Autotransfusion System Research Articles

Fat elimination during intraoperative autotransfusion: an in vitro investigation.

Intraoperative autotransfusion of scavenged blood is an established method to reduce the need for perioperative homologous blood transfusion. However, if fat particles contaminate blood suctioned from the wound site, no reliable method is available to remove them during the washing and concentration of the recycled blood. A new generation of autotransfusion devices (e.g., continuous autotransfusion system [CATS]), based on separation chambers used in cell separators or plasmapheresis devices, allows continuous procession of the collected blood, in contrast with the discontinuous process used in conventional autotransfusion devices such as the Cell Saver 5. Theoretically, the continuous system should be more efficient than the discontinuous system in eliminating fat. Outdated, 36-day-old packed red blood cells, 600 mL, were mixed with 500 mL of lactated Ringer's solution and 200 mL of soya oil. Soya oil was used because it has a fatty acid composition similar to that of fat found in bone marrow. The blood mixture was then washed and concentrated by using either the CATS or the Cell Saver 5. Six samples were processed by each device. The CATS eliminated the soya oil (200 mL) completely, whereas the Cell Saver 5 delivered 30.3 +/- 7.8 mL soya oil into the retransfusion bag. The new generation of autotransfusion devices allows complete removal of fat particles. Autotransfusion devices serve to wash and retransfuse blood scavenged from the wound site. However, they cannot completely remove fat particles. This in vitro investigation showed that a new device completely removes fat particles and thus prevents retransfusion of fat.

Autotransfusion after total knee arthroplasty: Effects on blood cells, plasma chemistry and whole blood rheology

Postoperative drain blood was collected and reinfused using the ConstaVac system (Stryker, Kalamazoo, MI) in 30 patients after total knee arthroplasty. Of the total 1.1-L volume of postoperative bleeding, 60% was reinfused. No clinical complications were observed. Differences between venous blood and drain blood and between venous blood and drain blood after separate incubation were studied with respect to acidic and inflammatory effects on blood cells, plasma chemistry, and whole blood rheology. In drain blood, leukocyte and platelet counts were reduced ( P < .001), probably as a result of consumption in the wound. Acidic incubation occurs in the drain container because of production of lactate from glucose, with a minimum pH at 5 hours of 7.2. The low pH caused slight but significant erythrocyte swelling ( P < .01). The complement C3d indicated leukocyte activation, although of modest magnitude. Despite incubation and complement activation, maximum erythrocyte hemolysis after 24 hours of incubation was less than 1%. Drain blood showed a lower resistance against micropore filtration than venous blood ( P < .001), mainly because of the reduced number of leukocytes, and remained unchanged with incubation. Although the autotransfusion system can be improved with respect to blood quality, filtered drain blood should be considered acceptable for reinfusion.

Effects on complement activation of a new continuous autotransfusion system.

Allogeneic blood transfusions may subject patients to risks of infection and allergic reactions. Various techniques for transfusion of shed blood have been developed. The aim of this study was to evaluate a new continuous autotransfusion system (Fresenius CATS) as regards its impact on the complement system, and on erythrocytes and leucocytes. Eighteen consecutive patients undergoing hip replacement surgery were studied. Complement variables (C4d, factor Bb, C3a and terminal complement complex, SC5b-9) and free haemoglobin, haemoglobin, leucocytes, platelets, albumin and protein were determined in the patient's blood preoperatively, 1 min before the start of transfusion, 15 and 60 min after transfusion; and in the reservoir, in the waste bag and in the retransfusion blood. Increased concentrations of C3a and SC5b-9 were found in the collected reservoir blood (P < 0.05). The washing and centrifugation procedure reduced these concentrations (< 0.001). High levels of free haemoglobin were found in the collected blood as well as in the processed product. The median haemoglobin level in the processed blood was 260gL-1 (range 104-289gL-1). Inflammatory mediators from the complement cascade are removed by continuous autotransfusion technique. The processed blood contains high levels of free haemoglobin.

Qualitative Assessment of Blood Washing with the Continuous Autologous Transfusion System (CATS)

A number of different blood-processing methods can be used at the end of cardiopulmonary bypass (CPB) to improve the quality of autologous blood. They include centrifugation, hemofiltration and cell-washing. They differ in processing time required, cost of disposables and the quality of the processed autologous blood product. The newly developed continuous auto-transfusion system (CATS: Fresenius AG, Bad Homburg) uses a continuous cell-washing method. In a prospective study, the oxygenator blood of 10 patients was processed at the end of cardiac surgery with CATS and the quality of autologous blood before and after processing was compared. The processing volumes and the time required were recorded. The concentrations and elimination rates of blood parameters and waste products such as activated coagulation and complement products were measured. At the end of CPB a mean volume of 1,010 +/- 174 ml diluted oxygenator blood was processed and concentrated to 310 +/- 88 ml in 11.0 +/- 2.2 mins. Cellular elements such as erythrocytes and leucocytes were mostly retained and their concentration showed a significant increase after processing (250% and 210% respectively; p < 0.01). Thus, the blood processing with CATS resulted in an excellent hemoconcentration (hematocrit 62 +/- 3 vs. 24 +/- 4% before processing) with a consistent reproducibility. On the other hand, the CATS concentrate showed a significant loss of autologous plasma proteins. Likewise, all water soluble elements such as waste products are significantly lower in concentration after processing and, if calculated by quantity, they show a high elimination rate (> 93%). In conclusion, the continuous autologous transfusion system permits an automated, rapid and continuous processing of autologous blood yielding a standardised high quality erythrocyte concentrate.

Blood salvage after total hip and total knee arthroplasty.

We performed a prospective study to determine the effect of postoperative collection and reinfusion of unwashed, filtered, salvaged blood alone and in combination with preoperative predeposited blood on the transfusion requirements of 375 patients treated with a total hip or total knee replacement. 208 patients were managed with postoperative blood salvage with use of the CBC ConstaVac autotransfusion system and closed suction drainage. Another 50 patients predeposited 1-4 units of autologous blood, before the operation, in addition to postoperative blood salvage. The remaining 117 patients were used as controls and were transfused with homologous blood from the blood bank. Postoperative reinfusion of salvaged blood decreased the need for homologous transfusion after hip and knee arthroplasty (mean 2.7 units) compared to controls (mean 4.2 units). The combination of postoperative reinfusion of salvaged blood and predeposited autologous blood was associated with the lowest requirements for homologous blood transfusions (mean 1.7 units).

The quality of autotransfused chest-drainage blood after cardiac surgery: a study of coagulation factors.

A wide range of experience, dating back as far as 1978, has been gained with both the hard-shell cardiotomy reservoir of the heart-lung machine and the Sorensen autotransfusion system as retransfusion systems. Three remains, however, a lack of knowledge regarding the quality of retransfused blood in systems of less complex construction which are already available on the market and involve the use of a pouch (Sentinel-Seal autotransfusion system and Pleur-evac collecting system). The present study entailed the investigation of blood from the chest drainages of twenty patients after cardiac surgery by using a simple retransfusion system (Sentinel-Seal autotransfusion system). In two postoperative groups of patients with low and high blood loss from chest drainage, we determined, in addition to free plasma hemoglobin, the following: factor XII, kallikrein-like activity, thrombin-antithrombin III complex, tissue-plasminogen and d-dimers. In the collective with a low blood loss, we found remarkable cell alterations as well as highly activated and advanced coagulation and an extraordinary fibrinolytic activity. If done at all, retransfusion by the Sentinel-Seal autotransfusion system should be restricted to the first four postoperative hours in cases of high blood loss.

Impact of transfusion of mediastinal shed blood on serum levels of cardiac enzymes

Infusion of shed mediastinal blood using an autotransfusion system is a widely applied technique of blood conservation in cardiac surgery. Serial determinations of serum creatine kinase (CK), its MB isoenzyme (CK-MB), and lactate hydrogenase (LDH) levels have been used to monitor perioperative myocardial injury. We investigated the impact of postoperative autotransfused blood infusion on serum levels of these enzymes. We performed a retrospective analysis of postoperative serum CK, CK-MB, and LDH levels of 300 patients who had elective uncomplicated aortocoronary bypass grafting. Shed mediastinal blood samples from 26 patients were analyzed for CK, CK-MB (enzymatic activity and mass), and LDH levels before infusion. High postoperative serum levels of CK and LDH were observed after infusion of autotransfused blood. Shed mediastinal blood contained extremely high levels of these enzymes, particularly from patients who had internal mammary artery dissection. There was a strong correlation (r = 0.96) between measured CK-MB enzyme activities and those calculated from the CK-MB mass units. Infusion of autotransfused blood containing high concentrations of CK and LDH results in elevated serum levels of these enzymes. Hemolysis, frequently present in shed blood, does not interfere with the routine biochemical assays for CK and CK-MB enzyme activities. Caution should be taken when postoperative cardiac enzyme levels are used to determine myocardial injury after aortocoronary bypass grafting if autotransfusion is used as a method of blood conservation.

Survival of autotransfused red cells. 51Cr studies in 10 knee arthroplasty patients.

We determined the long-term survival of red blood cells collected postoperatively from the surgical drains, filtered and autotransfused with the Constavac Blood Conservation System. 10 patients with knee arthrosis were treated with cementless total knee arthroplasty and postoperatively connected to the autotransfusion system. Shed blood was collected for 6 hours postoperatively and then reinfused. Before reinfusion, a fraction of the blood shed was radiolabeled with chromium-51 (51Cr). For a postoperative minimum period of 40 days the activity of 51Cr was measured in frequent venous blood samples. The time from 100% to 50% activity of the isotope (T50Cr) was 21 days, equal to that reported for banked autologous blood.

A Modified Collection and Rapid Infusion System for Shed Whole Blood Autotransfusion During Aortic Aneurysm Surgery

We describe our experience in 10 patients (5 males) undergoing resection of a descending thoracic aortic aneurysm or a thoracoabdominal aortic aneurysm in which a modified shed whole blood collection and autotransfusion system was used. This modification allows several options for the processing and autotransfusion of shed blood: use of the cell saving device or the ultrafiltration of collected blood, and the autotransfusion of unprocessed shed whole blood. Either low dose heparin or sodium citrate was used for anticoagulation. All 10 patients underwent autotransfusion and volume resuscitation with the modified rapid infusion device. Total autotransfusion ranged from 1400 ml to 7843 ml. Ultrafiltration volumes ranged from 600 ml to 1100 ml. There were no intraoperative deaths and no patient reoperations for bleeding. Arterial blood gases, potassium, and platelet counts were all within the normal laboratory ranges. This modification enables the clinician to process poor quality shed blood and reinfuse whole blood, in an attempt to decrease the need for homologous blood products.

Postoperative blood salvage in total knee arthroplasty using the Solcotrans autotransfusion system

One hundred forty-four patients who underwent primary total knee arthroplasty were examined in a prospective controlled study to determine the efficacy and safety of a postoperative wound drainage autotransfusion system (Solcotrans, Smith & Nephew Richards, Memphis, TN). The patients were divided into two groups: control group 1 comprised 88 (61%) patients who either received a Hemovac disposable drainage system (63 patients) or the Solcotrans system and had inadequate drainage for autotransfusion (25 patients). Experimental group 2 comprised 56 (39%) patients who received a Solcotrans drainage system and were autotransfused. The Solcotrans proved itself safe. No sepsis, transfusion reactions, or coagulopathies were associated with autotransfusion, which averaged 524 mL. There were no significant differences between groups 1 and 2 when comparing preoperative and postoperative hemoglobins and hematocrits. The Solcotrans system did not lower homologous blood requirements. Only 1.6% (2 patients) of all patients who autodonated at least 2 units of autologous blood (122 patients) were in need of a homologous blood transfusion in the postoperative period. Thus, although safe, the Solcotrans system was not proven effective in the management of primary total knee arthroplasty patients.

Con: Shed mediastinal blood should not be reinfused after cardiac surgery

HE PREVENTION and treatment of postoperative bleeding after cardiac surgery are important both to reduce perioperative complications and to reduce the exposure of panents to homologous blood products. Postoperative reinfusion of shed mediastinal blood is one of a large array of interventions that have been studied to achieve these goals. In this technique, blood is collected from the chest tubes Into a reservoir under gentle suction and then retransfused into the patient after being passed through a filter. The average retransfuslon volume as approximately 400 to 500 mL but may range from a few hundred milliliters to several hters. The routine use of postoperative autotransfuslon was advocated by Schaff and colleagues x.2 They randomized 114 adult cardiac surgical patients to receive either retransfusion of shed medmstinal blood using a Sorenson autotransfusion system (Sorenson Research Corp., Salt Lake City, UT) or homologous blood only (control group). Total postoperative blood loss and total blood replacement were similar between the two groups, but the autotransfusion group received sigmficantly less banked blood (2.4 _+ 0.3 units v 4.8 - 0.6 units for the control group). They also reported data with the routine use of reinfusion of shed mediastinal blood m 700 adult and pediatric patients. 2 They suggested that autotransfusion reduced the need for postoperative homologous blood transfusions by 50% compared with a historical control group from 2 years previously. However, other studies have failed to demonstrate benefit with postoperative autotransfusion. 3-8 Thurer et al performed a randomazed prospective study of autotransfusion in 113 patients in whom additional techniques also were used to reduce the requirement for homologous transfusion? These techmques included intraoperatwe blood withdrawal and retransfusion after cardiopulmonary bypass (CPB), normovolemic hemodilution, intraoperatlve retransfusion of shed blood, and meticulous surgical hemostasis Use of these techniques alone had reduced their average blood product usage from 8 units per paUent in 1972 to 2.5 units an 1978. The investigators found no statistical difference in postoperatwe chest tube drainage, the number of patients requiring homologous blood, and average blood product replacement or hematocrit at any time postoperatively between patients who had postoperative autotransfusion and those who did not 9 Similarly, subgroup analysis of pataents wath large blood loss ( > 25 mL/kg) also showed no dafference in saving of banked blood in the autotransfusaon

Shed whole blood autotransfusion during aortic aneurysm operation with a modified collection infusion system

We describe a modified shed whole blood collection and autotransfusion system that allows several options for the processing and autotransfusion of shed blood: use of the Cell Saver (Haemonetics, Braintree, MA) or the ultrafiltration of collected blood, and the autotransfusion of unprocessed shed whole blood. The system has proved useful for transfusion in the setting of thoracic aortic operations, and we describe here our experience in 5 patients undergoing resection of a descending thoracic aortic aneurysm in whom this system was used.

Clinical Results with a New Continuous Autotransfusion System (C.A.T.S ®, Fresenius AG)

Die Qualität des im «Quality Wash»-Programm des kontinuierlich arbeitenden Autotransfusionsgerätes C.A.T.S® (Fresenius AG) produzierten autologen ge-waschenen Erythrozytenkonzentrates (AGEK) wurde in dieser Studie an 15 Fallen groβer orthopädischer Operationen untersucht. Es ergaben sich gleichmäβig hohe (68+3%) Hämatokritwerte, die vom Volumen des AGEK und von Volumen und Zusammensetzung des intra- und postoperativen Sammelblutes unabhängig waren. Die biochemischen Parameter, die im AGEK gemessen wurden, unterstreichen dessen gute Qualität ebenso wie das während der Aufbereitung im Disposable zurückgehaltene Fett.

The Efficiency of an Autotransfusion System for Tumor Cell Removal from Blood Salvaged During Cancer Surgery

The efficiency of a gravity-dependent autotransfusion system (ATS) for filtering tumor cells from blood was examined under laboratory and clinical conditions. In laboratory studies, reconstituted whole blood was seeded with known numbers of cultured A431 human vulva carcinoma cells then filtered through the ATS. Cancer cells were recovered from blood samples taken before and after filtration using a density gradient centrifugation procedure, and identified by immunocytochemical techniques, based upon their cytoskeletal intermediate filament proteins. It was estimated that 55%-76% of the A431 cells were retained by the ATS filters, and of those cancer cells that passed through the ATS, 62% suffered lethal trauma and the remainder showed morphologic damage. In clinical studies, blood was harvested from the surgical site during resection of primary cancers from three patients. In agreement with the laboratory studies, 50%-68% of tumor cells were filtered by the ATS from blood harvested during surgery. These results are discussed in terms of metastatic inefficiency and the potential for use of autotransfused blood salvaged during cancer surgery.

Systemic blood activation during and after autotransfusion

To evaluate the extent of shed blood activation in two autotransfusion systems and the effect of circulating blood activation upon autotransfusion, we performed a prospective study in 18 patients undergoing internal mammary artery bypass operation and a control group of 10 patients. The autotransfusion systems were from Sorin (n = 9) consisting of a hard shell reservoir with a filter having a small contact area (0.32 m 2), and from Dideco (n = 9) consisting of a hard shell reservoir with a filter having a larger contact area (4.64 m 2). We found high concentrations of thromboxane, fibrinogen degradation products, complement split product C3a, and elastase in the shed blood and, with the exception of C3a, in the circulating blood of autotransfused patients. There was no such activation in control patients. The degree of the systemic inflammatory reaction was determined by the type of autotransfusion system and by the amount of infused shed blood. The Dideco system provoked more inflammatory response than did the Sorin. This was reflected by the larger shed blood loss during autotransfusion in the Dideco patients than in Sorin patients, resulting in infusion of more shed blood (means, 737 mL versus 566 mL; not significant). After autotransfusion, Dideco patients shed significantly more blood than did Sorin or control patients P < 0.05). Dideco patients also needed more colloid/crystalloid solution per 24 hours than Sorin patients ( p < 0.05). This became clinically relevant only after infusion of more than 800 mL of shed blood ( p < 0.001): hemodilution indicated the need for packed cells in 4 Dideco patients and in 1 Sorin patient. Dideco patients required a similar amount of blood products (0.8 ± 0.4 unit) to the control patients. In contrast, Sorin patients required a mean of 0.2 ± 0.2 unit, whereas blood products were avoided in 89% of them, versus 42% of the Dideco and control patients (not significant). In summary, we recommend autotransfusion of a limited amount (less than 800 mL) of shed blood with a reservoir that has the smallest possible contact area. Infusion of more than 800 mL of shed blood provokes derangement of hemostasis and hemodynamics by deleterious systemic blood activation, nullifying blood saving by autotransfusion.

Role of autogenous tissue factors in hemolysis during cardiopulmonary bypass operations

Pericardial fluid has been implicated as a causative factor in hemolysis during cardiopulmonary bypass operations. Preoperative blood samples were obtained from 10 patients undergoing coronary artery bypass grafting for ischemic myocardial disease. Whole blood samples were separately incubated with autogenous pericardial fluid, pericardium, pleura, vein, skeletal muscle, and fat harvested during the operative intervention. The plasma fraction was separated by centrifugation and assayed for serum free hemoglobin. Statistical analysis was accomplished by the Bonferroni technique to adjust for multiple comparisons. Pericardial fluid-induced hemolysis was least (20.7 mg/dL). Pleura and muscle contributed significantly to the serum free hemoglobin level (56.3 and 112.3 mg/dL, respectively; p < 0.05). Pericardium, vein, and fat did not cause significant elevations of the serum free hemoglobin level. Postbypass hemolysis is an important management consideration that may be minimized by delicate tissue manipulation and attention to minimizing tissue trauma. Avoidance of aspiration of pericardial fluid into the autotransfusion system is not supported.

自家血回収システムの有用性

自家血回収システムの有用性

Intraoperative autologous blood salvage with cardiac surgery: An analysis of five years' experience in more than 3,000 patients

Study Objective: To analyze intraoperative autologous salvage of shed mediastinal blood and subsequent transfusion in cardiac surgery. Design: Retrospective statistical analysis. Setting: University hospital. Patients: Three thousand twenty two patients undergoing cardiac surgery from 1984 to 1988. Interventions: A review of anesthesia and transfusion records of all patients who underwent intraoperative salvage of shed blood and autologous transfusion using the Sorenson Receptal Auto Transfusion System (ATS) with saline wash prior to reinfusion in cardiac surgery. Measurements and Main Results: The salvaged blood volume ranged from 36 to 2,795 ml, with a mean of 321 ± 222 ml (SD). Eighteen percent of patients did not receive any homologous blood products during their hospitalization. Patients who received only salvaged autologous transfusion were younger, had higher preoperative hemoglobin and hematocrit values, had a larger body surface area, and had shorter surgeries compared with patients who received only homologous blood or both autologous and homologous blood. More blood products were given to patients who received salvaged autologous blood compared with those who did not. Patients who underwent normovolemic hemodilution prior to extracorporeal circulation with subsequent reinfusion received significantly fewer blood products. Ten preoperative and, four intraoperative variables significantly influenced the salvaged volume. Previous cardiac surgery was the most significant preoperative variable, and repair of ventricular septal defect produced by myocardial ischemia was the most significant intraoperative variable. Conclusion: Considering the average salvaged volume and its current autologous transfusion-related expense, autologous blood salvage is potentially an economic benefit. Perioperative blood conservation requires a considerable commitment from surgeons, anesthesiologists, perfusionists, and intensive care physicians to be effective.

Intraoperative Autotransfusion in Reconstructive Hip Joint Surgery of Patients with Rheumatoid Arthritis and Ankylosing Spondylitis

The efficacy of a simple, low-cost device designed for intraoperative blood salvage and reinfusion, known as the Sorensen system, was studied during 24 hip joint operations in adult patients suffering from rheumatoid arthritis or ankylosing spondylitis. The total need for homologous blood was reduced to 28%, compared with a matched control group of patients who had previously undergone hip surgery by homologous blood replacement. In primary hip-replacement operations, the need for blood was met either completely by autotransfused blood or by the addition of 1 or 2 units of homologous blood. In revision arthroplasties, the maximal need for homologous blood was 6 units owing to a greater blood loss during operation. Postoperative changes in several hematologic variables measured were all very small. The autotransfusion system proved easy and safe to operate. No patients manifested complications. In our experience, the system may be considered an underutilized resource in rheumatological surgery.

後腹膜法と自己血回収システムの組合せによる腹部大動脈りゅう手術

後腹膜法と自己血回収システムの組合せによる腹部大動脈りゅう手術