Douglas M. Surgenor

Collection and Transfusion of Blood in the United States, 1982–1988

Widespread concern about the safety of the national blood supply, particularly with respect to the human immunodeficiency virus (HIV), has reportedly affected the use of blood products to support patients. To examine these changes, we conducted national surveys of blood collection and transfusion in the United States in 1982, 1984, 1986, and 1987 and made a limited survey of these activities in 1988. Transfusions of whole blood and red cells reached a peak of 12.2 million units in 1986, then declined to 11.6 million units in 1987 and continued to decline in 1988. Transfusions of plasma declined from a peak of 2.3 million units in 1984 to 2.1 million units in 1987. Growth in the use of platelet transfusions (6.4 million units in 1987) also slowed; however, the proportion of platelets transfused as platelets from single donors grew from 11 percent in 1980 to 25 percent in 1987. Donations of autologous blood increased sharply, from less than 30,000 units in 1982 to 397,000 units in 1987, equivalent to 3 percent of the homologous-blood collections. The growth in collections of homologous blood slowed after 1982. The supply of homologous blood reached a peak of 13.4 million units in 1986 and did not grow between 1986 and 1988. These trends in red-cell, plasma, and platelet transfusions appear to have continued through 1988. We conclude that the unprecedented decline in transfusions of whole blood and red cells, coupled with the continued importation of packed red cells from Western Europe and the offsetting effect of autologous predeposits, forestalled serious shortages of blood that could have resulted from the decline in collections of homologous blood. We attribute these changes in blood collection and blood transfusion to the effects of the epidemic of HIV infection.

Determinants of red cell, platelet, plasma, and cryoprecipitate transfusions during coronary artery bypass graft surgery: the Collaborative Hospital Transfusion Study

BACKGROUND: Very little is known about the determinants of blood transfusions in patients undergoing coronary artery bypass graft surgery. STUDY DESIGN AND METHODS: To identify factors that influenced the transfusion of red cells, platelets, plasma, and cryoprecipitate, statistical methods were used to study 2476 consecutive diagnosis‐ related group 106 and 107 patients in five teaching hospitals who underwent coronary artery bypass surgery between January 1, 1992, and June 30, 1993. RESULTS: The likelihood of red cell transfusion was significantly associated with 10 preoperative factors: 1) admission hematocrit, 2) the patients age, 3) the patients gender, 4) previous coronary artery bypass surgery, 5) active tobacco use, 6) catheterization during the same admission, 7) coagulation defects, 8) insulin‐dependent diabetes with renal or circulatory manifestations, 9) first treatment of new episode of transmural myocardial infarction, and 10) severe clinical complications. Platelet and/or plasma transfusions were strongly associated with the dose of red cells transfused. Transfusion requirements and other in‐hospital outcomes were associated with patient characteristics, surgical procedure (reoperation vs. primary procedure), and the conduits used for revascularization (venous graft only, venous and internal mammary artery graft, or internal mammary artery graft only). Blood resource use and donor exposures were evaluated with respect to the risk to patients of contracting hepatitis C virus and human immunodeficiency virus infections. CONCLUSION: The classification of coronary artery bypass graft patients on the basis of attributes known preoperatively and by conduits used yields subsets of patients with distinctly different transfusion requirements and in‐ hospital outcomes.

Red cell transfusions in coronary artery bypass surgery (DRGs 106 and 107)

To study red cell transfusion practice in 3216 coronary artery bypass graft (CABG) cases in 11 hospitals in 1988, abstracted patient records were stratified by diagnosis related group (DRG) (that is, DRG 106, coronary artery bypass without catheterization, or DRG 107, coronary artery bypass with catheterization) and International Classification of Diseases, 9th revision, Clinical Modification (ICD‐9‐CM) surgical procedure code. Means of units per transfused patient, age and length of stay, and in‐hospital mortality rates were significantly greater for patients in DRG 106 than DRG 107. Gender was a significant factor for transfusion outcomes; female patients were more likely to undergo transfusion, and, when transfused, they received more units of red cells than male patients. For a given DRG/ICD‐9‐CM surgical procedure class, significant differences were found between hospitals in the percentage of patients transfused, but not in mean units of red cells per transfused patient. However, within individual hospitals, the proportion of patients transfused and the number of units per transfused patient did not vary significantly across DRG/ICD‐9‐CM procedure classes. These results suggest that circumstances operating within a hospital, still to be identified, had more influence on transfusion decisions than the nature of the surgical intervention.

Red cell transfusions in total knee and total hip replacement surgery

To explore how red cell transfusions were used to support patients who underwent primary and revision hip and knee replacements classified within diagnosis‐related group (DRG) 209 (major joint and limb reattachment procedures), we studied abstracted patient discharge records from 151 United States hospitals in 1986. A total of 9684 units of whole blood and/or separated red cells was used to support 6472 patients. The transfusion use varied by surgical procedure, with patient gender as an influencing factor. Large proportions of patients underwent surgery without requiring transfusion. Among transfused patients, the majority received 1 to 3 units of red cells; however, a minority of patients required multiple transfusions, thereby utilizing a disproportionate share of the blood resource. Comparison of transfusion practice within the seven most active hospitals revealed significant differences (p less than or equal to 0.01) in the percentage of patients actually transfused, but not in the mean number of units of red cell components transfused per transfused patient. Similar findings emerged from comparison of transfusion practice when all hospitals were segregated into five hospital classes on the basis of orthopedic surgical service activity. These effects were seen for both total knee and total hip replacement procedures. It can be concluded that the lack of clearly defined criteria for transfusion contributed to the variations observed.

PHAGOCYTOSIS‐PROMOTING FACTOR OF PLASMA AND SERUM

In the earlier part of this monograph there have been presented scholarly delineations of the various proteins, nutritional factors, hereditary factors, and possible biochemical factors that comprise the natural viricidal and bactericidal property of tissues and body fluids. I should like now to direct your attention to another line of defense in the maintenance of homeostasis: leukocytic phagocytosis, as mentioned by J. G. Hirsch elsewhere in this publication. This system requires the simultaneous presence of 3 component parts: the bacteria or particle to be ingested, living migratory cells to do the ingesting and, finally, extracellular protein factors capable of converting the phenomenon from an interesting laboratory demonstration to a rapidly consummated biologic phenomenon exerting significant effect upon host survival. During the past 4 years our laboratory has been engaged in attempts to isolate and identify the proteins of plasma and serum responsible for this acceleration of phagocytosis. The presence of such phagocytosis-stimulating substances is not a new finding. In fact, the literature in this field dates back more than a half century. Unfortunately, however, this literature sometimes has been enmeshed in semantics: Should such factors be called opsonins? Should such factors be called alexin? Or, indeed, are such factors merely manifestations of complement activity? For purposes of simplification we have grouped all the protein factors that stimulate natural nonimmune phagocytosis under the descriptive term, phagocytosis-promotion factors or PPF. These factors will so be referred to in this report. Points a t which such activity varies from the classic concepts of complement and opsonins will be amplified. It should be noted that these protein factors are additive to the intrinsic ability of leukocytes to be ameboid and to ingest particles a t a slow but measurable rate in even a protein-free medium. These PPF factors also are separate and distinct, we believe, from the specific phagocytic stimulation that occurs in a sensitized system of immune antibodies and appropriate bacterial strains. Finally, the PPF factors also may be independent of alterations in phagocytic rate that can be mediated through metabolic or hormonal influences acting upon the intracellular kinetics of the leukocyte. What, then, are the PPF factors? We believe them to be the proteins that are concerned with the natural regulation of phagocytic rates within the intact animal. In this regard i t should be noted that Y. Matoth, of the Hebrew Medical School, Jerusalem, Israel, while working with us a few years ago, demonstrated the presence of these stimulatory factors in the fetal-cord serum of newborn infants. Admittedly the phagocytic enhancement of these factors was less than that of the whole plasma or serum of the maternal circulation when added to a suspension of the same fetal leukocytes. Nevertheless, welldefined phagocytic stimulation was demonstrable under neonatal circumstances.

Changing patterns of blood transfusions in four sets of United States hospitals, 1980 to 1985

Annual transfusion activity between 1980 and 1985 was surveyed in four sets of United States (US) hospitals, which together accounted for 4.8 percent of the red cell (RBC) transfusions in the US in 1980. Total RBC transfusion rates (total RBCs transfused/1000 hospital admissions) increased between 1980 and 1982 but remained nearly constant between 1982 and 1985. Plasma transfusion dynamics followed a similar pattern, whereas the preoperative deposit of autologous blood by patients accelerated rapidly after 1982. These changes appear to reflect responses to the acquired immune deficiency syndrome epidemic. In contrast, total platelet transfusion rates grew by 76 percent during the 6‐year period, approaching total RBC rates by 1985. This is the first reported evidence in such a large sample of transfusions that total RBC transfusion rates have moderated.

The Collaborative Hospital Transfusion Study: variations in use of autologous blood account for hospital differences in red cell use during primary hip and knee surgery

BACKGROUND: Red cell use in patients undergoing Diagnosis Related Group (DRG) 209 procedures (major joint and limb reconstruction procedures of the lower extremities) has been shown to have large, unexplained interhospital variations.

Preparation and Properties of Serum and Plasma Proteins, XXXV

Advantage has been taken of the altered solubilities of the zinc complexes of plasma proteins in developing a new system of fractionation. Zinc complexes are readily and reversibly formed; they exhibit generally reduced solubility in the neutral pH range, thus obviating exposure of the proteins to harsh conditions of pH, ionic and dielectric strengths. Many zinc protein complexes can be separated without the use of ethanol; the most soluble ones are precipitated from 15% ethanol at neutral pH. A key step involves separation of the proteins whose zinc complexes are water soluble at neutral pH from those which are insoluble. The latter fraction comprises mostly high molecular weight globulins. The water soluble fraction consists mainly of albumin and certain α‐ and β‐pseudoglobulins; it has been called Stable Plasma Protein Solution in view of its properties following zinc removal. The zinc is removed from each fraction by chelation, ion exchange, or a combination of the two. Quantitative data document the separations achieved by this new system of fractionation.

Blood Product Utilization in Hip and Knee Arthroplasty: Effect of Gender and Autologous Blood on Transfusion Practice

Analysis of total blood product support for a 1‐year cohort of patients undergoing hip or knee total joint arthroplasty showed significant differences in transfusion therapy between patients who predeposited autologous blood and those who did not. In primary joint arthroplasty, 51% of nonpredepositing patients undergoing hip replacement and 28% of nonpredepositing patients undergoing knee replacement required red cell transfusions. In revision procedures, 58–61% were transfused. Predepositors requiring only autologous blood received less blood per patient than nonpredepositors; however, 73–87% of primary and 86–88% of revision arthroplasty patients were transfused. Predepositors receiving supplemental allogeneic blood used a volume of red cells comparable to nonpredepositing patients, which was significantly greater than the red cell requirement of predepositors using only autologous blood. Moreover, regardless of predeposit status, the extent of red cell replacement differed between men and women. Male patients presented with significantly higher hematocrits and were less likely to be transfused than females undergoing the same procedure. However, once the transfusion‐decision was made, the average amount of red cells given for each procedure did not show gender‐related variation. Despite differences in admission and lowest observed hematocrits, all patients were discharged with hematocrits in the same range, suggesting that men were replaced with relatively less blood than women. These differences in transfusion practice relating to gender and predeposit status could not be associated with identifiable changes in clinical outcome which might provide rationale for the observed differences in practice.

Utility of DRG and ICD-9-CM classification codes for the study of transfusion issues. Transfusions in patients with digestive diseases.

Red cell transfusions in all patients within specific medical or surgical diagnosis‐related groups (DRGs) and International Classification of Diseases (ICD‐9‐CM) classes were analyzed by a unique body of data that combined abstracted patient discharge records with the numbers of red cell units transfused. Informative measures of transfusion practice within an ICD‐9‐CM class were the proportion of patients transfused, the mean units transfused per patient, and the ratio of standard deviation to the mean of units transfused. Transfusion frequency plots (percentage of patients against units of red cells transfused per patient) revealed the existence of a modal transfusion frequency, as well as an asymmetric tail on the high frequency side. These and other features make it possible to characterize transfusion practice in specific ICD‐9‐CM classes. The mean units of red cells transfused for all patients in a DRG is a measure of blood resource utilization and should be useful in planning to meet future needs.