O R I G I N A L A R T I C L E
Manuel Mun˜oz ÆDaniel ArizaÆ Marı´a J. Garcera´n Aurelio Go´mez ÆArturo Campos
Benefits of postoperative shed blood reinfusion in patients undergoing
unilateral total knee replacement
Received: 20 July 2004 / Published online: 9 April 2005 Springer-Verlag 2005
Abstract IntroductionIn patients undergoing total knee replacement (TKR), most of the measured blood loss occurs during the postoperative period, and 30–50% of these patients receive allogeneic blood transfusion (ABT). For this reason, the salvage and return of un-washed filtered shed blood (USB) from postoperative drainage may represent an alternative to ABT in these patients. We have, therefore, evaluated the clinical util-ity of USB return in TKR patients, with a special focus on patients with mild anaemia. Materials and methods
Data from 200 TKR patients (group 2) receiving USB within the first 6 postoperative hours (ConstaVac CBC II, Sryker) were prospectively collected. A retrospective series of 100 TRK patients served as the control group (group 1). Results USB return was possible in 162 pa-tients who received a mean of 0.98±0.4 U/pte, without any clinically relevant incident. Return of USB de-creased both the percentage of patients with ABT (48% vs 11%, for groups 1 and 2, respectively; p<0.01) and the ABT units/patient index (1.31±1.27 vs 0.29±0.87 units/patient, respectively; p<0.01). A transfusion pro-tocol was not established, but there was no difference between groups with respect to either perioperative Hb levels or overall transfusion index, indicating that the
transfusion criteria were uniform. However, for the subgroups of patients who needed ABT, the pre-operative Hb level was 1 g/dL lower in those receiving USB (13.4±1.4 vs 12.4±1.2 g/dL;p<0.05). There was no difference in the postoperative complication rate, and patients in group 2 recovered the ability to walk 1 day earlier, and their hospital stay was 3 days shorter than in group 1 (p<0.01). Conclusions Return of USB after TKR seems to shorten the hospital stay and effectively reduce postoperative requirements for ABT, especially in patients with preoperative Hb >13 g/dL. For pa-tients with preoperative Hb <13 g/dL, although the return of USB also decreased the requirements for ABT, a further reduction will probably be obtained with the addition of another blood-saving method.
Keywords Total knee replacement ÆAllogeneic transfusionÆ AnaemiaÆ Postoperative blood salvageÆ
Length of hospital stay
Introduction
Unilateral total knee replacement (TKR) can result in a substantial blood loss, and 30–50% of these patients receive allogeneic blood transfusion (ABT) [15, 18]. Since allogeneic blood is a scarce and increasingly expensive resource, and ABT is not a risk-free therapy, different methods to avoid ABT in these patients have been developed [1, 22]. Among them, preoperative autologous blood donation, perioperative blood salvage, and administration of drugs to either reduce blood loss (aprotinin, tranexamic acid) or stimulate erythrocyte production (iron, human recombinant erythropoietin) have been tried with different degrees of effectiveness [1, 22].
Preoperative autologous blood donation (PAD) is regarded in many countries as the standard care for major blood-losing operations, with the aim of mini-mising the exposure to ABT [20], and a very recent
M. Mun˜oz (&)
GIEMSA, School of Medicine, University of Ma´laga, Campus de Teatinos, s/n, 29071 Ma´laga, Spain E-mail: [email protected]
Fax: +34-952-131534
D. ArizaÆA. Go´mez
Department of Anaesthesiology,
University Hospital ‘Virgen de la Victoria’, Ma´laga, Spain
M. J. Garcera´n
Department of Orthopaedic Surgery, University Hospital ‘Virgen de la Victoria’, Ma´laga, Spain
A. Campos
Department of Haematology,
University Hospital ‘Virgen de la Victoria’, Ma´laga, Spain
meta-analysis of randomised controlled trials has found that for orthopaedic surgery, PAD reduced the proba-bility of receiving an ABT by 84% (RR 0.16, 95%CI 0.07–0.36), although it increased the risk of exposure to any kind of transfusion, whereas perioperative cell sal-vage (CS) reduced this probability by 65% (RR 0.35, 95%CI 0.24–0.52) [2].
In a previous meta-analysis, it was concluded that CS decreased the frequency of exposure to allogeneic blood, without differences between devices producing either washed (RR 0.39, 95%CI 0.30–0.51) or un-washed cells (RR 0.35, 95%CI 0.26–0.46), when com-pared with a control [8]. However, though there may be substantial hidden blood loss due to bleeding into the tissues and residual blood in the joint following TKA, 50% of the true total loss occurs during the postop-erative period [19], and consequently, salvage and re-turn of unwashed filtered shed blood (USB) from postoperative drainage may represent an alternative to ABT in these patients.
In our hospital this blood-saving technique has been used since May 2002, and we have, therefore, evaluated the utility of USB return to reduce exposure to ABT in TRK patients, with a special focus on patients with mild anaemia. As secondary end-points, we analysed the impact of USB return on both the rate of postoperative complications and the length of hospital stay.
Patients and methods
Data from 200 primary TRK patients operated on between May 2002 and December 2003 and receiving USB were prospectively collected (group 2). A retro-spective series of 100 TRK patients operated on by the same surgical team between January 2000 and Febru-ary 2001 and not receiving USB served as the control group (group 1). All surgical procedures involved the application of a tourniquet that was deflated before knee closure, using a total condylar knee (Duracon, Stryker, USA), with the tibial component being ce-mented.
The anaesthesiologist, who was unaware of the study, estimated blood losses in both the operation theatre and the anaesthesia recovery unit, and performed the rein-fusion of USB. In the ward, measurement of postoper-ative blood loss and decisions on postoperative transfusions were made by the attending surgeon. For calculation of requirements for ABT, one unit of packed red cells was considered as one blood unit.
Postoperative blood salvage and reinfusion
At the end of surgery, the collection blood canister (ConstaVac CBC II, Stryker, USA) was connected to two drainage catheters through a Y-connector, and USB was collected without anticoagulant at a negative
pressure of 25 mmHg and reinfused within the first 6 postoperative hours. The canister is connected to the reinfusion bag to which USB is transferred, scrapping the last 60–80 mL to minimize fat particles and other debris being transfused to the patient, and allowing for several returns if needed. A 40-lm screen filter (SQ40SJKL, Pall, UK) was intercalated in the patient’s line to eliminate microaggregates. The volume of recovered USB was converted into blood units accord-ing to the expression: U=USB volume (ml)xUSB hae-matocrit (%)/400 (ml) [16]. Patients in group 1 received a standard drainage, without reinfusion of USB.
Clinical data
A set of demographic and clinical data was collected for all patients, including age, gender, height, weight, co-morbidities, preoperative treatments, type of anaes-thesia, tourniquet and operation time, intra- and post-operative blood loss, volume of USB returned, number of ABT, perioperative Hb levels, deep venous throm-bosis, pulmonary embolism, infection and length of hospital stay (LOS).
Statistical analysis
Statistical analysis of the results was performed using Student’s t-test, the chi-square test, and Fischer’s exact test. Linear regression analysis was also performed (SPSS 12.0 package, licensed to the University of Ma´laga).
Results
There were no differences in age, height, weight, co-morbidities or preoperative treatments between groups, although there were more women in group 2 (67% vs 80%, for group 1 and 2, respectively;p<0.01) (Tables1 and2). Similarly, perioperative Hb levels and blood loss were not different in either group (Table1). In group 2, USB return was possible in 162 patients who received a mean of 0.98±0.4 units per patient, without any clini-cally relevant incident. With respect to the control group, the percentage of patients with ABT (RR 0.23;
p<0.01) and packed red cell/patient index were lower in the USB group (1.31±1.27 vs 0.29±0.87 units/patient, respectively; p<0.01) (Table 1). The differences in transfusion requirements persisted even after the pa-tient’s stratification according to a preoperative Hb >13 g/dL (RR 0.08) or <13 g/dL (RR 0.39) (Table2). Preoperative Hb levels were compared after each group of patients was further subdivided into two sub-groups, according to the need for ABT. There was no difference in preoperative Hb level between the sub-groups of patients that needed no supplementary ABT
(13.8±1.3 vs 13.6±1.2, for groups 1 and 2, respectively; NS). For patients that required ABT, preoperative Hb levels were 1 g/dL lower in the USB group (13.4±1.4 vs 12.4±1.2 g/dL, for groups 1 and 2, respectively;
p<0.05).
There were no statistically significant differences in the postoperative complication rate: 4 in group 1 (1 wound infection, 2 deep venous thrombosis, 1 pul-monary embolism) and none in group 2. However, pa-tients in group 2 recovered the ability to walk 1 day earlier and had a 3 days shorter LOS compared with patients in group 1 (p<0.01) (Tables1 and2). Finally, in the regression analysis transfusion was the only var-iable significantly associated with LOS. However, there was a negative correlation between the volume of USB returned and LOS (r 0.254;p<0.002), and a positive correlation between the volume of ABT and LOS (r0.188;p<0.04).
Discussion
Postoperative return of shed blood is an established method to reduce the need for perioperative ABT, with total knee arthroplasty being the operation where it has been used the most. There are a number of devices for collecting postoperative shed blood, the principal dif-ferentiating characteristic being the existence or not of a washing process for the salvaged blood. However, in knee surgery, this procedure is normally performed by using devices that recover and re-transfuse shed blood to the patient as USB.
In regard to clinical results, although there are some concerns about the use of USB and published series against the procedure, the re-infusion of USB has been shown to be effective in reducing the requirements for ABT [11, 12]. In addition, a meta-analysis of the
effec-Table 2 Demographic and clinical data from patients undergoing total knee replacement, with (group 2) or without (group 1) postop-erative shed blood salvage and return, stratified according to preoppostop-erative haemoglobin level
Haemoglobin £13 g/dL Haemoglobin >13 g/dL
Group 2 Group 1 Group 2 Group 1
Patients,n(%) 74 (37) 32 (32) 126 (63) 68 (68)
Age (years) 68±7 67±9 69±5 66±9
Gender (M/F) 15/59 9/23 25/101a 24/44
Preoperative Hb (g/dL) 12.2±0.7b 12.2±1.0c 14.2±0.8 14.3±1.0
ABT index (U/patient) 0.64±1.2a,b 1.50±1.43 0.12±0.52a 1.22±1.53
Patients with ABT,n(%) 17 (23)a,b 19 (59.4) 5 (3.2)a 29 (42.6)
Postoperative blood loss (mL) 760±346 808±380 678±345 875±491
Blood management costs (euros) 203±142 255±195 155±54a 213±204
Length of hospital stay (days) 13.4±2.9a 16.8±4.8 13.5±3.0a 16.1±5.3
ap<0.01 (group 1 vs group 2, for each preoperative Hb level) bp<0.01 (within group 2, according to preoperative Hb level) c
p<0.01 (within group 1, according to preoperative Hb level)
Table 1 Demographic and clinical data from patients undergoing total knee replacement, with (group 2) or without (group 1) postop-erative shed blood salvage and return [ABTallogeneic blood transfusion (packed red cells)]
Group 1 Group 2
Patients (n) 100 200
Anaesthesia (S/P) 61/39 188/12*
Operation time (min) 105±30 96±24
Tourniquet time (min) 59±26 55±17
Blood loss (mL):
Intraoperative 123±165 118±101
Postoperative 953±428 705±349
Haemoglobin (g/dL):
Preoperative 13.6±1.4 13.5±1.2
Postoperative 24–48 h 10.4±1.4 10.4±1.3
Discharge 10.8±1.3 10.5±1.3
Patients with ABT,n(%) 48 (48) 22 (11)**
Transfusion index (U/patient):
Allogeneic 1.31±1.27 0.29±0.87**
Autologous 0 0.98±0.40**
Postoperative complications,n(%) 4 (4) 0 (0)
Ability to walk (days) 7±2 6±2**
Length of hospital stay (days) 16±5 13±3**
*p<0.05, for group 2 vs group 1 **p<0.01, for group 2 vs group 1
tiveness of cell salvage in minimising perioperative allogeneic transfusion concluded that, in orthopaedic surgery, devices producing either washed or unwashed cells decreased the frequency of exposure to allogeneic blood to a similar degree compared with a control (RR 0.30 and 0.35, respectively) [8]. However, the results of this meta-analysis have been criticized because of the small number of patients included in the studies.
In our study, we found that USB return decreased by 77% the relative risk of receiving ABT (48% vs 11%,
p<0.01; absolute risk reduction 37%) and reduced the ABT index by 1 unit in patients undergoing TKR (Ta-ble 1). A transfusion protocol was not established, but there was no difference between the groups in respect of either perioperative Hb levels or overall transfusion in-dex, indicating that the transfusion criteria were uniform (Table1). Moreover, our data are in concordance with those of 7 studies published over the last 5 years and including almost 2000 patients, showing a 68% decrease in the relative risk of receiving ABT (60% vs 19%,
p<0.01; absolute risk reduction 41%) (Table3) [4,4,6, 7,14,16,21,23], and with those of the above-mentioned meta-analysis [8]. These results seem to confirm the effectiveness of USB return to reduce the need for ABT in TKR patients.
Very recently, in a series of 365 patients who under-went surgery for TKR, Steinberg et al. [23] reported that postoperative salvage and reinfusion of USB decreased by 65% the requirements for ABT, and also reduced the packed red cell/patient index, with respect to a control group. In addition, they reported that a cut-off point of the preoperative Hb level for receiving blood transfusion was found to be 13.25 g/dL for both of them. In our series, for the subgroups of patients who needed ABT, the preoperative Hb was 1 g/dL lower in the USB group with respect to the control group (12.4±1.2 vs 13.4±1.4 g/dL; p<0.05), whereas there were no differ-ences between preoperative Hb levels for patients who required ABT. Keeping in mind that the transfusion of one blood unit should increase the patient’s Hb level by 1 g/dL, the amount of USB returned (0.98 unit per pa-tient) would account for this difference. Once again, these results supported the clinical utility of USB return. According to Steinberg et al. [23], the preoperative Hb level is a major predictor for the risk of transfusion
in TKR, and patients with preoperative Hb level >13.25 g/dL may need no blood transfusion. However, in our control series, at least one ABT was needed for 42% of the patients with preoperative Hb >13 g/dL, whereas this was true for only 3% of the patients receiving USB. For this reason, as the postoperative blood loss is unpredictable, we believe that the collector system should be of use in both anaemic and non-anaemic TKR patients to provide a wider safety margin. Return of USB presents very few adverse effects, mostly chills, febricula, tachycardia, and hypotension, which can be prevented by limiting the volume to return (max. 1000–1500 mL), using a slow infusion rate and discarding the last 50–100 mL of USB, as the ConstaVac CBC II does [11]. We did not observe any adverse effect of USB return during the study, but there was a trend to a lower rate of postoperative complications in patients receiving USB, as previously reported [13], and to a faster recovery, as suggested by the earlier ability to walk and the shorter LOS (Table1) [15]. These effects are possibly related to the decreased exposure to ABT and to the recently described immunostimulatory effect of USB [6]. In fact, blood transfusion was the only variable significantly associated with LOS, but there was a negative correlation between the volume of USB re-turned and LOS, and a positive correlation between the volume of ABT and LOS. However, it must be pointed out that though postoperative USB reinfusion seems to be beneficial, the number of patients was too small to determine a significant benefit over ABT with enough statistical power. Thus, these results need to be con-firmed by a large randomised trial.
In our community, the cost of one collection-reinfu-sion unit is about 135 euros, and the price of packed red cells plus the drainage catheters is about 180 euros. Based on these prices, for patients with preoperative Hb >13 g/dL, mean transfusion costs were 213 and 155 euros/patient for group 1 and 2, respectively (p<0.01), whereas for patients with preoperative Hb <13 g/dL, mean transfusion costs were 255 and 203 euros/patient, respectively (NS). In addition, although the return of USB effectively reduces the requirements for ABT in anaemic patients from group 2 (Table2), it became evident that some additional blood-saving method should be employed, since 23% of them still needed
Table 3 Results of some studies on the effectiveness of unwashed shed blood return (+USB) to decrease the requirements for allogeneic blood transfusion (+ABT) in total knee replacement
Study Year +USB +ABT/total
(%)
Control +ABT/total (%)
Relative risk
Henderson et al. [7] 1999 35/159 22 134/180 74 0.30
Dı´az and Moral [4] 1999 13/91 14 25/57 44 0.33
Peter et al. [14] 2001 30/160 19 67/93 72 0.26
Sinha et al. [21] 2001 8/50 22 44/50 88 0.25
Ferna´ndez et al. [5] 2002 26/81 32 56/82 68 0.47
Sanz et al. [16] 2004 43/250 17 112/250 45 0.38
Steinberg et al. [23] 2004 36/194 19 89/171 52 0.36
ABT. In this regard, the administration of erythropoie-tin (40,000 IU) plus intravenous iron (400 mg) has been shown to decrease the requirements for ABT in TKR and to be more cost-effective than other recently re-ported blood-saving protocols [3, 9, 10]. Therefore, we believe that a reasonable increase in blood management costs (+300 euros/patient) produced by supplementing USB with EPO plus intravenous iron in anaemic pa-tients would probably be offset by the reduction in both the requirements for ABT and the length of hospital stay. However, a cost-benefit analysis of these inter-ventions is difficult to make because of the complex costs involved in blood transfusion. Thus, a formal cost-benefit study is also required to address this issue.
Acknowledgements This study was financially supported by grant FIS PI 02/1826 from Instituto de Salud Carlos III (Spain) and the European Union, it was approved by the Ethics Committee of the University Hospital ‘Virgen de la Victoria’ (Ma´laga, Spain), and it complied with current Spanish laws.
References
1. Amin M, Fergusson D, Aziz A, Wilson K, Coyle D, He´bert P (2003) The cost of allogeneic red blood cells—a systematic re-view. Transf Med 13:275–285
2. Carless P, Moxey A, O’Connell D, Henry D (2004) Autologous transfusion techniques: a systematic review of their efficacy. Transf Med 14:123–144
3. Cuenca J, Martı´nez F, Garcı´a-Erce JA, Benedi JA, Larrode M, Pe´rez-Serrano L (2004) Transfusion in total knee replacement. Presurgical administration of EPO and parenteral iron (ab-stract). TATM 6 (Suppl 1):89
4. Diaz-Espallardo C, Moral-Garcı´a V (1999) Ana´lisis de la rel-acio´n coste-efectividad de un programa de autotransfusio´n en cirugı´a prote´sica primaria de rodilla y cadera. Rev Esp Ane-stesiol Reanim 46:396–403
5. Ferna´ndez CM, Rubio F, Crespo J, Acedo A (2002) Auto-transfusio´n postoperatoria en cirugı´a de rodilla. In: Mun˜oz M (ed) Anemia y transfusion en cirugı´a. SPICUM, Ma´laga, pp 432–436
6. Gharehbahian A, Haque G, Truman C, Evans R, Morse H, Newman J et al (2004) Effect of autologous salvaged blood on post-operative natural killer cell precursor frequency. Lancet 363:1025–1030
7. Henderson MS, Newman JH, Hand GCR (1999) Blood loss following knee replacement surgery, use it don’t lose it. Knee 6:125–129
8. Huet C, Salmi LR, Fergusson D, Koopman-van Gements AW, Rubens F, Laupacis A (1999) A meta-analysis of the effec-tiveness of cell salvage to minimize perioperative allogeneic blood transfusion in cardiac and orthopaedic surgery. Inter-national Study of Perioperative Transfusion (ISPOT) Investi-gators. Anesth Analg 89:861–869
9. Kourtzis N, Pafilas D, Kasimatis G (2004) Blood saving pro-tocol in elective total knee arthroplasty. Am J Surg 187:261– 267
10. Minoda Y, Sakawa A, Fukuoka S, Tada K, Takaoka K (2004) Blood management for patients with hemoglobin level lower than 130 g/l in total knee arthroplasty. Arch Orthop Trauma Surg 124:317–319
11. Mun˜oz M, Garcı´a-Vallejo JJ, Lo´pez-Andrade A, Go´mez A, Ruiz MD, Maldonado J (2001) Autotransfusio´n postoperatoria en cirugı´a ortope´dica. Un ana´lisis de la calidad, seguridad y eficacia de la sangre recuperada de los drenajes postoperatori-os. Rev Esp Anestesiol Reanim 48:131–140
12. Mun˜oz M, Garcı´a-Vallejo JJ, Ruiz MD, Romero R, Olalla E, Sebastia´n C (2004) Transfusion of post-operative shed blood: Laboratory characteristics and clinical utility. Eur Spine J 13 (Suppl 1):S107–S113
13. Newman JH, Bowers M, Murphy J (1997) The clinical advantage of autologous transfusion. A randomised, controlled study after knee replacement. J Bone Joint Surg Br 79:630–632 14. Peter VK, Radford M, Matthews MG (2001) Re-transfusion of autologous blood from wound drains: the means for reducing transfusion requirements in total knee arthroplasty. Knee 8:321–323
15. Rosencher N, Kerkkamp HE, Macheras G, Munuera LM, Menichella G, Barton DM et al (2003) Orthopedic Surgery Transfusion Hemoglobin European Overview (OSTHEO) study: blood management in elective knee and hip arthroplasty in Europe. Transfusion 43:459–469
16. Sanz Pen˜uelas RA, Torcal Abia´n F, Rodriguez A, Castro M, Pe´rez-Cerda´ F (2004) Postoperative autologous blood trans-fusion after unilateral total knee arthroplasty (abstract). 13th World Congress of Anaesthesiologists, www.wca2004.com: S004
17. Sebastia´n C, Romero R, Olalla E, Ferrer C, Garcı´a-Vallejo JJ, Mun˜oz M (2000) Postoperative blood salvage and reinfusion in spinal surgery. Blood quality, effectiveness and impact on pa-tient blood parameters. Eur Spine J 9:458–465
18. Sehat KR, Evans R, Newman JH (2000) How much blood is really lost in total knee arthroplasty? Correct blood loss man-agement should take hidden loss into account. Knee 7:151–155 19. Sehat KR, Evans RL, Newman JH (2004) Hidden blood loss following hip and knee arthroplasty. Correct management of blood loss should take hidden loss into account. J Bone Joint Surg Br 86:561–565
20. Scottish Intercollegiate Guidelines Network (2004) Periopera-tive blood transfusion for elecPeriopera-tive surgery. A national clinical guideline. www.sign.ac.uk
21. Sinha A, Sinha M, Burgert S (2001) Reinfusion of drained blood as an alternative to homologous blood transfusion after total knee replacement. Inter Orthop 25:257–259
22. Spahn DR, Casutt M (2000) Eliminating blood transfusions. Anesthesiology 93:242–255
23. Steinberg EL, Ben-Galim P, Yaniv Y, Dekel S, Menahem A (2004) Comparative analysis of the benefits of autotransfusion of blood by a shed blood collector after total knee replacement. Arch Orthop Trauma Surg 124:114–118
