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Prevalence of anaemia in orthopaedic surgery and perioperative blood transfusions
- Maria J. Colomina, M. Basora (22 January 2008)
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Maria J. Colomina, Department of Anaesthesia Hospital Universitario Vall d'Hebron - Barcelona, M. Basora
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To the Editor: In reference to the recently published study by Saleh et al., Prevalence of anaemia before major joint arthroplasty and the potential impact of preoperative investigation and correction on perioperative blood transfusion,1 we should like to reflect on some points and comment on the results of this study, comparing them with the data obtained in an observational, epidemiological study on transfusion practice in the hospital setting in Spain.2 The authors provide data from a retrospective in-hospital audit and state that there are no recent studies on the epidemiology of anemia in these patients. They have omitted citing two large, prospective, multicenter studies, one from the USA 3 containing 9842 patients and one from Europe, the OSTHEO study,4 with 3996 patients, that describe perioperative transfusion practice in orthopedic surgery (including the patients’ anemia status), as well as other studies highly relevant to this topic 5 6. In 2004 in Spain, an observational, epidemiological study was carried out to investigate preoperative hemoglobin (Hb) levels, number of blood transfusions performed, and use of blood-sparing techniques in elective major surgery 2. Among a total sample of 359 patients recruited in a 5-day period in 18 hospitals, 199 underwent major orthopedic surgery: 78 patients (21.7%) had primary or revision hip arthroplasty, 87 (24.2%) knee arthroplasty, and 34 (9.4%) spine surgery. Mean preoperative Hb was 135 ± 14 g litre-1, and 25% of patients presented levels below 130 g litre-1. The mean transfusion index was 27.1%, a figure similar to data reported by Saleh et al (21.3%). Among patients with Hb <130 g litre-1, transfusion was performed in 79.1% in hip surgery, 38.8% in knee surgery, and 100% in spine surgery. Seven patients in the Spanish series (3.5%) presented preoperative Hb levels less than 110 g litre-1 and 6 of them required transfusion (85.2%) with a mean of 2 units per patient. In the study by Saleh et al, 7.1% of patients had Hb less than 110 g litre-1, and there was a considerable difference in the transfusion requirement (42%) as compared to that of our series (85.2%). Some factors that could explain this difference, but were not mentioned in Saleh’s study, might be the transfusion threshold, extent of perioperative bleeding, or the use of pharmacological agents to decrease blood loss. Patients in the Spanish study were transfused at mean hemoglobin levels of 84 ± 13 g litre-1 with 1.8 ± 0.7 units per patient, indicating greater blood loss at surgery in this series, possibly because of the diverse surgical teams involved. Median preoperative Hb in the Spanish study was 135 g litre-1, and 25% had values below 130 g litre-1. Such low preoperative Hb is proven to be the most important predictive factor of transfusion, regardless of whether it falls below the lower normal limit for this parameter. This causal relationship has been established in studies done in other types of surgery: hip replacement, 7-9 knee replacement, 10 11 major orthopedic surgery, 12 rectal cancer surgery, 13 and coronary revascularization. 14 15 These data indicate that Hb should be optimized before patients undergo surgery, whenever this measure is possible according to time and means. Nevertheless, Saleh et al conclude that it is not strictly necessary to treat preoperative anemia from the standpoint of optimizing transfusion use. We believe it is imprecise to derive this conclusion solely on the absolute number of transfused units required in patients with anemia as compared to those without. Other important aspects of transfusion practice are not assessed, such as the influence on morbidity and mortality, tolerance to anemia according to the patient’s associated comorbid conditions, the cost of transfusion, and factors related with immunomodulation. The authors analyze the type of anemia using mean cell volume (MCV) and mean cell hemoglobin (MCH) values. Patients with normocytic-normochromic anemia are labeled “anemia of chronic disease”, without taking into consideration ferritin or C-reactive protein values, or the elevated percentage of mixed anemia in chronic disease associated with iron deficit. The authors assume that only microcytic anemia is associated with iron deficit. However, before microcytosis appears, there is a deficit in iron deposition and a subsequent functional iron deficit, which, with progression, leads to microcytosis. 16 All patients with iron deficiency or a functional iron deficit, and those with mixed anemia can benefit from iron administration, and Hb will also improve in most of them. The perfunctory analysis of anemia performed in Saleh’s study may not be an adequate basis for determining anemia type, or for indicating iron or erythropoietin administration. The authors found that the predictive factors for transfusion in their study population were age, revision hip surgery, and preoperative Hb level. It is currently known that the percentage of surgical patients who undergo allogeneic blood transfusion depends on the type of patients included and their comorbid conditions, the type of surgery, and the degree to which blood-sparing techniques are used. These factors have been demonstrated in large multicenter studies developed in orthopedic surgery, in which the transfusion rate ranges from 18% to 25%, 3 4 figures similar to that reported in this study. Saleh et al. do not specify whether patients undergoing revision hip surgery had the primary surgery in the previous months, or how many were reoperated for infection. Revision surgery for infection is usually performed in two stages, the first to remove the infected prosthesis and insert a spacer, and the second to place the definitive prosthesis once infection had resolved. This issue could be a confounding factor, with revision surgery, itself, identified as a factor predictive of transfusion and these patients having a lower preoperative Hb because of the previous intervention or infection. 17 The authors state that preoperative anemia treatment is unlikely to have an impact on transfusion. Nonetheless, the European Council 18 as well as the Spanish Health Ministry in its Royal Decree 1088/2005 19 establish that attempts to anticipate blood loss and normalize Hb and iron reserves are necessary, as is promoting optimal blood product use and blood- sparing. In addition, guidelines formulated in Scotland, which were cited by the authors in the section on hemoglobin transfusion thresholds, indicate that where possible, anemia should be corrected prior to major surgery to reduce exposure to allogeneic transfusion. 20 In the Spanish study, we found that operative blood loss was underestimated and use of the available blood-sparing resources was sub-optimal. 2 In keeping with Saleh et al, we believe that it is necessary to determine the current status of transfusion practice in our surgery setting. Knowledge of this practice in each center will allow the implicated specialists – surgeons, anesthesiologists and hematologists – to improve preoperative Hb and apply adequate blood-sparing techniques through a team approach, analyzing the efficacy of the measures used and adapting to the patient’s needs, with the goal of avoiding unnecessary transfusion and freeing up resources. The authors state that their current transfusion requirements may have decreased following incorporation of perioperative cell salvage in their standard care for patients undergoing revision and high-risk surgery. In their conclusions, they mention that the most highly indicated group for preoperative anemia treatment and use of perioperative cell salvage are patients with Hb lower than 110 g litre-1 or those undergoing revision hip surgery. Since these aspects were not assessed among the aims of the study and are only the authors’ perceptions, we can only consider them as having little relevance. To conclude, we believe that there is still little available information on transfusion practice. In general, transfusion protocols are not extensively used, and we are unaware of the transfusion needs in our setting, the standards of good transfusion practice, or the best blood- sparing strategies. Thus, in keeping with the work of Saleh et al., we continue asking ourselves if it is necessary to optimize preoperative Hb in surgery with a high associated risk of considerable blood loss. Are we on the right road? References 1 Saleh E, McClelland DB, Hay A, et al. Prevalence of anaemia before major joint arthroplasty and the potential impact of preoperative investigation and correction on perioperative blood transfusions. Br J Anaesth 2007; 99: 801-8 2 Basora M, Colomina MJ, Moral V, et al. Is red-blood cell transfusion a usual practice in major surgery? Spanish current practice in blood management. Eur J Anaesth 2006; 23: 87 3 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: 2-10 4 Rosencher N, Kerkkamp HE, Macheras G, et al. Orthopedic Surgery Transfusion Hemoglobin European Overview (OSTHEO) study: blood management in elective knee and hip arthroplasty in Europe. Transfusion 2003; 43: 459 -69 5 Borghi B, Oriani G, Bassi A. Blood saving program: a multicenter Italian experience. Int J Artif Organs 1995; 18: 150-8 6 Larbuisson R, Lamy M. Belgian Biomed Study concerning transfusion for surgery. Acta Anaesthesiol Belg 1998; 49: 241-2 7 Nuttall GA, Santrach PJ, Oliver WC, Jr., et al. The predictors of red cell transfusions in total hip arthroplasties. Transfusion 1996; 36: 144-9 8 Nuttall GA, Santrach PJ, Oliver WC, Jr., et al. A prospective randomized trial of the surgical blood order equation for ordering red cells for total hip arthroplasty patients. Transfusion 1998; 38: 828-33 9 Aderinto J, Brenkel IJ. Pre-operative predictors of the requirement for blood transfusion following total hip replacement. J Bone Joint Surg Br 2004; 86: 970-3 10 Aderinto J, Brenkel IJ, Chan P. Natural history of fixed flexion deformity following total knee replacement: a prospective five-year study. J Bone Joint Surg Br 2005; 87: 934-6 11 Bong MR, Patel V, Chang E, et al. Risks associated with blood transfusion after total knee arthroplasty. J Arthroplasty 2004; 19: 281-7 12 Salido JA, Marin LA, Gomez LA, et al. Preoperative hemoglobin levels and the need for transfusion after prosthetic hip and knee surgery: analysis of predictive factors. J Bone Joint Surg Am 2002; 84: 216-20 13 Benoist S. Perioperative transfusion in colorectal surgery. Ann Chir 2005; 130: 365-73 14 Isomatsu Y, Tsukui H, Hoshino S, Nishiya Y. Predicting blood transfusion factors in coronary artery bypass surgery. Jpn J Thorac Cardiovasc Surg 2001; 49: 438-42 15 Arora RC, Legare JF, Buth KJ, et al. Identifying patients at risk of intraoperative and postoperative transfusion in isolated CABG: toward selective conservation strategies. Ann Thorac Surg 2004; 78: 1547-54 16 Suominen P, Punnonen K, Rajamaki A, Irjala K. Serum transferrin receptor and transferrin receptor-ferritin index identify healthy subjects with subclinical iron deficits. Blood 1998; 92: 2934-9 17 Weber EW, Slappendel R, Prins MH, et al. Perioperative blood transfusions and delayed wound healing after hip replacement surgery: effects on duration of hospitalization. Anesth Analg 2005; 100: 1416-21 18 Directiva 2004/33/CE de la comisión por la que se aplica la Directiva 2002/98/CE del Parlamento Europeo y del Consejo en lo que se refiere a determinados requisitos técnicos de la sangre y los componentes sanguíneos. Diario Oficial de la Unión Europea, 25-40. 22-3-2004. 19 REAL DECRETO 1088/2005, de 16 de septiembre, por el que se establecen los requisitos técnicos y condiciones mínimas de la hemodonación y de los centros y servicios de transfusión. BOE 225, 31288- 31304. 20 Perioperative blood transfusion for elective surgery. A National Clinical Guideline (SIGN). Available from www.sign.ac.uk. Accessed December 15, 2007 Conflict of Interest:None declared |
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