anemia , which can be defined as hemoglobin less than 13 g / dl or hematocrit less than 36% , is a relatively common preoperative finding .
approximately one third of patients are anemic before they undergo joint arthroplasty , with baseline hemoglobin levels between 10 and 13 g / dl . in veterans undergoing noncardiac surgery ,
the incidence of preoperative anemia ( hematocrit < 36% ) was 34% , and in surgical patients who refused transfusions because of religious reasons , 28% had preoperative hemoglobin levels less than 12 g / dl .
the incidence of anemia also increases with age . in a recent study of 296 elderly patients with hip fractures , the mean hemoglobin on hospital admission was 12.1  1.7 g / dl .
anemia is especially prevalent in patients with cancer , and treatment plans often include surgery .
a low initial hemoglobin level measured at disease presentation is a risk factor for further development of anemia throughout the course of treatment . in patients with colorectal cancer
following radical mastectomy for breast cancer , 38% of women were anemic ( hemoglobin < 12 g / dl ) before their first chemotherapy cycle , and 59% became anemic after surgery and chemotherapy . ensuring adequate tissue oxygenation in the surgical setting frequently involves the administration of blood transfusions .
patients with preoperative hemoglobin levels between 10 and 13 g / dl may be three or more times as likely to receive allogeneic blood than those with baseline hemoglobin greater than 14 g / dl . although it has been documented that patients prefer to receive autologous blood , those who are anemic before surgery are not candidates for preoperative autologous donation ( pad ) .
patients with coronary artery disease have impaired hemodynamic and nonhemodynamic responses to hypoxia , and autologous blood donation is not feasible because the hemodilution that ensues may not be tolerated .
endogenous erythropoietin normally stimulates the bone marrow to increase red blood cell ( rbc ) mass under hypoxic conditions , but if this nonhemodynamic response to hypoxia is impaired then hemoglobin levels do not rebound sufficiently .
if hemoglobin levels fall even further during surgery due to blood losses , as commonly occurs , the likelihood of receiving an allogeneic blood transfusion increases .
rbc transfusions are associated with an increased risk for postoperative infections   and tumor recurrence , as well as with a variety of immunologic complications   that may adversely affect surgical patients .
longer hospital stays and higher health care costs have also been linked to blood transfusions .
although allogeneic blood is now reportedly safer than ever , safety issues with the blood supply still exist . furthermore , blood is a scarce resource that is becoming even more so . as the ' baby boomer ' population ages , two factors are converging that will limit blood availability and drive up its cost .
first , the eligible donor pool is shrinking and , second , surgery in these patients , whether elective or otherwise , is on the increase . because of these quality - of - care and economic factors
, the decision to transfuse should be carefully weighed by all members of the surgical team , and transfusion alternatives considered .
the importance of correcting preoperative anemia can not be overemphasized because this condition is known to be associated with poor outcomes after surgery .
coronary artery disease patients with anemia exhibit higher mortality rates and experience more cardiac , abdominal , and renal complications after cardiac or noncardiac surgery than do patients with normal hemoglobin levels .
myocardial ischemia is one of the major complications that occur in anemic patients without overt cardiac disease . in elderly men undergoing radical prostatectomy , st - segment changes and postoperative ischemic episodes
were seen more frequently in those with lower hematocrit . in another study of noncardiac surgical patients of various types comprising a large veterans administration database , perioperative
anemia and blood transfusions were associated with an increased risk for infection , higher mortality rates , and substantial consumption of health care resources .
dunne and coworkers   recently documented a relationship between preoperative anemia and stage of colorectal cancer at diagnosis , and a study of 198 patients with rectal cancer   showed that low preoperative hemoglobin levels were an independent risk factor for mortality ( p < 0.0001 ) . taken together , these reports indicate that preoperative anemia is prevalent , that anemia and blood transfusions are associated with risks and poor outcomes , and that anemia should be treated , preferably with strategies that exclude allogeneic blood .
the human recombinant form of endogenous erythropoietin ( rhuepo ; epoetin alfa ) is indicated for the treatment of anemic patients who are scheduled to undergo elective surgery ( noncardiac and nonvascular ) to reduce the need for allogeneic blood transfusions .
multiple clinical studies involving many different surgical types have shown that preoperative rhuepo is safe and effective .
patients with initial hematocrits between 33% and 39% and who stand to lose up to 3000 ml blood during surgery are among those who can benefit the most [ 21 - 23 ] .
the positive impact of rhuepo is readily apparent in patients undergoing orthopedic surgery , which is often elective and associated with substantial blood losses .
oral iron supplementation and treatment with rhuepo should be considered in any anemic patient ( hemoglobin > 10 and  13 g / dl ) whose risk for transfusion is estimated to exceed 10% .
patients undergoing major orthopedic surgery who received rhuepo 300 units / kg per day for 10 days preoperatively , on the day of surgery , and 4 days postoperatively had a nearly six - fold reduction in allogeneic transfusion risk as compared with patients who received placebo .
in another study that compared rhuepo administered daily ( 300 units / kg per day ) with rhuepo administered weekly ( 600 units / kg per week ) for four doses beginning 21 days before surgery , transfusion requirements were comparable , indicating that the weekly rhuepo regimen also reduces transfusion requirements while improving patient convenience .
rhuepo has also been demonstrated to reduce transfusion requirements in elderly patients undergoing major hip or knee reconstruction , in more heterogeneous populations of patients needing total joint arthroplasty or major hip or knee surgery , and even in children requiring craniosynostosis repair . in cardiac surgery ,
all of seven randomized studies included in a meta - analysis   provided evidence that rhuepo , with or without pad , produced significant decreases in the proportion of patients transfused with allogeneic blood . in another single - blind , randomized study of patients undergoing coronary artery bypass graft surgery , patients treated with low dose ( 100 units / kg ) rhuepo for 4 days before surgery received less than half the amount of autologous blood ( p < 0.01 ) as compared with the control group .
surgery in cancer patients represents a particular challenge because these patients may suffer severe anemia caused by their cancer or its treatment . in patients with a hemoglobin under 8.5 g / dl and with colorectal cancer , 300 iu / kg rhuepo on day 4 before surgery followed by 150
iu / kg for the next 7 days thereafter stimulated erythropoiesis and reduced transfusion requirements compared with placebo .
transfusion requirements were reduced and hemoglobin levels were improved with preoperative rhuepo treatment in patients with gastrointestinal tract cancer   and in those with rectal cancer undergoing surgery .
other patient groups for whom surgery is indicated and in whom preoperative rhuepo exerts beneficial effects include those with prostate cancer , head and neck cancer , and women undergoing gynecologic surgery for benign conditions . when surgical blood losses are anticipated to exceed 3000 ml , rhuepo is effectively used in conjunction with pad . in patients who were to undergo total hip replacement , rhuepo facilitated dose - dependent increases in pad amounting to 4.3 units ( 300 iu / kg ) , 3.4 units ( 150 iu / kg ) , and 3.0 units ( 75 iu / kg ) , as compared with 2.1 units with placebo , and it minimized reductions in hematocrit associated with repeated phlebotomy .
treatment with rhuepo resulted in rapid increases in rbc production ( 3.5 days ) in nonanemic ( hematocrit > 39% ) patients who were participating in an aggressive program for autologous blood donation .
this treatment allowed for higher rbc volumes to be donated compared with placebo - treated patients .
even in anemic gastrointestinal cancer patients , rhuepo facilitated pad compared with patients who were supplemented with iron alone .
other examples of the utility of rhuepo in pad before gynecologic surgery   and orthopedic surgery   can be found . although a field of medicine unto itself , the practice of bloodless surgery is gaining attention and therefore deserves brief mention .
jehovah 's witnesses refuse transfusions on the basis of religious convictions , but are known to survive trauma and surgery with remarkably low hemoglobin levels . in many cases , these patients do so with the pharmacological support of erythropoietic agents [ 49 - 51 ] . in a case study involving 48 jehovah 's witness patients ,
rhuepo was successfully used to avoid transfusions completely during and after elective coronary and heart valve surgery . when used in combination with products that can substitute for blood   (
e.g. the hemoglobin - based oxygen carriers , also known as hbocs ) , there may be complementary effects .
thus , patients wishing to avoid transfusions may have even more options in the future . in conclusion
, preoperative anemia can be effectively managed with minimal exposure to allogeneic transfusions in virtually all surgical specialties .
rhuepo reduces transfusion requirements , facilitates collection of preoperative autologous blood , and is effective alone or with other blood conservation strategies in severe anemia .
surgeons should enthusiastically adopt available therapies that help to avoid transfusions and their accompanying risks , conserve blood , and treat preoperative anemia , with the goal of improving surgical outcomes .
tgm has received research support and honoraria for lectures from ortho biotech products , l.p .
pad = preoperative autologous donation ; rbc = red blood cell ; rhuepo = recombinant human erythropoietin .
 preoperative anemia in a surgical patient predisposes to poor outcomes and allogeneic blood transfusions . as an alternative to transfusions , pharmacologic management of preoperative anemia with recombinant human erythropoietin ( rhuepo ) 
 has been well studied in many different types of surgery . 
 rhuepo , when used alone or in combination with preoperative autologous blood donation before elective surgery , stimulates erythropoiesis and helps to avoid or reduce the need for allogeneic blood transfusions . the clinical evidence on preoperative use of rhuepo in orthopedic , cardiac , and cancer surgery , as well as in bloodless surgery , 
 is reviewed . 
None
Competing interests
Abbreviations