Anticoagulation Management Service: Safer Care, Maximizing Outcomes

​​​Abstract

PA-PSRS has received hundreds of Serious Event reports between June 2004 and January 2008 associated with anticoagulation therapy with outcomes having hematologic effects from thrombocytopenia to hemorrhage. The indications, dosages, strengths, and pharmacokinetics for anticoagulants are quite variable, requiring extra attention to prescribing, dispensing, administering, and monitoring the effects of these medications. The complexity of anticoagulants has resulted in patient safety compromise. Healthcare organizations have increasingly recognized the benefits of anticoagulation management services (AMS) in the inpatient and outpatient settings. The benefits of an AMS program include a reduction in mortality rates and bleeding complications, decreased adverse drug events, including medication errors and shortened hospital stays, thereby producing safer patient care. The key components in AMS program development include defining the rationale for AMS development, outlining issues associated with anticoagulants, defining AMS scope of service and infrastructure, and outlining AMS program metrics.

Introduction 

PA-PSRS has received hundreds of Serious Event reports between June 2004 and January 2008 associated with the prescribing, dispensing, administering, and/or monitoring of anticoagulation therapy (see Table). Patient outcomes included hematologic effects from thrombocytopenia to hemorrhage; many patients required transfusions; some patients died.

Anticoagulation medications require comprehensive dosing and monitoring strategies to minimize the risks associated with their use to produce optimal patient outcomes.¹ Healthcare organizations and physicians have increasingly recognized the benefits of an anticoagulation management service (AMS) in the inpatient and outpatient settings. Consider the following reports submitted to PA-PSRS surrounding issues with anticoagulation therapy:

Critically ill patient diagnosed with spontaneous retroperitoneal hematoma. Physician discontinued heparin, administered vitamin K and ordered [hematocrit and hemoglobin] every six hours. [Twice], blood specimens were not collected by the nurse. The patient arrested and died. Hemoglobin per [arterial blood gases] at time of arrest was 5.

Patient was admitted after a fall at home; found to have an acute [myocardial infarction] while in the [emergency department (ED)]. Heparin bolus and drip ordered. The required heparin order form was not used. The order was apparently not weight based. No calculations or double checks were done. The patient was transferred to the [intensive care unit (ICU)] when drip was hung, heparin was set to run at to-keep-open rate. Patient received [heparin] 25,000 units in a three hour [span].

Patient was noted on [admission] to have low probability of [heparin induced thrombocytopenia (HIT)] but blood work showed antibodies to heparin. Heparin 5,000 units [subcutaneously, two times per day] was ordered for the patient [for 7 days] when the patient was transferred to the [patient care unit]. [Two days later], the patient collapsed and was transferred to the ICU with diagnosis of pulmonary emboli. The heparin allergy was not placed in the electronic record until [the transfer to ICU].

The Institute of Medicine stresses the importance of adopting an interdisciplinary approach to patient care by encouraging healthcare professionals to establish teamwork, communication, and cooperation.² The Joint Commission’s 2008 National Patient Safety Goal 3E to improve the safe use of medications includes the new requirement to reduce the likelihood of patient harm associated with anticoagulation therapy medications such as heparin (unfractionated), low-molecular-weight heparin, warfarin, and other anticoagulant drugs.³ These medications require comprehensive dosing and monitoring strategies to minimize the risks associated with their use and to maximize patient outcomes.

U.S. Pharmacopeia lists anticoagulants heparin, warfarin, and enoxaparin as high-risk medications and among the top 12 drugs associated with medication errors.⁴ High-risk medications have greater probability of causing significant harm than other medications, when used incorrectly. Standardizing anticoagulation therapy can help to reduce bleeding complications and decrease the number of adverse drug events, including medication errors. Optimally, this will produce safer care, which contributes to the reduction in mortality and shortened length of hospital stays.

Literature Supports Anticoagulation Management Services

A randomized controlled study by Wilson et al. ⁵ compared outcomes when anticoagulation therapy was managed by anticoagulation clinics versus primary care physicians. The rates of thromboembolic, major hemorrhagic events, and patient satisfaction were measured between the two groups. Eighty-six percent of the time, patients in the anticoagulation clinics were within the international normalized ratio (INR) expanded therapeutic range while patients in the family physician group were within expanded therapeutic range 77% of the time. The most significant difference between the two groups was that patients managed by anticoagulation clinics resulted in fewer high-risk INR values of less than 1.5 or greater than 5. Differences in major bleeding events, thromboembolic events, and mortality rates between the two groups were not significant. Patient satisfaction was much also higher with the anticoagulation clinics than with routine care. The results indicated that anticoagulation clinics provided slightly better oral anticoagulation management than family physician groups.⁵

A retrospective, observational cohort study by Witt et al.⁶ measured the effects of a centralized clinical pharmacy anticoagulation service (CPAS) on the outcomes of anticoagulation therapy. The intervention group’s anticoagulation therapy was managed by a centralized, telephonic CPAS, while the control group was managed by primary care physicians. Thirty-nine percent fewer patients in the CPAS group experienced anticoagulation therapy complications than patients in the control group.⁶ Sixty-three percent of the CPAS group had INR levels within target range compared to 55.2% of those patients receiving care from personal physicians.⁶ The CPAS were managed by pharmacists and included the use of a computerized patient monitoring system that identified when patients failed to return for subsequent INR testing. This study also supported the idea that a coordinated and systematic approach to an AMS may be more important than the method of management (i.e., telephonic, in person).

A retrospective cohort study by Chamberlain et al.⁷ linked record review (including outpatient, inpatient, and ED records) between two groups of patients: those treated in a traditional clinic and those treated in an AMS. The AMS group had better anticoagulation control than the traditional care group.⁷ There was also less variation with INR target range with the AMS than with the traditional clinic. INR testing was conducted more frequently with the AMS, as was follow-up care, which included patient education. These findings emphasize the effects of a shared AMS to include clear clinical guidelines and patient information exchange.^7,8

In a retrospective analysis of more than 700,000 Medicare patients, institutions with inpatient anticoagulation services had shortened lengths of stay, lower Medicare charges, and decreased rates of bleeding and transfusion complications compared to institutions without such services. ⁹ This was the first large-scale study that evaluated the impact of pharmacist-managed anticoagulation services on healthcare outcomes.⁹

Given the results of these studies, leaders should consider implementing AMS in their organizations. Ideally, creating an AMS that extends along the continuum of care by incorporating inpatient and outpatient services will provide patients with optimal care from the first day of anticoagulation to the completion of therapy. ¹⁰

Several U.S. hospitals have implemented integrated AMS programs over the past decade.^1,10-12 Other hospitals have implemented AMS only for patients outside the tertiary care settings.^3,13 All program types have the same ultimate goal—to provide safer care and optimize patient outcomes.

The following PA-PSRS reports that illustrate Serious Events that occurred in the ordering, dispensing, administrating, and monitoring of anticoagulation medications.

[A clinic patient presented] with nontherapeutic [prothrombin (PT)/INR]. Results called to physician office, but the Coumadin® dose was not adjusted. The patient required hospitalization at another facility for PT/INR regulation.

The medication [order] expired, and the physician did not renew medication. Medication dropped off computer screen due to nonrenewal.  Patient was transferred to ICU. Staff did not realize patient had been getting Lovenox®.  Patient developed a [pulmonary embolism two weeks later] due to not being on anticoagulants.

An initial bolus of heparin and heparin nomogram protocol were calculated on an incorrect patient weight. The heparin was calculated in the ED on an estimated patient weight of 130 kilograms. The patient was transferred to the [patient care area] where the [actual] weight was measured as 103 kilograms. The physician was notified immediately and the [partial thromboplastin (PTT)] was greater than 150. Heparin was stopped. The patient developed [petechiae]. Protamine was administered in addition to additional laboratory testing.

Patient admitted and medication orders included Coumadin® 2.5 mg orally daily-hold for INR greater or equal to 3.5, and Lovenox 40 mg subcutaneously daily. No PT/INR ordered during stay until [three days later] when the patient was noted to have complications of bleeding. The physician was notified of elevated PTT and bleeding and then ordered PT/INR.

Nurse recorded wrong PTT result and adjusted heparin rate/protocol. Adjustment scanned to pharmacy and pharmacist did not confirm correct PTT result. Nurse did not obtain co-signature of second nurse [which was] required [per] policy for heparin rate adjustments.

Key Components to Consider When Developing an Anticoagulation Management System

Patient safety committees should consider assessing anticoagulation safety to help define their organization’s needs before an AMS development. This self-assessment allows facilities to outline the positive impact that an AMS program will have to provide safer care and maximize patient outcomes. An individualized AMS is based on the organization’s specific needs, resources, and experiences and includes the following:

Define Rationale for AMS Development

• Develop a multidisciplinary AMS program committee comprising physicians, pharmacists, nurses, clinical laboratory, and information technology staff.^1,3,10,11
• Evaluate current anticoagulation processes to clearly define the future AMS program development, targeting those patients with the greatest need.^1,10,12  Review prior Incidents (near misses) and Serious Events related to anticoagulation medications. This data will provide additional justification for AMS development.

Outline Issues Associated with Anticoagulation Medications

• Review literature relating to the use of anticoagulation agents. Using medical record audit, review your organization’s trends in timeliness to achieve therapeutic anticoagulation levels, laboratory results monitoring capabilities, the use of overlap anticoagulants (including anticoagulation management when patients require an invasive procedure), and adequacy of anticoagulation therapy at discharge. These measurable outcomes demonstrate the difficulty in effectively managing anticoagulation therapy.^12,14 
• Standardize the use of anticoagulants.^10,15 This may include but is not limited to standardization of anticoagulation medications concentrations; formulary limits; use of only commercially or pharmacy filled heparin flushes and intravenous solutions; use of a pharmacy profiled, reconciled computerized prescriber order entry with alerts for duplicate therapy, drug contraindication, and drug and food interactions. Other considerations may be the use of automated dispensing cabinets that interface with pharmacy information systems with limited or no override capabilities, use of infusion pumps with drug libraries, and standard labeling techniques.¹⁵ Use the electronic medication administration record to standardize the documentation of coagulation laboratory results before anticoagulation medication administration.

Define AMS Scope of Service and Infrastructure

• Determine team composition of AMS program. Some inpatient AMS programs are pharmacy-driven teams providing service for heparin therapy, while other AMS programs provide total management for all anticoagulant therapies through a consultative process.¹² Provide adequate staffing depending on program composition.^10,11
• Create communication and documentation systems that extend along the continuum of care and incorporate both the inpatient and outpatient AMS.^3,8-11
• Develop policies, guidelines, written protocols, heparin dosing algorithms, and safe scope of evidence-based practice, including supervision for physicians and pharmacists.^{1,3,9-11,14,16}
• Develop formal anticoagulation competencies for physicians, pharmacists, and nurses to assess baseline and ongoing knowledge about anticoagulation therapy, thromboembolism, HIT, and allergies including a competency demonstration process to assess ability to apply safe practice concepts.^9,11-13 Identify key interdisciplinary champions.¹⁰
• Use an electronic tracking system to integrate and bridge medical records of outpatient- or community-based programs, inpatient medical records, laboratory studies, and medication records.^3,8-11
• Develop a well-designed anticoagulation patient and family educational program to help increase compliance and contribute to improved patient outcomes.¹⁴

AMS Program Metrics

• Define AMS program outcomes for future measurement. Consider measurement of target INR levels, INR levels associated with hemorrhagic complications and thromboembolism rates, deaths, minor and major bleeding episodes, use of ED visits and hospital admissions associated with anticoagulation problems, hospital length of stay, patient satisfaction, and reimbursement.^12,14
• Develop a quality program that monitors and generates annual reports (more often as deemed necessary) to document metrics, to improve performance including error reduction rates, and to manage any unanticipated risks.^9-12,14

Notes

1. Phillips KW, Wittkowsky AK. Survey of pharmacist-managed inpatient anticoagulation services. Am J Health-Syst Pharm 2007 Nov 1;64(21):2275-8.
2. Kohn LT, Corrigan JM, Donaldson MS, eds. To err is human: building a safer health system. Washington (DC): National Academy Press, 2000.
3. The Joint Commission. Reducing anticoagulation- related adverse drug events: closely monitoring and managing risks for patients on warfarin. Jt Comm Perspect Patient Saf 2006 Jul;6(7):3-4.
4. U.S. Pharmacopeia. Top 50 drug products* associated with medication errors [online]. [cited 2008 June 18]. Available from Internet: http://.usp.org/hqi/patientSafety/resources/top50DrugErrors.html.
5. Wilson SJ-A, Wells PS, Kovacs MJ, et al. Comparing the quality of oral anticoagulant management by anticoagulation clinics and by family physicians: a randomized controlled trial. CMAJ 2003 Aug;169(4):293-8.
6. Witt DM, Sadler MA, Shanahan RL, et al. Effect of a centralized clinical pharmacy anticoagulation service on the outcomes of anticoagulation therapy. Chest 2005 May;127:1515-22.
7. Chamberlain MA, Sageser NA, Rutz D. Comparison of anticoagulation clinic patient outcomes from traditional care in a family medicine clinic. JABFP 2001 Jan-Feb; 14(1):16-21.
8. Holm T, Lassen JF, Husted SE, et al. A randomized controlled trial of shared care versus routine care for patients receiving oral anticoagulant therapy. J Int Med 2002 Oct;252(4):322-31.
9. Bond CA, Raehl CL. Pharmacist-provided anticoagulation management in United States hospitals: death rates, length of stay, medicare charges, bleeding complications, and transfusions. Pharmacotherapy 2004 Aug;24(8):953-63.
10. Dager WE, Gulseth MP. Implementing anticoagulation management by pharmacists in the inpatient setting. Am J Health-Syst Pharm 2007 May 15;64:1071-9.
11. Schneider BL, Gulseth MP, Cusick MA, et al. Computer program to assist pharmacy management of an inpatient warfarin dosing service. Am J Health-Syst Pharm 2005 Nov 15;62:2393-6.
12. Viercinski J, Thomson L, Wilson J, et al. Establishing an inpatient anticoagulation service: a step by step review. J Thromb Thrombolysis 2008  Feb;25(1):67-71.
13. Bungard TJ, Archer SL, Hamilton P, et al. Bringing the benefits of anticoagulation management services to the community. Can Pharm J 2006 Mar-Apr;139(2):58-64.
14. Ansell JE, Buttaro ML, Thomas OV, et al. Consensus guidelines for coordinated outpatient oral anticoagulation therapy management. Ann Pharmacother 1997 May;31(5):604-15.
15. Institute for Safe Medication Practices (ISMP). ISMP’s medication safety self assessment® for antithrombotic therapy in hospitals [online]. 2005 [cited 2008 Jul 18]. Available from Internet: http://www.ismp.org/selfassessments/asa2006/ASAISMPAssessment.pdf.
16. Weitz JI, Hirsh J, Samama MM. New anticoagulant drugs: the seventh ACCP conference on antithrombotic and thrombolytic therapy. Chest 2004 Sep;126(3):265S-86S.