Platelet corrected count increments by apheresis platform.

BACKGROUND: Automated blood collection platforms use different technological systems to isolate and collect individual blood components. These unique systems could potentially result in differences in platelet in vivo viability, as measured by the corrected count increment (CCI). STUDY DESIGN AND METHODS: This retrospective study evaluated CCI data of platelet transfusions among oncology patients who received multiple unmanipulated apheresis platelets between January 1, 2006 and December 31, 2009. Apheresis platelets were collected from our community blood center by standard procedures using two different collection systems and were transfused to patients in a blinded manner. RESULTS: The CCI of the platelet recipient was significantly higher at 0-2 hours post-transfusion among the individuals who received platelets collected on Trima Accel (Terumo BCT) (mean = 6281, standard deviation = 3650) compared to the platelets collected by the Amicus system (Fresenius Kabi) (mean = 5251, standard deviation = 3311, p = 0.004). CONCLUSIONS: These hypothesis-generating data suggesting improved recovery and survival of Trima Accel platelets demonstrate the need for the investigation and implementation of the best collection methods to provide better platelet transfusion support.

The impact of platelet additive solution apheresis platelets on allergic transfusion reactions and corrected count increment (CME).

BACKGROUND: Allergic transfusion reaction (ATR) incidence ranges from 1% to 3% of all transfusions. We evaluated the impact of InterSol platelet additive solution (PAS) apheresis platelets (APs) on the incidence of ATRs and the posttransfusion platelet (PLT) increment. STUDY DESIGN AND METHODS: This retrospective study evaluated all ATRs among patients at a university hospital that maintained a mixed inventory of PAS APs and non-PAS APs (standard plasma-suspended PLTs). Corrected count increments (CCIs) were calculated for AP transfusions of individuals who received both a PAS and a non-PAS AP transfusion within a 7-day period. Hypothesis testing was performed with chi-square test for dichotomous variables and t tests for continuous variables. RESULTS: The incidence of ATRs among the non-PAS APs was 1.85% (72 ATRs/3884 transfusions) and 1.01% (12 ATRs/1194 transfusions) for PAS APs (risk ratio [RR], 0.54; 95% confidence interval [CI]=0.30-0.99; p=0.04). However, there was no difference in the incidence of febrile nonhemolytic transfusion reactions between non-PAS APs (incidence, 0.70%; 27/3884) compared to PAS APs (incidence, 0.59%; 7/1194; p=0.69). Among 223 individuals with paired non-PAS and PAS AP transfusions, the mean CCI at 1 to 4 hours after transfusion was 4932 (95% CI, 4452-5412) for non-PAS APs and was lower for PAS APs (CCI, 3766; 95% CI, 3375-4158; p ≤ 0.001). However, there was no significant difference in mean CCI at 12 to 24 hours between non-PAS (CCI, 2135; 95% CI, 1696-2573) and PAS APs (CCI, 1745; 95% CI, 1272-2217; p=0.14). CONCLUSIONS: PAS APs substantially reduce the number of ATRs. CCIs for PAS APs were lower immediately after transfusion, but not significantly different at 12 to 24 hours.

The impact of apheresis platelet manipulation on corrected count increment.

BACKGROUND: Concentrating and washing apheresis platelets (APs) substantially reduce the number of allergic transfusion reactions likely due to removal of plasma. However, these processes may damage platelets (PLTs). This study evaluated whether concentrating or washing APs decrease the corrected count increment (CCI). STUDY DESIGN AND METHODS: This retrospective study evaluated individuals who initially received unmanipulated APs and subsequently received concentrated and/or washed APs at a large university hospital between 1998 and 2009. Concentrated units were prepared by reducing the plasma volume of APs by a goal of more than 67%. Washed units were prepared by washing the APs with 1 L of normal saline. The CCI (PLTs [×10(6)] × m(2)/L) for all transfusions was calculated. Hypothesis testing was performed with t tests for continuous variables and chi-square tests for dichotomous variables. RESULTS: We evaluated 121 individuals: 46 patients who received unmanipulated, concentrated, and then washed APs; 59 patients who received unmanipulated and then concentrated APs; and 16 patients who received unmanipulated and then washed APs. Patient demographics were similar among the three groups. The mean CCI for unmanipulated AP transfusions at 0 to 2 hours posttransfusion was significantly higher than concentrated and washed PLT transfusions (p<0.001). When accounting for PLT loss due to manipulation, concentrating APs did not impact the CCI. However, the CCI remained significantly lower for washed products at all time points after transfusion (40.7% mean reduction at 20-24 hr, p<0.001). CONCLUSIONS: Washing APs significantly reduces PLT count recovery and survival, as demonstrated by a significantly reduced CCI.

A comprehensive program to minimize platelet outdating.

BACKGROUND: Platelet (PLT) transfusions are essential for patients who are bleeding or have an increased risk of bleeding due to a decreased number or abnormal function of circulating PLTs. A shelf life of 5 days for PLT products presents an inventory management challenge. In 2006, greater than 10% of apheresis PLTs made in the United States outdated. It is imperative to have a sufficient number of products for patients requiring transfusion, but outdating PLTs is a financial burden and a waste of a resource. STUDY DESIGN AND METHODS: We present the approach used in our institution to anticipate inventory needs based on current patient census and usage. Strategies to predict usage and to identify changes in anticipated usage are examined. Annual outdating is reviewed for a 10-year period from 2000 through 2009. RESULTS: From January 1, 2000, through December 2009, there were 128,207 PLT transfusions given to 15,265 patients. The methods used to anticipate usage and adjust inventory resulted in an annual outdate rate of approximately 1% for the 10-year period reviewed. In addition we have not faced situations where inventory was inadequate to meet the needs of the patients requiring transfusions. CONCLUSION: We have identified three elements of our transfusion service that can minimize outdate: a knowledgeable proactive staff dedicated to PLT management, a comprehensive computer-based transfusion history for each patient, and a strong two-way relationship with the primary product supplier. Through our comprehensive program, based on the principles of providing optimal patient care, we have minimized PLT outdating for more than 10 years.

Allergic transfusion reactions to platelets are associated more with recipient and donor factors than with product attributes.

BACKGROUND: Mechanisms of allergic transfusion reactions (ATRs) are not well understood. The aim of this study was to distinguish recipient-, donor-, and product-specific factors associated with ATRs. STUDY DESIGN AND METHODS: We conducted a retrospective cohort study of apheresis platelet (AP) products transfused from April 2000 through March 2010. The concordance rate of ATRs when split AP products were transfused to at least two individuals was compared to the overall ATR rate among all AP products. Per-person ATR rates also were compared to the overall ATR rate. RESULTS: We observed 1616 ATRs among 93,737 transfusions, for an overall incidence of 1.72% (95% confidence interval [CI], 1.64%-1.81%). Of the 1616 ATRs, 630 occurred when split AP products were transfused to at least two recipients. Of these 630 AP products, ATRs were observed in at least two different recipients of the same AP collection only 6 of 630 times, for a concordant incidence of 0.95% (95% CI, 0.35%-2.06%), which is similar to the overall ATR rate (p = 0.17). On an individual level, 30.0% of recipients had ATR rates of more than 5%, and these 30.0% accounted for 62.1% of ATRs. Donors of AP products associated with concordant ATRs donated AP products that had an ATR rate of 5.8% (95% CI, 3.1%-9.7%), which is higher than the overall ATR rate (p < 0.001). CONCLUSIONS: An observed ATR does not predict an ATR in a different recipient of a split AP product. A minority of platelet recipients accounts for the majority of ATRs. Some donors are strongly associated with ATRs. Consequently, recipient and donor factors are implicated in the mechanism of ATRs.

Bacterial culture reduces but does not eliminate the risk of septic transfusion reactions to single-donor platelets.

BACKGROUND: Transfusion-associated bacterial sepsis is a significant risk of morbidity and mortality related to platelet (PLT) transfusions. Previously the rate of septic PLT transfusion reactions (SPTRs) to single-donor PLTs (SDPs) in our hospital was determined to be 1 in 15,098 (6.6 per 100,000; 95% confidence interval [CI], 0.17-36.9 per 100,000) transfusions. The goal of this study was to determine if bacterial testing of SDPs reduced the rate of SPTRs in our hospital. STUDY DESIGN AND METHODS: An automated microbial detection system was implemented by our blood supplier in February 2004. A retrospective examination of the number of SPTRs that have occurred to SDPs at our hospital since that time was performed, using the same criteria used before bacterial screening. Transfusions over a 3.5-year period were examined. Clinical and laboratory data were gathered and correlated from transfusion reaction files and three independent computer systems. RESULTS: From March 1, 2004, through August 31, 2007, there were 49,625 transfusions of SDPs with 1096 transfusion reactions reported. Only one reaction detected the same organism in two of three sites, meeting our criteria for a SPTR. The rate of SPTRs in SDPs was identified as 1 in 49,625 (2.0 per 100,000; 95% CI, 0.05-11.2 per 100,000). This represents a 69.7% reduction in the incidence of SPTRs (p = 0.41). CONCLUSION: With the implementation of bacterial testing, a decrease in the rate of SPTRs to SDPs from 6.6 per 100,000 to 2.0 per 100,000 transfusions was observed. Although not significant, these findings suggest a trend.

Profound thrombocytopenia and survival of hematopoietic stem cell transplant patients without clinically significant bleeding, using prophylactic platelet transfusion triggers of 10 x 10(9) or 20 x 10(9) per L.

BACKGROUND: A trigger of 10 x 10(9) per L for prophylactic platelet (PLT) transfusions is generally recommended for stable thrombocytopenic patients who receive chemotherapy, based on studies showing similar incidence, severity, and fatality of bleeding compared with the 20 x 10(9) per L trigger. The outcome of thrombocytopenic nonbleeding patients has not been well described. This retrospective analysis evaluates thrombocytopenia and survival of 381 hematopoietic stem cell transplant (HSCT) patients without clinically significant bleeding, with 10 x 10(9) and 20 x 10(9) per L prophylactic triggers. STUDY DESIGN AND METHODS: A total of 170 patients who received prophylactic PLT transfusions at 20 x 10(9) per L (1997-1998, SP1) and 211 patients who had prophylaxis at 10 x 10(9) per L (1999-2001, SP2) were identified as nonbleeding patients. PLT counts and clinical complications were assessed within 100 days from HSCT. RESULTS: PLT counts less than or equal to 10 x 10(9) per L were found in 69.2 percent of patients in SP2 and 38.3 percent in SP1 (p < 0.001). Profound thrombocytopenia (4+ PLT counts

Acute bleeding complications in patients after hematopoietic stem cell transplantation with prophylactic platelet transfusion triggers of 10 x 10(9) and 20 x 10(9) per L.

BACKGROUND: Prophylactic platelet (PLT) transfusions are given as a standard care in patients with hematologic malignancies undergoing hematopoietic stem cell transplantation (HSCT). This retrospective analysis evaluates utilization of blood transfusions, risk of bleeding, and survival in 480 HSCT patients at 10 x 10(9) and 20 x 10(9) per L prophylactic trigger levels. STUDY DESIGN AND METHODS: A total of 224 patients received prophylactic PLT transfusions at 20 x 10(9) per L threshold (1997-1998, SP1); 256 patients had prophylaxis at 10 x 10(9) per L (1999-2001, SP2). Bleeding scores were assigned daily. RESULTS: A slight reduction in PLT transfusions per patient in SP2 compared with SP1 was not statistically significant (odds ratio, 0.82; 95% confidence interval, 0.51-1.33; p = 0.416), yet a significantly higher proportion of patients in SP2 had PLT counts less than or equal to 10 x 10(9) per L compared to SP1 (p < 0.001). In patients who bled, however, there was no excess exposure to low PLT counts before bleeding started. A substantial number of patients who bled received PLT transfusions above the goal before bleeding started (82.9% in SP2, 41.5% in SP1) because of medical complications that associated with increased risk of bleeding. Bleeding incidence was similar in both study periods (21.9% in SP1, 16.4% in SP2; p = 0.526). Bleeding was significantly associated with reduced survival in both study periods. CONCLUSIONS: Patients who bled were usually placed on a higher threshold before the onset of their major bleeding event and were not exposed to additional risk of bleeding from thrombocytopenia. Similarity in bleeding incidence between study periods appears to associate with adjustments to high-risk conditions and may not reflect consequences of the lower transfusion threshold.