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Current practice of thromboprophylaxis in the burn population: A survey study of 84 US burn centers
Burns 31 (2005) 964–966 www.elsevier.com/locate/burns
Current practice of thromboprophylaxis in the burn population: A survey study of 84 US burn centers Robert E.H. Ferguson b,*, Agatha Critchfield b, Aimee LeClaire a, Nicolas Ajkay b, Henry C. Vasconez b b
a University of Kentucky College of Pharmacy, Lexington, KY, USA Division of Plastic Surgery, University of Kentucky College of Medicine, Lexington, KY, USA
Accepted 22 June 2005
Abstract While there is limited prospective data on the incidence of venous thromboembolism (VTE) in the burn population, there are no prospective studies on the efficacy and safety of VTE prophylaxis in these patients. Despite lack of such data, we hypothesized that most burn centers practice some form of prophylaxis. Eighty-four US burn centers were contacted regarding their modality of VTE prophylaxis, if any. Of the 84 US burn centers, 71 were enrolled in this survey. 76.1% centers reported routine VTE prophylaxis. Modalities included sequential compression device (SCD) (33), subcutaneous heparin (31), enoxaparin (13), dalteparin (3), and intravenous heparin infusion (1). Twenty-one reported combined modalities of SCD and subcutaneous heparin (19), SCD and enoxaparin (1), or SCD and dalteparin (1). Survey results underscore the need to definitively establish risk factors for VTE in the burn population and to prospectively define an evidence-based standard of care in prophylaxis for those patients. # 2005 Elsevier Ltd and ISBI. All rights reserved. Keywords: Thromboprophylaxis; Burn population; US burn centers
1. Introduction The complication of venous thromboembolism (VTE) is well documented in patients hospitalized for major trauma [1–4] or acute medical illnesses [5,6]. While historically the risk of VTE was considered to be low in patients hospitalized for thermal injury [7,8], autopsy reports [9,10], and more recent prospective studies suggest that the risk of VTE in the burn population is more substantial than previously considered [11–13]. Extensive data supports the clinical benefit and costeffectiveness of routine thromboprophylaxis in the trauma [14,15], surgical [16–20], and medical populations [21]. Similar data do not exist for the burn population [11,16]. We hypothesized that the majority of burn centers implement
* Corresponding author. Present address: Division of Plastic Surgery, K454 KY Clinic, 740 South Limestone, University of Kentucky Chandler Medical Center, Lexington, KY 40536, USA. Tel.: +1 859 257 8344. E-mail address: [email protected] (Robert E.H. Ferguson). 0305-4179/$30.00 # 2005 Elsevier Ltd and ISBI. All rights reserved. doi:10.1016/j.burns.2005.06.011
some modality of VTE prophylaxis despite the lack of prospective data in the burn population. This prompted our survey of burn centers across the United States (US) to discover if routine thromboprophylaxis is implemented and, if so, by which modality. 2. Methods Between December 2003 and February 2004, 84 US burn centers were contacted by telephone using a listing of adult burn centers available to the public on the American Burn Association website (www.ameriburn.org) and the Burn Survivor Resource Center (www.burnsurvivor.com). These calls were made between 8:00 a.m. and 5:00 p.m. according to the time zone in which the hospital being surveyed was located. Study inclusion criteria included hospitals with a dedicated burn unit, an adult burn population, and a nurse available for participation who has worked at least three years in that unit. Centers were excluded from the study if the interviewee declined to participate in the survey or if
R.E.H. Ferguson et al. / Burns 31 (2005) 964–966
there was no answer in the burn unit after three separate attempts. Requests to call at a later time were honored. For cases in which the listed phone number was incorrect, the burn unit was reached through hospital information. Once an individual answered the burn unit phone, the survey investigator made an introduction and asked to speak to a burn nurse who has worked at that facility for at least three years. At this point, a survey script approved by our Institutional Review Board was used by the investigator to conduct the study. Each nurse participant understood that they would need to be available for approximately 3 min without neglecting patient care. Confidentiality risks were described as negligible because participants’ names would not be used and their answers were not to be identified in relation to the facility name. After an explanation that they could terminate participation in the survey at any time, the following questions were asked: 1. How many years have you worked with burn patients as a nurse? 2. How many years have you worked with burn patients at this burn center? 3. Does your center routinely practice VTE prophylaxis for burn patients? 4. If yes, what VTE prophylaxis is used? 5. How many beds are in your unit? 6. How many of those beds are currently occupied by burn patients? Answers to these questions were recorded as they were given.
3. Results Of the 84 US burn centers that were called, 71 centers were enrolled in the survey. Nine centers did not wish to participate and four centers did not answer their telephone. No participant prematurely terminated the interview after agreeing to participate. All 10 US geographic regions were represented in this study. The average number of beds at the participating burn centers was 11 (range 3–25 beds) with an average of 7.62 beds occupied by burns at the time of the survey (range 0–24 beds). Of the nurses surveyed, the average number of years of experience working with burn patients was 11.82 (range 3–29 years), and the average number of years that the participating nurses had worked at their respective burn center was 11.35 (range 3–28 years). Table 1 Does your center routinely practice venous thromboembolism prophylaxis in burn patients? Answer
No. of centers (%)
Yes No
54 (76.1%) 17 (23.9%)
965
Table 2 Modalities of venous thromboembolism prophylaxis reported Modality a
SCD Heparin SQa Nothing Enoxaparin Dalteparin Heparin gtta
No. of centers 33 31 17 13 3 1
a
SCD: sequential compression device; heparin SQ: subcutaneous heparin; heparin gtt: intravenous heparin infusion.
Seventeen (23.9%) of the participants reported that their center does not routinely provide VTE prophylaxis, while 54 (76.1%) stated that they did (Table 1). The average number of beds was 9.6 at the former centers and 11.4 in the latter centers. Of those who provide thromboprophylaxis, the modalities reported (along with number reporting the modality) were sequential compression device (SCD) (33), subcutaneous heparin (31), enoxaparin (13), dalteparin (3), and intravenous heparin infusion (1) (Table 2). Of note, 21 reported combined modalities of SCD and subcutaneous heparin (19), SCD and enoxaparin (1), or SCD and dalteparin (1).
4. Discussion Venous thromboembolism is a relatively common complication in patients who have been hospitalized for major trauma [1–4] or acute medical illness [5,6]. Extensive data supports the clinical benefit and cost-effectiveness of routine thromboprophylaxis with low-molecular weight heparin in the trauma [14,15], surgical [16–20], and medical populations [21]. There seems to be continued questions regarding the significance of thromboembolism in the thermally injured patient. While most burn patients fulfill Virchow’s triad of venous thrombosis (stasis, local injury, and hypercoagulability), retrospective analyses have reported incidences as low as 0.9 and 0.4% for symptomatic deep vein thrombosis (DVT) and symptomatic pulmonary embolism (PE) respectively in the burn population [7,8]. Autopsy reports of burn deaths, however, reveal an incidence of PE as high as 30% [9,10]. In addition, preliminary results of a prospective screening study of the burn population reports a 23% incidence of DVT [11]. While the true frequency of venous thromboembolism in thermally injured patients is not known, prospective studies and recent reports suggest that they are at significant risk [11–13,22]. Evidence of the efficacy of routine thromboprophylaxis in the thermally injured patient does not exist as it has never been studied in a prospective, randomized fashion [11,16]. Despite the lack of data with regard to routine thromboprophylaxis in the burn population, 76% of the burn units surveyed practice some form of prophylaxis.
966
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However, approximately 24% of the burn centers surveyed do nothing at all. This suggests it may be concluded that either the data regarding VTE in the burn population has not adequately answered the question of its clinical significance or the effectiveness and safety of routine thromboprophylaxis in the burn population has not been generally accepted. In addition, the variability in modalities among those who do routinely provide thromboprophylaxis is further evidence to the lack of an evidence-based standard in this area of burn care. As prospective studies continue, it is anticipated that definite risk factors for thromboembolic events in the burn population will be established. In addition, a prospective, randomized study comparing modalities of thromboprophylaxis will be necessary to ascertain which method will be the safest and most effective in the thermally injured patient.
Conflict of interest statement The authors of this survey study have no conflicts of interest to report.
References [1] Rogers FB. Venous thromboembolism in trauma patients. Surg Clin North Am 1995;75:279–91. [2] Geerts WH, Code KI, Jay RM, Chen E, Szalai JP. A prospective study of venous thromboembolism after major trauma. N Engl J Med 1994;331:1601–6. [3] O’Malley KF, Ross SE. Pulmonary embolism in major trauma patients. J Trauma 1990;30:748–50. [4] Shackford SR, Davis JW, Hollingworth-Fridlund P, Brewer NS, Hoyt DB, Mackersie RC. Venous thromboembolism in patients with major trauma. Am J Surg 1990;159:365–9. [5] Lindblad B, Sternby NH, Bergqvist D. Incidence of venous thromboembolism verified by necropsy over 30 years. BMJ 1991;302:709– 11. [6] Sandler DA, Martin JF. Autopsy proven pulmonary embolism in hospital patients: are we detecting enough deep vein thrombosis. J R Soc Med 1989;82:203–5.
[7] Rue LW, Cioffi WG, Rush R, McManus WF, Pruitt BA. Thromboembolic complications in thermally injured patients. World J Surg 1992;16:1151–5. [8] Purdue GF, Hunt JL. Pulmonary emboli in burned patients. J Trauma 1988;28:218–20. [9] Warden GD, Wilmore DW, Pruitt BA. Central venous thrombosis: a hazard of medical progress. J Trauma 1973;13:620–6. [10] Sevitt S, Gallagher N. Venous thrombosis and pulmonary embolism; a clinico-pathological study in injured and burned patients. Br J Surg 1961;48:475–88. [11] Wahl WL, Brandt MM, Ahrns KS, et al. Venous thrombosis incidence in burn patients: preliminary results of a prospective study. J Burn Care Rehabil 2002;23:97–102. [12] Harrington DT, Mozingo DW, Cancio L, Bird P, Jordan B, Goodwin CW. Thermally injured patients are at significant risk for thromboembolic complications. J Trauma 2001;50:495–9. [13] Wahl WL, Brandt MM, Ahrns K, Corpron CA, Franklin GA. The utility of D-dimer levels in screening for thromboemobolic complications in burn patients. J Burn Care Rehabil 2002;23: 439–43. [14] Geerts WH, Jay RM, Code KI, et al. A comparison of low-dose heparin with low-molecular weight heparin as prophylaxis against venous thromboembolism after major trauma. N Engl J Med 1996;335:701– 17. [15] Schwarcz TH, Quick RC, Minion DJ, Kearney PA, Kwolek CJ, Endean ED. Enoxaparin treatment in high-risk trauma patients limits the utility of surveillance venous duplex scanning. J Vasc Surg 2001;34:447–52. [16] Geerts WH, Heit JA, Clagett GP, et al. Prevention of venous thromboembolism. Chest 2001;119:132S–75S. [17] Prevention of venous thromboembolism: international consensus statement (guidelines according to scientific evidence). Int Angiol 1997;16:3–38. [18] Leizorovicz A, Haugh MC, Chapuis FR, Samama MM, Boissel JP. Low molecular weight heparin in prevention of perioperative thrombosis. BMJ 1992;305:913–20. [19] Oster G, Tuden RL, Colditz GA. Prevention of venous thromboembolism after general surgery: cost-effectiveness analysis of alternative approaches to prophylaxis. Am J Med 1987;82:889–99. [20] Bergqvist D, Matzsch T, Jendteg S, Lindgren B, Persson U. The costeffectiveness of prevention of post-operative thromboembolism. Act Chir Scand Suppl 1990;556:36–41. [21] Samama MM, Cohen AT, Darmon JY, et al. A comparison of enoxaparin with placebo for the prevention of venous thromboembolism in acutely ill medical patients. N Engl J Med 1999;341:793–800. [22] Mayou B, Wee J, Girling M. Deep vein thrombosis. Burns 1980;7:438–40.
Current practice of thromboprophylaxis in the burn population: A survey study of 84 US burn centers Robert E.H. Ferguson b,*, Agatha Critchfield b, Aimee LeClaire a, Nicolas Ajkay b, Henry C. Vasconez b b
a University of Kentucky College of Pharmacy, Lexington, KY, USA Division of Plastic Surgery, University of Kentucky College of Medicine, Lexington, KY, USA
Accepted 22 June 2005
Abstract While there is limited prospective data on the incidence of venous thromboembolism (VTE) in the burn population, there are no prospective studies on the efficacy and safety of VTE prophylaxis in these patients. Despite lack of such data, we hypothesized that most burn centers practice some form of prophylaxis. Eighty-four US burn centers were contacted regarding their modality of VTE prophylaxis, if any. Of the 84 US burn centers, 71 were enrolled in this survey. 76.1% centers reported routine VTE prophylaxis. Modalities included sequential compression device (SCD) (33), subcutaneous heparin (31), enoxaparin (13), dalteparin (3), and intravenous heparin infusion (1). Twenty-one reported combined modalities of SCD and subcutaneous heparin (19), SCD and enoxaparin (1), or SCD and dalteparin (1). Survey results underscore the need to definitively establish risk factors for VTE in the burn population and to prospectively define an evidence-based standard of care in prophylaxis for those patients. # 2005 Elsevier Ltd and ISBI. All rights reserved. Keywords: Thromboprophylaxis; Burn population; US burn centers
1. Introduction The complication of venous thromboembolism (VTE) is well documented in patients hospitalized for major trauma [1–4] or acute medical illnesses [5,6]. While historically the risk of VTE was considered to be low in patients hospitalized for thermal injury [7,8], autopsy reports [9,10], and more recent prospective studies suggest that the risk of VTE in the burn population is more substantial than previously considered [11–13]. Extensive data supports the clinical benefit and costeffectiveness of routine thromboprophylaxis in the trauma [14,15], surgical [16–20], and medical populations [21]. Similar data do not exist for the burn population [11,16]. We hypothesized that the majority of burn centers implement
* Corresponding author. Present address: Division of Plastic Surgery, K454 KY Clinic, 740 South Limestone, University of Kentucky Chandler Medical Center, Lexington, KY 40536, USA. Tel.: +1 859 257 8344. E-mail address: [email protected] (Robert E.H. Ferguson). 0305-4179/$30.00 # 2005 Elsevier Ltd and ISBI. All rights reserved. doi:10.1016/j.burns.2005.06.011
some modality of VTE prophylaxis despite the lack of prospective data in the burn population. This prompted our survey of burn centers across the United States (US) to discover if routine thromboprophylaxis is implemented and, if so, by which modality. 2. Methods Between December 2003 and February 2004, 84 US burn centers were contacted by telephone using a listing of adult burn centers available to the public on the American Burn Association website (www.ameriburn.org) and the Burn Survivor Resource Center (www.burnsurvivor.com). These calls were made between 8:00 a.m. and 5:00 p.m. according to the time zone in which the hospital being surveyed was located. Study inclusion criteria included hospitals with a dedicated burn unit, an adult burn population, and a nurse available for participation who has worked at least three years in that unit. Centers were excluded from the study if the interviewee declined to participate in the survey or if
R.E.H. Ferguson et al. / Burns 31 (2005) 964–966
there was no answer in the burn unit after three separate attempts. Requests to call at a later time were honored. For cases in which the listed phone number was incorrect, the burn unit was reached through hospital information. Once an individual answered the burn unit phone, the survey investigator made an introduction and asked to speak to a burn nurse who has worked at that facility for at least three years. At this point, a survey script approved by our Institutional Review Board was used by the investigator to conduct the study. Each nurse participant understood that they would need to be available for approximately 3 min without neglecting patient care. Confidentiality risks were described as negligible because participants’ names would not be used and their answers were not to be identified in relation to the facility name. After an explanation that they could terminate participation in the survey at any time, the following questions were asked: 1. How many years have you worked with burn patients as a nurse? 2. How many years have you worked with burn patients at this burn center? 3. Does your center routinely practice VTE prophylaxis for burn patients? 4. If yes, what VTE prophylaxis is used? 5. How many beds are in your unit? 6. How many of those beds are currently occupied by burn patients? Answers to these questions were recorded as they were given.
3. Results Of the 84 US burn centers that were called, 71 centers were enrolled in the survey. Nine centers did not wish to participate and four centers did not answer their telephone. No participant prematurely terminated the interview after agreeing to participate. All 10 US geographic regions were represented in this study. The average number of beds at the participating burn centers was 11 (range 3–25 beds) with an average of 7.62 beds occupied by burns at the time of the survey (range 0–24 beds). Of the nurses surveyed, the average number of years of experience working with burn patients was 11.82 (range 3–29 years), and the average number of years that the participating nurses had worked at their respective burn center was 11.35 (range 3–28 years). Table 1 Does your center routinely practice venous thromboembolism prophylaxis in burn patients? Answer
No. of centers (%)
Yes No
54 (76.1%) 17 (23.9%)
965
Table 2 Modalities of venous thromboembolism prophylaxis reported Modality a
SCD Heparin SQa Nothing Enoxaparin Dalteparin Heparin gtta
No. of centers 33 31 17 13 3 1
a
SCD: sequential compression device; heparin SQ: subcutaneous heparin; heparin gtt: intravenous heparin infusion.
Seventeen (23.9%) of the participants reported that their center does not routinely provide VTE prophylaxis, while 54 (76.1%) stated that they did (Table 1). The average number of beds was 9.6 at the former centers and 11.4 in the latter centers. Of those who provide thromboprophylaxis, the modalities reported (along with number reporting the modality) were sequential compression device (SCD) (33), subcutaneous heparin (31), enoxaparin (13), dalteparin (3), and intravenous heparin infusion (1) (Table 2). Of note, 21 reported combined modalities of SCD and subcutaneous heparin (19), SCD and enoxaparin (1), or SCD and dalteparin (1).
4. Discussion Venous thromboembolism is a relatively common complication in patients who have been hospitalized for major trauma [1–4] or acute medical illness [5,6]. Extensive data supports the clinical benefit and cost-effectiveness of routine thromboprophylaxis with low-molecular weight heparin in the trauma [14,15], surgical [16–20], and medical populations [21]. There seems to be continued questions regarding the significance of thromboembolism in the thermally injured patient. While most burn patients fulfill Virchow’s triad of venous thrombosis (stasis, local injury, and hypercoagulability), retrospective analyses have reported incidences as low as 0.9 and 0.4% for symptomatic deep vein thrombosis (DVT) and symptomatic pulmonary embolism (PE) respectively in the burn population [7,8]. Autopsy reports of burn deaths, however, reveal an incidence of PE as high as 30% [9,10]. In addition, preliminary results of a prospective screening study of the burn population reports a 23% incidence of DVT [11]. While the true frequency of venous thromboembolism in thermally injured patients is not known, prospective studies and recent reports suggest that they are at significant risk [11–13,22]. Evidence of the efficacy of routine thromboprophylaxis in the thermally injured patient does not exist as it has never been studied in a prospective, randomized fashion [11,16]. Despite the lack of data with regard to routine thromboprophylaxis in the burn population, 76% of the burn units surveyed practice some form of prophylaxis.
966
R.E.H. Ferguson et al. / Burns 31 (2005) 964–966
However, approximately 24% of the burn centers surveyed do nothing at all. This suggests it may be concluded that either the data regarding VTE in the burn population has not adequately answered the question of its clinical significance or the effectiveness and safety of routine thromboprophylaxis in the burn population has not been generally accepted. In addition, the variability in modalities among those who do routinely provide thromboprophylaxis is further evidence to the lack of an evidence-based standard in this area of burn care. As prospective studies continue, it is anticipated that definite risk factors for thromboembolic events in the burn population will be established. In addition, a prospective, randomized study comparing modalities of thromboprophylaxis will be necessary to ascertain which method will be the safest and most effective in the thermally injured patient.
Conflict of interest statement The authors of this survey study have no conflicts of interest to report.
References [1] Rogers FB. Venous thromboembolism in trauma patients. Surg Clin North Am 1995;75:279–91. [2] Geerts WH, Code KI, Jay RM, Chen E, Szalai JP. A prospective study of venous thromboembolism after major trauma. N Engl J Med 1994;331:1601–6. [3] O’Malley KF, Ross SE. Pulmonary embolism in major trauma patients. J Trauma 1990;30:748–50. [4] Shackford SR, Davis JW, Hollingworth-Fridlund P, Brewer NS, Hoyt DB, Mackersie RC. Venous thromboembolism in patients with major trauma. Am J Surg 1990;159:365–9. [5] Lindblad B, Sternby NH, Bergqvist D. Incidence of venous thromboembolism verified by necropsy over 30 years. BMJ 1991;302:709– 11. [6] Sandler DA, Martin JF. Autopsy proven pulmonary embolism in hospital patients: are we detecting enough deep vein thrombosis. J R Soc Med 1989;82:203–5.
[7] Rue LW, Cioffi WG, Rush R, McManus WF, Pruitt BA. Thromboembolic complications in thermally injured patients. World J Surg 1992;16:1151–5. [8] Purdue GF, Hunt JL. Pulmonary emboli in burned patients. J Trauma 1988;28:218–20. [9] Warden GD, Wilmore DW, Pruitt BA. Central venous thrombosis: a hazard of medical progress. J Trauma 1973;13:620–6. [10] Sevitt S, Gallagher N. Venous thrombosis and pulmonary embolism; a clinico-pathological study in injured and burned patients. Br J Surg 1961;48:475–88. [11] Wahl WL, Brandt MM, Ahrns KS, et al. Venous thrombosis incidence in burn patients: preliminary results of a prospective study. J Burn Care Rehabil 2002;23:97–102. [12] Harrington DT, Mozingo DW, Cancio L, Bird P, Jordan B, Goodwin CW. Thermally injured patients are at significant risk for thromboembolic complications. J Trauma 2001;50:495–9. [13] Wahl WL, Brandt MM, Ahrns K, Corpron CA, Franklin GA. The utility of D-dimer levels in screening for thromboemobolic complications in burn patients. J Burn Care Rehabil 2002;23: 439–43. [14] Geerts WH, Jay RM, Code KI, et al. A comparison of low-dose heparin with low-molecular weight heparin as prophylaxis against venous thromboembolism after major trauma. N Engl J Med 1996;335:701– 17. [15] Schwarcz TH, Quick RC, Minion DJ, Kearney PA, Kwolek CJ, Endean ED. Enoxaparin treatment in high-risk trauma patients limits the utility of surveillance venous duplex scanning. J Vasc Surg 2001;34:447–52. [16] Geerts WH, Heit JA, Clagett GP, et al. Prevention of venous thromboembolism. Chest 2001;119:132S–75S. [17] Prevention of venous thromboembolism: international consensus statement (guidelines according to scientific evidence). Int Angiol 1997;16:3–38. [18] Leizorovicz A, Haugh MC, Chapuis FR, Samama MM, Boissel JP. Low molecular weight heparin in prevention of perioperative thrombosis. BMJ 1992;305:913–20. [19] Oster G, Tuden RL, Colditz GA. Prevention of venous thromboembolism after general surgery: cost-effectiveness analysis of alternative approaches to prophylaxis. Am J Med 1987;82:889–99. [20] Bergqvist D, Matzsch T, Jendteg S, Lindgren B, Persson U. The costeffectiveness of prevention of post-operative thromboembolism. Act Chir Scand Suppl 1990;556:36–41. [21] Samama MM, Cohen AT, Darmon JY, et al. A comparison of enoxaparin with placebo for the prevention of venous thromboembolism in acutely ill medical patients. N Engl J Med 1999;341:793–800. [22] Mayou B, Wee J, Girling M. Deep vein thrombosis. Burns 1980;7:438–40.