Intraoperative blood salvage (IOS), also known as cell salvage, is a specific type of autologous blood transfusion. Specifically IOS is a
medical
Medicine is the science and practice of caring for a patient, managing the diagnosis, prognosis, prevention, treatment, palliation of their injury or disease, and promoting their health. Medicine encompasses a variety of health care practic ...
procedure involving recovering blood lost during
surgery
Surgery ''cheirourgikē'' (composed of χείρ, "hand", and ἔργον, "work"), via la, chirurgiae, meaning "hand work". is a medical specialty that uses operative manual and instrumental techniques on a person to investigate or treat a pat ...
and re-infusing it into the patient. It is a major form of
autotransfusion
Autotransfusion is a process wherein a person receives their own blood for a transfusion, instead of banked allogenic (separate-donor) blood. There are two main kinds of autotransfusion: Blood can be autologously "pre-donated" (termed so despite ...
.
It has been used for many years and gained greater attention over time as risks associated with allogenic (separate-donor)
blood transfusion
Blood transfusion is the process of transferring blood products into a person's circulation intravenously. Transfusions are used for various medical conditions to replace lost components of the blood. Early transfusions used whole blood, but mo ...
have seen greater
publicity
In marketing, publicity is the public visibility or awareness for any product, service, person or organization (company, charity, etc.). It may also refer to the movement of information from its source to the general public, often (but not always) ...
and become more fully appreciated. Several
medical devices
A medical device is any device intended to be used for medical purposes. Significant potential for hazards are inherent when using a device for medical purposes and thus medical devices must be proved safe and effective with reasonable assura ...
have been developed to assist in salvaging the patient's own blood in the perioperative setting. The procedure is frequently used in cardiothoracic and vascular
surgery
Surgery ''cheirourgikē'' (composed of χείρ, "hand", and ἔργον, "work"), via la, chirurgiae, meaning "hand work". is a medical specialty that uses operative manual and instrumental techniques on a person to investigate or treat a pat ...
, during which blood usage has traditionally been high. A greater effort to avoid adverse events due to
transfusion has also increased the emphasis on blood conservation (see
bloodless surgery
Bloodless surgery is a non-invasive surgical method developed by orthopedic surgeon, Adolf Lorenz, who was known as "the bloodless surgeon of Vienna". His medical practice was a consequence of his severe allergy to carbolic acid routinely used in ...
).
Background
Providing safe blood for transfusion remains a challenge despite advances in preventing transmission of
hepatitis B
Hepatitis B is an infectious disease caused by the ''Hepatitis B virus'' (HBV) that affects the liver; it is a type of viral hepatitis. It can cause both acute and chronic infection.
Many people have no symptoms during an initial infection. Fo ...
virus (HBV),
hepatitis C
Hepatitis C is an infectious disease caused by the hepatitis C virus (HCV) that primarily affects the liver; it is a type of viral hepatitis. During the initial infection people often have mild or no symptoms. Occasionally a fever, dark urine, a ...
virus (HCV),
AIDS/HIV
Human immunodeficiency virus infection and acquired immunodeficiency syndrome (HIV/AIDS) is a spectrum of conditions caused by infection with the human immunodeficiency virus (HIV), a retrovirus. Following initial infection an individual m ...
, HTLV-I/II,
West Nile virus
West Nile virus (WNV) is a single-stranded RNA virus that causes West Nile fever. It is a member of the family '' Flaviviridae'', from the genus '' Flavivirus'', which also contains the Zika virus, dengue virus, and yellow fever virus. The v ...
(WNV),
syphilis
Syphilis () is a sexually transmitted infection caused by the bacterium ''Treponema pallidum'' subspecies ''pallidum''. The signs and symptoms of syphilis vary depending in which of the four stages it presents (primary, secondary, latent, an ...
,
Chagas disease,
Zika virus
''Zika virus'' (ZIKV; pronounced or ) is a member of the virus family ''Flaviviridae''. It is spread by daytime-active '' Aedes'' mosquitoes, such as '' A. aegypti'' and '' A. albopictus''. Its name comes from the Ziika Forest of Uganda, w ...
, and transfusion-transmitted
bacterial infection
Pathogenic bacteria are bacteria that can cause disease. This article focuses on the bacteria that are pathogenic to humans. Most species of bacteria are harmless and are often beneficial but others can cause infectious diseases. The number of ...
. Human errors such as misidentifying
patients
A patient is any recipient of health care services that are performed by healthcare professionals. The patient is most often ill or injured and in need of treatment by a physician, nurse, optometrist, dentist, veterinarian, or other health c ...
and drawing blood samples from the wrong person (i.e., wrong blood in tube or WBIT) is more of a risk than transmissible diseases in many developed nations.
Much more common risks of allogeneic transfusion include
allergic transfusion reactions as well as
febrile non-hemolytic transfusion reaction
Febrile non-hemolytic transfusion reaction (FNHTR) is the most common type of transfusion reaction. It is a benign occurrence with symptoms that include fever but not directly related with hemolysis. It is caused by cytokine release from leukocytes ...
s. Additional risks include
transfusion related acute lung injury
Transfusion-related acute lung injury (TRALI) is the serious complication of transfusion of blood products that is characterized by the rapid onset of excess fluid in the lungs. It can cause dangerous drops in the supply of oxygen to body tiss ...
(TRALI),
transfusion associated circulatory overload
In transfusion medicine, transfusion-associated circulatory overload (aka TACO) is a transfusion reaction (an adverse effect of blood transfusion) resulting in signs or symptoms of excess fluid in the circulatory system ( hypervolemia) within 12 h ...
(TACO) and transfusion-associated immunomodulation. TRALI is a potentially life-threatening condition with symptoms such as
dyspnea
Shortness of breath (SOB), also medically known as dyspnea (in AmE) or dyspnoea (in BrE), is an uncomfortable feeling of not being able to breathing, breathe well enough. The American Thoracic Society defines it as "a subjective experience of brea ...
,
fever
Fever, also referred to as pyrexia, is defined as having a body temperature, temperature above the human body temperature, normal range due to an increase in the body's temperature Human body temperature#Fever, set point. There is not a single ...
, and
hypotension
Hypotension is low blood pressure. Blood pressure is the force of blood pushing against the walls of the arteries as the heart pumps out blood. Blood pressure is indicated by two numbers, the systolic blood pressure (the top number) and the dias ...
occurring within hours of transfusion. TACO is a much more common (even with cases being underreported) potentially life-threatening condition involving respiratory compromise within hours of a transfusion. TACO must be suspected when there is respiratory distress with other signs, including pulmonary edema, unanticipated cardiovascular system changes, and evidence of fluid overload (including improvement after diuresis), during or up to 24 hours after transfusion. Transfusion-associated immunomodulation, which may suppress the
immune response
An immune response is a reaction which occurs within an organism for the purpose of defending against foreign invaders. These invaders include a wide variety of different microorganisms including viruses, bacteria, parasites, and fungi which could ...
and cause adverse effects such as a small increase in the risk of postoperative infection.
Other risks such as classic or variant
Creutzfeldt–Jakob disease
Creutzfeldt–Jakob disease (CJD), also known as subacute spongiform encephalopathy or neurocognitive disorder due to prion disease, is an invariably fatal degenerative brain disorder. Early symptoms include memory problems, behavioral changes, ...
(vCJD), an invariably fatal disease, remain worrisome as there are currently no approved tests for which to screen blood donors for this disease. Blood centers worldwide have instituted criteria to reject donors who may have been exposed to classic CJD and vCJD. Screening for transmissible diseases and deferral policies for classic CJD and vCJD designed to improve safety have unfortunately contributed to shrinking the donor pool. Blood shortages exist in the
United States
The United States of America (U.S.A. or USA), commonly known as the United States (U.S. or US) or America, is a country primarily located in North America. It consists of 50 states, a federal district, five major unincorporated territorie ...
and worldwide. In many industrialized countries 5% or less of the eligible population are blood donors.
As a result, some in the global medical community have moved from allogeneic blood (blood collected from another person) towards
autologous
Autotransplantation is the transplantation of organs, tissues, or even particular proteins from one part of the body to another in the same person ('' auto-'' meaning "self" in Greek).
The autologous tissue (also called autogenous, autogene ...
transfusion, in which patients receive their own blood. Another impetus for autologous transfusion is the position of
Jehovah's Witnesses on blood transfusions. For religious reasons, Jehovah's Witnesses may choose not to accept any allogeneic transfusions from a volunteer's
blood donation
A blood donation occurs when a person voluntarily has blood drawn and used for blood transfusion, transfusions and/or made into biopharmaceutical medications by a process called Blood fractionation, fractionation (separation of whole blood com ...
but may accept the use of autologous blood salvaged during surgery to restore their blood volume and homeostasis during the course of an operation, although not autologous blood donated beforehand. Each Jehovah's Witness patient must be individually counselled as to all the possible blood products that are available as they may choose to accept some and not others (i.e., while not accepting whole blood nor any of the four main components of blood,
lasma; platelets; red cells; white cellssome may accept fractions derived from those components, or medications containing such minor fractions); it is an individual choice for each patient.
There are other religious/ non-religious individuals besides Jehovah's Witnesses that would refuse allogeneic blood products but may choose to accept intraoperative blood salvage.
Bloodless options
Ways to avoid the adverse events associated with
allogenic
In ecology, allogenic succession is succession driven by the abiotic components of an ecosystem. In contrast, autogenic succession is driven by the biotic components of the ecosystem. An allogenic succession can be brought about in a number of ways ...
transfusion are often grouped under the umbrella phrase
bloodless surgery
Bloodless surgery is a non-invasive surgical method developed by orthopedic surgeon, Adolf Lorenz, who was known as "the bloodless surgeon of Vienna". His medical practice was a consequence of his severe allergy to carbolic acid routinely used in ...
. There are several so-called bloodless options. These include:
*
Minimally invasive
Minimally invasive procedures (also known as minimally invasive surgeries) encompass surgical techniques that limit the size of incisions needed, thereby reducing wound healing time, associated pain, and risk of infection. Surgery by definition ...
surgical techniques
*
Erythropoietin
Erythropoietin (; EPO), also known as erythropoetin, haematopoietin, or haemopoietin, is a glycoprotein cytokine secreted mainly by the kidneys in response to cellular hypoxia; it stimulates red blood cell production (erythropoiesis) in the bo ...
(a hormone that stimulates peripheral
stem cells
In multicellular organisms, stem cells are undifferentiated or partially differentiated cells that can differentiate into various types of cells and proliferate indefinitely to produce more of the same stem cell. They are the earliest type o ...
in the bone marrow to produce red blood cells)
* Blood salvage procedures
*
Blood substitutes
A blood substitute (also called artificial blood or blood surrogate) is a substance used to mimic and fulfill some functions of biological blood. It aims to provide an alternative to blood transfusion, which is transferring blood or blood-based ...
such as blood volume expanders and oxygen carriers (the latter as yet unlicensed in
North America
North America is a continent in the Northern Hemisphere and almost entirely within the Western Hemisphere. It is bordered to the north by the Arctic Ocean, to the east by the Atlantic Ocean, to the southeast by South America and the Car ...
)
Blood salvage procedures
Cell processing
Regardless of manufacturer, there are many types of cell processors. Cell processors are red cell washing devices that collect anticoagulated shed or recovered blood, wash and separate the
red blood cells
Red blood cells (RBCs), also referred to as red cells, red blood corpuscles (in humans or other animals not having nucleus in red blood cells), haematids, erythroid cells or erythrocytes (from Greek language, Greek ''erythros'' for "red" and ''k ...
(RBC) by centrifugation or filtration such as the HemoClear filter. After, the washed RBCs can be returned to the same patient by reinfusion. RBC washing devices can help remove byproducts in salvaged blood such as activated
cytokine
Cytokines are a broad and loose category of small proteins (~5–25 kDa) important in cell signaling. Cytokines are peptides and cannot cross the lipid bilayer of cells to enter the cytoplasm. Cytokines have been shown to be involved in autocrin ...
s,
anaphylatoxin
Anaphylatoxins, or complement peptides, are fragments ( C3a, C4a and C5a) that are produced as part of the activation of the complement system. Complement components C3, C4 and C5 are large glycoproteins that have important functions in the immu ...
s, and other waste substances that may have been collected in the reservoir suctioned from the surgical field. However, they also remove viable
platelets
Platelets, also called thrombocytes (from Greek θρόμβος, "clot" and κύτος, "cell"), are a component of blood whose function (along with the coagulation factors) is to react to bleeding from blood vessel injury by clumping, thereby ini ...
,
clotting factors
Coagulation, also known as clotting, is the process by which blood changes from a liquid to a gel, forming a blood clot. It potentially results in hemostasis, the cessation of blood loss from a damaged vessel, followed by repair. The mechanism o ...
, and other
plasma proteins
Blood-proteins, also termed plasma proteins, are proteins present in blood plasma. They serve many different functions, including transport of lipids, hormones, vitamins and minerals in activity and functioning of the immune system. Other blood p ...
essential to whole blood and
homeostasis
In biology, homeostasis (British English, British also homoeostasis) Help:IPA/English, (/hɒmɪə(ʊ)ˈsteɪsɪs/) is the state of steady internal, physics, physical, and chemistry, chemical conditions maintained by organism, living systems. Thi ...
. The various RBC-savers also yield RBC concentrates with different characteristics and quality.
Direct transfusion
Direct transfusion is a blood salvaging method associated with
cardiopulmonary bypass
Cardiopulmonary bypass (CPB) is a technique in which a machine temporarily takes over the function of the heart and lungs during surgery, maintaining the circulation of blood and oxygen to the body. The CPB pump itself is often referred to as a he ...
(CPB) circuits or other extracorporeal circuits (ECC) that are used in surgery such as coronary artery bypass grafts (
CABG), valve replacement, or surgical repair of the great vessels. Following bypass surgery, the ECC circuit contains a significant volume of diluted whole blood that can be harvested in transfer bags and re-infused into patients. Residual CPB blood is fairly dilute (
b= 6–9 g/dL; 60–90 g/L) compared to normal values (12–18 g/dL; 120–180 g/L) and can also contain potentially harmful contaminants such as activated cytokines, anaphylatoxins, and other waste substances that have been linked to organ
edema
Edema, also spelled oedema, and also known as fluid retention, dropsy, hydropsy and swelling, is the build-up of fluid in the body's Tissue (biology), tissue. Most commonly, the legs or arms are affected. Symptoms may include skin which feels t ...
and organ dysfunction and need a
diuretic
A diuretic () is any substance that promotes diuresis, the increased production of urine. This includes forced diuresis. A diuretic tablet is sometimes colloquially called a water tablet. There are several categories of diuretics. All diuretics in ...
to reverse.
Acute normovolemic hemodilution (ANH) is a form of autologous transfusion where whole blood is collected from a patient at the start of surgery into a standard blood collection bag with anticoagulant with the simultaneous replacement of intracellular volume using acellular fluids (such as normal saline). The patient's own blood is re-infused at the end of the surgical case (presumably when any bleeding has stopped).
Ultrafiltration
Hemofiltration or ultrafiltration devices constitute the third major type of blood salvage in operating rooms. In general, ultrafiltration devices filter the patient's anticoagulated whole blood. The filter process removes unwanted excess non-cellular plasma water, low molecular weight solutes, platelet inhibitors and some particulate matter through hemoconcentration, including activated cytokines, anaphylatoxins, and other waste substances making concentrated whole blood available for reinfusion.
Hemofilter devices return the patient's whole blood with all the blood elements and fractions including platelets, clotting factors, and plasma proteins with a substantial Hb level. Presently, the only whole blood ultrafiltration device in clinical use is the Hemobag. These devices do not totally remove potentially harmful contaminants that can be washed away by most RBC-savers. However, the contaminants that are potentially reduced by using RBC-savers, as shown by data from
in vitro
''In vitro'' (meaning in glass, or ''in the glass'') studies are performed with microorganisms, cells, or biological molecules outside their normal biological context. Colloquially called "test-tube experiments", these studies in biology an ...
laboratory tests, are transient and reversible
in vivo
Studies that are ''in vivo'' (Latin for "within the living"; often not italicized in English) are those in which the effects of various biological entities are tested on whole, living organisms or cells, usually animals, including humans, and ...
with hemostatic profiles returning to baselines within hours. The key is that
coagulation
Coagulation, also known as clotting, is the process by which blood changes from a liquid to a gel, forming a blood clot. It potentially results in hemostasis, the cessation of blood loss from a damaged vessel, followed by repair. The mechanism o ...
and homeostasis are immediately improved with the return of concentrated autologous whole blood.
Over the years numerous studies have been done to compare these methods of blood salvage in terms of safety, patient outcomes, and cost effectiveness, often with equivocal or contradictory results.
See also
*
Autotransfusionist
An autotransfusionist, also known as a perioperative blood management technologist, is a specialized allied health professional who operates the cell saver machine during surgeries that expect significant blood loss.
The autotransfusionist is re ...
*
Bloodless surgery
Bloodless surgery is a non-invasive surgical method developed by orthopedic surgeon, Adolf Lorenz, who was known as "the bloodless surgeon of Vienna". His medical practice was a consequence of his severe allergy to carbolic acid routinely used in ...
*
Autotransfusion
Autotransfusion is a process wherein a person receives their own blood for a transfusion, instead of banked allogenic (separate-donor) blood. There are two main kinds of autotransfusion: Blood can be autologously "pre-donated" (termed so despite ...
References
Further reading
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External links
UK: Serious Hazards of Transfusion Reports(PDF)
{{DEFAULTSORT:Intraoperative blood salvage
Surgery
Transfusion medicine