Storage of buffy-coat-derived platelets in additive solutions: in vitro effects on platelets stored in reformulated PAS supplied by a 20% plasma carry-over.

BACKGROUND AND OBJECTIVES: Platelet additive solutions (PAS) have been shown to be suitable for extended platelet (PLT) storage. Depending on the PAS formulation, the percentage of plasma carry-over contributes to success. Improving PLT quality by optimizing the composition of PAS may allow a reduction to be made in the amount of plasma carried over to the final unit. Reducing the proportion of plasma carried over would probably decrease transfusion of unwanted antibodies and make greater amounts of plasma available for other needs. STUDY DESIGN AND METHODS: Platelets from eight pools of 25 buffy coats were aliquoted and prepared for storage in plasma and different PAS units: InterSol and three alternate PAS named PSM1, PSM2 and PSM3. All PAS units were supplied with a 20% plasma carry-over and stored at room temperature with agitation for 9 days with in vitro testing for metabolic, cellular and activation parameters. Results During storage, PLTs stored in InterSol displayed significantly lower glucose concentration (P < 0.01), lower adenosine triphosphate levels (P < 0.01), a higher mean PLT volume (P < 0.01), a lower response to hypotonic shock response activity (P < 0.01) and a higher CD62P expression (P < 0.01) when compared with PLTs stored in plasma and PSM1-3 solutions. pH was maintained at > 6.8 (day 9) and swirling remained at the highest level (score = 2) for all units throughout storage. CONCLUSION: Our results suggest that PLTs stored in PAS with addition of magnesium, potassium and glucose (PSM2 and PSM3) and 20% plasma carry-over maintained metabolic and cellular characteristics, equivalent to PLTs stored in 100% plasma during 9 days of storage. Our results also suggest that presence of potassium in addition to magnesium or alternatively the concentration of phosphate as well as the supply of additional glucose to normal plasma levels improve in vitro data of PLTs stored in PAS.

Extended storage of whole blood before the preparation of blood components: in vitro effects on red blood cells in Erythro-Sol environment.

BACKGROUND AND OBJECTIVES: Routine procedures for extended storage of whole blood (WB) before the preparation of blood components are of interest primarily for logistical reasons. We stored red cell units in either Erythro-Sol 2 (E-Sol 2, test units, 150 ml added) or in saline-adenine-glucose-mannitol (SAG-M) (reference units, 100 ml added) that were prepared after storage of WB at room temperature for 8, 12, 16 or 19 h after blood collection. STUDY DESIGN AND METHODS: Red blood cells were stored for 42 days. We measured pH, glucose, lactate, haemolysis, red blood cell adenosine triphosphate and 2,3-diphosphoglycerate on days 1, 7, 14, 21, 28, 35 and 42. RESULTS: Haematocrits were significantly lower in E-Sol 2 than in SAG-M due to the higher volume of E-Sol 2 added compared to SAG-M. Significantly reduced levels were found in E-Sol 2 of extracellular pH (throughout storage after 8-h hold and initially after 12-, 16- or 19-h hold), of lactate (initially after 8-h hold and throughout storage after 12-, 16- or 19-h hold), and of haemolysis from day 35 in the 8-h and on day 42 in the 12-h hold group. Significantly increased levels of adenosine triphosphate were seen in E-Sol 2 after 8-h hold (from day 14) and after 12-h hold (at days 21, 35 and 42) compared to SAG-M. Significantly higher concentrations of 2,3-diphosphoglycerate were noticed primarily after 8-h hold of WB. CONCLUSION: The use of E-Sol 2 as a replacement for SAG-M does not significantly improve in vitro data after extended storage of WB at room temperature before preparation of blood components. However, after 8-h hold in vitro characteristics similar to or better than in fresh blood will be maintained for several weeks in E-Sol 2, a situation that makes E-Sol 2 superior to SAG-M when storage of WB is limited to 8 h. Some improvement was noted after 12-h hold as well.

Improved maintenance of 2,3 DPG and ATP in RBCs stored in a modified additive solution.

BACKGROUND: All currently used systems for the storage of RBCs result in loss of 2,3 DPG and an associated increase in affinity for oxygen. Previously, it was demonstrated that a hypotonic additive solution for RBC storage (Erythro-Sol) resulted in prolonged maintenance of 2,3 DPG when blood was collected in 0.5 CPD (half-strength CPD), but not when full-strength CPD was used. The present study aims at improving the quality of stored RBCs collected in ordinary CPD. STUDY DESIGN AND METHODS: A new formulation of Erythro-Sol (Erythro-Sol 2) (pH 8.8) in a larger volume (150 mL) was compared with Erythro-Sol (Erythro-Sol 1). In vitro measures during 49 days of storage in the two additives were compared using WBC-depleted RBCs after whole-blood collection in CPD and separation in an automated blood separation instrument (Optipress II, Baxter Healthcare). RESULTS: The maintenance of RBC ATP and 2,3 DPG was significantly better in Erythro-Sol 2 than in Erythro-Sol 1. The ATP concentration rose to approximately 30 percent above initial level in both systems; however, the maximum occurred on Day 21 in Erythro-Sol 2 as compared with Day 14 in Erythro-Sol 1. In RBCs stored in Erythro-Sol 2, the mean RBC 2,3 DPG concentration increased to 14 percent above initial level on Day 7, then decreased to the initial level on Day 14, whereas in Erythro-Sol 1, the 2,3 DPG had decreased to 85 and 50 percent on Days 7 and 14, respectively. Both intracellular pH and extracellular pH were slightly higher in Erythro-Sol 2 than in Erythro-Sol 1 units but decreased rapidly during the first storage week, which seems to have been the major reason for the limitation in the time of maintenance of 2,3 DPG. Hemolysis was very low in both systems, 0.14 to 0.17 percent on Day 49. The additional amount of inorganic phosphate submitted with Erythro-Sol 2 did not raise concern because the phosphate content in the storage medium, being 1.3 +/- 0.2 mmoL on Day 0, decreased to values below 1 mmoL during most of subsequent storage. CONCLUSION: Erythro-Sol 2 is an improved additive solution for the storage of RBCs.

Quality and standardization in blood component preparation with an automated blood processing technique.

The use of automated blood processors in combination with bottom and top blood containers has been found to improve the standardization and quality of blood components. A study was performed to validate a new type of processor (Optipress II) and compare its performance with a first generation processor (Optipress I). Primary separation on the Optipress II was investigated on 570 mL (+/- 10%) of anticoagulated blood in a nonpaired study. In addition, the quality of the products in routine production was compared between the results of the Optipress I and Optipress II. The whole blood units were kept overnight at room temperature (20 +/- 2 degrees C). Separation was performed under conditions to obtain 55 mL buffy coats with a 50% haematocrit (ht). Platelet concentrate preparation was investigated in a paired study and compared to the routine manual method using PAS II additive solution. Parameters studied were volume, red cell, white cell and platelet counts, ht, haemoglobin (hb, total and free). Primary separation was more efficient in the Optipress II because the platelet count was lower in the erythrocyte concentrates (P < 0.0001), platelets were lower in plasma (P < 0.0001) and platelet counts were higher in buffy coats (P < 0.0001). Buffy coat volume showed less variation (Optipress II VC = 4%, Optipress I VC = 7.4%). Secondary separation did not show differences between the Optipress II and manual method but was advantageous because of the automatic termination of the procedure. Further improvement of standardization in blood component preparation is possible with an automated blood processor, leading to improvement of the quality of blood products for patient care.

Clinical and laboratory experience with erythrocyte and platelet preparations from a 0.5CPD Erythro-Sol opti system.

BACKGROUND: Red blood cells stored as concentrates or suspensions in additive solutions change rapidly their oxygen affinity mainly due to the loss of 2,3-diphosphoglycerate (2,3-DPG). When collected in CPD with half of the normal concentration of citrate and citric acid (0.5CPD) and stored in a new additive solution (Erythro-Sol), 2,3-DPG is better maintained. No studies of the oxygen affinity of red cells stored under these conditions have been published. In Erythro-Sol, red cells have a satisfactory in vivo recovery for 49 days but the conditions after 28 days, within which time most red cell units are transfused, have not been investigated. Of importance is also to be able to make platelet concentrates (PCs) from 0.5CPD blood. Little data are available concerning the clinical usefulness of platelets prepared from 0.5CPD buffy coats (BCs). METHODS: Blood was collected in 0.5CPD, held at 20 degrees C for 3-4 h, then separated with the bottom-and-top technique into red cells, plasma and BC. In a storage experiment with 6 U the 2,3-DPG and P50 values were determined weekly and a number of in vitro parameters were tested on day 28. In 6 donors the in vivo recovery and survival of red cells were determined using a single-chromium technique. Transfusions of 212 0.5CPD-Erythro-Sol red cell units were given to hematological patients under supervision. PCs derived from pools of 0.5CPD BCs suspended in PAS2 (T-Sol) were transfused to 20 thrombocytopenic patients and compared with CPD-BC-PCs suspended in PASI. Corrected count increments (CCI) were determined. RESULTS: The erythrocyte 2,3-DPG and P50 values were normal or slightly subnormal initially but increased to supernormal levels during the 1 week, and remained at these levels for a further 1-3 weeks; the 2,3-DPG was two thirds of normal after 28 days, the P50 was 3.72 +/- 0.28 kPa after 14 days and 2.84 +/- 0.41 after 28 days (mean +/- SD). The P50 values corresponded closely (r2 = 0.903) to 2,3-DPG. The in vivo recovery of 4-week-stored red cells was 89.6 +/- 5.5% and the T50 was 32.2 +/- 2.0 days. No adverse effects were observed in the transfusions. The CCI values did not differ between test and control groups; in both, 3- to 5-day-stored PCs gave lower CCI than fresh (0-2 days) PCs. Patients with acute myeloid leukemia AML (n = 11) had significantly lower CCI values than patients with myelodysplastic syndrome, myeloma and lymphoma (n = 9; CCI 1 h: p = 0.001; CCI 24 h: p = 0.006). CONCLUSIONS: Red cells stored in Erythro-Sol sustain a normal or slightly lowered oxygen affinity for 2-4 weeks, their viability is excellent, and they are well tolerated in clinical transfusions. Platelets prepared from 0.5CPD-BCs cause CCI, of the same magnitude as CPD-BCs.

Evaluation of a new, integral, whole blood filter (RS2000) system for prestorage leucodepletion of SAG-M red cells.

Residual donor leucocytes are responsible for many adverse transfusion reactions. Prestorage leucodepletion may ameliorate these effects and enhance product quality. We studied a bottom and top (BAT) system incorporating an integral filter for whole blood leucodepletion. Our evaluation assessed leucodepletion efficiency as well as in vitro SAG-M red cell quality and storage characteristics. Sixty-six units of blood were collected; test units into the Optipac-pLuS system and controls into the standard triple pack configuration. Test units were held for 4-6 h at room temperature (rt) or 12-18 h at 4 degrees C. The mean leucocyte counts for the SAG-M red cells in the quality and storage trial were 0.6 x 10(6) (rt hold), 0.05 x 10(6) (4 degrees C hold) and 2500 x 10(6) (controls). We observed no significant differences between the groups for Na+, ATP, 2,3-DPG, glucose, lactate and pH during the 49 d storage. The control group, however, showed a greater increase in haemolysis and K+ with time. Autologous in vivo 24 h red cell recovery, after 42 d storage, was > 75%. Adjustment of processing parameters in subsequent studies gave leucodepleted SAG-M red cells with minimal cell loss (9.19%) plus acceptable haemoglobin content (46-76 g/U) and haematocrit (54-62%). This system achieved > 3.5 log leucodepletion with all but one unit containing < 1 x 10(6) leucocytes. The product quality is good and the system suitable for routine use in blood centres.

Stability of blood coagulation factors and inhibitors in blood drawn into half-strength citrate anticoagulant.

Drawing of blood into a citrate-phosphate-dextrose (CPD) solution with a reduced citrate concentration has been shown to improve the maintenance of coagulation factor VIII (F VIII) in plasma and to give possibilities to improve erythrocyte preservation. We studied the quality of plasma obtained from whole blood drawn under continuous mixing into CPD in which the citrate concentration was reduced by 50% (0.5CPD). The blood was stored at room temperature for 8 h before component preparation. We confirmed improved stability of F VIII by 0.5CPD. We found no clinically significant changes in inhibitors to the coagulation and kallikrein systems, and no signs of activation of these systems, during the 8-hour holding time. In control blood drawn into CPD, F VIII and coagulation factor IX decreased by 0.09 IU/ml (8%) and 0.07 U/ml (7%), respectively, otherwise we found no significant differences between 0.5CPD plasma and CPD plasma.

Shall red cell units stand upright, lie flat or be mixed during storage? In vitro studies of red cells collected in 0.5 CPD and stored in RAS2 (Erythrosol).

Red cells were prepared using a new anticoagulant with half the normal amount of citrate and a new additive solution (RAS2, Erythrosol) previously shown to give improved storage conditions, and stored in a highly gas permeable plastic container (PL 2209). Mixing daily and weekly resulted in lower PCO2, higher PO2 and more rapid oxygen saturation of the haemoglobin than storage unmixed in an upright position. Storage horizontally in a lying position unmixed resulted in similar blood gas values as with mixing. The haemolysis was lowest in units mixed once weekly: 0.21 +/- 0.09% after 28 days and 0.26 +/- 0.06% after 56 days. The morphology was better maintained in mixed than in unmixed units. Horizontal storage and mixing once per week seem to be optimal as judged from these in vitro studies.

Evaluation of a new citrate-acetate-NaCl platelet additive solution for the storage of white cell-reduced platelet concentrates obtained from half-strength CPD pooled buffy coats.

BACKGROUND: A new citrate-acetate-NaCl platelet additive solution, identified as PAS 2, was developed to prepare platelet concentrates (PCs) from pooled 0.5 CPD buffy coats (BCs). STUDY DESIGN AND METHODS: A study was undertaken to evaluate PAS 2 in vitro (n = 8) and in vivo (n = 9) against a commercially available solution (Plasma-Lyte A). In a paired in vitro study, a comparison was made of platelet and white cell concentration; blood gases and bicarbonate; glucose and lactate concentration; total intracellular concentration of adenine nucleotides and beta-thromboglobulin release. RESULTS: A lower platelet yield (p < 0.0001) and a higher beta-thromboglobulin release (p < 0.01) are observed with Plasma-Lyte A. For this reason, half-strength (0.5) CPD was changed to full-strength CPD in the clinical study with Plasma-Lyte A. In a clinical evaluation of nine patients with bone marrow failure, all received PCs with both PAS 2 and Plasma-Lyte A that had a shelf life of at least 4 days. Corrected count increments (CCls) were as follows, on average (95% Cl): the CCl at 1 to 4 hours was 22.4 (95% Cl, 15.2-29.4) for PAS 2 and 24.0 (95% Cl, 16.9-31.2) for Plasma-Lyte A; that at 12 to 24 hours was 11.3 (95% Cl, 4.1-18.4) for PAS 2 and 14.2 (95% Cl, 7.1-21.3) for Plasma-Lyte A; and that at 36 to 48 hours was 4.2 (95% Cl, -3.0-11.3) for PAS 2 and 8.7 (95% Cl, 1.1-16.2) for Plasma-Lyte A. No significant difference between the two solutions was found. CONCLUSIONS: PAS 2 and Plasma-Lyte A make important contributions to platelet transfusion quality improvement and give an excellent CCl even after 4 days of storage.

Buffy-coat-derived platelet concentrates prepared from half-strength citrate CPD and CPD whole-blood units. Comparison between three additive solutions: in vitro studies.

The in vitro effects of storage of platelets prepared from 4 or 6 pooled buffy coat (BC) units and stored in a platelet storage medium consisting of 30-40% of CPD plasma or alternatively half-strength citrate CPD (0.5 CPD) plasma and 60-70% of different alternative platelet additive solutions (PASs) were evaluated. Measurements of mean platelet volume, pH, pO2, pCO2, bicarbonate, glucose, lactate, ATP, total adenine nucleotide content, extracellular lactate dehydrogenase or adenylate kinase activity, as markers for disintegration of platelets, and extracellular beta-thromboglobulin, as a marker for activation of platelets, were included in the in vitro studies. Previous studies indicated that a reduction of the citrate concentration from the standard 21 to 8 mmol/l is associated with a significant reduction of the consumption of glucose and production of lactate. Alternatively, similar effects can be obtained by the addition of acetate. In a preliminary paired study, the effects of different concentrations of acetate were tested. In an additional paired study, the effects of CPD plasma in combination with either saline or a PAS containing NaCl (115.5 mmol/l), citrate (10 mmol/l), and acetate (30 mmol/l), pH 7.2 (PAS-2) were evaluated. 0.5CPD plasma in combination with either PAS-2 or a nonacetate PAS (PAS-1) were also tested. The storage of platelets in 0.5CPD plasma was used as a reference. The conclusions are: (1) A minimum acetate concentration of 30 mmol/l is needed to counteract the effects of citrate on the production of lactate. (2) pH and the bicarbonate buffering capacity are significantly better maintained in PAS-2 than in PAS-1.(ABSTRACT TRUNCATED AT 250 WORDS)

Storage of saline-adenine-glucose-mannitol suspended red cells in diethylhexyl phtalate and butyryl-n-trihexyl-citrate plasticized polyvinyl chloride containers. An in vitro comparative study.

Units of whole blood collected into butyryl-n-trihexyl-citrate (BTHC) and diethylhexyl phtalate (DEHP) plasticized polyvinylchloride (PVC) blood storage containers and processed by means of an 'Optipress', which allows automated removal of the buffy coat, were compared. Units collected into standard PVC containers processed by the traditional method (no buffy coat removal) were used as a control group. The red cell concentrates were suspended in saline-adenine-glucose-mannitol (SAGM) and stored 42 days at 2-6 degrees C. Comparison of the buffy coat depleted red cell concentrates showed that red cell energy and oxygen delivery capacity, as evidenced by ATP and 2,3-DPG values, were slightly better preserved in the BTHC plasticized container, compared to the DEHP container. The red cell membrane, however, was slightly less well preserved, (the hemolysis at day 42 with BTHC ww 0.39%; with DEHP, 0.20%) in this container. The higher ATP levels might lead to a better in vivo recovery of stored red cells. In vivo studies comparing both plastic containers, therefore are indicated in order to determine if these differences have practical significance. A longer holding time of the whole blood at room temperature before processing reduced the hemolysis (42 days stored RCC as 0.26%). Slightly more fibrinopeptide A (FPA) generation and marginally lower pH and 2,3-DPG values were observed in this situation. This finding suggests an effect of higher plasticizer levels on the red cell membrane.

Half-strength citrate CPD and new additive solutions for improved blood preservation. I. Studies of six experimental solutions.

Poor stability of plasma factor VIII in whole blood and loss of erythrocyte 2,3-bis-phosphoglycerate (BPG) during red cell storage are limitations with systems for blood component preparation in current use. This study presents attempts to improve post-collection storage conditions in both these respects using half-strength citrate CPD solution (0.5CPD) for blood collection, which has been shown by others to improve the stability of factor VIII, and some compositions of hypotonic additive solutions for red cell storage containing citrate, adenine, mannitol, and phosphate. Guanosine was also included in some of the media. The erythrocyte BPG concentration was maintained at a normal level for 3-4 weeks with the best of the tested compositions. Total adenine nucleotide concentration was maintained at the original level for 49 days and adenosine triphosphate for 28 days. Spontaneous storage haemolysis was low, 0.31% (mean) +/- 0.08-0.10% (SD) after 49 days in the two best compositions. The intracellular pH was 0.2-0.3 pH units higher than the extracellular pH at the beginning of storage, but this difference gradually diminished and disappeared after 4-5 weeks. We suggest two likely explanations of the effects: the maintenance of intracellular pH at a level sufficiently high not to impair BPG synthesis until after several weeks of storage, and a sufficient supply of phosphate needed in the synthesis of organic phosphate compounds. The content of citrate was selected such that the total amount supplied to a patient in a massive transfusion, when using a combination of 0.5CPD plasma and red cell suspension, would be smaller than that provided by a transfusion of CPD whole blood.

Half-strength citrate CPD combined with a new additive solution for improved storage of red blood cells suitable for clinical use.

Currently used systems for red blood cell (RBC) collection and storage for transfusion have the disadvantage that the RBC 2,3-bisphosphoglycerate (BPG) concentration is depleted within two weeks of storage, resulting in a left-shift of the oxygen dissociation curve and a temporarily impaired capacity to deliver oxygen. We have studied the effects on red cell metabolism, morphology and in vivo recovery of 49-day storage of RBC, with collection in half-strength citrate CPD (0.5CPD) and storage in an additive solution containing citrate, adenine, mannitol, phosphate and glucose (RAS2). Traditional CPD-SAGM was used for comparison. Component preparation was performed after an initial holding period of the whole blood at ambient temperature for 8 h. The BPG concentration in 0.5CPD-RAS2 RBC was 0.633 +/- 0.120 mol (mol Hb)-1 as compared to 0.454 +/- 0.138 mol (mol Hb)-1 in CPD-SAGM RBC which implied a decrease to 67 and 48% of normal concentration, respectively. The mean RBC BPG concentration was maintained at the initial level for 28 days in the new system but decreased to very low levels within 14 days in the controls. The total adenine nucleotides were well maintained in both systems, adenosine triphosphate slightly better in the new system. Hemolysis after 49 days was 0.35 +/- 0.21% in the new system and 0.72 +/- 0.25% in the controls (p < 0.001). The morphology was better maintained in the new system (p < 0.001). The 24-hour posttransfusion survival of 49-day stored RBC was 78.9 +/- 7.1%. The membrane leakage of sodium and potassium was not significantly different in the two systems.(ABSTRACT TRUNCATED AT 250 WORDS)