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Economic Impact of Tranexamic Acid in Healthy Patients Undergoing Primary Total Hip and Knee Arthroplasty
The Journal of Arthroplasty 28 Suppl. 1 (2013) 137–139
Contents lists available at ScienceDirect
The Journal of Arthroplasty journal homepage: www.arthroplastyjournal.org
Economic Impact of Tranexamic Acid in Healthy Patients Undergoing Primary Total Hip and Knee Arthroplasty Blake P. Gillette, MD, Hilal Maradit Kremers, MD, MSc, Christopher M. Duncan, MD, Hugh M. Smith, PhD, Robert T. Trousdale, MD, Mark W. Pagnano, MD, Rafael J. Sierra, MD a r t i c l e
i n f o
Article history: Received 17 August 2012 Accepted 7 April 2013 Keywords: tranexamic acid economic impact hip and knee arthroplasty
a b s t r a c t Tranexamic acid (TA) has been shown to reduce perioperative blood loss and blood transfusion. While concern remains about the cost of antifibrinolytic medication, we hypothesized that routine use of tranexamic acid would result in lower direct hospital total cost by decreasing costs associated with blood transfusion, laboratory testing, and room & board. Patients with an American Society of Anesthesiologists (ASA) class II or less undergoing primary total hip or knee arthroplasty at a single institution during 2007–2008 were retrospectively reviewed. The estimated mean direct hospital total cost, operating room, blood/lab, room & board, and pharmacy costs were compared between patients who did and did not receive TA. The study population included 1018 patients, and 580 patients received TA. The mean direct total cost of hospitalization with and without TA was $15,099 and $15,978 (P b .0002) respectively, a difference of $879. The only increased cost associated with TA was the pharmacy cost which was $921 versus $781 (P b .0001). The routine use of tranexamic acid TA was associated with lower mean direct hospital total costs after primary total hip and knee arthroplasty as the increase in pharmacy costs was more than offset by cost savings in other categories. © 2013 Elsevier Inc. All rights reserved.
Antifibrinolytic medications, such as tranexamic acid (TA), have emerged as effective perioperative blood-preserving agents in total joint arthroplasty. TA is a lysine analogue that inhibits clot degradation by preventing plasmin from binding to newly formed clots [1,2]. Both retrospective and prospective studies, as well as subsequent meta-analyses, have shown that TA reduces perioperative blood loss and transfusion rates without an increased risk of venous thromboembolism [3–15]. However, with increasing total hip arthroplasty (THA) and total knee arthroplasty (TKA) volumes [16], escalating costs, and recent emphasis on cost-containment strategies, the economic impact of TA is an important consideration in modern orthopedic surgery. Blood transfusion during total joint arthroplasty is an expensive intervention costing approximately $1000 in addition to the potentially deleterious effects of immune suppression, wound infection, transfusion reaction, and fluid overload [17–20]. Minimizing patient exposure to blood transfusions, while maintaining higher postoperative hemoglobin levels, is beneficial from a patient care standpoint and may lead to faster recovery and shorter hospital stay. Reducing perioperative transfusions may also lead to reductions in laboratory blood tests, fewer additional consultations, and lower total medical
The Conflict of Interest statement associated with this article can be found at http:// dx.doi.org/10.1016/j.arth.2013.04.054. Reprint requests: Rafael J. Sierra, M.D., Department of Orthopedic Surgery, Mayo Clinic, 200 First St SW, Rochester, MN 55905. 0883-5403/2808-0033$36.00/0 – see front matter © 2013 Elsevier Inc. All rights reserved. http://dx.doi.org/10.1016/j.arth.2013.04.054
costs. However, no study to date has defined the impact of TA on direct hospital costs in the setting of primary THA and TKA. Materials and Methods After receiving Mayo Clinic institutional review board approval, we reviewed the medical records of primary THA or TKA patients who had undergone surgery at the Mayo Clinic Rochester, Minnesota campus between January 1, 2007 and September 31, 2008. Exclusion criteria included American Society of Anesthesiologists (ASA) physical status classification [21] greater than II, bilateral procedures up to 90 days following index admission, unicompartmental knee arthroplasty, and revision surgery. Also, in accordance with the Minnesota Research Authorization Statute and the institutional review board, patients who denied research authorization for use of their medical records in research were excluded from the study. All patients received treatment from one of six adult reconstruction orthopedic surgeons. During the study period, three surgeons routinely used TA while three others did not. A standard dose of 1 g of TA was given at incision and again at closure. Relative contraindications for TA use included recent cerebrovascular accident, deep vein thrombosis (DVT) or pulmonary embolism (PE), cardiac stent placement within 3 months, or concerns raised by the anesthesiologist. A transfusion threshold of hemoglobin b8 g/dL was routinely utilized. Data on clinical and surgical characteristics as well as complications were obtained from the institutional joint registry and verified through chart review of the electronic medical records.
138
B.P. Gillette et al. / The Journal of Arthroplasty 28 Suppl. 1 (2013) 137–139
Initiated in 1969, the Mayo Clinic Total Joint Registry contains detailed baseline and ongoing follow-up data to ascertain clinical and patientreported outcomes and maintains an overall clinical follow-up rate of 80% at 20 years [22,23]. Cost data were obtained from an institutional cost and utilization database that contained standardized inflation-adjusted cost estimates of each service or procedure provided to Mayo patients in constant United States (US) dollars [24,25]. All payers were included, but for classification purposes, costs were grouped as Medicare Part A or Medicare Part B [26] (See Fig.). Since outliers will impact the overall cost of a given procedure for hospitals, the mean cost per patient is a more useful measurement for hospital budgetary estimates and therefore is the most appropriate statistical measure for fiscal analysis [27–29]. Mean and median costs, however, were both evaluated. Intrapair estimated mean differences in total hospital costs (Medicare part A and B), as well as operating room, blood/lab, room & board, and pharmacy costs were compared using paired t tests with derived P values and 95% confidence intervals (CI). Results Of the 1018 patients included in this study, 580 patients received TA while 438 in the control group did not. Body mass indices were similar (30.2 vs. 30.4 kg/m 2, P = .19), however the non-TA cohort was statistically older by 2.6 years (60.7 vs. 63.3 years, P b .001). The estimated mean hospital total cost and subgroup costs are shown in Table. Overall, the total hospital, room & board, operating room, and blood/laboratory costs were significantly lower for patients who received TA with an estimated mean hospital total cost savings of $879. The pharmacy cost was significantly higher in the TA group with an estimated mean cost difference of $140. The transfusion rate was significantly increased in patients not receiving TA (8.9% vs. 21.6%, P b .0001). When a transfusion occurred, the mean number of units transfused was 1.8. Discussion Factors limiting tranexamic acid (TA) use in total joint arthroplasty likely include lack of familiarity with the drug among orthopedic surgeons [30], concern regarding thromboembolic risk, and associated
cost of the drug and its administration. In light of the growing body of evidence showing the effectiveness of antifibrinolytic therapy on perioperative transfusion rates and blood loss, our primary goal was to determine the cost of TA use, from the hospital perspective, in healthy primary THA and TKA patients. Since THA and TKA are high volume procedures, they have the greatest potential for cost savings on a per patient basis due to the cumulative effect. As expected, we found a statistically significant increase in pharmacy costs, reflecting the cost of TA administration. However, the increase in pharmacy costs was more than offset by significant reductions in operating room, blood/laboratory, and room & board costs. This resulted in $879 lower estimated mean hospital total costs in the TA group compared to the control group. Many factors may contribute to the significant cost savings observed. Eliminating the need for blood transfusion likely had a direct impact of the estimated mean hospital blood and laboratory costs. When a transfusion occurred in this study, the average patient received two units of packed red blood cells representing a significant cost. Institutional costs associated with blood transfusion vary widely but have recently been shown to cost upwards of $1200 per hospitalization [17]. Additionally, higher initial postoperative hemoglobin values (i.e. N 10 g/dL) may have resulted in fewer laboratory tests being ordered and a secondary reduction in laboratory costs. Along with this higher hemoglobin, patients may have less fatigue, fewer hypotensive episodes, earlier ambulation and hospital discharge thereby decreasing room & board costs. A significant strength in this study is the use of the institutional cost and utilization database [24,25]. Since 1987, this unique database has provided a standardized, inflation-adjusted estimation of cost of procedures and services within Mayo Clinic and its affiliated hospitals. Using accepted valuation techniques, this database minimizes discrepancies between billed charges and true resource use by adjusting to national cost norms. It provides an estimated cost for each line item and can then aggregate data into categories. This process allows for a highly detailed, rigorous economic analysis between subjects that would otherwise have been very difficult to perform. There are some potential limitations of this study. First, this is a retrospective, nonrandomized study from single institution and as such, the results may not be generalizable to other institutions. Moreover the non-TA cohort was statistically older by 2.6 years, and
Episode of Care Costs
Indirect Costs
Direct Costs
Cost of lost productivity related to the morbidly and mortality of the disease state
Costs that include available recourses such as physical supplies, labor and time
• • • • • • • • •
Medicare Part A Room and board Surgical supplies Hospital supplies Medications Joint Prosthesis Equipment (IV pumps, Ventilators) Physical Therapy Anesthesia supplies Labs
Intangible Costs Costs associated with Pain and Suffering.
• • • •
Medicare Part B Physician Costs Additional Physician Consults Anesthesiologist Time Radiologist Time
Fig. Classification of episode of care costs.
B.P. Gillette et al. / The Journal of Arthroplasty 28 Suppl. 1 (2013) 137–139
139
Table Total and Subgroup Hospital Costs (Medicare Part A) for Patients With and Without Tranexamic Acid.
Total Hospital Costs Room & Board Operating Room Blood/lab Pharmacy a b
TA Cohorta $, (n = 580)
Control Cohorta $, (n = 438)
15,099 (14,912) ± 2322
15,978 (15,161) ± 4647
2835 (2746) 3418 (3397) 361 (279) 921 (884)
± ± ± ±
729 313 321 238
3292 (2853) 3640 (3635) 500(339) 781 (722)
± ± ± ±
2096 461 480 580
Cost Differenceb $
P Value
−879 (−403 to −1353)
b0.0002
−457 −222 −139 140
b0.0001 b0.0001 b.0001 b.0001
(−252 to −663) (−171 to −272) (−87 to −191) (197 to 82)
Values are presented as mean (median) ± SD. Intrapair differences are calculated as patients with TA minus patients without TA (control) and reporting a 95% confidence interval.
variability exists in surgeon preferences with postoperative care. By limiting our study population to healthy patients (ASA class II or less), the likelihood of cost difference due to an imbalance of comorbidity severity between groups is reduced. A matched design for age, comorbidities, BMI, and other variables would be most effective to reduce confounding variables. With regard to cost analysis, a single institution’s costs may lack external validity since specific institutional costs vary widely depending on negotiated contracts and product volume. However, by using standardized, estimated costs based on published and accessible data, this lack of applicability is minimized. Lastly, an intrinsic weakness to any joint registry is recording errors or lack of appropriate follow-up. This limitation was managed, however, by manual chart review of the electronic medical records for critical study components. This study has demonstrated that despite increased mean pharmacy cost with the administration of TA in healthy patients, concomitant reductions in operating room, blood/laboratory, and room & board costs contributed to nearly $900 total cost savings. These findings represent an opportunity for institutions to incorporate both cost-containment and improved patient care practices. Moreover, this is especially important given the expected increases in TKA and THA volumes and the national costs associated with an increase in these procedures. Even small cost savings per patient, when taken in the context of high volume procedures, have the potential to result in significant cost savings. References 1. Dunn CJ, Goa KL. Tranexamic acid: a review of its use in surgery and other indications. Drugs 1999;57:1005. 2. Eubanks JD. Antifibrinolytics in major orthopaedic surgery. J Am Acad Orthop Surg 2010;18:132. 3. Benoni G, Fredin H, Knebel R, et al. Blood conservation with tranexamic acid in total hip arthroplasty: a randomized, double-blind study in 40 primary operations. Acta Orthop Scand 2001;72(5):442. 4. Camarasa MA, Olle G, Serra-Prat M, et al. Efficacy of aminocaproic, tranexamic acids in the control of bleeding during total knee replacement: a randomized clinical trial. Br J Anaesth 2006;96(5):576. 5. Cid J, Lozano M. Tranexamic acid reduces allogeneic red cell transfusions in patients undergoing total knee arthroplasty: results of a meta-analysis of randomized controlled trials. Transfusion 2005;45:1302. 6. Gill JB, Rosenstein A. The use of antifibrinolytic agents in total hip arthroplasty: a meta-analysis. J Arthroplasty 2006;21:869. 7. Gillette BP, Desimone LJ, Trousdale RT, et al. Low risk of thromboembolic complications with tranexamic acid after primary total hip and knee arthroplasty. Clin Orthop Relat Res 2012;471(1):150. 8. Henry DA, Carless PA, Moxey AJ, et al. Anti-fibrinolytic use for minimising perioperative allogeneic blood transfusion. Cochrane Database Syst Rev 2011;3 CD001886.
9. Ho KM, Ismail H. Use of intravenous tranexamic acid to reduce allogeneic blood transfusion in total hip and knee arthroplasty: a meta-analysis. Anaesth Intensive Care 2003;31:529. 10. Kagoma YK, Crowther MA, Douketis J, et al. Use of antifibrinolytic therapy to reduce transfusion in patients undergoing orthopedic surgery: a systematic review of randomized trials. Thromb Res 2009;123:687. 11. Lemay E, Guay J, Cote C, et al. Tranexamic acid reduces the need for allogenic red blood cell transfusions in patients undergoing total hip replacement. Can J Anaesth 2004;51:31. 12. Rajesparan K, Biant LC, Ahmad M, et al. The effect of an intravenous bolus of tranexamic acid on blood loss in total hip replacement. J Bone Joint Surg Br 2009;91(6):776. 13. Veien M, Sorensen JV, Madsen F, et al. Tranexamic acid given intraoperatively reduces blood loss after total knee replacement: a randomized, controlled study. Acta Anaesthesiol Scand 2002;46:1206. 14. Yamasaki S, Masuhara K, Fuji T. Tranexamic acid reduces postoperative blood loss in cementless total hip arthroplasty. J Bone Joint Surg Am 2005;87:766. 15. Zohar E, Fredman B, Ellis MH, et al. A comparative study of the postoperative allogeneic blood-sparing effects of tranexamic acid and of desmopressin after total knee replacement. Transfusion 2001;41:1285. 16. Kurtz S, Mowat F, Ong K, et al. Prevalence of primary and revision total hip and knee arthroplasty in the United States from 1990 through 2002. J Bone Joint Surg Am 2005;87(7):1487. 17. Abraham I, Sun D. The cost of blood transfusion in Western Europe as estimated from six studies. Transfusion 1983;52(9):2012. 18. Bierbaum BE, Callaghan JJ, Galante JO, et al. An analysis of blood management in patients having a total hip or knee arthroplasty. J Bone Joint Surg Am 1999;81(1):2. 19. Moonen AF, Neal TD, Pilot P. Peri-operative blood management in elective orthopaedic surgery. A critical review of the literature. Injury 2006;37(Suppl. 5):S11. 20. Rosencher N, Boucebci KJ, Menichella G, et al. Orthopaedic Surgery Transfusion Haemoglobin European Overview: the OSTEO study (extended abstract). Transfus Clin Biol 2001;8(3):211. 21. Daabiss M. American Society of Anaesthesiologists physical status classification. Indian J Anaesth 2011;55:111. 22. Berry DJ, Kessler M, Morrey BF. Maintaining a hip registry for 25 years. Mayo Clinic experience. Clin Orthop Relat Res (344): 61, 1997. 23. Berry DJ, von Knoch M, Schleck CD, et al. Effect of femoral head diameter and operative approach on risk of dislocation after primary total hip arthroplasty. J Bone Joint Surg Am 2005;87(11):2456. 24. Maradit Kremers H, Visscher SL, Moriarty JP, et al. Determinants of direct medical costs in primary and revision total knee arthroplasty. Clin Orthop Relat Res 2013;471(1):206. 25. HCPR: HCPR-OCHEUD—introduction. Rochester, MN: Mayo Clinic Division of Health Care Policy and Research, 2006. 26. ISPOR: health care cost, quality, outcomes. ISPOR book of terms. Lawrenceville, NJ: International Society for Pharmacoeconomics and Outcomes Research; 2003. 27. Briggs A. Economic evaluation and clinical trials: size matters. Br Med J 2000;321:1362. 28. Ilfeld BM, Mariano ER, Williams BA, et al. Hospitalization costs of total knee arthroplasty with a continuous femoral nerve block provided only in the hospital versus on an ambulatory basis: a retrospective, case–control, cost-minimization analysis. Reg Anesth Pain Med 2007;32:46. 29. Thompson SG, Barber JA. How should cost data in pragmatic randomised trials be analysed? Br Med J 2000;320:1197. 30. Lee GC, Hawes T, Cushner FD, et al. Current trends in blood conservation in total knee arthroplasty. Clin Orthop Relat Res 2005;440:170.
Contents lists available at ScienceDirect
The Journal of Arthroplasty journal homepage: www.arthroplastyjournal.org
Economic Impact of Tranexamic Acid in Healthy Patients Undergoing Primary Total Hip and Knee Arthroplasty Blake P. Gillette, MD, Hilal Maradit Kremers, MD, MSc, Christopher M. Duncan, MD, Hugh M. Smith, PhD, Robert T. Trousdale, MD, Mark W. Pagnano, MD, Rafael J. Sierra, MD a r t i c l e
i n f o
Article history: Received 17 August 2012 Accepted 7 April 2013 Keywords: tranexamic acid economic impact hip and knee arthroplasty
a b s t r a c t Tranexamic acid (TA) has been shown to reduce perioperative blood loss and blood transfusion. While concern remains about the cost of antifibrinolytic medication, we hypothesized that routine use of tranexamic acid would result in lower direct hospital total cost by decreasing costs associated with blood transfusion, laboratory testing, and room & board. Patients with an American Society of Anesthesiologists (ASA) class II or less undergoing primary total hip or knee arthroplasty at a single institution during 2007–2008 were retrospectively reviewed. The estimated mean direct hospital total cost, operating room, blood/lab, room & board, and pharmacy costs were compared between patients who did and did not receive TA. The study population included 1018 patients, and 580 patients received TA. The mean direct total cost of hospitalization with and without TA was $15,099 and $15,978 (P b .0002) respectively, a difference of $879. The only increased cost associated with TA was the pharmacy cost which was $921 versus $781 (P b .0001). The routine use of tranexamic acid TA was associated with lower mean direct hospital total costs after primary total hip and knee arthroplasty as the increase in pharmacy costs was more than offset by cost savings in other categories. © 2013 Elsevier Inc. All rights reserved.
Antifibrinolytic medications, such as tranexamic acid (TA), have emerged as effective perioperative blood-preserving agents in total joint arthroplasty. TA is a lysine analogue that inhibits clot degradation by preventing plasmin from binding to newly formed clots [1,2]. Both retrospective and prospective studies, as well as subsequent meta-analyses, have shown that TA reduces perioperative blood loss and transfusion rates without an increased risk of venous thromboembolism [3–15]. However, with increasing total hip arthroplasty (THA) and total knee arthroplasty (TKA) volumes [16], escalating costs, and recent emphasis on cost-containment strategies, the economic impact of TA is an important consideration in modern orthopedic surgery. Blood transfusion during total joint arthroplasty is an expensive intervention costing approximately $1000 in addition to the potentially deleterious effects of immune suppression, wound infection, transfusion reaction, and fluid overload [17–20]. Minimizing patient exposure to blood transfusions, while maintaining higher postoperative hemoglobin levels, is beneficial from a patient care standpoint and may lead to faster recovery and shorter hospital stay. Reducing perioperative transfusions may also lead to reductions in laboratory blood tests, fewer additional consultations, and lower total medical
The Conflict of Interest statement associated with this article can be found at http:// dx.doi.org/10.1016/j.arth.2013.04.054. Reprint requests: Rafael J. Sierra, M.D., Department of Orthopedic Surgery, Mayo Clinic, 200 First St SW, Rochester, MN 55905. 0883-5403/2808-0033$36.00/0 – see front matter © 2013 Elsevier Inc. All rights reserved. http://dx.doi.org/10.1016/j.arth.2013.04.054
costs. However, no study to date has defined the impact of TA on direct hospital costs in the setting of primary THA and TKA. Materials and Methods After receiving Mayo Clinic institutional review board approval, we reviewed the medical records of primary THA or TKA patients who had undergone surgery at the Mayo Clinic Rochester, Minnesota campus between January 1, 2007 and September 31, 2008. Exclusion criteria included American Society of Anesthesiologists (ASA) physical status classification [21] greater than II, bilateral procedures up to 90 days following index admission, unicompartmental knee arthroplasty, and revision surgery. Also, in accordance with the Minnesota Research Authorization Statute and the institutional review board, patients who denied research authorization for use of their medical records in research were excluded from the study. All patients received treatment from one of six adult reconstruction orthopedic surgeons. During the study period, three surgeons routinely used TA while three others did not. A standard dose of 1 g of TA was given at incision and again at closure. Relative contraindications for TA use included recent cerebrovascular accident, deep vein thrombosis (DVT) or pulmonary embolism (PE), cardiac stent placement within 3 months, or concerns raised by the anesthesiologist. A transfusion threshold of hemoglobin b8 g/dL was routinely utilized. Data on clinical and surgical characteristics as well as complications were obtained from the institutional joint registry and verified through chart review of the electronic medical records.
138
B.P. Gillette et al. / The Journal of Arthroplasty 28 Suppl. 1 (2013) 137–139
Initiated in 1969, the Mayo Clinic Total Joint Registry contains detailed baseline and ongoing follow-up data to ascertain clinical and patientreported outcomes and maintains an overall clinical follow-up rate of 80% at 20 years [22,23]. Cost data were obtained from an institutional cost and utilization database that contained standardized inflation-adjusted cost estimates of each service or procedure provided to Mayo patients in constant United States (US) dollars [24,25]. All payers were included, but for classification purposes, costs were grouped as Medicare Part A or Medicare Part B [26] (See Fig.). Since outliers will impact the overall cost of a given procedure for hospitals, the mean cost per patient is a more useful measurement for hospital budgetary estimates and therefore is the most appropriate statistical measure for fiscal analysis [27–29]. Mean and median costs, however, were both evaluated. Intrapair estimated mean differences in total hospital costs (Medicare part A and B), as well as operating room, blood/lab, room & board, and pharmacy costs were compared using paired t tests with derived P values and 95% confidence intervals (CI). Results Of the 1018 patients included in this study, 580 patients received TA while 438 in the control group did not. Body mass indices were similar (30.2 vs. 30.4 kg/m 2, P = .19), however the non-TA cohort was statistically older by 2.6 years (60.7 vs. 63.3 years, P b .001). The estimated mean hospital total cost and subgroup costs are shown in Table. Overall, the total hospital, room & board, operating room, and blood/laboratory costs were significantly lower for patients who received TA with an estimated mean hospital total cost savings of $879. The pharmacy cost was significantly higher in the TA group with an estimated mean cost difference of $140. The transfusion rate was significantly increased in patients not receiving TA (8.9% vs. 21.6%, P b .0001). When a transfusion occurred, the mean number of units transfused was 1.8. Discussion Factors limiting tranexamic acid (TA) use in total joint arthroplasty likely include lack of familiarity with the drug among orthopedic surgeons [30], concern regarding thromboembolic risk, and associated
cost of the drug and its administration. In light of the growing body of evidence showing the effectiveness of antifibrinolytic therapy on perioperative transfusion rates and blood loss, our primary goal was to determine the cost of TA use, from the hospital perspective, in healthy primary THA and TKA patients. Since THA and TKA are high volume procedures, they have the greatest potential for cost savings on a per patient basis due to the cumulative effect. As expected, we found a statistically significant increase in pharmacy costs, reflecting the cost of TA administration. However, the increase in pharmacy costs was more than offset by significant reductions in operating room, blood/laboratory, and room & board costs. This resulted in $879 lower estimated mean hospital total costs in the TA group compared to the control group. Many factors may contribute to the significant cost savings observed. Eliminating the need for blood transfusion likely had a direct impact of the estimated mean hospital blood and laboratory costs. When a transfusion occurred in this study, the average patient received two units of packed red blood cells representing a significant cost. Institutional costs associated with blood transfusion vary widely but have recently been shown to cost upwards of $1200 per hospitalization [17]. Additionally, higher initial postoperative hemoglobin values (i.e. N 10 g/dL) may have resulted in fewer laboratory tests being ordered and a secondary reduction in laboratory costs. Along with this higher hemoglobin, patients may have less fatigue, fewer hypotensive episodes, earlier ambulation and hospital discharge thereby decreasing room & board costs. A significant strength in this study is the use of the institutional cost and utilization database [24,25]. Since 1987, this unique database has provided a standardized, inflation-adjusted estimation of cost of procedures and services within Mayo Clinic and its affiliated hospitals. Using accepted valuation techniques, this database minimizes discrepancies between billed charges and true resource use by adjusting to national cost norms. It provides an estimated cost for each line item and can then aggregate data into categories. This process allows for a highly detailed, rigorous economic analysis between subjects that would otherwise have been very difficult to perform. There are some potential limitations of this study. First, this is a retrospective, nonrandomized study from single institution and as such, the results may not be generalizable to other institutions. Moreover the non-TA cohort was statistically older by 2.6 years, and
Episode of Care Costs
Indirect Costs
Direct Costs
Cost of lost productivity related to the morbidly and mortality of the disease state
Costs that include available recourses such as physical supplies, labor and time
• • • • • • • • •
Medicare Part A Room and board Surgical supplies Hospital supplies Medications Joint Prosthesis Equipment (IV pumps, Ventilators) Physical Therapy Anesthesia supplies Labs
Intangible Costs Costs associated with Pain and Suffering.
• • • •
Medicare Part B Physician Costs Additional Physician Consults Anesthesiologist Time Radiologist Time
Fig. Classification of episode of care costs.
B.P. Gillette et al. / The Journal of Arthroplasty 28 Suppl. 1 (2013) 137–139
139
Table Total and Subgroup Hospital Costs (Medicare Part A) for Patients With and Without Tranexamic Acid.
Total Hospital Costs Room & Board Operating Room Blood/lab Pharmacy a b
TA Cohorta $, (n = 580)
Control Cohorta $, (n = 438)
15,099 (14,912) ± 2322
15,978 (15,161) ± 4647
2835 (2746) 3418 (3397) 361 (279) 921 (884)
± ± ± ±
729 313 321 238
3292 (2853) 3640 (3635) 500(339) 781 (722)
± ± ± ±
2096 461 480 580
Cost Differenceb $
P Value
−879 (−403 to −1353)
b0.0002
−457 −222 −139 140
b0.0001 b0.0001 b.0001 b.0001
(−252 to −663) (−171 to −272) (−87 to −191) (197 to 82)
Values are presented as mean (median) ± SD. Intrapair differences are calculated as patients with TA minus patients without TA (control) and reporting a 95% confidence interval.
variability exists in surgeon preferences with postoperative care. By limiting our study population to healthy patients (ASA class II or less), the likelihood of cost difference due to an imbalance of comorbidity severity between groups is reduced. A matched design for age, comorbidities, BMI, and other variables would be most effective to reduce confounding variables. With regard to cost analysis, a single institution’s costs may lack external validity since specific institutional costs vary widely depending on negotiated contracts and product volume. However, by using standardized, estimated costs based on published and accessible data, this lack of applicability is minimized. Lastly, an intrinsic weakness to any joint registry is recording errors or lack of appropriate follow-up. This limitation was managed, however, by manual chart review of the electronic medical records for critical study components. This study has demonstrated that despite increased mean pharmacy cost with the administration of TA in healthy patients, concomitant reductions in operating room, blood/laboratory, and room & board costs contributed to nearly $900 total cost savings. These findings represent an opportunity for institutions to incorporate both cost-containment and improved patient care practices. Moreover, this is especially important given the expected increases in TKA and THA volumes and the national costs associated with an increase in these procedures. Even small cost savings per patient, when taken in the context of high volume procedures, have the potential to result in significant cost savings. References 1. Dunn CJ, Goa KL. Tranexamic acid: a review of its use in surgery and other indications. Drugs 1999;57:1005. 2. Eubanks JD. Antifibrinolytics in major orthopaedic surgery. J Am Acad Orthop Surg 2010;18:132. 3. Benoni G, Fredin H, Knebel R, et al. Blood conservation with tranexamic acid in total hip arthroplasty: a randomized, double-blind study in 40 primary operations. Acta Orthop Scand 2001;72(5):442. 4. Camarasa MA, Olle G, Serra-Prat M, et al. Efficacy of aminocaproic, tranexamic acids in the control of bleeding during total knee replacement: a randomized clinical trial. Br J Anaesth 2006;96(5):576. 5. Cid J, Lozano M. Tranexamic acid reduces allogeneic red cell transfusions in patients undergoing total knee arthroplasty: results of a meta-analysis of randomized controlled trials. Transfusion 2005;45:1302. 6. Gill JB, Rosenstein A. The use of antifibrinolytic agents in total hip arthroplasty: a meta-analysis. J Arthroplasty 2006;21:869. 7. Gillette BP, Desimone LJ, Trousdale RT, et al. Low risk of thromboembolic complications with tranexamic acid after primary total hip and knee arthroplasty. Clin Orthop Relat Res 2012;471(1):150. 8. Henry DA, Carless PA, Moxey AJ, et al. Anti-fibrinolytic use for minimising perioperative allogeneic blood transfusion. Cochrane Database Syst Rev 2011;3 CD001886.
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