Reinfusion of mediastinal blood in CABG patients: impact on homologous transfusions and rate of re-exploration

Cell Salvage at the ICU

Patient Blood Management (PBM) is a patient-centered, systemic and evidence-based approach. Its target is to manage and to preserve the patient's own blood. The aim of PBM is to improve patient safety. As indicated by several meta-analyses in a systematic literature search, the cell salvage technique is an efficient method to reduce the demand for allogeneic banked blood. Therefore, cell salvage is an important tool in PBM. Cell salvage is widely used in orthopedic-, trauma-, cardiac-, vascular and transplant surgery. Especially in cases of severe bleeding cell salvage adds significant value for blood supply. In cardiac and orthopedic surgery, the postoperative use for selected patients at the intensive care unit is feasible and can be implemented well in practice. Since the retransfusion of unwashed shed blood should be avoided due to multiple side effects and low quality, cell salvage can be used to reduce postoperative anemia with autologous blood of high quality. Implementing quality management, compliance with hygienic standards as well as training and education of staff, it is a cost-efficient method to reduce allogeneic blood transfusion. The following article will discuss the possibilities, legal aspects, implementation and costs of using cell salvage devices in an intensive care unit.

Transfusion of shed mediastinal blood reduces the use of allogenic blood transfusion without increasing complications

BACKGROUND

Reduced use of allogenic blood components is a key issue in cardiac surgery. Several methods to conserve blood have been used; reinfusion of shed mediastinal blood (RSMB) has found widespread acceptance, but the efficacy and safety are still debated. The purpose of this study was to evaluate the effects of RSMB on the use of allogenic blood components and selected complications.

MATERIAL AND METHODS

Six hundred and twenty-three consecutive cardiac surgery patients in three successive periods, of whom patients in the middle period did not receive RSMB due to manufacturer delivery problems, were evaluated. Patients and procedures were characterized by EuroSCORE. Prospective collected data were: units of transfused allogenic blood, fresh frozen plasma (FFP) and platelets, postoperative blood loss and postoperative complications such as dialysis, re-operation due to bleeding, sternal infection and stroke. Length of stay in ICU was used as a general indicator of perioperative complications.

RESULTS

The number of patients receiving allogenic blood in periods with RSMB was significantly lower (36.5% versus 54.9%, p<0.005), while no difference was seen in FFP and platelets. The average number of transfused blood units was lower in patients receiving RSMB (2.07 versus 3.41, p=0.029), while FFP (1.34 versus 2.01, p=0.11) and platelets (0.58 versus 0.95, p=0.05) were not statistically significantly different. Postoperative bleeding was lower (759 versus 967 ml, p=0.032) in the periods with RSMB.

CONCLUSION

Patients receiving RSMB were less transfused with allogenic blood and had less postoperative drainage, while the frequency of observed postoperative complications was not different from patients who did not receive RSMB.

Perioperative blood transfusion and blood conservation in cardiac surgery: the Society of Thoracic Surgeons and The Society of Cardiovascular Anesthesiologists clinical practice guideline

BACKGROUND

A minority of patients having cardiac procedures (15% to 20%) consume more than 80% of the blood products transfused at operation. Blood must be viewed as a scarce resource that carries risks and benefits. A careful review of available evidence can provide guidelines to allocate this valuable resource and improve patient outcomes.

METHODS

We reviewed all available published evidence related to blood conservation during cardiac operations, including randomized controlled trials, published observational information, and case reports. Conventional methods identified the level of evidence available for each of the blood conservation interventions. After considering the level of evidence, recommendations were made regarding each intervention using the American Heart Association/American College of Cardiology classification scheme.

RESULTS

Review of published reports identified a high-risk profile associated with increased postoperative blood transfusion. Six variables stand out as important indicators of risk: (1) advanced age, (2) low preoperative red blood cell volume (preoperative anemia or small body size), (3) preoperative antiplatelet or antithrombotic drugs, (4) reoperative or complex procedures, (5) emergency operations, and (6) noncardiac patient comorbidities. Careful review revealed preoperative and perioperative interventions that are likely to reduce bleeding and postoperative blood transfusion. Preoperative interventions that are likely to reduce blood transfusion include identification of high-risk patients who should receive all available preoperative and perioperative blood conservation interventions and limitation of antithrombotic drugs. Perioperative blood conservation interventions include use of antifibrinolytic drugs, selective use of off-pump coronary artery bypass graft surgery, routine use of a cell-saving device, and implementation of appropriate transfusion indications. An important intervention is application of a multimodality blood conservation program that is institution based, accepted by all health care providers, and that involves well thought out transfusion algorithms to guide transfusion decisions.

CONCLUSIONS

Based on available evidence, institution-specific protocols should screen for high-risk patients, as blood conservation interventions are likely to be most productive for this high-risk subset. Available evidence-based blood conservation techniques include (1) drugs that increase preoperative blood volume (eg, erythropoietin) or decrease postoperative bleeding (eg, antifibrinolytics), (2) devices that conserve blood (eg, intraoperative blood salvage and blood sparing interventions), (3) interventions that protect the patient's own blood from the stress of operation (eg, autologous predonation and normovolemic hemodilution), (4) consensus, institution-specific blood transfusion algorithms supplemented with point-of-care testing, and most importantly, (5) a multimodality approach to blood conservation combining all of the above.

Clinical efficacy of postoperative autologous transfusion of filtered shed blood in hip and knee arthroplasty

BACKGROUND

Total knee arthroplasty (TKA) or total hip arthroplasty (THA) regularly results in postoperative requirement of blood transfusion. Because of the disadvantages of allogeneic blood transfusion (ABT) such as the risk of transfusion-associated infections, incompatibility-related transfusion fatalities, or immunomodulatory effects, a continuing effort to reduce allogeneic blood transfusion is important. For this purpose, the effect of reinfusion of drain blood, via a postoperative wound drainage and reinfusion system, on the need for allogeneic blood transfusion was evaluated.

STUDY DESIGN AND METHODS

Using a prospective observational quality assessment design, we compared 135 patients scheduled for TKA or THA with a historic group of 96 patients. In the study group the Bellovac ABT autotransfusion system was used. The shed blood was returned either when 500 mL were collected or at most 6 hours after surgery. Compared were the preoperative, postoperative, and discharge hemoglobin, as well as the number of allogeneic blood transfusions.

RESULTS

There were no statistical differences between preoperative, postoperative, and discharge hemoglobin levels. Autologous transfusion reduced the number of patients receiving ABT overall from 35 percent (control) to 22 percent (study). The decrease of allogeneic transfusion requirement was most significant after TKA: from 18 percent to 6 percent (p < 0.001).

CONCLUSION

We conclude that the Bellovac ABT device reduces allogeneic blood transfusions in TKA and THA.

Safety and efficacy of perioperative cell salvage and autotransfusion after coronary artery bypass grafting: a randomized trial

BACKGROUND

The aim of this study was to ascertain whether cell salvage and autotransfusion after first time elective coronary artery bypass grafting is associated with a significant reduction in the use of homologous blood, a clinically significant derangement of postoperative clotting profiles, or an increased risk of postoperative bleeding.

METHODS

Patients were randomized to autotransfusion (n = 98) receiving autotransfused washed blood from intraoperative cell salvage and postoperative mediastinal fluid cell salvage after coronary artery bypass surgery or control (n = 102) receiving stored homologous blood only after coronary artery bypass surgery.

RESULTS

There was no statistical difference between the groups in terms of demographics, comorbidity, risk stratification, or operative details. Mean volume of blood autotransfused was 367 +/- 113 mL. Patients in the autotransfusion group were significantly less likely to receive a homologous blood transfusion compared with controls (odds ratio 0.40, 95% confidence interval [CI] 0.22-0.71) and received significantly fewer units of blood per patient compared with controls (0.43 +/- 1.5 vs 0.90 +/- 2.0 U, p = 0.02). There was no difference between the groups in terms of postoperative blood loss, fluid requirements, blood product requirements, or in the incidence of adverse clinical events (p = NS chi(2)). Autotransfusion did not produce any significant derangement of thromboelastograph values or laboratory measures of clotting pathway function (prothrombin time, activated partial thromboplastin time, fibrinogen, and fibrinogen D-dimer levels) when compared with the effect of homologous blood transfusion (p = NS, repeated measures analysis of variance [MANOVA]).

CONCLUSIONS

Autotransfusion is a safe and effective method of reducing the use of homologous bank blood after routine first time coronary artery bypass grafting.

Autotransfusion decreases blood usage following cardiac surgery -- a prospective randomized trial

INTRODUCTION

10% of blood issued by the National Blood Service (220,000) is utilised in cardiac procedures. Transfusion reactions, infection risk and cost should stimulate us to decrease this transfusion rate. We tested the efficacy of autotransfusion of washed postoperative mediastinal fluid in a prospective randomized trial.

PATIENTS AND METHODS

166 patients undergoing coronary artery bypass grafting (CABG), valve or CABG + valve procedures were randomized into three groups. The indication for transfusion was a postoperative haemoglobin (Hb) < 10 g/l or a packed cell volume (PCV) < 30. When applicable, group A patients received washed post-operative drainage fluid. Group B all received blood processed from the cardiopulmonary bypass (CPB) circuit following separation from CPB and if appropriate washed post-operative drainage fluid. Group C were controls. Groups were compared using analysis of variance.

RESULTS

There was no significant difference in age, sex, type of operation, CPB time and preoperative Hb and PCV between the groups. Blood requirements were as shown. [table - see text] Twelve patients in group A and 10 in group B did not require a homologous transfusion following processing of the mediastinal drainage fluid.

CONCLUSION

Autotransfusion of washed postoperative mediastinal fluid can decrease the amount of homologous blood transfused following cardiac surgery. There was no demonstrable benefit in processing blood from the CPB circuit as well as mediastinal drainage fluid.

Reinfusion of mediastinal blood after heart surgery

BACKGROUND

Several authors studying autotransfusion of shed mediastinal blood in patients undergoing heart operations have published conflicting results regarding reduction of the need for homologous blood transfusion. The effect on coagulation parameters is also unclear.

METHODS

In a prospective randomized study, 198 patients who underwent coronary artery bypass grafting or a valvular operation were divided into 2 groups: a group with autotransfusion of shed mediastinal blood after an operation and a control group. Continuous reinfusion of mediastinal blood was done until no drainage was present or for a period of 12 hours after the operation. The amount of blood lost and autotransfused, the number of homologous blood products transfused, and the coagulation parameters were monitored.

RESULTS

The number of patients requiring homologous blood transfusion was significantly different between the 2 groups (54/98 [55%] in autotransfused patients vs 73/100 [73%] in the control group, P =.01). The number of re-explorations for excessive bleeding was similar in the 2 groups (7/98 [7.1%] vs 8/100 [8%]), but the amount of blood collected postoperatively was higher in the autotransfused patients compared with control patients (1200 +/- 201 mL vs 758 +/- 152 mL, P =.0007). Coagulation parameters analyzed and complication rates were similar in the 2 groups after the operations.

CONCLUSION

Autotransfusion of shed mediastinal blood reduces the need for homologous blood transfusion in patients undergoing various cardiac operations. The cause of increased shed blood in patients undergoing autotransfusion remains unclear.

Safety and efficacy of shed mediastinal blood transfusion after cardiac surgery: a multicenter observational study. Multicenter Study of Perioperative Ischemia Research Group

OBJECTIVE

To examine the efficacy and safety of shed mediastinal blood (SMB) transfusion in preventing allogenic red blood cell (RBC) transfusion.

DESIGN

An observational clinical study.

SETTING

Twelve US academic medical centers.

PARTICIPANTS

Six hundred seventeen patients undergoing elective primary coronary artery bypass grafting.

INTERVENTIONS

Patients were administered SMB transfusion or not, according to institutional and individual practice, without random assignment.

MEASUREMENTS AND RESULTS

The independent effect of SMB transfusion on postoperative RBC transfusion was examined by multivariable modeling. Potential complications of SMB transfusion, such as bleeding and infection, were examined. Three hundred twelve of the study patients (51%) received postoperative SMB transfusion (mean volume, 554 +/- 359 mL). Patients transfused with SMB had significantly lower volumes of RBC transfusion than those not receiving SMB (0.86 +/- 1.50 v 1.08 +/- 1.65 units; p < 0.05). However, multivariable analysis showed that SMB transfusion was not predictive of postoperative RBC transfusion. Demographic factors (older age, female sex), institution, and postoperative events (greater chest tube drainage, lower hemoglobin level on arrival to the intensive care unit, and use of inotropes) were significant predictors of RBC transfusion. The volume of chest tube drainage on the operative day (707 +/- 392 v 673 +/- 460 mL; p = 0.30), reoperation for hemorrhage (3.1% v2.5%; p = 0.68), and overall frequency of infection (5.8% v 6.6%; p = 0.81) were similar between patients receiving and not receiving SMB, respectively. However, in patients who did not receive allogenic RBC transfusion, there was a significantly greater frequency of wound infection in the SMB group (3.6% v0%; p = 0.02).

CONCLUSION

These data suggest that SMB is ineffective as a blood conservation method and may be associated with a greater frequency of wound infection.

Pentastarch versus albumin in cardiopulmonary bypass prime: impact on blood loss

BACKGROUND

Albumin is commonly used as a volume expander in cardiopulmonary bypass (CPB) prime. Pentastarch, a low molecular weight hetastarch, may provide similar efficacy at decreased cost but is known to alter coagulation profiles. Infectious concerns forced the temporary withdrawal of albumin in our institution. Therefore we evaluated pentastarch as an alternative with regards to perioperative hemostasis and blood loss.

METHODS

One hundred consecutive adult patients undergoing first-time aorto-coronary bypass were given 750 mL of 10% pentastarch (represented as P in calculations) diluted in 1000 mL of Ringer's solution added in their CPB prime. A similar control group of 100 consecutive patients had received 200 mL of 25% albumin (represented as A in calculations) diluted in 1500 mL of Ringer's solution.

RESULTS

Postoperative prothrombin time (PT) was slightly higher with pentastarch (P: 14.9 +/- 1.5 seconds, A: 14.2 +/- 1.3 seconds, p = 0.003). Postoperative bleeding was also increased (P: 2337 +/- 1242 mL, A: 1981 +/- 1121 mL, p = 0.034), mostly because of recirculated shed mediastinal blood (P: 834 +/- 499 mL, A: 640 +/- 388, p = 0.002) rather than lost pleural tube blood (P: 1503 +/- 821 mL, A: 1341 +/- 824 mL, p = 0.16). Overall net blood loss (P: 2014 +/- 914 mL, A: 2061 +/- 1015, p = 0.73) was similar. Blood-product transfusion requirements and postoperative daily hematocrits did not differ.

CONCLUSION

The diminished coagulability associated with this dose of pentastarch resulted in increased postoperative bleeding. However, with recirculation of shed mediastinal blood, there was no net increase in blood loss. In this setting, pentastarch may serve as a suitable alternative to albumin.

Autotransfusion of washed shed mediastinal fluid decreases the requirement for autologous blood transfusion following cardiac surgery: a prospective randomized trial

OBJECTIVES

The National Blood Service issues 2.2 million units of blood per year, 10% of these (220000) are utilized in cardiac procedures. Transfusion reactions, infection risk and cost should stimulate us to decrease this transfusion rate. We test the efficacy of autotransfusion following surgery in a prospective randomized trial.

METHODS

One hundred and twelve patients undergoing CABG, valve or CABG + valve procedures were randomized into two groups. Group A received washed postoperative drainage fluid and group C were controls. The indication for transfusion was a postoperative haemoglobin (Hb) < 10 g/l or a PCV < 30. There was no significant difference in preoperative and operative variables between the groups.

RESULTS

Twenty-eight patients in group A and 46 in group C required homologous transfusion (P = 0.0008). Group A patients required 298+/-49 ml of banked blood per patient, group C 508+/-49 ml (P = 0.003). There was no difference in total blood required (volume autotransfused + volume banked blood transfused) between the groups (group A 404+/-50 ml, group C 508+/-50 ml) or in mean total mediastinal fluid drainage (group A 652+/-51 ml, group C 686+/-50ml). The mean Hb concentration was significantly higher in group A on day 1 (11.2 g/dl+/-51 vs. 10.6 g/dl+/-13 (P = 0.002)). No morbidity was associated with autotransfusion.

CONCLUSION

Autotransfusion can decrease the amount of homologous blood transfused following cardiac surgery. This represents a benefit to the patient and a decrease in cost to the health service.