avoiding pitfalls of anticoagulation therapy

JOURNAL OF HEALTHCARE RISK MANAGEMENT • VOLUME 27, NUMBER 2 35

Patient Safety

Avoiding pitfalls of anticoagulationtherapy

Antithrombotic therapy poses a significant risk of litigation owingto the risk of devastating outcomes from both the condition forwhich the therapy is necessary and the therapy itself. Using acase-based approach, this article illustrates how evidence-basedguidelines, documentation, and patient communication can potentiallyreduce the likelihood of errors associated with antithrombotic therapy.

INTRODUCTION

Without sufficient prophylaxis, which usually includes the use of anticoagulantsin high-risk settings, many patients will develop venous thromboembolism(VTE), including fatal pulmonary embolism (PE). However, anticoagulationtherapy itself places the patient at risk for bleeding, particularly hemorrhagicstroke or intracranial hemorrhage.

This is the “antithrombotic dilemma”: the patient requiring antithrombotictherapy is at risk from both the therapy itself and the underlying condition forwhich the therapy is necessary.(1) Consequently, antithrombotic therapy is aconsiderable concern for risk management.

The potential for legal liability with antithrombotic therapy begins when thepatient is first considered or should have been considered for antithromboticprophylaxis.(1) Because most hospitalized patients have VTE risk factors, theAmerican College of Chest Physicians’ (ACCP) evidence-based consensusguidelines for VTE prevention recommend risk stratification upon admissionfor every patient.(2) The guidelines provide graded recommendations for avariety of antithrombotics in different patient populations based on the qualityof clinical evidence available.(2) Thus, once the VTE risk level is determined, if VTE prophylaxis is warranted, the guidelines can help to determine whichanticoagulant is most appropriate.(3)

Evidence-based guidelines reflect the standard of practice in VTE prophylaxis;therefore, increased awareness of and adherence to guideline recommendationscan reduce physician and hospital liability. However, guideline adherence doesnot guarantee protection because guidelines are not likely to be the only factorin determining liability.(1, 4) Additional methods for reducing the risk of liabilityassociated with antithrombotic therapy include documentation of risk stratification,such as a VTE risk checklist used to assess the risk for VTE in all patients uponadmission (see Table on page 38, for example), and open communication witheither the patient or the patient’s family regarding the risks and benefits ofVTE prophylaxis.(1)

By Stanley A. Nasraway, MD, FCCM

continued next page

41377bdyfnl:41377 8/31/07 2:33 PM Page 35

36 JOURNAL OF HEALTHCARE RISK MANAGEMENT • VOLUME 27, NUMBER 2

In this article, examples of patients who failed to receiveprophylaxis for VTE and had a poor outcome will be usedto illustrate how evidence-based guidelines, documentationand patient communication can potentially reduce thepossibility of errors associated with VTE prophylaxis. The case-based format was used because it is importantfor risk managers to understand where errors in VTEmanagement can occur and where there are opportunitiesto reduce risk. Although based on actual occurrences, the cases that follow are fictional.

CASE 1

A 38-year-old woman who was obesewith a history of kidney stones presented with sepsis, acute renalfailure and dehydration. She wasadmitted to the intensive care unit(ICU) of a teaching hospital and acentral venous catheter was inserted.Mechanical VTE prophylaxis withintermittent pneumatic compression(IPC) was ordered; however, theorder was never carried out. Threedays after admission the patientdied in severe respiratory failure.Autopsy revealed the probable cause of death to be alarge embolus in the left pulmonary artery. The familysubsequently brought a malpractice suit against thetreating physician and hospital.

The incidence of deep vein thrombosis (DVT) withoutprophylaxis in medical patients is approximately 10 percentto 20 percent.(2, 5, 6) In acutely ill medical patients whohave been admitted to the hospital, are bedridden andhave one or more additional VTE risk factors, prophylaxiswith low-dose unfractionated heparin (UFH) and low-molecular-weight heparin (LMWH) is recommendedwith the strongest recommendation (Grade 1A).(2)Mechanical prophylaxis (i.e., graduated compressionstockings or IPC) is recommended only when anticoagu-lation is contraindicated.(2)

This case study’s hospitalized patient was a candidate for VTEprophylaxis because she was acutely ill and had additionalVTE risk factors, including sepsis, central venouscatheterization and body mass index greater than 30. The potential risk for VTE was considered in this patientas evidenced by the order for IPC; however, the order wasnever implemented.

Three main factors increased the risk of litigation in thiscase: 1) the physician failed to ensure that his order wascarried out, 2) the IPC order did not adhere to the ACCPguidelines regarding the method of prophylaxis and 3) therewas no documentation regarding VTE risk stratification,anticoagulation contraindication or why the order had not been implemented.

Although the patient may well have died conjointly fromsepsis, it is difficult to determine the relative role of sepsisvs. PE in causing death. In this case, increased awarenessof guideline recommendations and documentation ofVTE risk stratification (e.g., a VTE risk checklist) and therationale for lack of guideline adherence could have helpedto reduce the likelihood of litigation with a negative outcomefor the physician and hospital.

CASE 2

A 75-year-old man underwentcoronary artery bypass grafting(CABG) at a world renowned hospital; he developed atrial fibril-lation (AF) two days postoperatively.He was not given anticoagulationfor fear of bleeding complicationsassociated with CABG. Four daysafter the onset of AF he developedchest pain and shortness of breathand died within the hour. Autopsyrevealed the cause of death to be alarge embolus in the right pulmonary

artery. The family brought a malpractice suit againstthe chief of Cardiac Surgery and the hospital.

The incidence of post-CABG atrial arrhythmias includingAF, which is the most common, is approximately 11 percentto 40 percent,(8-11) and AF is a significant predictor ofstroke following CABG.(12) Data on the efficacy and safetyof anticoagulation therapy for episodes of AF followingCABG are lacking; however, recommendations have beenmade based on studies in patients with chronic AF.(13, 14)

The use of warfarin is recommended for AF occurringshortly after open-heart surgery and lasting more than 48 hours if bleeding risks are acceptable.(14) Heparin mayalso be considered in patients at particularly high risk forVTE.(13) Due to the lack of clinical studies, these recom-mendations are weak (based on observation only) andother options may be just as reasonable.

This patient was at moderate risk for thromboembolism dueto his age, new-onset AF and the presence of coronaryartery disease; therefore, anticoagulation would be recom-mended in this patient, as is noted in the guidelines. Chartreview showed no documentation of assessment for risk ofVTE or bleeding complications; thus, the rationale for thedecision not to anticoagulate in this at-risk patient, althoughpossibly reasonable given the weak recommendation foranticoagulation, was not elucidated. Lack of adherence toaccepted guidelines may not be as critical an issue in thiscase due to the lack of efficacy and safety data in this

It is important for riskmanagers to under-

stand where errors inVTE management canoccur and where there

are opportunities toreduce risk.

41377bdyfnl:41377 8/31/07 2:33 PM Page 36


specific patient population. However, lack of documenta-tion of consideration of VTE risk in a patient at risk forVTE increases the risk of litigation with a negative out-come for the physician and hospital.

Documentation, such as a VTE risk checklist, as well as open communication with the patient or his familyregarding the risks and benefits of anticoagulation, mayhave helped reduce the risk of litigation in this case.

CASE 3

A 76-year-old man with an obese body mass index of 44 kg/m2 and a 56-year smoking history presented witha fractured hip following a fall at home. He subsequentlyunderwent surgical repair of the hip fracture and didnot receive any form of VTE prophylaxis. On the fourthpostoperative day, he developed sudden respiratory distress and died within 15 minutes. Autopsy revealedthe cause of death to be a large embolus in the rightpulmonary artery. The family brought a malpracticesuit against the surgeon and hospital.

Without prophylaxis, hip fracture surgery (HFS) is associatedwith a 46 percent to 60 percent risk of DVT and 3 percentto 11 percent risk of PE.(2) Due to the high risk of VTEwithout prophylaxis, the routine use of anticoagulationfor at least 10 days and up to 28 to 35 days followingHFS is strongly recommended (Grade 1A).(2)Fondaparinux is the only agent with a Grade 1A recom-mendation for initial VTE prophylaxis following HFS.UFH, LMWH, and warfarin are also recommended, but the recommendations are not as strong because datawith these agents in this population are lacking.(2)

Hip fracture surgery and additional VTE risk factors presentin this patient, including age more than 60 years, morbidobesity, immobilization and a smoking history, placedhim in the highest risk category for VTE. Failure toadhere to the Grade 1A recommendation for prophylaxisfollowing HFS and lack of documented VTE risk stratifi-cation and rationale for withholding VTE prophylaxisresulted in significant risk for liability. A standard protocolfor VTE risk assessment in all hospitalized patients includinga VTE risk checklist (Table) could have prevented this sit-uation, in which prophylaxis was overlooked in a veryhigh-risk patient.

Increased awareness of guidelines, a standard protocol forVTE risk assessment, and improved documentation andcommunication with the patient and his family couldhave reduced the risk of litigation in this case.

CONCLUSION

Thrombosis is associated with significant risk of liabilitybecause both thrombosis itself and antithrombotic therapycan have devastating outcomes.

There is often a lack of adherence to antithrombotic therapyconsensus guidelines among practicing physicians.(15, 16)Because evidence-based guidelines are increasingly used inthe judicial system to establish standard of care, departurefrom evidence-based guidelines, coupled with lack of documentation of management rationale and poor patientcommunication, exposes the physician and hospital to risk.

Risk managers should encourage physicians to follow theACCP evidence-based guidelines and work with theirphysicians to plan conferences on risk management inthrombosis. New guidelines on the prevention and management of VTE were released in 2007; risk managerscould encourage their medical staff to distribute copies of the new guidelines.(17)

In addition, a standardized protocol for VTE risk stratificationupon admission that is based on guideline recommendationsis recommended by the National Quality Forum, a voluntaryconsensus standards-setting organization. A protocol, particularly one that includes a written checklist of VTE riskfactors (Table), can help improve guideline adherence,(3) can provide documentation of VTE managementrationale and may improve patient communication – all ofwhich can potentially reduce the risk of liability associatedwith antithrombotic therapy.

Risk managers should encourage staff to utilize VTE riskassessment checklists and to communicate with patients anddocument conversations and the rationale for decisions.

41377bdyfnl:41377 8/31/07 2:33 PM 7

38 JOURNAL OF HEALTHCARE RISK MANAGEMENT • VOLUME 27, NUMBER 2

Step 3: Total risk factor score (Exposing + Predisposing): ___

Step 4: Recommended prophylactic regimens for each risk groupLow risk (score = 1), Moderate risk (score = 2), High risk (score = 3-4), Highest risk (score = 5 or more)

Adapted with permission from Caprini J. Semin Hematol. 2001;38(2suppl5):12-19

Each risk factor represents 1 point

■■ Minor surgery

Each risk factor represents 2 points

■■ Major surgery*

■■ Immobilizing plaster cast

■■ Patients confined to bed >72 hours

■■ Central venous access

■■ Arthroscopic surgery


■■ Myocardial infarction

■■ Congestive heart failure

■■ Severe sepsis/infection


■■ Elective major lowerextremity arthroplasty

■■ Hip, pelvis, or leg fracture(<1 month)

■■ Stroke (<1 month)■■ Multiple trauma

(<1 month)■■ Acute spinal cord injury

(<1 month)

T A B L E

Example of Proposed VTE Risk Assessment Checklist for Surgical and Medical Patients (Caprini, 2001 #286)

Step 1: Exposing risk factors associated with clinical setting

*Operations in which the dissection is important or that last longer than 45 minutes, including laparoscopic procedures.Exposing risk factor score: ____

Step 2: Predisposing risk factors associated with patient

Clinical setting

■■ Age 40 to 60 years (1 point)

■■ Pregnancy or postpartum (<1 month; 1 point)

■■ Varicose veins (1 point)

■■ Inflammatory bowel disease (1 point)

■■ Obesity (BMI >25; 1 point)

■■ Combined oral contraceptive/hormonal replacement therapy (1 point)

■■ Age >60 years (2 points)

■■ Malignancy (2 points)

■■ Age >75 years (3 points)

■■ History of DVT/PE (3 points)

Inherited (3 points)

■■ Factor V Leiden/activated

■■ Antithrombin III deficiency

■■ Proteins C and S deficiency

■■ Dysfibrinogenemia

■■ Homocysteinemia

■■ 20210A prothrombin mutation

Acquired (3 points)

■■ Lupus anticoagulant

■■ Antiphospholipid antibodies

■■ Myeloproliferative disorders

■■ Disorders of plasminogen and plasmin activation

■■ Heparin-induced thrombocytopenia

■■ Hyperviscosity

Molecular

Predisposing risk factor score: ____

41377bdyfnl:41377 8/31/07 2:33 PM Page 38


REFERENCES

1. McIntyre, K. “Medicolegal implications of the consensusconference.” Chest.119(1 Suppl):337S-343S, Jan. 2001.

2. Geerts, W.H., Pineo, G.F., Heit, J.A., et al. “Preventionof venous thromboembolism: the Seventh ACCPConference on Antithrombotic and ThrombolyticTherapy.” Chest.126(3 suppl):338S-400S, Sept. 2004.

3. Caprini, J.A., Arcelus, J.I., Reyna, J.J. “Effective riskstratification of surgical and nonsurgical patients forvenous thromboembolic disease.” Semin Hematol.38(2 Suppl 5):12-19, April 2001.

4. Harlan, D. “The implications of practice guidelines for physician medical malpractice liability.” PhysicianExec.20(5):20-21, May 1994.

5. Anderson, F.A Jr., Wheeler, H.B., Goldberg, R.J., et al.“A population-based perspective of the hospital incidenceand case-fatality rates of deep vein thrombosis and pulmonary embolism.” The Worcester DVT Study.Arch Intern Med.151(5):933-938, May 1991.

6. Geerts, W.H., Heit, J.A., Clagett, G.P., et al. “Preventionof venous thromboembolism.” Chest.119(suppl1)(Suppl 1):132S-175S, Jan. 2001.

7. Cornwell, E.E. 3rd, Chang, D, Velmahos, G., et al.“Compliance with sequential compression device prophylaxis in at-risk trauma patients: a prospectiveanalysis.” Am Surg.68(5):470-473, May 2002.

8. Creswell, L.L., Schuessler, R.B., Rosenbloom, M., Cox, J.L. “Hazards of postoperative atrial arrhythmias.”Ann Thorac Surg.56(3):539-549, Sept. 1993.

9. Leitch, J.W., Thomson, D, Baird, D.K., Harris, P.J.“The importance of age as a predictor of atrial fibrillationand flutter after coronary artery bypass grafting.” J Thorac Cardiovasc Surg.100(3):338-342, Sept. 1990.

10. Hashimoto, K., Ilstrup, D.M., Schaff, H.V. “Influenceof clinical and hemodynamic variables on risk ofsupraventricular tachycardia after coronary artery bypass.”J Thorac Cardiovasc Surg.101(1):56-65, Jan. 1991.

11. Mathew, J.P., Parks, R., Savino, J.S., et al. “Atrial fib-rillation following coronary artery bypass graft surgery:predictors, outcomes and resource utilization.”MultiCenter Study of Perioperative Ischemia ResearchGroup. JAMA.276(4):300-306, July 24-31 1996.

12. Stamou, S.C., Hill, P.C., Dangas, G., et al. “Strokeafter coronary artery bypass: incidence, predictors andclinical outcome.” Stroke.32(7):1508-1513, July 2001.

13. Epstein, A.E., Alexander, J.C., Gutterman, D.D.,Maisel, W., Wharton, J.M. “Anticoagulation: AmericanCollege of Chest Physicians guidelines for the preventionand management of postoperative atrial fibrillation aftercardiac surgery.” Chest.128(2 Suppl):24S-27S, Aug. 2005.

14. Singer, D.E., Albers, G.W., Dalen, J.E., Go, A.S.,Halperin, J.L., Manning, W.J. “Antithrombotic therapyin atrial fibrillation: the Seventh ACCP Conference onAntithrombotic and Thrombolytic Therapy.”Chest.126(3 Suppl):429S-456S, Sept. 2004.

15. Steier, K.J., Singh, G., Ullah, A., Maneja, J., Ha, R.S.,Khan, F. “Venous thromboembolism: application andeffectiveness of the American College of Chest Physicians2001 guidelines for prophylaxis.” J Am OsteopathAssoc.106(7):388-395, July 2006.

16. Wheeler, A. “Venous thromboembolism in medicallyill patients: identifying risk and strategies for prevention.”Clin Cornerstone.7(4):23-31, 2005.

17. Snow, V., Qaseem, A., Barry, P., Hornbake, E.R.,Rodnick, J.E., Tobolic, T., Ireland, B., Segal, J.B., Bass,E.B., Weiss, K.N., Green, L., Owens, D.K., and theJoint American College of Physicians/AmericanAcademy of Family Physicians Panel on Deep VenousThrombosis/Pulmonary Embolism. “Management ofvenous thromboembolism: a clinical practice guidelinefrom the American College of Physicians and theAmerican Academy of Family Physicians.” Ann InternMed:146: 211-222. Feb. 2007.

ABOUT THE AUTHOR

Stanley A. Nasraway, MD, FCCM, is director, SurgicalIntensive Care Units, Tufts-New England Medical Centerand professor, Surgery, Medicine & Anesthesia, in Boston.

41377bdyfnl:41377 8/31/07 2:33 PM Page 39

avoiding pitfalls of anticoagulation therapy

Documents