to deliver an extra bolus dose of baclofen over 1 hour each morning. A small, portable N’Vision Clinician Programmer (http://professional.medtronic.com/devices/synchromed-II-for-pain/programmers-and-accessories/index.htm) was used to reprogram the pump. The programmer is equipped with a touch screen display for data entry, a telemetry head that must be placed as close as practical to the implanted pump, and a port through which communication can be established with compatible printers. A therapy application card that contains application-specific software is supplied separately.

Various programming options exist with the SynchroMed II pump, including a “flex mode,” which allows practitioners to program a sequence of independent dosing intervals to deliver more or less drug at scheduled times each day when patients experience increased or decreased symptoms. In this case, the physician accidentally programmed the small bolus dose intended for each morning in a manner that changed the overall delivery to a 60 mcg dose every hour throughout the day, rather than 60 mcg per day.

Shortly after arriving home, the patient experienced increasing weakness and called his physician, who suspected that a programming error had occurred. The physician asked the patient to return to the office immediately. For undetermined reasons, the patient failed to return to the physician’s office but presented in the emergency department (ED) 5 hours later and was admitted to the intensive care unit. The patient was hospitalized for 13 days until strength in his legs was adequate for safe ambulation at home.

During discussion of this event at the hospital, another physician familiar with Medtronic implantable drug delivery and neurostimulation devices recalled that she had heard elsewhere that the company had made software updates to the N’Vision Clinician Programmer to help reduce the risk of errors. After an investigation, it was determined that a letter or notification about the software updates was never communicated to this provider.

Medtronic had issued a letter (currently on our Web site at: www.ismp.org/docs/medtronics.pdf) to healthcare providers in February 2009 to alert SynchroMed II and SynchroMed EL pump users to reports of under- and overdoses that resulted when programming the pumps, particularly bolus doses. The letter informed providers that modifications had been made in the software application card used with the N’Vision Clinician Programmer. For example, changes were made to: the navigation screens for priming bolus doses and bridge bolus doses (to clear old drug from the fluid pathway when changing the drug or concentration); the summary screen, which, along with the total dose, now includes the percent of the dose increase or decrease from the prior setting; and the confirmation screen, which now recaps the total dose.

In the February 2009 letter, Medtronic noted that errors while programming the pumps can lead to serious patient injury, including death, and that the company wanted to ensure that customers were always using the most current version of the programmer software. However, it is not clear whether all potential healthcare providers who use the N’Vision Clinician Programmer are aware of the possibility of errors and the software update. One day after the adverse event, a Medtronic representative updated the software on two of the hospital’s N’Vision Clinician Programmers. The following day, the hospital called the company to learn why they had not heard about the software update in February 2009. A company representative told the hospital that the letter was not mailed directly to all healthcare providers; rather, the letter was often left behind in hospitals after sales representatives visited them to update the software.

If inpatient or outpatient providers in your organization care for patients with implanted SynchroMed pumps and program these pumps, please check that the latest software updates for the N’Vision Clinician Programmer have been provided by the company. The model 8870 versions AAG and AAJ software application cards should be replaced by version AAH or newer. If you have questions, contact your Medtronic representative or call Medtronic technical services at: 1-800-707-0933.

Also, advise ED staff to be aware of implantable drug pump-related adverse events, and to ask patients when the last refill and/or programming change occurred. If this has occurred within a few days of admission, there is an increased likelihood that an error occurred. For example, patients receiving intrathecal baclofen therapy might exhibit signs of an overdose—somnolence, respiratory depression, seizures, rostral progression of hypotonia, loss of consciousness, coma—or baclofen withdrawal (from a subtherapeutic dose)—pruritis without rash, diaphoresis, hyperthermia, hypotension, sudden increase in muscle spasticity and rigidity.2

References:
1) Gaffen A, Nesic M, Coleman G. Intrathecal baclofen (Lioresal): suspected adverse incidents associated with implantable drug pump system. Canadian Adverse Reaction Newsletter. October 2005;15(4):1-2.
2) Medtronic. SynchroMed II programmable pumps implant manual (8637). 2003. Available at: http://professional.medtronic.com/downloads/itb/M221311A_a_014.pdf.

Order by metric weight, not volume

A pharmacist who manages an electronic database for a health system told us that he frequently receives requests to use mL as the ordering unit with oral liquids (versus metric weight [e.g., mg, g]). The pharmacist wanted to know if we had a position that agreed with his, which is to prescribe oral liquid medications using metric weight. In the ISMP book, Medication Errors, we noted that, in most cases, it is un-acceptable to express doses or quantities in terms of dosage form or volume alone. Volume may be used along with a strength or concentration; for example, it is acceptable to prescribe 5 mL of a solution of 100 mg/5 mL (though unnecessary if the dose in mg is prescribed). It is also acceptable to prescribe by volume when: 1) there is no strength due to a combination of many ingredients, or no active ingredient (e.g., cola syrup); 2) when the active ingredient is available only as a liquid in a single strength (e.g., paregoric); and 3) when prescribing certain external-use items such as creams, lotions, and drops (e.g., “add 10 drops to vaporizer water”).

Usually, however, prescribing by volume alone presents a hazard. For example, Fer-In-Sol (ferrous sulfate) contains 15 mg of iron per mL while generics contain 15 mg of iron per 0.6 mL (25 mg/mL). The brand product contains 40% less elemental iron per mL than generics. If Fer-In-Sol is prescribed in terms of mL and generic substitution is allowed, the patient would receive nearly twice as much iron as intended. Healthcare providers should specify the dose in mg and alert parents when multiple concentrations are available.

“UD” - ambiguous and dangerous abbreviation

A serious medication error resulted when a nurse did not know what “UD,” a medical abbreviation derived from Latin, meant. A pharmacist had added it to directions on an electronic nursing medication administration record (eMAR). The rate of infusion for an IV diltiazem solution was not yet known in the pharmacy, so the pharmacist who entered the prescription into the computer entered “UD” (ut dictum or “as directed”) from a drop-down list used to populate the rate field. The nurse, upon seeing the notation on the eMAR, thought it meant that the 125 mg infusion was a “unit dose” injection. The nurse proceeded to give the diltiazem at 125 mg/hour and infused the entire dose over 1 hour (the rate should have been 5 mg/hour). The nurse then requested and received another diltiazem drip from the pharmacy and administered the entire 125 mg infusion again over 1 hour. Pharmacy staff did not question why another bag was needed so soon. The patient later expired.

At a subsequent meeting to review the event, it was revealed that the majority of nursing staff thought “UD” meant “unit dose.” This is a great example of why pharmacists and doctors should NOT use Latin abbreviations that others may not understand. We agree with the hospital, which asked their computer system vendor to eliminate the ability to enter “UD” in the rate field. While some pharmacists and doctors are familiar with the abbreviation as learned in pharmacy school, it is as archaic as the apothecary system of measurement and should not be used because it’s too easily confused with “unit dose.”

We plan to add “UD” (for ut dictum) to our list of dangerous abbreviations posted on our website (www.ismp.org). We would also recommend that you help make other healthcare professionals in medicine, nursing, and pharmacy aware of this incident. Thank you.

Safer catheter connectors in the UK

The National Patient Safety Agency (NPSA), a patient safety oversight government agency that is part of the National Health Service in the United Kingdom (UK), has just published an alert to ensure that as of April 1, 2011, all spinal (intrathecal) bolus doses and lumbar puncture samples will be performed using syringes, needles, and other devices that will not connect with IV Luer connectors. Further, as of April 1, 2013, all epidural, spinal, and regional infusions and boluses must be delivered with devices that will not connect with IV Luer connectors or IV infusion spikes. Currently, standard medical connectors (Luer connectors) are used in a wide variety of systems including the administration of IV, spinal, and other injections. Their wide use has exposed patients to the risk of accidentally delivering spinal and epidural medicines IV, and vice versa, with fatal results.

A full range of devices with safer connectors are not yet available. However, some new products are commercially available (www.neurax.co.uk) and representative industry groups and other key stakeholders support this initiative. It is believed that this move will stimulate additional manufacturers to develop safer connectors that will not allow a Luer connection. Copies of the Patient Safety Alert (being issued in two parts because there are two implementation dates), together with supporting information, are on the National Reporting and Learning Service (NRLS) website at: www.nrls.npsa.nhs.uk/resources/type/alerts/?entryid45=65259.

Lithium safety alert

In recognition of patient harm that sometimes occurs in patients taking lithium, the National Patient Safety Agency (NPSA) in England and Wales has released an alert on safer lithium therapy. The alert, sent to all healthcare organizations where lithium therapy is initiated, prescribed, dispensed, and monitored, requests compliance with safe treatment practices established by the National Health Service. These include informing patients of the known side effects or symptoms of lithium toxicity and scheduling regular blood tests, which are important as a basis for dose adjustments when appropriate. Clinically significant alterations in lithium blood levels may occur with commonly prescribed and over-the-counter medicines. The blood level of lithium is dependent on kidney function, and lithium has the potential to interfere with kidney and thyroid functions. The NPSA has developed supportive material for health professionals as well as a patient information booklet, lithium alert card, and a record book for tracking blood tests. The complete alert and links to the associated materials can be found at: www.nrls.npsa.nhs.uk/resources/type/alerts/?entryid45=65426.

Danger of withdrawing insulin from pen cartridge

A pharmacist received a call from a nurse who was concerned that a patient’s insulin pen did not deliver the correct dose of insulin. To identify the problem, the nurse took a standard insulin syringe, dialed the pen to 10 units, and injected the insulin into the syringe to measure how much would reach the patient. She found that the insulin syringe only contained 5 units. This was repeated twice with the same results. The pharmacist went to the nursing unit, repeated the experiment, and also got just 5 units. When laying the pen down on the table, the pharmacist noticed that an air bubble was visible. Knowing how that could affect insulin delivery from the pen, he obtained a new pen from stock and repeated the previous experiment. This time 10 units were measured in the syringe. The problem was traced to nurses using the pen cartridges as “mini” insulin vials by drawing the dose out of the pen cartridge with an insulin syringe. It’s a practice we’ve warned against because it’s known to lead to inaccurate dose measurement (www.ismp.org/Newsletters/acutecare/articles/20080508.asp).

When nurses are not sure how to use a pen, or encounter problems when using it, they may remove the pen cartridge and use it as if it was a vial. This can accidentally introduce air into the cartridge. Once any amount of insulin is withdrawn from the cartridge, it may no longer deliver the amount of insulin listed on the dispensing dial (and may also risk contamination of the remaining medication). In this instance, the patient was subjected to several injections and less effective blood glucose control because the pen was used in an unintended manner.

Cetacaine bottles with Luer connector

While Cetacaine liquid (benzocaine 14%, butamben 2%, tetracaine hydrochloride 2%) continues to be available in spray and gel forms, the widely used local anesthetic is now also available in a bottle with a dispenser cap that is compatible with any Luerlock syringe. The product catalog can be viewed at: www.cetylite.com/pdf/productcatalog.pdf

The new presentation allows dentists and other practitioners to draw up small amounts (liquid in excess of 0.4 mL is contraindicated) and attach a special applicator tip to reach periodontal pockets to provide local anesthesia for scaling and root planing, without need for an injectable local anesthetic.

Cetacaine liquid is not suitable for injection. Given the potential for mix-ups with unlabeled syringes, the ability to draw the liquid into a parenteral syringe should be cause for concern in any patient care area where systemic injections might be administered. See our October 22, 2009 issue http://www.ismp.org/Newsletters/acutecare/archives/Oct09.asp#22 - for a related article about accidental injection of oral products.)

In marketing materials, the manufacturer, Cetylite Industries, mentions that the liquid can be used for “other procedures requiring site-specific topical anesthesia to accessible mucous membrane.” This may place the product into an area where systemic injections are administered.

We’ve contacted the company to express our concern and suggest the use of a non-Luer connector, with directions to use the product with a nonparenteral syringe (oral or topical syringe). We also suggested including “Topical Use Only” labels with the product to facilitate proper labeling. Our best advice, though, would be to avoid this form of Cetacaine if there’s any chance it might wind up in area where patients may receive systemic injections.