Population-based audit of fresh-frozen plasma transfusion practices

BACKGROUND: In contrast to decreasing red blood cell (RBC) consumption in Finland, the use of fresh-frozen plasma (FFP) has been increasing since the 1990s, suggesting that FFP use may not always be optimal. To improve transfusion practices, knowledge of current FFP use and regional, national, and international comparison is necessary. STUDY DESIGN AND METHODS: Nine (of 21) Finnish hospital districts participated. Data concerning FFP-transfused patients in the years 2002 and 2003 were collected from existing computerized medical records into a yearly updated database as part of a Finnish benchmarking project on blood component use. RESULTS: Data included 11,590 FFP-transfused patients and 60,240 FFP units (71.2% of Finnish FFP use) delivered to Finnish hospitals during the study period. FFP was transfused most often to surgery patients (62.8% of FFP transfusion hospital visits) with blood circulatory system problems (32.3% of surgically treated and FFP-transfused patients). In only 65.9 percent of FFP-transfused patients were coagulation variables measured at any point in the hospital episode, and FFP was usually transfused in paired doses. Mean FFP use in Finland is comparable to other countries. CONCLUSION: Although overall FFP use in Finland is similar to that of international figures, it does not ensure best practice. Perioperative staff, being the largest FFP user, should be encouraged to dose FFP based on coagulation variables and body weight. Improvement efforts should be directed to patient groups transfused with large amounts of FFP.     

Vancomycin removal during a plasma exchange transfusion.

OBJECTIVE: To report a case of clinically significant removal of vancomycin during a plasma exchange transfusion in a patient with sickle-cell anemia. CASE SUMMARY: A 46-year-old African American woman with sickle-cell disease was admitted on three separate occasions and treated with vancomycin. Vancomycin serum drug concentrations were obtained on all three admissions. During one of the admissions, a plasma exchange transfusion was performed the same day vancomycin concentrations were obtained. The vancomycin serum drug concentrations were considerably lower than predicted, resulting in potentially subtherapeutic vancomycin concentrations. Bayesian pharmacokinetic forecasting was used in interpreting the vancomycin concentrations. DISCUSSION: Searches from MEDLINE (1966-September 2000) and Drugs and Pharmacology (1990-September 2000) were performed to obtain pertinent published literature. CONCLUSIONS: Plasma exchange transfusions may result in clinically significant removal of vancomycin from the plasma. The potential exists of underdosing vancomycin in patients who are receiving frequent plasma exchange transfusions. Further research may be warranted to determine whether these patients may be candidates for more frequent and vigilant monitoring of vancomycin concentrations.     

Modification of fresh-frozen plasma transfusion practices through educational intervention

The effect of an educational program designed to address misconceptions about the perioperative transfusion of fresh-frozen plasma (FFP) was examined. Results of a baseline audit of FFP use were compared to those of a study subsequent to the educational process. Statistical analysis of the data revealed that the decrease in the number of patients transfused with FFP, from 32 of 2077 operative cases in Group A (baseline) to 18 of 2540 operative cases in Group B (after education), was significant (p less than 0.01). Analysis of the justifications given for transfusion of FFP revealed that the increase in acceptable indications from 47 percent in Group A to 78 percent in Group B was also significant (p less than 0.05). There was no significant difference between the two groups in units of FFP transfused per patient (Group A, 3.66 +/- 3.2, vs. Group B, 2.47 +/- 1.7) or red cells (Group A, 2.84 +/- 5.2, vs. Group B, 5.22 +/- 4.4), and the patterns of platelet transfusion were similar in the two groups. There was a significant difference in the postoperative partial thromboplastin time (Group A, 38.2 +/- 8.7 vs. Group B, 56.3 +/- 24 seconds, p less than 0.01) but no significant difference in postoperative prothrombin time (Group A, 14.1 +/- 2.6 vs. Group B, 15.4 +/- 3.3 seconds). It can be concluded that an educational program designed to address misconceptions in transfusion practice can alter physician performance and thereby reduce the inappropriate use of FFP.     

Automated RBC exchange transfusion:treatment for cerebral malaria

BACKGROUND: Cerebral malaria is a life-threatening complication of Plasmodium falciparum infection. RBC exchange transfusion can reduce the level of parasitemia in this setting. Experience with automated RBC exchange for cerebral malaria may be limited, as most cases occur when the necessary equipment and blood components are not readily available. CASE REPORTS: Three patients were admitted with cerebral malaria. Parasites were found in more than 30 percent of RBCs in two cases and in more than 60 percent of RBCs in the third case. Many RBCs contained multiple organisms. In each case, antimalarial therapy was begun, and an automated RBC exchange was performed emergently with a cell separator. Exchange transfusion was repeated within 24 hours for two patients. Parasitemia levels were less than 1 percent in all patients 24 hours after the last exchange. The neurologic status of these patients returned to baseline, and they were discharged 7 to 18 days after admission. CONCLUSION: Automated RBC exchange transfusion can rapidly reduce the level of parasitemia and restore neurologic functioning in patients with cerebral malaria.     

Automated partial exchange transfusion in sickle cell anemia

Partial exchange transfusion is used to manage several of the complications of sickle cell anemia. Automated exchanges have been performed successfully in thirteen homozygous (SS) sickle cell patients and in one patient with hemoglobin SC. Although the expected acute increase in whole blood oxygen affinity occurred in each patient, there was no clinical evidence of detrimental effects during or immediately after each procedure, and in each case the patient was unchanged or improved when evaluated by exercise testing. By using a discontinuous- flow cell separator, it is possible to decrease the time required to achieve a 50 per cent exchange in an adult to approximately two hours. Transfusion of blood with an antigenic marker permits rapid evaluation of exchange efficiency during the procedure. When partial exchange transfusion is indicated, the discontinuous-flow cell separator provides a safe, rapid, and effective procedure.     

The storage of washed human erythrocytes in a protein-free medium

Protein-free red blood cells were prepared by washing fresh citrate- phosphate-dextrose anticoagulated whole blood and resuspending the cells in a medium containing saline, adenine, phosphate, and glucose (APG). The protein concentration in the APG medium was reduced to 0.0024 percent of the original plasma protein. The 24-hour red blood cell posttransfusion survival after 21 days of storage was 80 percent. Extracellular potassium concentrations were less than the CPD-plasma control after 21 days of storage. Adenosine triphosphate (ATP) concentrations were lower after storage in APG, but intracellular ATP was not closely associated with posttransfusion survival. Hemolysis was slightly increased in the APG group. There appear to be no insurmountable barriers to the use of protein-free media for the storage of washed red blood cells.     

Effect of fresh-frozen plasma transfusion on prothrombin time and bleeding in patients with mild coagulation abnormalities

BACKGROUND: Fresh-frozen plasma (FFP) is frequently transfused to patients with mild prolongation of coagulation values under the assumption that FFP will correct the coagulopathy. There is little evidence to support this practice, however. To determine the effect of FFP on coagulation variables and correlation with bleeding in patients with mildly prolonged coagulation values, a prospective audit of all FFP transfusions at the Massachusetts General Hospital between September 2, 2004, and September 30, 2005, was performed. STUDY DESIGN AND METHODS: All patients transfused with FFP for a pretransfusion prothrombin time (PT) between 13.1 and 17 seconds (international normalized ratio [INR], 1.1-1.85) and with a follow-up PT-INR within 8 hours of transfusion were included. Of 1091 units of FFP transfused, follow-up coagulation values within 8 hours were available for 121 patients (324 units). RESULTS: Transfusion of FFP resulted in normalization of PT-INR values in 0.8 percent of patients (95% confidence interval [CI], 0.0020-0.045) and decreased the PT-INR value halfway to normalization in 15.0 percent of patients (95% CI, 0.097-0.225). Median decrease in PT was 0.20 seconds (median decrease in INR, 0.07). Pretransfusion PT-INR, partial thromboplastin time, platelet count, and creatinine values had no correlation with red blood cell loss. CONCLUSION: It is concluded that transfusion of FFP for mild abnormalities of coagulation values results in partial normalization of PT in a minority of patients and fails to correct the PT in 99 percent of patients.     

Nomograms for the prediction of patient's plasma volume in plasma exchange therapy from height, weight, and hematocrit

The knowledge of plasma volume (PV) is a basic requirement for the standardization of plasma exchange therapy. PV has to be determined by calculation, as the measurement of PV before every plasma exchange is too cost- and time consuming. A known correlation with measured values results from calculation of plasma volume by means of patient's height and weight. But the present equations are only reliable at normal hematocrit. For this reason we modified the Retzlaff-equations and compared the validity of plasma volume predictions, calculated by these and own equations, with plasma volume measured by the 51Cr-method in 59 patients with pathological hematocrit. The correlation coefficient was 0.82 for men and 0.81 for women (2 0.001) with the modified Retzlaff-equations. On the average the relative error was -1.5% for all and 2.8% for fat and thin men. No significant improvement of accuracy was achieved with other equations. Thus, plasma volume can accurately be calculated from height, weight, and hematocrit with our modified Retzlaff-equations in patients with pathological hematocrit, even if they are very fat or thin. Nomograms for men and women were constructed in order to facilitate the calculation.     

Thawing of fresh-frozen plasma with a new microwave oven

In the Federal Republic of Germany fresh-frozen plasma (FFP) is still the most important therapeutic agent for acquired coagulation disorders. However, thawing by waterbath (WB) requires about 30 minutes, which is too slow in emergency situations and carries the risk of bacterial contamination of the FFP. There are conflicting data about the use of microwaves for thawing. Therefore, we examined a new microwave oven (MWO; 2450 +/- 50 MHz), which was developed with our cooperation and allows thawing of FFP in 5 minutes, heating FFP to a surface temperature of 21.5 degrees C. A shaking WB (30 min, 37 degrees C) was also used in parallel for comparison. We measured activated partial thromboplastin time (aPTT), nonactivated PTT (NaPTT), fibrinogen, factors VIII:C, X, and XI, fibrinopeptide A, beta-thromboglobulin (beta-TG), thrombin-AT III-complexes, factor VIII-related antigen, C3c, C4, and the plasticizer di(2-ethylhexyl)phthalate (DEHP) in 84 units of FFP as paired samples from 42 double aphereses. Immediately after thawing there was no significant difference in the coagulation test results of FFP with low-cell contamination, regardless of the thawing procedure. Two hours later, after storage at room temperature, FFP thawed by MWO showed even less change than that thawed by WB (NaPTT, p less than 0.01; FX, p less than 0.01). The differences became more evident in comparison with FFP with higher cell contamination and could be observed immediately after thawing (FVIII:C p less than 0.001; FXI, p less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)     

Automated exchange transfusion in premature and newborn infants with hyperbilirubinemia using a peripheral arteriovenous vascular access device

The technique of exchange transfusion using a plastic catheter in the umbilical vein developed by Diamond and modified by Allen was instrumental in decreasing the mortality and morbidity in newborn infants with jaundice. Allen et al. demonstrated that the development of kernicterus in infants with erythroblastosis with indirect hyperbilirubinemia could be prevented by this method. Since that time numerous modifications of this "single site, push pull technique" have been described to further reduce the risk of morbidity and mortality. On the basis of the successful use of percutaneous radial artery catheters for arterial blood gas monitoring, we developed a technique for exchange transfusion using a peripheral arterial catheter inserted in the radial artery for blood withdrawal and a peripheral venous catheter for replacement of heparinized compatible donor blood. For simultaneous withdrawal and replacement we used two volumetric infusion pumps, one aspirating patients' arterial blood, the other replacing equal volumes of donor blood at exactly the same time. We evaluated our new procedure in 19 newborn infants (group 1) with hyperbilirubinemia who required exchange transfusion. Retrospectively we analysed the data in 18 newborn infants (group 2) treated over a previous period by means of the conventional "one site, push pull" technique using the umbilical vein, and compared the data. Mean birth weights, gestational ages and Apgar scores were similar in both groups, as were volumes of blood used for exchange transfusions. The results were superior in group 1 infants, as reflected by the significantly greater percentage decreases in serum bilirubin concentration and fewer complications. No baby died.(ABSTRACT TRUNCATED AT 250 WORDS)     

Rapid controlled thawing of fresh-frozen plasma in a modified microwave oven

A microwave oven has been specifically modified to permit rapid thawing of fresh-frozen plasma (FFP) by using a rotating disc with a temperature sensor to hold the plasma bag. This modification makes it possible to mix the FFP continuously during thawing, and automatically shuts the oven off when the plasma reaches 21 degrees C. Comparisons were made between FFP thawed in the modified microwave oven and FFP thawed conventionally in a 37 degrees C waterbath. The following tests were done: total protein, albumin, and immunoglobulin concentrations; plasma fibrinogen, factor VIII, and factor IX activities; protein electrophoresis, albumin aggregation, hemolytic complement activity, and plasma particle count and size. In no case was there a significant difference between plasma thawed in the microwave oven compared with that thawed in the waterbath. Further, microwave thawing was reliable and rapid; all units of FFP thawed in less than 6 minutes, and the thawed plasma did not vary by more than 6 degrees C from the preselected final temperature of 21 degrees C. Thus, it appears that controlled thawing of FFP in a microwave oven specifically designed for this purpose is an effective and reliable method and has many advantages over conventional thawing of FFP.     

Phospholipid exchange between plasma and erythrocytes in man and the dog

The turnover of the four major erythrocyte phospholipids has been studied with (32)P, both in vivo and in vitro, in man and the dog. Phosphatidyl serine and phosphatidyl ethanolamine appeared to be stable erythrocyte lipids in both species. Turnover of the phosphate moiety of lecithin and sphingomyelin in the circulating erythrocytes of these two species seems entirely due to an exchange of the whole molecule with the corresponding plasma compound. Exchangeable and nonexchangeable pools of these two cellular lipids were found. In man about 60% of erythrocyte lecithin is exchangeable. The 12 hr fractional turnover of this pool is approximately 13%. Only 30% of the sphingomyelin in human cells appeared exchangeable; this portion had a 12 hr fractional turnover of about 14%. Similar results were obtained in the dog except that in this species about 75% of the erythrocyte sphingomyelin was exchangeable. Inorganic (32)P was not incorporated into any of the four major phospholipids in either species. The present findings aid in estimating quantitatively the effect of plasmaerythrocyte lipid exchange on red blood cell phospholipids.     

Plasma exchange followed by convalescent plasma transfusion in COVID-19 patients

BackgroundCoronavirus disease 2019 (COVID-19) is an emerged pandemic disease with no specific treatment. One of the potential treatments in newly found infectious disease is plasma exchange (PE) with convalescent plasma transfusion (CPT). This case series aimed to evaluate the primary PE and CPT in five Iranian COVID-19 patients.MethodsFive patients with confirmed COVID-19 who had acute respiratory distress syndrome and were supported by mechanical ventilation were treated with two consecutive PE containing fresh frozen plasma (FFP) of healthy donors and 0.9 % saline solution containing 5 % human albumin. Thereafter, CPT was performed just like PE, except that the FFP in this step was substituted with convalescent ABO-matched plasma. Clinical and laboratory factors were evaluated before and after treatments.ResultsThree to Four patients showed lower body temperature and improved oxygen saturation as well as reduced laboratory factors such as c-reactive protein, lactate dehydrogenase, creatine phosphokinase (total and myocardial isoform), aspartate aminotransferase, blood urea nitrogen, bilirubin (total and direct), D-dimer, interleukin-6, and CD4+/CD8 + T cells ratio initially after PE and continued to improve so that they were discharged. One patient due to secondary hemophagocytic lymphohistiocytosis and extensive lung fungal infection was expired.DiscussionOverall, the PE followed by CPT was beneficial in reducing acute inflammation led to a considerable improvement in patients’ clinical features. It seems that PE along with CPT could provide clearance of pro-inflammatory mediators as well as the positive effects of CPT. Controlled studies are required to confirm the effect of PE/CPT compared with other therapeutic approaches.     

Whole blood versus red cells and plasma for exchange transfusion in ABO haemolytic disease

Records of 381 neonates who underwent exchange transfusion (ET) due to ABO haemolytic disease at the Division of Neonatology of Hacettepe University, Ankara, Turkey, between January 1977 and December 2003 were reviewed. Records were kept for the type of blood used in ET, the number of ETs for each infant, adverse event attributable to ET and bilirubin levels before, and 4 and 8 h after each ET. Of 381 infants, 300 were transfused with whole blood, whereas 81 infants were transfused with O red cells suspended in A or B plasma. The re-exchange rate was higher in the whole blood group, compared with the erythrocyte and plasma group. Use of erythrocyte and plasma provided 30% reduction in the number of ETs per patient. Eight hours after the first ET, mean bilirubin levels were 84% of the pre-exchange values in the whole blood group and 73% of the pre-exchange values in the erythrocyte and plasma group (P = 0.001). As the use of O group red cells re-suspended in AB plasma decreased the re-exchange risk compared with O group whole blood, we suggest the use of O red cells re-suspended in AB plasma for the ET in cases of ABO haemolytic disease.     

Automated enzymatic assay for plasma ammonia.

An enzymatic method for determining plasma ammonia with the Du Pont Automatic Clinical Analyzer (aca) is described. The assay requires a sample volume of 500 muL for a kinetic ammonia measurement. The reaction is initiated with glutamate dehydrogenase and the rate of depletion of NADPH is monitored with two measurements, 17 s apart, at 340 nm. Reaction conditions have been optimized for maximum sensitivity through both one-factor-at-a-time and multiple variable response surface optimization techniques. Linearity to 1000 mumol of ammonia per liter of plasma has been achieved. No significant interferences were observed from anticoagulants or endogenous blood components, including pyruvate and oxalacetate. Use of the coenzyme NADPH (instead of NADH) in this aca procedure eliminates the lengthy pre-incubation otherwise required for endogenous dehydrogenase reactions.