Sentinel Event Alert The Joint Commission http://www.jointcommission.org/SentinelEvents/SentinelEventAlert/

Issue 41, September 24, 2008

Preventing errors relating to commonly used anticoagulants 
 

Reports of accidental deaths and overdosing due to the improper use of anticoagulant drugs have received significant public attention. Anticoagulants have been identified as one of the top five drug types associated with patient safety incidents in the United States.(1)  In the United Kingdom, anticoagulants are one of the classes of drugs commonly associated with fatal medication errors. (2)

The Joint Commission’s Sentinel Event Database includes 446 medication-related sentinel events (9.3 percent of all events) reported from January 1997 through December 2007, with 7.2 percent (32) of these involving anticoagulants; of those, two-thirds (21) involve heparin* (see sidebar for more data). According to the United States Pharmacopeia MEDMARX  database, a total of 59,316 medication errors related to anticoagulants were reported to the MEDMARX program from 2001 to 2006 (these data do not include errors involving heparin lock flush). Nearly 60 percent of these errors reached the patient and nearly 3 percent resulted in harm or death. Performance error (e.g., administration) is the most common cause of adverse events relating to anticoagulant medications.  

The anticoagulants cited most frequently in medication error reports are unfractionated heparin, warfarin and enoxaparin (classified as low molecular weight heparin, LMWH)*, according to MEDMARX and a hospital study. (3)  These are also the most commonly used anticoagulants and the focus of this Alert. According to MEDMARX, in 2005, enoxaparin errors were associated with four patient deaths and two cases of permanent harm. Other anticoagulant errors have been associated with the concurrent use of heparin and enoxaparin and with argatroban and lepirudin. 
 

Contributing factors

Patients under consideration for receiving anticoagulant drugs must be carefully screened for contraindications and drug interactions. While receiving anticoagulants, patients must be monitored closely to ensure effectiveness and to prevent side effects or overdosing. Heparin and warfarin in particular have narrow therapeutic ranges and a high potential for complications (4), so there is a greater risk of patient harm. (5) The following factors contribute to medication errors involving anticoagulants:

Lack of standardization for the naming, labeling and packaging of anticoagulants creates confusion. For example, heparin flush syringes have been confused with LMW heparin syringes. In addition, other, lesser-known anticoagulant drug names exist (e.g., enoxaparin, dalteparin, tinzaparin) and are used less commonly, which can result in duplicate medication orders and erroneous dosing.
Keeping current with different dosing regimens for various patient populations, newer assay methods, the expanding lists of drug interactions, and the potential reversal strategies can be a challenge for providers—especially those who infrequently prescribe or administer anticoagulants. (6)
The specific and individualized instructions and monitoring information (for example, dose adjustments, lab values, changing patient condition) that accompany the prescribing and administration of anticoagulants may fail to get documented or communicated during transfers and hand-offs. (7)
Neonates and other pediatric patients are problematic to treat, specifically because the medications are formulated and packaged primarily for adults. (8)
 

 
Risk reduction strategies

Health care organizations that dispense or administer anticoagulant medications can prevent errors relating to anticoagulants by implementing specific risk reduction strategies. Since the management of anticoagulants is interdisciplinary, any risk strategies should be implemented by all staff who manage anticoagulants, which can include physicians, nurses, pharmacists, dieticians, and case managers. Specific guidelines regarding anticoagulant management have been developed by the United Kingdom’s National Patient Safety Agency, (2) the Institute for Safe Medication Practices, (9) and the Institute for Healthcare Improvement. (10)  These guidelines stress improving staff communication and access to information; implementing close pharmacy oversight and involvement; and enhancing patient education. Research shows there is a significant reduction in the risk of thromboembolic events and death among patients who manage their anticoagulation therapy compared with those who rely solely on their doctor to monitor their treatment. (11,12)  In addition, organizations may consider:

Implementing a pharmacist-managed anticoagulation service. In addition to helping discharged patients receiving warfarin therapy, this service can assist staff caring for patients on