Avoid Using the Error-Prone Abbreviation “TPA”; Unexpected Painful Breath; Mix-ups among “V” Drugs; Brintellix-Brilinta: Name Change Needed

Abstract

These medication errors have occurred in health care facilities at least once. They will happen again—perhaps where you work. Through education and alertness of personnel and procedural safeguards, they can be avoided. You should consider publishing accounts of errors in your newsletters and/or presenting them at your inservice training programs. Your assistance is required to continue this feature. The reports described here were received through the Institute for Safe Medication Practices (ISMP) Medication Errors Reporting Program. Any reports published by ISMP will be anonymous. Comments are also invited; the writers’ names will be published if desired. ISMP may be contacted at the address shown below. Errors, close calls, or hazardous conditions may be reported directly to ISMP through the ISMP Web site (www.ismp.org), by calling 800-FAIL-SAFE, or via e-mail at ismpinfo@ismp.org. ISMP guarantees the confidentiality and security of the information received and respects reporters’ wishes as to the level of detail included in publications.

Avoid Using the Error-Prone Abbreviation “TPA”

Problem

The US Food and Drug Administration (FDA) and ISMP continue to receive reports of wrong drug errors between Activase (alteplase) and TNKase (tenecteplase). The reported errors are related to the use of the abbreviations “t-PA” or “TPA.” In June 2015, ISMP received a report of a wrong drug error where a nurse typed “t” in the automated dispensing cabinet and selected tenecteplase on the screen instead of alteplase because “alteplase was commonly referred to as tPA.” ¹

Activase is a tissue plasminogen activator that the FDA approved in 1987 for use in the management of acute myocardial infarction and later for acute ischemic stroke and pulmonary embolism indications. TNKase, also a tissue plasminogen activator, was FDA approved in 2000 for the management of acute myocardial infarction only. Because Activase was the first tissue plasminogen activator approved, it has commonly been referred to as “t-PA” or “TPA” by health care providers. Unfortunately, the use of the abbreviations “t-PA” or “TPA” has led to confusion with the use of shorthand “TNK” for TNKase, leading to wrong drug errors.

Two cases of wrong drug errors resulting in mix-ups between Activase and TNKase were initially reported in the May 29, 2003, ISMP Acute Care newsletter. ² The errors stemmed from medication orders that were written as an initial dose of “t-PA 8 mg IV” and “t-PA 7 mg IV” for an acute ischemic stroke. Nurses involved in these cases assumed t-PA was shorthand for TNKase and gave patients 8 mg and 7 mg of TNKase, respectively, instead of the intended drug, Activase.

Since the initial reports, we continue to receive cases of confusion between these 2 products. In 2014, a patient who experienced an ischemic stroke received TNKase instead of the intended Activase. Although it was unclear whether the abbreviation “tPA” was used in the order, the reporter attributed the wrong drug error to confusion between the abbreviations “TNK” and “TPA” because Activase was frequently called “TPA.”

Wrong drug errors between TNKase and Activase can be attributed to the fact that both have similar settings of use (emergency departments, critical care areas) and patient populations (cardiac events). However, the use of the abbreviation “TPA” is also a significant contributing factor that led to the wrong drug errors. The abbreviations “TPA,” “tape,” and “TNK” are listed on the Drug Name Abbreviation section of the ISMP List of Error-Prone Abbreviations, Symbols, and Dose Designations. ³ Despite ISMP's recommendations ⁴ to avoid abbreviating drug names, the continued use of the abbreviation “TPA” has led to confusion between Activase and TNKase. Likewise, the continued use of the abbreviation “TPA” may also stem from frequent but inappropriate use of the abbreviations “tPA,” “TPA,” and “rt-PA” in published medical literature when referring specifically to alteplase. ⁵

The consequences of giving patients with ischemic stroke TNKase instead of Activase include the failure to administer a drug of known effectiveness (Activase) and the potential for overdose. The dose for Activase (0.9 mg/kg) ⁶ is often higher than the maximum labeled TNKase dose for acute myocardial infarction. An overdose of TNKase may increase the risk of intracranial hemorrhage, retroperitoneal bleed, extended hospitalization, and death.

Recommendations

Since Activase, TNKase, and Retavase (reteplase) are all tissue plasminogen activators, referring to any one of these products as “TPA” may lead to confusion regarding the intended product. Therefore, we recommend the following:

• 1.Never use abbreviations for drug names.
• 2.Do not use the abbreviation “TPA.” Refer to all 3 tissue plasminogen activators by their brand names (Activase, TNKase, Retavase), established/generic names (alteplase, tenecteplase, reteplase), or both in all verbal and written communications.
• 3.Do not use “TNK” as an abbreviation for TNKase.
• 4.Remove the abbreviation “TPA” and “TNK” from all standardized order sets, computerized provider order entry screens, and treatment protocols to avoid confusion.
• 5.Since Activase, but not TNKase or Retavase, is approved for use in the management of ischemic stroke and pulmonary embolism, prescribers should state the indication on prescription orders to help ensure the correct drug is ordered and dispensed.
• 6.Consider the use of alerts for TNKase in electronic prescriber order entry systems and/or automatic dispensing cabinets (eg, “Warning: Frequently confused with Activase [alteplase], verify the correct drug for the appropriate indication”).

An FDA video on this topic is available at: http://www.medscape.com/viewarticle/850514

FDA Advise-ERR was provided by Tingting Gao, PharmD, BCPS, Safety Evaluator, and LT Alice Tu, PharmD, Team Leader of FDA's Office of Surveillance and Epidemiology, Division of Medication Error Prevention and Analysis. Doctors Gao and Tu previously served as FDA/ISMP Safe Medication Management Fellows.

Unexpected Painful Breath

When teaching patients about the proper use of an inhaler, be sure to emphasize the importance of recapping the device after use. We were reminded of this recently when reading BMJ Case Reports. A woman accidentally inhaled a small earring while using her asthma inhaler, which was uncapped and stored in her purse (http://casereports.bmj.com/content/2015/bcr-2014-207398). As she inhaled the medicine, she felt a painful scratch in her throat and started coughing blood. She was taken to the emergency department, where the earring was removed from her lung. If the inhaler's cap had been in place, the loose earring in her purse would not have gotten into the inhaler.

Another event was reported in April 2015, in England (http://www.mirror.co.uk/news/uk-news/asthmasufferer-chokes-death-after-5446455). A woman used her inhaler and suddenly felt something shoot to the back of her throat. She began gasping for air and spitting up blood. She ran outside, and a neighbor came to her rescue and called emergency medical services. The woman eventually coughed out a fake nail that had been part of a set she had worn weeks ago. In this case, the inhaler's cover had been in place before use, so the nail had probably lodged in the inhaler when she was using it when wearing the nails.

Tell patients to always inspect the inhaler thoroughly before use to ensure that there are no unwanted objects within the inhaler. Also be sure to have them replace the inhaler cap after every use. Some of the newer inhalers have an attached cap. If a foreign object enters the inhaler, it places the person at risk of breathing in the object and causing choking or severe respiratory difficulties.

Mix-Ups among “V” Drugs

Confirmation bias likely played a role in a recent pharmacy admixture error in which VFEND (voriconazole) 200 mg diluted in 0.9% sodium chloride was prescribed but Venofer (iron sucrose) 200 mg diluted in 0.9% sodium chloride was prepared and dispensed. Earlier in the day, an experienced pharmacy technician had correctly prepared a Venofer 200 mg dose for another patient, and a pharmacist had checked it prior to dispensing. Later in the day, the same technician picked up a newly printed label to begin preparing the next IV admixture. The label stated “voriconazole (VFEND) 200 mg in sodium chloride 0.9%,” but the technician misread the label as Venofer 200 mg in sodium chloride 0.9%. She quickly noticed the letters common to both brand names – V, F, N, and E – and the 200 mg dose, and her mind immediately thought of the admixture, Venofer, which she had prepared earlier in the day.

Believing she had the correct product in mind, normal human cognition caused her to stick to her initial assumption (called an anchoring heuristic) and to avoid pursuing alternative thoughts on what the label said (called premature closure). Once confirmation bias kicked in, the brain rejected any disconfirming evidence that would have alerted her to the error. Similarly, the pharmacist checking the product suffered from confirmation bias. He immediately saw the brown-tinted solution in the bag and thought of the Venofer infusion he had checked earlier in the day. Thus, when reading the label, he too saw Venofer, not VFEND, 200 mg.

People have a tendency to judge the likelihood of properly identifying products by how easily the idea sprang to mind (called availability heuristic). In this case, the brown-tinted solution quickly sealed the pharmacist's belief that the label said Venofer, not VFEND. Multitasking was another factor that contributed to confirmation bias, as the pharmacist was trying to cover two very busy areas in the pharmacy during a lunch break.

This patient was critically ill, and omission of the antifungal medication could have been serious. Also, administration of unintended iron could have resulted in a hypersensitivity reaction. Fortunately, an astute nurse questioned why the antifungal medication was brown, and the error was detected.

The pharmacist and technician have suggested omitting the brand names on labels for Venofer and VFEND, along with one additional IV infusion with a typical 200 mg dose that could be misread—Vimpat (lacosamide), an anticonvulsant. The generic names of these 3 products are very different and less likely to be mixed up. However, the drug name on the label is also what appears on order entry screens and medication administration records, so be sure to consider how this strategy would affect physicians and nurses before making the change. One important strategy to prevent errors with medications with similar names and doses is to utilize barcode scanning of products during the IV admixture process to prevent a drug selection error.

Brintellix-Brilinta: Name Change Needed

We recently received a report about an elderly patient who was harmed as a result of a mix-up between Brintellix (vortioxetine), used for major depressive disorders, and Brilinta (ticagrelor), an antiplatelet agent used in patients with acute coronary syndrome. The patient was given a prescription for Brilinta 90 mg, but Brintellix 10 mg was dispensed. The patient fell and was admitted to a hospital after taking Brintellix for 9 days. The fall resulted in a periorbital hematoma (black eye) but no fractures. The dispensing error occurred in a pharmacy where the 2 drugs were stored side-by-side, and the wrong container was selected. It is not clear if barcode scanning was available. If scanning was available and the prescription been entered into the pharmacy computer system accurately, it is likely that scanning would have prevented the mix-up.

Errors can also happen when selecting medications during order entry and verification. Typing the first few letters of the brand name may lead to either one name or both appearing on the screen, and the wrong item could be selected.

We added these names to the 2015 ISMP List of Confused Drug Names (www.ismp.org/sc?id=606;pharmacy wall chart: http://store.thomasland.com/confused_drug_names_2015-2.aspx). The FDA also warned health care professionals and patients about Brintellix and Brilinta errors (http://www.fda.gov/Drugs/DrugSafety/ucm456341.htm) in July 2015, noting that over 50 reports had been received, most of which were sent by the manufacturer.

Takeda, the company that sells Brintellix, has initiated electronic messages to pharmacists about the risk of mix-ups. Dose limits in order entry systems can help detect mix-ups if 90 mg of Brilinta is ordered but Brintellix is selected in error. Given the large number of ongoing error reports and the potential for patient harm, a name change for one of these products is in order. Brintellix was approved in 2013. Brilinta was approved in 2011. Usually, when a name is changed, we have observed that it is by the company whose product was approved most recently.