Effectiveness of a prospective physician self-audit transfusion-monitoring system.

BACKGROUND: The purpose of this study was to search for a more effective transfusion-monitoring system than the existing system of retrospective peer review. STUDY DESIGN AND METHODS: This research used a study-control, preintervention and postintervention design, to evaluate the effectiveness of a prospective physician self-audit transfusion-monitoring system that functioned without the direct involvement of transfusion service physicians. This research also evaluated the effectiveness of issuing to physicians a memo with transfusion guidelines. Three process indicators were used to assess physician behavior at various stages of the blood-ordering process: 1) the number of crossmatches ordered per admission, 2) the transfusion-to-crossmatch ratio, and 3) the number of blood units returned to the laboratory after physician self-auditing. The study used two outcome indicators to reflect overall blood utilization: 1) the percentage of patients who received red cell transfusions and 2) the number of blood units transfused per recipient each month. RESULTS: The prospective physician self-audit system implemented at the study hospital did not reverse physician transfusion decisions, and the process of issuing to physicians a memo with transfusion guidelines at the control hospital failed to reduce blood usage. However, a transient reduction in blood utilization was observed at the study hospital. CONCLUSION: The reduction was hypothesized to be due to a Hawthorne effect, in which observed behavior is affected by the subject's awareness of the research study.

Are retrospective peer-review transfusion monitoring systems effective in reducing red blood cell utilization?

OBJECTIVE: This research used a study-control group design and examined data collected from five hospitals to evaluate the effectiveness of retrospective peer-review systems on reducing utilization of red blood cells (RBCs). DESIGN: The effects of retrospective peer-review systems were studied in three parts: (1) trends of RBC utilization were compared by the slopes of linear regression lines that assessed the effect of time on RBC utilization among four study hospitals and one control hospital, (2) diagnosis-specific RBC utilization was compared between the control hospital and one matched study hospital, and (3) the effect of the retrospective review system of one study hospital was assessed by linear regression using data accumulated 1 year before and 2 years after implementation of the program. RESULTS: Three study hospitals showed no significant changes in RBC utilization during the 10-month study period. One study hospital and the control hospital demonstrated trends of reduced RBC use with negative slopes of regression lines; however, there was no difference in the degree of the two slopes, and the diagnosis-specific RBC utilization was not lower at the study hospital than at the control hospital. Furthermore, implementation of the retrospective peer-review system at one study hospital demonstrated no effect on RBC utilization. CONCLUSIONS: We conclude that the retrospective peer-review systems implemented at these four hospitals had no effect on reducing red blood cell utilization.

Infectious disease markers in various groups of donors.

A number of studies have commented on the inadvisability of transfusing unused blood given by autologous and directed donors to patients other than those for whom the blood was originally given (crossing over). It has been stated that these bloods are dangerous and should not be used for allogeneic transfusion. To test this hypothesis, data were taken from a pool of hospital donors. These show that if the donor groups of allogeneic, directed, and autologous are further divided into sets of first time and multiple donors, the incident of infectious disease markers is no higher in one set than the other except for the allogeneic first time donor. Therefore, the "dangerous" donor is actually more likely a first time donor. Following this reasoning, the use of all blood from first time donors should be suspect.

The correlations of surrogate markers with anti-hepatitis C virus and other disease markers.

Testing of donors' sera for the level of alanine aminotransferase (ALT) and the presence of hepatitis B core antibody (anti-HBc) has been required since 1986 as "surrogate" tests for non-A, non-B post transfusion hepatitis (NANB-PTH). With the availability of a test for the antibody to hepatitis C virus (HCV), the need for these two tests and their impact on one hospital are reviewed. Precisely 12.3 percent of the donors were excluded for reactivity to surrogate disease markers but no reactivity to "true" markers. The positive predictive values of these surrogate tests were low and comparable (varying from 7.4 percent to 30 percent). In view of the high rate of donor exclusion and the low rate of correlation with "true" disease markers, the need for these tests needs to be reassessed.

Nursing station order entry for hospital computers.

Tired of illegible labels, unlabeled specimens, and frantic phone calls asking what happened to specimens? This lab was and devised a system to allow test ordering and label printing from nurse stations.

Crossing over of autologous and directed donor blood.

There is a considerable interest in the possibility of crossing over autologous and directed donor blood to other patients. The practicality and safety of this approach depends on the possibility of disease transmission in these groups versus those of the usual homologous donors. A review of the current literature as to the incidence of infectious disease markers shows that the total number of donors studied is rather small, and the results are not too clear. Some studies maintain crossing over is strictly unacceptable; others feel it is safe. The safest approach at this time is to repeat the studies in one's own laboratory and derive the risks and statistics in the local population.

The extension of 4 degrees C storage time of frozen-thawed red cells.

Blood was drawn from volunteer donors and frozen using the high glycerin, mechanical freezing procedure accepted by the United States Navy. Subsequently, the units of blood were thawed and washed. Various anticoagulants were added, and the red cells were stored in a refrigerator at 4 degrees C for periods of up to 28 days. Chemical analyses were performed periodically. These showed that the addition of the anticoagulants ACD, CPD and CPDA-1 caused the red cells to be preserved better than the currently accepted 0.9-percent NaCl, 0.2-percent glucose solution. In vivo 51Cr viability studies performed on blood stored with CPDA-1 for 14 days showed a 24-hour viability of 78.8 +/- 8.4 percent. In a subsequent study, the blood was stored for 21 days prior to freezing and then was rejuvenated and frozen. The cells were thawed, washed, and stored at 4 degrees C with CPDA-1 for an additional 14 days. The 24-hour viability of these cells was determined to be 74.0 +/- 5.1 percent. These findings show that the postthaw storage time of red cells can be increased greatly over the now-accepted 24 hours, if bacterial sterility can be assured.

The prediction of autologous red cell survival.

Nine donors predicted from earlier studies to have increased autologous red cell survival and four predicted to have lesser survival were selected from a pool of previously studied donors. Blood was drawn from these donors, and stored in Neutracel (R-Cutter Lab) preservative for eight hours at room temperature. The platelet rich plasma was removed, the additive solution was introduced, and the red cells were stored for 42 days in an approved refrigerator. At the end of the storage period, a 24 hour Cr-51 viability analysis was performed on each donor. Predicted red cell survival scores correlated reasonably well with the observed percent of red cell viability (r = 0.648). This study suggests that it may be possible to predict increased viability of autologous red cells in certain donors.

The first recorded blood transfusions: 1656 to 1668.

The transfusion of blood was only one of many scientific competitions in which the citizens of France and England engaged in the 1600s. This particular competition laid the foundations for transfusion therapy that were built on 100 years later when more was known about blood. At the time of the studies discussed here, the most important goal seemed to be the establishment of the primacy of the discovery by one or the other nation. In this, most scholars give Lower and the English the first animal-to-animal transfusion and Denys and the French the first animal-to-man transfusion. However, even though this national primacy might not seem so important now, we must realize that the international competition created knowledge that still benefits us today, and those results might not have been produced so swiftly if the competition had not taken place.

The probability of finding suitable directed donors.

A series of tables based on mathematical calculations is given as guidelines for the number of directed donors needed by members of various ethnic/racial groups to provide a desired number of units of blood with a selected probability of achieving this result. From these tables, certain conclusions can be drawn. Unrelated donors who do not know their blood type are an inefficient source of directed donors. Rh-negative patients are unlikely to obtain enough directed-donor units from either related or unrelated donors with confidence unless these donors known their blood type. In general, siblings, parents, and offspring are the most efficient directed donors from the standpoint of compatibility. Cousins, uncles, aunts, nieces, and nephews are not much more likely to be compatible than unrelated donors are. It is easier to obtain suitable directed-donor units among Hispanics than among whites, blacks, or Asians, due to their skewed blood group frequencies. In general, using O-negative directed donors for Rh-positive recipients does not significantly increase the likelihood of finding suitable donors.

Toxicological quandary of the use of bis (2-diethylhexyl) phthalate (DEHP) as a plasticizer for blood bags.

Plastic bags are very useful containers for the storage of blood and blood products since they are relatively transparent, hard to break, can be sealed aseptically with a radio-frequency current, and can be centrifuged for the isolation of blood components. In order to make the plastic more flexible, various agents are added, of which the most common is di- (2-ethylhexyl) phthalate (DEHP). This plasticizer has been found to leach from the plastic into the blood components during the storage period. Some animal studies have shown that this chemical can produce cancers and various tissue abnormalities. The human data from multi-transfused patients do not clearly indicate any specific damage: however, because of the animal studies, work has been carried out to find a non-leachable plasticizer. Several have been found: unfortunately, when survival studies are done, the red cell life span of the stored blood is decreased. Current work seems to indicate that DEHP has a membrane stabilizing function that prolongs the storage time of the red cell. Therefore, there currently is a trade off between plasticizer presence and red cell life span that must be considered when designing new blood storage bags.

Five-week red cell storage with preservation of 2,3 DPG.

The 2,3 diphosphoglycerate (2,3 DPG) content of red cells stored in current anticoagulant-preservative products decreases rapidly after the first few days of storage, and by 3 weeks the red cells are essentially depleted of 2,3 DPG. Because ascorbic acid and ascorbate-2-phosphate (A-2-P) are effective in maintaining erythrocyte 2,3 DPG during liquid preservation, ascorbate was stabilized through autoclaving and subsequent storage by adding it as the trisodium salt of A-2-P to a phosphate-adenine-saline solution at a pH of 8.5 to 9.0. Red cell concentrates prepared from blood drawn into citrate-phosphate-double-dextrose were supplemented with the A-2-P additive solution (AS-4) and studied in vitro and in vivo. Mean 2,3 DPG values for 22 units were 147.6, 113.5, and 82.3 percent of initial value after storage for 3, 4, and 5 weeks, respectively. Maintenance of 2,3 DPG was at the expense of adenosine triphosphate (ATP), which fell to as low as 22.2 percent of initial value after 5 weeks. Despite the low ATP values, the 24 hour 51Cr-labeled red cell recoveries averaged 80.8 and 74.1 percent after 4 and 5 weeks of storage, respectively. The AS-4 system provides a red cell product with acceptable viability and improved oxygen off-loading function.