Primer on blood salvage: implications for the hospital pharmacist

With a basic understanding of intraoperative and postoperative blood salvage procedures, pharmacists can use their expertise in pharmacology and pharmacokinetics to answer questions regarding drug disposition during blood salvage. The methods and equipment, as well as the indications for its use are described. Pharmacological considerations include the patient's drug regimen, agents used in the surgical field including irrigation solutions, hemostats, and the anticoagulant used in the salvage system. In addition to providing drug information, the pharmacist should be involved in the admixing of the anticoagulant solutions used in the salvage system. A basic bibliography for the subject is provided.

Comparative analysis of recovery of cardiopulmonary bypass residual blood: cell saver vs. hemoconcentrator

For surgical bleeding problems, the cell saver has been used to return shed blood; however, overuse can lead to a deficit in coagulation factors. Its usefulness has gained widespread use in many surgical settings. The hemoconcentrator can aid in raising the hematocrit level while reducing blood utilization where large blood volume and/or large amounts of irrigation are returned to the perfusion circuit. The hemoconcentrator returns red blood cells without removing coagulation factors, unlike the cell saver. In order to determine which method of returning residual blood from the cardiopulmonary bypass circuit is more desirable, blood samples were drawn both pre and post transfusion from 15 cell saver patients, and 14 hemoconcentrator patients. Twelve hour blood loss was recorded in 40 patients within each group. The fibrinogen, platelet count, total protein, albumin and white blood cell count were similar between the two groups, as was the blood loss. The only significant differences found were the post red blood cell count, post hemoglobin, and the delta hematocrit, all being higher in autotransfusion group. In conclusion, returning blood through the hemoconcentrator in the average adult perfusion circuit was not able to significantly raise certain coagulation parameters, nor reduce postoperative bleeding.

A new technique for intraoperative blood recovery in the cancer patient

Homologous blood transfusion in the cancer patient is dangerous because of an apparent immunodepressive action. Even a program of pre-deposit and isovolemic hemodilution, for reasons of immediacy and patient conditions, is often not feasible. Likewise, the intraoperative recovery of blood, although used by some, does not prevent the possible reinfusion of suspended neoplastic cells. A system that eliminates tumor cells could enable the recovery of blood in cancer patients in non-septic operative sites. A system that seems to correspond to these requisites has been set up by inserting two filters for the elimination of leucocytes from erythrocyte concentrates into a cell separator that is normally used in clinical practice. Laboratory studies, using immunohistochemical identification of tumor cells cultivated in vitro, have demonstrated the absence of contaminating cells in blood available for reinfusion.

Effects of cardiopulmonary bypass on lymphocytes and their subset counts with or without use of autotransfusion devices

Lymphocytes and their subset counts were determined in 30 cardiac surgery patients during cardiopulmonary bypass (CPB) with or without use of an autotransfusion device. In the autotransfusion group, centrifuged and washed autologous red blood cells (median 400 mL [range 200-770 mL]) and in the control group corresponding amounts of homologous packed red blood cells (median 500 mL [range 250-750 mL]) were transfused after declamping the aorta. The percentages of T lymphocytes (CD3) and T cytotoxic cells (CD8) increased in both groups (CD3 up to 5%, P < 0.05 and CD8 up to 35%, P < 0.01), but the percentage of T helper cells (CD4) did not change. The ratio of CD4/CD8 cells decreased (up to 34%, P < 0.01). The percentage of naive resting T cells (CD45RA) increased slightly (up to 8%, P < 0.05) whereas the percentages of memory T cells (CD45RO), T cells with IL-2 receptor (CD25), and natural killer cells (CD16) remained unaltered. The percentage of HLA-DR positive lymphocytes increased during CPB (up to 18%, P < 0.05), but it was decreased thereafter (up to 16%, P < 0.05). The percentage of monocytes (CD14) decreased first during CPB in both groups (up to 32%, P < 0.01), but it was higher in the autotransfusion device group (decreased 29% from initial value) than in the control group (decreased 65% from initial value) at the end of CPB (P < 0.05). This study shows that extracorporeal circulation has an effect on lymphocytes and their subset counts. The changes were slightly immunosuppressive. By contrast, use of autotransfusion devices had only minor effects.

Quality of washed salvaged red blood cells during total hip replacement: a comparison between the use of heparin and citrate as anticoagulants

A randomized, prospective study comparing heparin with citrate (ACD) as anticoagulant during red blood cell saving was performed in 10 ASA grade I-II patients undergoing primary total hip replacement. Blood samples were taken before and after surgery and at several steps during cell saving. In the heparin group, salvaged red cells showed normal values, with the exception of decreased filtrability and moderate hemolysis. More differences in red cell quality were found in the ACD group. Mean corpuscular volume was higher (110 vs 95 x 10(-12) mL), red cell distribution was increased (17% vs 13%), osmotic resistance was lower (0.54 vs 0.43 g NaCl/L at 50% hemolysis), antioxidative reserve capacity was lower (1.9 vs 4.6 U glutathione reductase per gram of hemoglobin) and there was more hemolysis (15% vs 11%). Despite the small volume of autologous blood retransfused (388 +/- 92 mL), the differences in vitro produced significantly higher free hemoglobin levels in the patients' plasma at the end of the operation (58 vs 23 mg/dL). We conclude that heparin is preferable to citrate as an anticoagulant during autotransfusion with cell washing and immediate retransfusion.

[Bacterial infection within the scope of hemotherapy]

OBJECTIVE

The purpose of this article is to present a survey of bacterial infections caused by hemotherapy.

DATA SOURCES

Original papers as well as review articles from international investigations based on literature data banks.

RESULTS

As there exist only a few studies about transfusion complications caused by bacteria you only can find sporadic reports. Surely immunocompromised recipients have high risk to be hurt. Causing bacteria are various but Staphylococci, Yersinia, Serratia and Pseudomonas species often are found. Especially platelet concentrates give higher infection risk because storage at room temperature is obligatory. This fact makes growth conditions more comfortable. Strict hygienic measures, extension of donor screening and pointed quality control are capable to decrease the risk of transfusion complications.

CONCLUSIONS

Exact indications and a clear strategy evaluating the transfusion reports and routine bacteriological control are necessary to prevent infections caused by hemotherapy.

Experience of autologous blood transfusion at a district general hospital in Zambia

An Autologous Blood Transfusion Programme has been in operation at Ndola Central Hospital (NCH) since April 1992. This paper describes a method of cell salvage and reviews the two types of autologous transfusion [acute isovolaemic haemodilution (AIH) and cell salvage] practised over the 6 month period November 1992 to April 1993. No complications or adverse effects were encountered and the benefits include reduction of immunological reactions and transmission of infection, which are risks associated with homologous transfusion. There is need to minimize homologous transfusions because of these risks and hospitals should develop reasonable, practical guidelines for safer transfusion, including the use of autologous blood whenever possible.

The basic concepts of an autotransfusor: the Cell-Saver

The basic concepts in the technology and techniques have been presented. Other articles in this issue discuss in more detail the physiological considerations of autotransfused RBCs as well as the efficiency of the Cell-Saver from the standpoint of a hematologic evaluation.

Perioperative interventions to decrease transfusion of allogeneic blood products

OBJECTIVE

To discuss some of the many options available for decreasing perioperative transfusion of allogeneic blood products.

DESIGN

We review the issues that focus on the goal of developing an appropriate transfusion strategy in consideration of the individual patient's preexisting conditions, physiologic requirements, perioperative stress, and coagulation status.

RESULTS

Increased awareness of transfusion-related morbidity from allogeneic blood products has resulted in increased development and application of alternatives to allogeneic transfusion. Preoperative donation and perioperative collection of autologous blood and blood products decrease exposure to allogeneic blood. Pharmacologic agents, such as antifibrinolytics, may also decrease the need for allogeneic transfusion. Perioperative use of laboratory tests of coagulation function facilitates the rapid and specific diagnosis of coagulation disorders.

CONCLUSION

Physicians now have considerable appreciation of the risks and benefits of blood product transfusion. This knowledge has resulted in conservative and scientific approaches to therapy for perioperative bleeding and coagulopathy.

Postoperative salvage: a technological advance in the 'washed' versus 'unwashed' blood controversy

AT techniques are becoming the standard of care in surgery. Some controversy exists regarding the use of washed versus unwashed salvaged blood, as discussed. The literature concerning this unresolved problem has been reviewed. Because blood collected intraoperatively has undergone clotting and lysis, no beneficial coagulation effects can be expected with reinfusion of unwashed blood. If, additionally, potentially harmful effects may result, a strong argument can be made for washing the RBCs free of the activated clotting factors before reinfusion. Theoretically, this has strong appeal. In practice, it is recognized that patients who are in good health can tolerate small volume reinfusion of unwashed blood, particularly if they have been anticoagulated. In weighing the options and the risk/benefits equation, it would appear that washing the RBCs is generally the safest course. Now, it seems that there is a definite trend toward washing the red cells before reinfusion. Technological advances make this possible. The Haemolite 2 is a small, compact, portable autotransfusor that provides a safe, practical, and efficient means of recycling the patients own blood in the postoperative salvage setting.

[Clinical experience of autotransfusion of shed mediastinal blood using a new device]

Autotransfusion of shed mediastinal blood is expected to be adopted as a technique to reduce transfusion thus preventing various complications such as hepatitis, AIDS, and GVHD. We report the usefulness and problems of a new device-Solcotrans Plus, which only requires connection to wall suction. This device consists of three parts: suction, reservoir bag, and filter for autoinfusion. After setting the suction and reservoir bag primed with anticoagulant, ACD or heparin, and connecting the unit to a wall suction, we performed autotransfusion of shed blood through the filtration component in ICU after operation. Postoperative hematological and biochemical examinations revealed no complications or adverse effects of autotransfusion. This device is available, simple to handle, and is useful for returning shed blood. We believe that this device will be effective for non-blood open heart surgery or reduction of transfusion.

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.

[Autologous fibrin glue from concentrated platelet rich plasma: intraoperative plasma sequestration using autotransfusion device]

Making autologous fibrin glue from intraoperatively collected concentrated platelet rich plasma (C-PRP) was attempted in 5 patients who underwent elective coronary artery bypass. The autologous blood was withdrawn from the patient before cardiopulmonary bypass and sequestrated for C-PRP, concentrated red cells (CRC) and platelet poor plasma (PPP) using an Electromedics Elmd-500 autotransfusion device. CRC and PPP were returned intravenously to the patient as needed intraoperatively or postoperatively. Aprotinin was dissolved in C-PRP to yield a concentration of 1000U/ml to the aim of suppressing the plasmin activity. In another syringe, thrombin was dissolved in 2% calcium chloride solution to 1000U/ml. The C-PRP/aprotinin was mixed in ratios of 20:1, 10:1, 5:1, 3:1 to the thrombin/C a++ solution and observed the time for clotting. The 10:1 and 5:1 mixture usually clotted within 3-5 seconds, whereas it was necessary 5 or more seconds in other ratios. Therefore we used in the ratio of 5:1 for all patients. The fibrin glue from this technique is little different from the fibrin glue on the market in its viscosity, and has some major advantages 1. large amount of glue is available 2. simple and inexpensive 3. eliminate the risk of side effect such as virus transmission.

Complications of autotransfusion with salvaged blood

As a means of limiting homologous transfusions, many centers are using autotransfusion devices during the postoperative period. Although their use may limit the risks associated with homologous blood administration, various adverse effects have been reported including sepsis, disseminated intravascular coagulation, and renal insufficiency. The authors present the case of a 9-year-old girl who developed acute cardiorespiratory dysfunction after reinfusion of salvaged blood. The use of autotransfusion devices and the probable mechanisms responsible for adverse effects are discussed.

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 m2), and from Dideco (n = 9) consisting of a hard shell reservoir with a filter having a larger contact area (4.64 m2). 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.(ABSTRACT TRUNCATED AT 250 WORDS)

Haematological effects of postoperative autotransfusion in spinal surgery

A prospective, randomized, controlled study was performed to determine the haematological and biochemical changes and clinical safety of postoperative autotransfusion (Solcotrans Orthopedic Plus system) in patients undergoing spinal surgery. Fifty patients were studied and were randomly allocated to Control (n = 25) and Solcotrans (n = 25) groups. Both groups had their postoperatively drained blood collected into the Solcotrans reservoir but only the Solcotrans group had this salvaged blood considered for reinfusion. After a 5-h postoperative collection period, analysis of the shed blood showed a haematocrit of 0.26 +/- 0.11, few platelets (80 +/- 63 10g.l-1), a fibrinogen level of less than 0.1 g.l-1 and a high level of D-dimers. The salvaged blood did not clot and aerobic and anaerobic culture produced no growth. The volume of blood collected was greater than 200 ml in 21 patients in the Solcotrans group who were autotransfused (384 +/- 101 ml, range 200-600 ml), and in 16 patients in the Control group. Within 15 min following completion of reinfusion of the salvaged blood there was a significant, but moderate decrease in platelet count (181 +/- 74 vs 223 +/- 90 10g.l-1, P < 0.001) and fibrinogen concentrations (2.1 +/- 0.8 vs 2.3 +/- 0.9 g.l-1, P < 0.02), and an increase in circulating D-dimers (P < 0.001) and plasma free haemoglobin concentrations (236 +/- 155 vs 82 +/- 79 mg.l-1, P < 0.001). Prothrombin time (PT) and activated partial thromboplastin time (APTT) did not increase, and potassium concentrations were not significantly affected.(ABSTRACT TRUNCATED AT 250 WORDS)

[Experience in the use of autotransfusions of laser-irradiated blood in treating hypertension patients]

Autotransfusion of laser light-irradiated blood (5-7 sessions) was found to facilitate a steady arterial blood pressure fall by an average 24% of the initial level in patients with hypertensive disease. Drop in the arterial blood pressure following the course of autotransfusion of laser light-irradiated blood was accompanied by improvement in general condition of the patients, enhancement of the effectiveness of antihypertensive preparations, favourable shifts in immunological and haemorheological indices. After discharge from hospital beneficial clinical effect persisted for up to 4-8 months. The preliminary data obtained suggest that autotransfusion of laser light-irradiated blood may well be used as adjunct to a complex of therapeutic measures to be taken to control hypertensive disease.

Intraoperative whole blood autotransfusion during venous thrombectomy

OBJECTIVE

Intraoperative autotransfusion is currently performed using two different systems, the relatively expensive cell-saving device washes and concentrates red cells and the more simple, economical total disposable device for whole blood collection and retransfusion. Some institutions prefer the cell-saving device because of previously documented side-effects of whole blood autotransfusion. As some investigators more recently reported the application of whole blood autotransfusion without clinical complications, the potential hazards of whole blood autotransfusion are now being controversially discussed.

MATERIALS AND METHODS

The potential side-effects using whole blood autotransfusion were studied in 100 patients prospectively undergoing venous thrombectomy. The effectiveness of homologous transfusion reduction was assessed in comparison with an historical patient group (n = 10, control group).

RESULTS

In the study population a mean of 1064 ml shed blood (67% of total blood loss) was retransfused. A mean of 247 +/- 292 ml of homologous blood was transfused in the study group. In contrast, homologous blood requirement was significantly higher (1056 +/- 659 ml, p < 0.006) in the control group. No hematologic, hemeostatic, renal or pulmonary complications occurred after intraoperative whole blood autotransfusion.

CONCLUSIONS

Whole blood autotransfusion is a safe, easy and economical procedure and highly effective in reducing homologous blood transfusions and costs.

Extracorporeal circulation as a blood conservation technique for extensive pelvic operations

Difficult pelvic operations for malignancy or complex benign conditions can be associated with extensive blood loss. Religious beliefs that preclude transfusion and the known risks of homologous blood have prompted investigators to seek alternatives to transfusion. We used the Haemonetics-V50 Cell Separator (Haemonetics Corporation) to provide for extracorporeal circulation of the patient's own blood with associated normovolemic hemodilution as a means of conserving blood during operations. This technique was used in eight patients undergoing extensive pelvic operations. The procedure was accepted by Jehovah's Witnesses and was well tolerated by all patients. Estimated blood loss ranged from 75 to 2,000 milliliters. One instance of mild intraoperative disseminated intravascular coagulation was encountered. Two patients were given homologous transfusions. While clinical judgment is necessary to determine the safety of complicated operations, this technique is useful in expanding surgical options for some patients who object to blood transfusion.

Removal of Avitene microfibrillar collagen hemostat by use of suitable transfusion filters

We assessed the ability of two commercial filters (Pall RC100 and Statlabs 20 microns) to filter out Avitene microfibrillar collagen hemostat from suspension. Quantitative determination of the collagen content as well as scanning electron and light microscopy, particle counting, and platelet aggregometry of filtrates revealed that these filters effectively remove potentially thrombogenic particles of Avitene microfibrillar collagen hemostat. The filters removed at least 97% of the total collagen, as determined by hydroxyproline analysis. The collagen that passed through the Pall filter did not pellet upon ultracentrifugation. Scanning electron and light microscopic analysis revealed no Avitene microfibrillar collagen hemostat particulates in the Pall filtrates but did reveal the presence of a significant number of approximately 1- to 8-microns particulates in the Statlabs filtrates. Concentrates of the filtrates from either of the two filters, however, did not promote platelet aggregation. Through ultracentrifugation and infrared analysis, the filtrates were found to consists of soluble, partially denatured collagen. The risk associated with the reintroduction of collagen particulates into the vasculature can be significantly reduced by use of appropriate, currently available blood-transfusion filters.

Autologous blood transfusion: why and how

Although first reported more than 100 years ago, autologous blood transfusion was grossly underused until the 1980s, when the safety of blood came into question. With the discovery of transfusion-transmitted human immunodeficiency virus (HIV), physicians and patients began to request this form of transfusion. In this article, four modalities of autologous transfusion are described: preoperative blood donation, acute normovolemic hemodilution, intraoperative blood recovery, and postoperative blood salvage. The indications and contraindications for the use of these modalities, patient eligibility, and the blood center's involvement in these services also are explained.