Deep Venous Thrombosis and Venous Thromboembolism Prophylaxis Keely L. Buesing, MD*, Barghava Mullapudi, Kristin A. Flowers, MD
MD,
KEYWORDS Venous thromboembolism Deep venous thrombosis Risk factors Management strategies Prophylaxis KEY POINTS Venous thromboembolism (VTE) affects up to 25% of hospitalized patients, with up to 30% of those experiencing complications. Risk stratification is important in choosing therapy for prevention and management of VTE. Management of VTE depends on precipitating factors and future risk of VTE progression versus bleeding. Low-molecular-weight heparin is the preferred anticoagulant for initial treatment of VTE.
Venous thromboembolism (VTE), which includes deep venous thrombosis (DVT) and pulmonary embolism (PE), remains an all too familiar risk for surgical patients, occurring in up to 25% of those hospitalized.1 These patients are a unique population who possess all 3 components of Virchow triad (stasis, hypercoagulability, and endothelial injury), completing the triad known to be the cause of thrombus formation. Despite validated guidelines, the problem is frequently left inappropriately addressed, leaving patients at risk for a process that can lead to significant morbidity and mortality. Fifty percent of all DVTs are asymptomatic, but approximately 30% will have additional complications.2 For some patients, a DVT is a transient episode (ie, the symptoms resolve once the disease is successfully treated). For others, it can lead to a PE, which occurs in more than one-third of patients with DVT.1,2 PE causes sudden death in up to 34% of patients,3 particularly when one or more of the larger pulmonary arteries are completely blocked by clot. Most of those who survive do not have any lasting effects; however, if the embolus in the lung fails to completely dissolve, chronic pulmonary
Disclosure statement: The authors have nothing to disclose. Division of Trauma & Surgical Critical Care, Department of General Surgery, University of Nebraska Medical Center, 983280 Nebraska Medical Center, Omaha, NE 68198-3280, USA * Corresponding author. E-mail address: [email protected] Surg Clin N Am 95 (2015) 285–300 http://dx.doi.org/10.1016/j.suc.2014.11.005 surgical.theclinics.com 0039-6109/15/$ – see front matter Ó 2015 Elsevier Inc. All rights reserved.
286
Buesing et al
hypertension may eventually occur, causing chronic shortness of breath and varying degrees of heart failure. The Surgeon General’s First Call to Action to Prevent Deep Vein Thrombosis and Pulmonary Embolism came in 2008 and estimated 350,000 to 600,000 Americans each year have a DVT and/or PE. Furthermore, at least 100,000 deaths are attributed to DVT/PE each year.3 Of those who survive, many go on to have complications with serious and negative impacts on quality of life. DVT and PE are estimated to be the number one preventable cause of death in hospitalized patients. To offset this risk, the Surgical Care Improvement Project states in its guidelines that all surgical patients should have thromboprophylaxis ordered and administered within 24 hours of an operation. The Joint Commission also requires that all surgical patients receive anticoagulation, reflecting measures adopted by the Centers for Medicare and Medicaid Services, starting May 1st, 2009.4 Despite initiatives and mandates, VTE prophylaxis is underutilized in the United States. A 2009 analysis by Franklin Michota,5 citing data from a study by Brigham and Women’s Hospital in 2000, revealed that only 34% of high-risk patients receive appropriate prophylaxis. An article published in 2014 by the Journal of the American College of Surgeons about adopting mandatory VTE risk stratification and administration similarly revealed that only 58.5% of surgical patients at risk received VTE prophylaxis.4 Why? The reasons cited are as follows: 1. There is a fear of anticoagulant-associated bleeding. 2. There is a lack of awareness regarding VTE. 3. It is thought that guidelines are based on risks and benefits of prophylaxis in clinical trials that exclude recommendations for certain subsets of patients. 4. Individual risk assessment is necessary, making a protocol difficult to reinforce. The following sections are intended to address each of these cited reasons individually. BLEEDING RISK
The International Medical Prevention Registry on Venous Thromboembolism investigators developed a scoring system to calculate the risk of bleeding in medical patients.6 Table 1 shows the bleeding risk factors identified for purposes of this study. Scores greater than or equal to 7.0 were associated with a 7.9% risk of any bleeding and a 4.1% risk of major bleeding.6 If the risk of bleeding is greater than the risk of VTE, then chemical prophylaxis can be avoided. The ninth edition of the American College of Chest Physicians’ (ACCP) guidelines, revised and published in 2012, includes a consideration of the bleeding risk in patients receiving anticoagulants. They did not assess how the risk of bleeding would influence every recommendation because it would be unlikely to change the recommendation, there are few data assessing outcomes in patients with differing risks of bleeding, and because of the lack of validated tools for stratifying bleeding risk. For extendedduration anticoagulation, recommendations are based on 4 primary risk groups for VTE and 3 risk groups for major bleeding (Table 2). The estimated total of recurrent VTE versus major bleeding for each of the 12 combinations is shown in Table 3.7 LACK OF AWARENESS REGARDING VENOUS THROMBOEMBOLISM
Table 4 is a reproduction of the Venous Thromboembolism Update by Joseph Caprini, MD, and summarizes the incidence and percent of complications of VTE in an attempt to underscore the significance of VTE and associated complications.8
DVT and VTE Prophylaxis
Table 1 Factors at admission associated with bleeding risk Bleeding Risk Factors
Points
Moderate renal failure; GFR 30–59 vs >60 mL/min/m2
1
Male vs female
1
Age: 40–84 y vs 1.5)
2.5
Age: >85 y vs 2
2
Head AIS >2
2
Spinal fractures
3
Glasgow coma score 9 should receive LMWH primarily.
A-V foot pump
None
None
It can be used as a substitute in high-risk patients who cannot wear IPCDs.
IPCDs
None
None
It may have some benefit in isolated studies in traumatic brain injury.
IVC filters
None
None
It can be used in very high-risk patients who cannot receive anticoagulation.
Abbreviations: A-V, arteriovenous; LDH, low-density heparin; ISS, injury severity score; Recom, recommendations. Adapted from Rogers FB, Cipolle MD, Velmahos G, et al. Practice management guidelines for the prevention of venous thromboembolism in trauma patients: the EAST practice management guidelines work group. J Trauma 2002;53(1):142–64.
contraindication to LMWH, mechanical prophylaxis alone is recommended with either IPCDs or GCS. For major trauma patients with impaired mobility, the ACCP recommends VTE prophylaxis until the time of discharge. The ACCP does not recommend IVC filters as prophylaxis for patients with spinal cord injury; instead, they recommend LMWH or, alternatively, IPCDs with low-dose heparin or LMWH. If anticoagulant therapy is contraindicated, the use of IPCDs and/or compression stockings is recommended. The Eastern Association for the Surgery of Trauma (EAST) has developed evidencebased guidelines for VTE prophylaxis, last published in 2002. A summary of their recommendations can be found in Table 8.42 SUMMARY
The development of VTE remains a high risk in hospitalized surgical patients, leading to complications in up to 30%. The stratification of patient risk factors and subsequent utilization of a validated prophylaxis and treatment regimen is, therefore, of utmost importance. Familiarity with the current guidelines and recommendations ultimately results in decreased morbidity, mortality, and health care costs. REFERENCES
1. Silverstein MD, Heit JA, Mohr DN, et al. Trends in the incidence of deep vein thrombosis and pulmonary embolism: a 25-year population-based study. Arch Intern Med 1998;158(6):585–93. 2. Heit JA, Silverstein MD, Mohr DN, et al. Predictors of survival after deep vein thrombosis and pulmonary embolism: a population-based, cohort study. Arch Intern Med 1999;159(5):445–53.
297
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Buesing et al
3. Office of the Surgeon General (US), National Heart, Lung, and Blood Institute (US). The Surgeon General’s call to action to prevent deep vein thrombosis and pulmonary embolism. Rockville (MD): Office of the Surgeon General (US); 2008. References. Available at: http://www.ncbi.nlm.nih.gov/books/NBK44183/. 4. Cassidy M, Rosenkranz P, McAneny D. Reducing postoperative venous thromboembolism complications with a standardized risk-stratified prophylaxis protocol and mobilization program. J Am Coll Surg 2014;218(6):1095–104. 5. Michota FA. Bridging the gap between evidence and practice in venous thromboembolism prophylaxis: the quality improvement process. J Gen Intern Med 2007;22(12):1762–70. 6. Spyropouloos AC, Anderson FA Jr, Fitzgerald G, et al. Predictive and associative models to identify hospitalized medical patients at risk for VTE. Chest 2011; 139(1):69–79. 7. Kearon C, Akl EA, Comerota AJ, et al. Antithrombotic therapy and prevention of thrombosis, 9th ed: American College of Chest Physicians evidence-based clinical practice guidelines. Chest 2012;141(2 Suppl):e419S–94S. 8. Available at: http://web2.facs.org/download/Caprini.pdf. Accessed date June 24, 2014. 9. Prandoni P, Lensing AW, Cogo A, et al. The long-term clinical course of acute deep venous thrombosis. Ann Intern Med 1996;125(1):1–7. 10. Mohr DN, Silverstein MD, Heit JA, et al. The venous stasis syndrome after deep venous thrombosis or pulmonary embolism: a population-based study. Mayo Clin Proc 2000;75(12):1249–56. 11. Heit JA, Mohr DN, Silverstein MD, et al. Predictors of recurrence after deep vein thrombosis and pulmonary embolism: a population-based cohort study. Arch Intern Med 2000;160(6):761–8. 12. Caprini JA, Arcelus JI, Hasty JH, et al. Clinical assessment of venous thromboembolic risk in surgical patients. Semin Thromb Hemost 1991;17(Suppl 3): 304–12. 13. Bahl V, Hu H, Henke PK, et al. A validation study of a retrospective venous thromboembolism risk scoring method. Ann Surg 2010;251:344–5. 14. Caprini JA. Risk assessment as a guide for the prevention of the many faces of venous thromboembolism. Am J Surg 2010;199(Suppl):S3–10. 15. Gould MK, Garcia DA, Wren S, et al. Prevention of VTE in nonorthopedic surgical patients: antithrombotic therapy and prevention of thrombosis, 9th ed: American College of Chest Physicians evidence-based clinical practice guidelines. Chest 2012;141(2 Suppl):e227S–77S. 16. Shuman AG, Hu HM, Pannucci CJ, et al. Stratifying the risk of venous thromboembolism in otolaryngology. Otolaryngol Head Neck Surg 2012;146:719–24. 17. Torbicki A, Perrier A, Konstantinides S, et al. Guidelines on the diagnosis and management of acute pulmonary embolism: the task force for the diagnosis and management of acute pulmonary embolism of the European Society of Cardiology (ESC). Eur Heart J 2008;29:2276–315. 18. Streiff MB. Diagnosis and initial treatment of venous thromboembolism in patients with cancer. J Clin Oncol 2009;27:4889–94. 19. Perkins JM, Magee TR, Galland RB. Phlegmasia caerulea dolens and venous gangrene. Br J Surg 1996;83:19–23. 20. Tardy B, Moulin N, Mismetti P, et al. Intravenous thrombolytic therapy in patients with phlegmasia caerulea dolens. Haematologica 2006;91:281–2. 21. Tung CS, Soliman PT, Walace MJ, et al. Successful catheter-directed venous thrombolysis in phlegmasia cerulean dolens. Gynecol Oncol 2007;107:140–2.
DVT and VTE Prophylaxis
22. Einarsson E, Albrechtsson U, Eklof B. Thrombectomy and temporary AV-fistula in iliofemoral vein thrombosis. Technical considerations and early results. Int Angiol 1986;5:65–72. 23. Plate G, Einarsson E, Ohlin P, et al. Thrombectomy with temporary AV fistula: the treatment of choice in acute iliofemoral venous thrombosis. J Vasc Surg 1984;1: 867–76. 24. AbuRahma AF, Robinson PA. Effort subclavian vein thrombosis: evolution of management. J Endovasc Ther 2000;7:302–8. 25. De Bast Y, Dahin L. May-Thurner syndrome will be completed? Thromb Res 2009; 123:498–502. 26. Murphy EH, Davis EM, Journeycake JM, et al. Symptomatic iliofemoral DVT after onset of oral contraceptive use in women with previously undiagnosed MayThurner syndrome. J Vasc Surg 2009;49:697–703. 27. Knipp BS, Ferguson E, Williams DM, et al. Factors associated with outcome after interventional treatment of symptomatic iliac vein compression syndrome. J Vasc Surg 2007;46:743–9. 28. Comerota AJ. The ATTRACT trial: rationale for early intervention for iliofemoral DVT. Perspect Vasc Surg Endovasc Ther 2009;21:221–4 [quiz: 224–5]. 29. Enden T, Sandvik L, Klow NE, et al. Catheter-directed venous thrombolysis in acute iliofemoral vein thrombosis-the CaVenT study: rationale and design of a multicenter, randomized, controlled, clinical trial (NCT00251771). Am Heart J 2007;154:808–14. 30. Society of American Gastrointestinal and Endoscopic Surgeons (SAGES) Guidelines Committee. Guidelines for deep venous thrombosis prophylaxis during laparoscopic surgery. Surg Endosc 2007;21:1007–9. 31. Khorana AA, Dalal MR, Lin J, et al. Health care costs associated with venous thromboembolism in selected high-risk ambulatory patients with solid tumors undergoing chemotherapy in the United States. Clinicoecon Outcomes Res 2013;5:101–8. 32. Khorana AA, Dalal MR, Lin J, et al. Incidence and predictors of venous thromboembolism (VTE) among ambulatory high-risk cancer patients undergoing chemotherapy in the United States. Cancer 2013;119(3):648–55. 33. Lyman GH, Khorana AA, Kuderer NM, et al. Venous thromboembolism prophylaxis and treatment in patients with cancer: American Society of Clinical Oncology clinical practices update. J Clin Oncol 2013;31(17):2189–204. 34. Streiff MB, Bockenstedt PL, Cataland SR, et al. Venous thromboembolic disease. J Natl Compr Canc Netw 2013;11(11):1402–29. 35. Pryor HI 2nd, Singleton A, Lin E, et al. Practice patterns in high-risk bariatric venous thromboembolism prophylaxis. Surg Endosc 2013;27(3):843–8. 36. Falck-Ytter Y, Francis CW, Johanson NA, et al. Prevention of VTE in orthopedic surgery patients: antithrombotic therapy and prevention of thrombosis, 9th ed: American College of Chest Physicians evidence-based clinical practice guidelines. Chest 2012;141(2 Suppl):e278S–325S. 37. Bendinelli C, Balogh Z. Postinjury thromboprophylaxis. Curr Opin Crit Care 2008; 14(6):673–8. 38. Dunbar NM, Chandler WL. Thrombin generation in trauma patients. Transfusion 2009;49(12):2652–60. 39. Toker S, Hak DJ, Morgan SJ. Deep vein thrombosis prophylaxis in trauma patients. Thrombosis 2011;2011:505373. 40. Greenfield LJ, Proctor MC, Rodriguez JL, et al. Posttrauma thromboembolism prophylaxis. J Trauma 1997;42:100–3.
299
300
Buesing et al
41. Gearhart MM, Luchette FA, Proctor MC, et al. The risk assessment profile score identifies trauma patients at risk for deep vein thrombosis. Surgery 2000;128(4): 631–40. 42. Rogers FB, Cipolle MD, Velmahos G, et al. Practice management guidelines for the prevention of venous thromboembolism in trauma patients: the EAST practice management guidelines work group. J Trauma 2002;53(1):142–64.
MD,
KEYWORDS Venous thromboembolism Deep venous thrombosis Risk factors Management strategies Prophylaxis KEY POINTS Venous thromboembolism (VTE) affects up to 25% of hospitalized patients, with up to 30% of those experiencing complications. Risk stratification is important in choosing therapy for prevention and management of VTE. Management of VTE depends on precipitating factors and future risk of VTE progression versus bleeding. Low-molecular-weight heparin is the preferred anticoagulant for initial treatment of VTE.
Venous thromboembolism (VTE), which includes deep venous thrombosis (DVT) and pulmonary embolism (PE), remains an all too familiar risk for surgical patients, occurring in up to 25% of those hospitalized.1 These patients are a unique population who possess all 3 components of Virchow triad (stasis, hypercoagulability, and endothelial injury), completing the triad known to be the cause of thrombus formation. Despite validated guidelines, the problem is frequently left inappropriately addressed, leaving patients at risk for a process that can lead to significant morbidity and mortality. Fifty percent of all DVTs are asymptomatic, but approximately 30% will have additional complications.2 For some patients, a DVT is a transient episode (ie, the symptoms resolve once the disease is successfully treated). For others, it can lead to a PE, which occurs in more than one-third of patients with DVT.1,2 PE causes sudden death in up to 34% of patients,3 particularly when one or more of the larger pulmonary arteries are completely blocked by clot. Most of those who survive do not have any lasting effects; however, if the embolus in the lung fails to completely dissolve, chronic pulmonary
Disclosure statement: The authors have nothing to disclose. Division of Trauma & Surgical Critical Care, Department of General Surgery, University of Nebraska Medical Center, 983280 Nebraska Medical Center, Omaha, NE 68198-3280, USA * Corresponding author. E-mail address: [email protected] Surg Clin N Am 95 (2015) 285–300 http://dx.doi.org/10.1016/j.suc.2014.11.005 surgical.theclinics.com 0039-6109/15/$ – see front matter Ó 2015 Elsevier Inc. All rights reserved.
286
Buesing et al
hypertension may eventually occur, causing chronic shortness of breath and varying degrees of heart failure. The Surgeon General’s First Call to Action to Prevent Deep Vein Thrombosis and Pulmonary Embolism came in 2008 and estimated 350,000 to 600,000 Americans each year have a DVT and/or PE. Furthermore, at least 100,000 deaths are attributed to DVT/PE each year.3 Of those who survive, many go on to have complications with serious and negative impacts on quality of life. DVT and PE are estimated to be the number one preventable cause of death in hospitalized patients. To offset this risk, the Surgical Care Improvement Project states in its guidelines that all surgical patients should have thromboprophylaxis ordered and administered within 24 hours of an operation. The Joint Commission also requires that all surgical patients receive anticoagulation, reflecting measures adopted by the Centers for Medicare and Medicaid Services, starting May 1st, 2009.4 Despite initiatives and mandates, VTE prophylaxis is underutilized in the United States. A 2009 analysis by Franklin Michota,5 citing data from a study by Brigham and Women’s Hospital in 2000, revealed that only 34% of high-risk patients receive appropriate prophylaxis. An article published in 2014 by the Journal of the American College of Surgeons about adopting mandatory VTE risk stratification and administration similarly revealed that only 58.5% of surgical patients at risk received VTE prophylaxis.4 Why? The reasons cited are as follows: 1. There is a fear of anticoagulant-associated bleeding. 2. There is a lack of awareness regarding VTE. 3. It is thought that guidelines are based on risks and benefits of prophylaxis in clinical trials that exclude recommendations for certain subsets of patients. 4. Individual risk assessment is necessary, making a protocol difficult to reinforce. The following sections are intended to address each of these cited reasons individually. BLEEDING RISK
The International Medical Prevention Registry on Venous Thromboembolism investigators developed a scoring system to calculate the risk of bleeding in medical patients.6 Table 1 shows the bleeding risk factors identified for purposes of this study. Scores greater than or equal to 7.0 were associated with a 7.9% risk of any bleeding and a 4.1% risk of major bleeding.6 If the risk of bleeding is greater than the risk of VTE, then chemical prophylaxis can be avoided. The ninth edition of the American College of Chest Physicians’ (ACCP) guidelines, revised and published in 2012, includes a consideration of the bleeding risk in patients receiving anticoagulants. They did not assess how the risk of bleeding would influence every recommendation because it would be unlikely to change the recommendation, there are few data assessing outcomes in patients with differing risks of bleeding, and because of the lack of validated tools for stratifying bleeding risk. For extendedduration anticoagulation, recommendations are based on 4 primary risk groups for VTE and 3 risk groups for major bleeding (Table 2). The estimated total of recurrent VTE versus major bleeding for each of the 12 combinations is shown in Table 3.7 LACK OF AWARENESS REGARDING VENOUS THROMBOEMBOLISM
Table 4 is a reproduction of the Venous Thromboembolism Update by Joseph Caprini, MD, and summarizes the incidence and percent of complications of VTE in an attempt to underscore the significance of VTE and associated complications.8
DVT and VTE Prophylaxis
Table 1 Factors at admission associated with bleeding risk Bleeding Risk Factors
Points
Moderate renal failure; GFR 30–59 vs >60 mL/min/m2
1
Male vs female
1
Age: 40–84 y vs 1.5)
2.5
Age: >85 y vs 2
2
Head AIS >2
2
Spinal fractures
3
Glasgow coma score 9 should receive LMWH primarily.
A-V foot pump
None
None
It can be used as a substitute in high-risk patients who cannot wear IPCDs.
IPCDs
None
None
It may have some benefit in isolated studies in traumatic brain injury.
IVC filters
None
None
It can be used in very high-risk patients who cannot receive anticoagulation.
Abbreviations: A-V, arteriovenous; LDH, low-density heparin; ISS, injury severity score; Recom, recommendations. Adapted from Rogers FB, Cipolle MD, Velmahos G, et al. Practice management guidelines for the prevention of venous thromboembolism in trauma patients: the EAST practice management guidelines work group. J Trauma 2002;53(1):142–64.
contraindication to LMWH, mechanical prophylaxis alone is recommended with either IPCDs or GCS. For major trauma patients with impaired mobility, the ACCP recommends VTE prophylaxis until the time of discharge. The ACCP does not recommend IVC filters as prophylaxis for patients with spinal cord injury; instead, they recommend LMWH or, alternatively, IPCDs with low-dose heparin or LMWH. If anticoagulant therapy is contraindicated, the use of IPCDs and/or compression stockings is recommended. The Eastern Association for the Surgery of Trauma (EAST) has developed evidencebased guidelines for VTE prophylaxis, last published in 2002. A summary of their recommendations can be found in Table 8.42 SUMMARY
The development of VTE remains a high risk in hospitalized surgical patients, leading to complications in up to 30%. The stratification of patient risk factors and subsequent utilization of a validated prophylaxis and treatment regimen is, therefore, of utmost importance. Familiarity with the current guidelines and recommendations ultimately results in decreased morbidity, mortality, and health care costs. REFERENCES
1. Silverstein MD, Heit JA, Mohr DN, et al. Trends in the incidence of deep vein thrombosis and pulmonary embolism: a 25-year population-based study. Arch Intern Med 1998;158(6):585–93. 2. Heit JA, Silverstein MD, Mohr DN, et al. Predictors of survival after deep vein thrombosis and pulmonary embolism: a population-based, cohort study. Arch Intern Med 1999;159(5):445–53.
297
298
Buesing et al
3. Office of the Surgeon General (US), National Heart, Lung, and Blood Institute (US). The Surgeon General’s call to action to prevent deep vein thrombosis and pulmonary embolism. Rockville (MD): Office of the Surgeon General (US); 2008. References. Available at: http://www.ncbi.nlm.nih.gov/books/NBK44183/. 4. Cassidy M, Rosenkranz P, McAneny D. Reducing postoperative venous thromboembolism complications with a standardized risk-stratified prophylaxis protocol and mobilization program. J Am Coll Surg 2014;218(6):1095–104. 5. Michota FA. Bridging the gap between evidence and practice in venous thromboembolism prophylaxis: the quality improvement process. J Gen Intern Med 2007;22(12):1762–70. 6. Spyropouloos AC, Anderson FA Jr, Fitzgerald G, et al. Predictive and associative models to identify hospitalized medical patients at risk for VTE. Chest 2011; 139(1):69–79. 7. Kearon C, Akl EA, Comerota AJ, et al. Antithrombotic therapy and prevention of thrombosis, 9th ed: American College of Chest Physicians evidence-based clinical practice guidelines. Chest 2012;141(2 Suppl):e419S–94S. 8. Available at: http://web2.facs.org/download/Caprini.pdf. Accessed date June 24, 2014. 9. Prandoni P, Lensing AW, Cogo A, et al. The long-term clinical course of acute deep venous thrombosis. Ann Intern Med 1996;125(1):1–7. 10. Mohr DN, Silverstein MD, Heit JA, et al. The venous stasis syndrome after deep venous thrombosis or pulmonary embolism: a population-based study. Mayo Clin Proc 2000;75(12):1249–56. 11. Heit JA, Mohr DN, Silverstein MD, et al. Predictors of recurrence after deep vein thrombosis and pulmonary embolism: a population-based cohort study. Arch Intern Med 2000;160(6):761–8. 12. Caprini JA, Arcelus JI, Hasty JH, et al. Clinical assessment of venous thromboembolic risk in surgical patients. Semin Thromb Hemost 1991;17(Suppl 3): 304–12. 13. Bahl V, Hu H, Henke PK, et al. A validation study of a retrospective venous thromboembolism risk scoring method. Ann Surg 2010;251:344–5. 14. Caprini JA. Risk assessment as a guide for the prevention of the many faces of venous thromboembolism. Am J Surg 2010;199(Suppl):S3–10. 15. Gould MK, Garcia DA, Wren S, et al. Prevention of VTE in nonorthopedic surgical patients: antithrombotic therapy and prevention of thrombosis, 9th ed: American College of Chest Physicians evidence-based clinical practice guidelines. Chest 2012;141(2 Suppl):e227S–77S. 16. Shuman AG, Hu HM, Pannucci CJ, et al. Stratifying the risk of venous thromboembolism in otolaryngology. Otolaryngol Head Neck Surg 2012;146:719–24. 17. Torbicki A, Perrier A, Konstantinides S, et al. Guidelines on the diagnosis and management of acute pulmonary embolism: the task force for the diagnosis and management of acute pulmonary embolism of the European Society of Cardiology (ESC). Eur Heart J 2008;29:2276–315. 18. Streiff MB. Diagnosis and initial treatment of venous thromboembolism in patients with cancer. J Clin Oncol 2009;27:4889–94. 19. Perkins JM, Magee TR, Galland RB. Phlegmasia caerulea dolens and venous gangrene. Br J Surg 1996;83:19–23. 20. Tardy B, Moulin N, Mismetti P, et al. Intravenous thrombolytic therapy in patients with phlegmasia caerulea dolens. Haematologica 2006;91:281–2. 21. Tung CS, Soliman PT, Walace MJ, et al. Successful catheter-directed venous thrombolysis in phlegmasia cerulean dolens. Gynecol Oncol 2007;107:140–2.
DVT and VTE Prophylaxis
22. Einarsson E, Albrechtsson U, Eklof B. Thrombectomy and temporary AV-fistula in iliofemoral vein thrombosis. Technical considerations and early results. Int Angiol 1986;5:65–72. 23. Plate G, Einarsson E, Ohlin P, et al. Thrombectomy with temporary AV fistula: the treatment of choice in acute iliofemoral venous thrombosis. J Vasc Surg 1984;1: 867–76. 24. AbuRahma AF, Robinson PA. Effort subclavian vein thrombosis: evolution of management. J Endovasc Ther 2000;7:302–8. 25. De Bast Y, Dahin L. May-Thurner syndrome will be completed? Thromb Res 2009; 123:498–502. 26. Murphy EH, Davis EM, Journeycake JM, et al. Symptomatic iliofemoral DVT after onset of oral contraceptive use in women with previously undiagnosed MayThurner syndrome. J Vasc Surg 2009;49:697–703. 27. Knipp BS, Ferguson E, Williams DM, et al. Factors associated with outcome after interventional treatment of symptomatic iliac vein compression syndrome. J Vasc Surg 2007;46:743–9. 28. Comerota AJ. The ATTRACT trial: rationale for early intervention for iliofemoral DVT. Perspect Vasc Surg Endovasc Ther 2009;21:221–4 [quiz: 224–5]. 29. Enden T, Sandvik L, Klow NE, et al. Catheter-directed venous thrombolysis in acute iliofemoral vein thrombosis-the CaVenT study: rationale and design of a multicenter, randomized, controlled, clinical trial (NCT00251771). Am Heart J 2007;154:808–14. 30. Society of American Gastrointestinal and Endoscopic Surgeons (SAGES) Guidelines Committee. Guidelines for deep venous thrombosis prophylaxis during laparoscopic surgery. Surg Endosc 2007;21:1007–9. 31. Khorana AA, Dalal MR, Lin J, et al. Health care costs associated with venous thromboembolism in selected high-risk ambulatory patients with solid tumors undergoing chemotherapy in the United States. Clinicoecon Outcomes Res 2013;5:101–8. 32. Khorana AA, Dalal MR, Lin J, et al. Incidence and predictors of venous thromboembolism (VTE) among ambulatory high-risk cancer patients undergoing chemotherapy in the United States. Cancer 2013;119(3):648–55. 33. Lyman GH, Khorana AA, Kuderer NM, et al. Venous thromboembolism prophylaxis and treatment in patients with cancer: American Society of Clinical Oncology clinical practices update. J Clin Oncol 2013;31(17):2189–204. 34. Streiff MB, Bockenstedt PL, Cataland SR, et al. Venous thromboembolic disease. J Natl Compr Canc Netw 2013;11(11):1402–29. 35. Pryor HI 2nd, Singleton A, Lin E, et al. Practice patterns in high-risk bariatric venous thromboembolism prophylaxis. Surg Endosc 2013;27(3):843–8. 36. Falck-Ytter Y, Francis CW, Johanson NA, et al. Prevention of VTE in orthopedic surgery patients: antithrombotic therapy and prevention of thrombosis, 9th ed: American College of Chest Physicians evidence-based clinical practice guidelines. Chest 2012;141(2 Suppl):e278S–325S. 37. Bendinelli C, Balogh Z. Postinjury thromboprophylaxis. Curr Opin Crit Care 2008; 14(6):673–8. 38. Dunbar NM, Chandler WL. Thrombin generation in trauma patients. Transfusion 2009;49(12):2652–60. 39. Toker S, Hak DJ, Morgan SJ. Deep vein thrombosis prophylaxis in trauma patients. Thrombosis 2011;2011:505373. 40. Greenfield LJ, Proctor MC, Rodriguez JL, et al. Posttrauma thromboembolism prophylaxis. J Trauma 1997;42:100–3.
299
300
Buesing et al
41. Gearhart MM, Luchette FA, Proctor MC, et al. The risk assessment profile score identifies trauma patients at risk for deep vein thrombosis. Surgery 2000;128(4): 631–40. 42. Rogers FB, Cipolle MD, Velmahos G, et al. Practice management guidelines for the prevention of venous thromboembolism in trauma patients: the EAST practice management guidelines work group. J Trauma 2002;53(1):142–64.
