Patient Errors and Adverse Events

Article Tools

• Email This
• Text Size
• Print This
• Rate This

Tuesday, March 18, 2008

PTINR.com Staff

Patient errors compromise patient safety and can result in serious injury

Prescription management can be challenging for older adults. A study of more than 30,000 patients aged 65 years and older revealed that medication errors could be classified into one of six categories, and that patient errors were associated with age.1 The study was published in February 2007 issue of the Journal of American Geriatrics Society.

Safety and medical outcomes can be significantly compromised due to medication errors made by the patient.  Specifically, 19% of patient-related errors involved the management of anticoagulants, including warfarin (Coumadin ®).1 The definition and frequency of adverse events due to patient error in anticoagulation management are discussed below.

Filling the prescription

There were no patients (0%) who failed to fill their prescription for anticoagulants. In contrast, patients taking diuretics were least likely to fill their prescription.1 

Administering the drug

Patients make mistakes in the administration of anticoagulant therapy when they fail to take the right medication, in the correct dosage, at the scheduled time.  This type of patient error was most problematic for anticoagulation patients, as 42% of patient errors were related to drug administration during the 1-year study.1

Following clinical advice

21% of patient errors with anticoagulation management were associated with difficulty following healthcare provider instructions.  Only patients taking hypoglycemic medications (43%) or analgesics (55%) had more trouble with clinical orders than those taking an anticoagulant.1

Modifying the regimen

For those advised to self-monitor their anticoagulant, mistakes in dosage modification fall into this category. 29% of medication errors occurred in modifying warfarin dose.  Patients on hypoglycemic, cardiovascular, and diuretic medications all made more mistakes in dosage modification than those on anticoagulation therapy.1

Reporting clinical information

Errors in this category included the failure to notify a healthcare professional of a side effect and/or use of over the counter medications.  Within the scope of this study, no errors (0%) by anticoagulant patients could be attributed to poor reporting of clinical information.1 Other studies have documented that patients under-report the use of dietary supplements, as well as some over the counter medications.

Adhering to follow-up

Adherence to follow-up included keeping lab and office appointments.  29% of anticoagulation medication errors resulted from missed lab and/or office appointments. Anticoagulation patients were least likely to successfully adhere to follow-up instructions.1 Home INR testing is a proven method to support more frequent testing, which results in increased time in target range.2

The authors suggested that technology will provide solutions to many problems that lead to patient medication error. Today, portable coagulation monitors are already available for patient self-testing. Well-trained patients, and consistent communication of home test results to healthcare teams, will be necessary for the best achievable warfarin management. With more than 24 million prescriptions dispensed for warfarin (2006)3, improvement in warfarin safety will require discipline and coordination between physician and patient on a large scale.