Extended storage of platelets in a new plastic container. I. Biochemical and morphologic changes

A new polyvinyl chloride container plasticized with tri(2-ethylhexyl) trimellitate (PL 1240 plastic) was evaluated for use in extended platelet storage. Six leukocyte-rich platelet concentrates (mean, 0.6 X 10(9) white cells per bag; range, 0.3 to 1.0 X 10(9) per container) were prepared by removing as much of the platelet-rich plasma from blood as possible. The cells were stored at 22 degrees C on an end-over-end agitator. An average of 1.04 +/- 0.19 X 10(11) platelets was recovered, and the mean pH dropped from 7.23 on day 0 to 6.68 by day 5. At the completion of the storage period. PO2 averaged 80 torr, PCO2 was 35 torr, bicarbonate concentration was 0.5 mM, and lactate concentration 29.5 mM. Thirty-one additional units of platelet concentrates, not deliberately prepared to be leukocyte-rich, on day 5 had a pH of 6.75 +/- 0.39 (mean platelet yield, 0.97 +/- 0.21 X 10(11); PO2 and PCO2 averaged 50 and 48 torr, respectively). Following storage, the cells had an average phase microscopic morphology score of 244 (n = 17). Platelets appeared to be preserved well throughout storage when assessed by transmission and scanning electron microscopy. We conclude that platelets can be stored for 5 days in PL 1240 plastic containers with good preservation of pH and cell ultrastructure.     

Evaluation of platelets prepared by apheresis and stored for 5 days. In vitro and in vivo studies

To evaluate the effect of storage on apheresis platelets collected with a closed-system blood cell separator, an in vitro investigation was performed, with measurements of pH, lactate, ATP, the ratio of ATP to the total adenine nucleotide content, and adenylate kinase. Unmodified apheresis platelets and apheresis platelets with plasma added were compared with conventional platelets stored in PL-1240 or PL-732 plastic containers. During 6 days of storage, there were similar changes in all variables with one exception: the extracellular activity of adenylate kinase was lower in apheresis platelets with plasma than in the other three groups (p less than 0.01). In vivo studies were carried out with 111Indium-labeled autologous platelets in eight volunteers. Apheresis platelets with 100 mL of plasma added were stored in two 1000-mL containers (PL-732) at 22 degrees C during agitation. Platelets from one of the containers were labeled with 111Indium and transfused into the volunteer within 24 hours. Platelets from the other container were labeled after 5 days of storage and transfused into the same donor. There were no significant differences between apheresis platelets stored for 1 day and those stored for 5 days: the mean percentage of recovery was 58.4 and 57.6 percent, t1/2 was 69 and 67 hours, and the survival time was 5.5 and 5.6 days, respectively.     

In vitro and in vivo evaluation of leukoreduced platelets stored for 7 days in CLX containers

BACKGROUND: Extension of platelet (PLT) storage and concomitant use of a bacterial detection system would provide logistical advantages by reducing outdating and improving patient care through promotion of the use of sensitive detection systems. This study evaluated the in vitro characteristics and in vivo viability of leukoreduced PLT units derived from PLT-rich plasma stored for 5 days (control) versus 7 days (test) in CLX plastic containers. STUDY DESIGN AND METHODS: Two whole-blood units were collected from each subject into a leuko-reduction filtration system (Leukotrap RC-PL system, Pall Medical) in a paired design, the second 2 days after the first. These were leukoreduced (Leukotrap PL) and stored for 7 and 5 days. Poststorage samples from test and control units were randomly labeled with (51)Cr or (111)In and simultaneously infused autologously to determine recovery and survival. RESULTS: Small but significant (p < 0.05, paired t test) differences between 5 and 7 days of storage were seen in in vitro variables such as extent of shape change, hypotonic shock response, morphology, and P-selectin expression. In vivo recovery declined on average 11 percent with the two additional days of storage from 54.4 +/- 13.6 to 48.7 +/- 15.0 percent (p < 0.002); survival decreased on average 19 percent from 6.7 +/- 1.0 to 5.4 +/- 1.7 days (p < 0.002). CONCLUSION: Storage for 7 days was associated with reduced recovery and survival and in vitro variables, suggestive of extension of the storage lesion. These differences, however, were small in magnitude and unlikely to have significant clinical effects. Current collection and storage systems provide PLTs that are as functional at 7 days as those licensed for 7-day storage two decades ago.     

In vitro and in vivo evaluation of apheresis platelets stored for 5 days in 65% platelet additive solution/35% plasma

BACKGROUND: In the United States, apheresis platelets (PLTs) are suspended in autologous plasma. PLT additive solutions, long used in Europe, decrease recipient allergic reactions and may reduce the risk of transfusion‐related acute lung injury. We evaluated Amicus‐collected PLTs stored in platelet additive solution (PAS) III (InterSol) for 5 days. STUDY DESIGN AND METHODS: In Study 1, 71 subjects donated two products on a single day—one each stored in 100% plasma or 65% PAS III/35% plasma. Products underwent standard in vitro testing on Days 1 and 5. In Study 2, 43 additional subjects provided Amicus products stored for 5 days in 65% PAS III/35% plasma for in vivo radiolabeled recovery and survival determinations. The effect of approximately 2500 cGy Day 1 gamma irradiation was evaluated in a subset of products. RESULTS: PAS III PLTs (n = 70) had a median Day 5 pH_22°C of 7.2 (lower 95%, 95% tolerance limit, 6.9). Mean Day 5 recovery and survival of radiolabeled PAS III PLTs (n = 33) were, respectively, 80.5 and 72.1%, of fresh autologous PLTs. With 95% confidence, these values were at least 66% of fresh PLT recovery and 58% of survival. All in vitro variables remained within ranges seen in licensed products for irradiated and nonirradiated PAS III PLTs. CONCLUSION: Leukoreduced Amicus PLTs stored in 65% PAS III/35% plasma in PL‐2410 containers maintained pH ≥ 6.9 throughout 5 days' storage. Radiolabeled PLT recovery and survival values met US Food and Drug Administration statistical criteria. Gamma‐irradiated PAS III PLTs demonstrated no significant adverse effects due to irradiation in in vitro testing.     

In vitro and in vivo quality of leukoreduced apheresis platelets stored in a new platelet additive solution

BACKGROUND: Platelets (PLTs) stored in additive solutions (PASs) may reduce the risk of several plasma‐associated adverse transfusion reactions such as allergic reactions and potentially transfusion‐associated lung injury. The objective of this study was to determine the in vitro characteristics and the in vivo radiolabeled recovery and survival of apheresis PLTs (APs) stored in a new PAS and compare the latter to Food and Drug Administration (FDA) criteria. STUDY DESIGN AND METHODS: Hyperconcentrated APs were collected from healthy subjects in a paired crossover study comparing PAS (35% plasma) and 100% plasma‐stored APs (Part 1) up to 7 days and, in Part 2, to determine the in vivo recovery and survival of PAS stored AP at 5 days compared to fresh PLT controls. In vitro and in vivo assays were performed following standard methods. RESULTS: Sixty‐six and 25 evaluable subjects successfully completed Parts 1 and 2, respectively. pH for PAS AP was maintained above 6.6 for 5 days of storage. P‐selectin values were consistent with published values for commonly transfused PLT products. The PAS in vivo PLT recovery (54.3 ± 8.1%) was 86.7% of the fresh control, and survival (6.4 ± 1.3 days) was 78.0% of the fresh control, both meeting the FDA performance criteria. CONCLUSION: APs stored in PAS with 35% plasma carryover maintained pH over 5 days of storage and met current FDA criteria for radiolabeled recovery and survival. The use of PAS for storage of single‐donor PLTs in clinical practice represents an acceptable transfusion product that reduces the volume of plasma associated with PLT transfusion.     

In vitro quality of single-donor platelets treated with riboflavin and ultraviolet light and stored in platelet storage medium for up to 8 days

BACKGROUND: The Mirasol pathogen reduction technology system is known to increase the activation and metabolic rate of platelets (PLTs). Storage of Mirasol PLTs in PLT storage medium (PSM) has the potential to slow this accelerated PLT storage lesion. We investigated the quality of Mirasol‐treated PLTs stored in either 50% SSP+ or 50% Composol for 8 days. STUDY DESIGN AND METHODS: Single‐donor double hyperconcentrates were divided between control and Mirasol‐treated arms and after treatment were suspended in approximately 50% (vol/vol) SSP+ (n = 8) or Composol (n = 7). In vitro markers of PLT activation and/or apoptosis were measured over an 8‐day storage period. RESULTS: Mirasol treatment resulted in increased spontaneous PLT activation and glycolysis and these effects were worsened when PLTs were treated below a certain volume (150 mL). At higher treatment volumes there were no significant differences between treated units stored in either Composol or SSP+. When low‐volume units were stored in Composol the median pH fell below 6.4 on Day 5 and bicarbonate was undetectable, whereas in SSP+ the median pH value was greater than 6.9 and bicarbonate remained at detectable levels, despite other markers of in vitro function being similar to those of Composol. CONCLUSION: Mirasol treatment of PLTs followed by storage in PSM results in increased PLT activation and metabolism to a level similar to that reported for PLTs treated and stored in plasma. Units treated at a low volume (<150 mL) showed poor in vitro quality.     

In vitro evaluation of prestorage pooled leukoreduced whole blood-derived platelets stored for up to 7 days

BACKGROUND: Advantages to storing whole blood-derived platelets (PLTs) as a pool for 7 days would include operational efficiencies and facilitation of bacterial testing and pathogen inactivation. The in vitro quality of pre-storage pooled PLTs stored for up to 7 days was assessed. STUDY DESIGN AND METHODS: Leukoreduced PLTs were pooled before storage (5 units/pool) and stored for either 5 or 7 days. Samples were collected at the time of pooling and either on Day 5 (n=16-29) or on Day 7 (n=4-30) and tested for biochemical and activation markers and morphology and/or shape change. Control PLTs were stored individually for 5 or 7 days and then tested as indicated above. RESULTS: The mean PLT counts (x10(9)/L) were similar: control PLTs, 1344 (464 SD); and prestorage pooled PLTs, 1327 (220 SD; p=0.93). On Day 5, the pH value was significantly lower (p相似文献   

Collection of platelets with a new cell separator and their storage in a citrate-plasticized container

A new apheresis device using microprocessor control for the collection of a high-purity single-donor platelet concentrate was evaluated, as was the storage of platelets for up to 5 days in a citrate-plasticized polyvinylchloride blood bag. The study was conducted in three phases: collection of platelets for in vitro studies and determination of donor safety; autologous transfusion of platelets in healthy volunteers; and transfusion of platelets in patients requiring platelet transfusion therapy. Donors had mild hypocalcemia and minimal changes in blood counts except for a platelet count reduction from 288 +/- 50 x 10(3) (288 +/- 50 x 10(9)/L) to 217 +/- 43 x 10(3) per microL (217 +/- 43 x 10(9)/L). A mean of 3.36 +/- 1.24 x 10(11) platelets was collected in the mean volume of 214 mL with red cell and white cell contamination in the range of 10(7). Morphology and aggregation were as described previously in stored platelets. Platelet survival data in eight subjects showed a mean recovery of 61 +/- 11 percent and mean survival of 5.03 +/- 1.07 days by a weighted-mean model. Patients transfused with platelets had mean increments of 23,000 immediately and of 8000 at 24 hours; corrected count increments were 6000 at 1 hour and 4000 at 24 hours. The platelets were successful in providing hemostasis to these patients. Clinically useful 5-day-stored platelets are obtained by using this apheresis technology with a functionally closed system and a citrate-plasticized blood bag.     

In vivo PLT increments after transfusions of WBC-reduced PLT concentrates stored for up to 7 days

BACKGROUND: Bacterial screening and improvement of storage conditions of leukoreduced PLT concentrates (LR-PCs) allows extension of their storage period from 5 to 7 days. STUDY DESIGN AND METHODS: For in vitro studies, 40 LR-PCs made from five buffy coats and plasma were studied for 8 days. For in vivo studies, routinely produced LR-PCs stored for 2 to 7 days after blood collection were administered to clinically stable thrombocytopenic patients. CI1 h was calculated after 353 transfusions (67 patients), and CCI1 h, after 195 transfusions (55 patients), with pretransfusion PLT counts of not greater than 20 x 10(9) per mL. RESULTS: Storage experiments showed that the pH of LR-PCs remained greater than 6.8 for 8 days, provided that the PLT concentration was less than 1.3 x 10(9) per mL. Routinely produced LR-PCs had a volume of 282 +/- 15 mL (n = 10,193) and contained 329 x 10(9)+/- 40 x 10(9) PLTs (n = 3467). For 7-day-old LR-PCs, 76 of 78 (97%) of the transfusions resulted in a CI1 h of at least 10 and 37 of 39 (95%) in a CCI1 h of at least 7.5, which indicated levels for successfulness. Mean +/- SE values of CI1 h and CCI1 h of 7-day-old LR-PCs were 28.7 +/- 2.3 (n = 78) and 19.0 +/- 2.0 (n = 39), respectively. No significant differences were observed between 5- and 7-day-old LR-PCs transfused with respect to CI1 h and CCI1 h values. CONCLUSION: In vitro and in vivo studies showed that LR-PCs can be stored for up to 7 days with excellent clinical results, provided that they are routinely screened for bacterial contamination.     

Five-day storage of platelets in a non-diethylhexyl phthalate- plasticized container

A non-diethylhexyl phthalate (DEHP)-plasticized blood bag for 5-day storage of random-donor platelet concentrates has been developed. The plastic bag is composed of polyvinylchloride plastic with a butyryl trihexyl citrate plasticizer. The suitability of this plastic for the storage of platelet concentrates for use in clinical transfusion practice was evaluated. In vitro storage studies showed no significant differences at Day 5 for a series of in vitro assays (test plastic vs. control plastic) including pH (7.31 vs. 7.44), lactate dehydrogenase discharge (21.8 vs. 17.1%), pO2 (103 vs. 120 torr), osmotic recovery (52 vs. 57%), and morphology score (527 vs. 516). For paired radiolabeled recovery and survival data from autologous blood donors, results showed equivalence between the test plastic and two control plastics. A small but significant difference between test and control plastics in regard to survival was found by using a linear computer model, but not with a gamma function (multiple-hit) model. For paired transfusions to thrombocytopenic patients, the corrected count increments at 1 to 4 hours (test vs. control) were 13,534 versus 15,494 (p > 0.05, NS). Similar results were seen for corrected count increments determined at 12 to 24 hours. It can be concluded that platelets stored in the test plastic are acceptable for use in clinical practice.     

Preliminary validation of a new standard of efficacy for stored platelets

BACKGROUND: Platelet preparation and storage systems, unlike those for RBC, lack an objective, absolute performance criterion to determine acceptability. Recently, a criterion based on paired comparison with the radiolabeled recovery and survival of "fresh" platelets has been proposed, namely, recovery = two-thirds and survival = half of "fresh" platelets. STUDY DESIGN AND METHODS: Eleven normal subjects donated a unit of leukoreduced apheresis platelets using a standard, approved system. They received an aliquot radiolabeled with 111In or 51Cr (random selection) 4 to 20 hours after donation and, using the other radioisotope, on Day 5 of storage. The recovery was calculated based on the injectate radioactivity. The survival was determined using the multiple-hit model. The area under the platelet survival curve was calculated using the COST program. RESULTS: Reinfusion of platelets less than 20 hours after collection resulted in a recovery of 74.7 +/- 12.3 percent and a survival time of 7.5 +/- 1.1 days. Reinfusion on Day 5 resulted in a recovery of 58.2 +/- 12.0 percent and a survival time of 6.9 +/- 1.4 days, values that were 77.9 +/- 9.5 percent and 91.8 +/- 16.1 percent of the observation using "fresh" platelets, respectively. The area under the curve using Day 5 platelets was 67.8 +/- 11.5 percent of that using "fresh" platelets. CONCLUSION: The proposed criterion for objective evaluation of platelet preparation and storage systems appears applicable to a commonly accepted approach, leukoreduced apheresis platelets stored in plasma for 5 days, and merits evaluation using other collection, treatment, and storage systems.     

Further evaluation of a new standard of efficacy for stored platelets

BACKGROUND: The proposal to assess the viability capabilities of platelets (PLTs) collected, treated, or stored in a developmental system against "fresh" PLTs from the same subject poses several important methodologic issues pertaining to the timing and manner of the collecting and separating the fresh PLTs. This study extended the previous validation of this method of comparing fresh and stored PLTs, applying it to an assessment of apheresis PLTs stored for 7 days with a newly standardized radiolabeling protocol. STUDY DESIGN AND METHODS: Eighteen normal subjects donated 1 unit of leukoreduced PLTs, pheresed with a standard, approved system. They received an aliquot radiolabeled with 51Cr on Day 7 simultaneously with 111In-labeled fresh PLTs that had been separated by a manual method. Recovery and survival were compared to determine whether the stored PLTs were not inferior to the criterion of 67 percent of recovery and 50 percent of survival of fresh PLTs. Separate studies were undertaken to document the similarity of recovery and survival with 51Cr and 111In radiolabeling in PLTs stored to 8 days and to determine the importance of correcting the radioactivity in timed samples for the activity remaining in blood beyond the life span of the retransfused PLTs. RESULTS: PLTs stored for 7 days demonstrated 88.7 +/- 35.2 percent of the recovery and 89.9 +/- 21.2 percent of the survival of PLTs collected via a nonproprietary, manual system and thus met the comparative criterion. In a separate study (n = 12), labeling Day 8 PLTs with 51Cr or 111In resulted in recoveries and survivals that were not different. Radiolabel eluted from labeled PLTs in vitro was taken up by cellular blood elements in a reuptake incubation. CONCLUSION: Apheresis PLTs stored for 7 days met the criterion proposed for comparison with fresh PLTs. This analytic approach is feasible with PLTs collected and prepared via a manual method. A standardized protocol for radiolabeling PLTs with 51Cr and 111In and analyzing the results in a standardized fashion was employed successfully, with the two radioisotopes yielding similar results. The importance of correcting for residual activity after disappearance of injected cells was noted.     

In vitro function and in vivo viability of stored platelet concentrates. Effect of a secondary plasticizer component of PVC storage bags

Previous studies have shown that CL-2399 (Cutter) and PL-130 (Fenwal) polyvinyl chloride (PVC) plastic bags are unsatisfactory for storage of platelet concentrates (PC) at 22 degrees C. In an effort to explain the effects of plastic bags, the chemical make-up of CL-2399 and PL-130 PVC films was determined and compared with that of P1-146 (Fenwal) PVC, which is satisfactory for PC storage at 22 degrees C. The only significant difference between the three materials was the incorporation of tetrahydrofurfuryl oleate (THFO) as a secondary plasticizer in CL-2399 and PL-130. The response of platelets to aggregating agents, uptake of serotonin, recovery from hyptonic stress, and serotonin release during storage following storage in a modified CL- 2399 plastic prepared without THFO and designated CL-3000 (Cutter) was equivalent to PL-146 and far superior to CL-2399. In vivo studies in two laboratories of platelets stored in CL-3000 bags showed satisfactory recovery (56 +/− 4.2% and 46.7 +/− 2.7%) and survival (6.4 +/− 0.4 days and 7.4 +/− 0.6 days). From these studies we conclude that the THFO secondary plasticizer component of PL-130 and CL-2399 is the cause of the poor platelet viability of platelets stored in these plastic bags. The mechanism of impairment is not known. The causative agent(s) may be degradation products of THFO (formed during manufacture of the PVC film) that are leached from the plastic into PC during storage.