Duration of platelet storage and outcomes of critically ill patients

Effect of platelet storage duration on platelet increment and clinical outcomes in critically ill patients - A randomised controlled trial

BACKGROUND AND OBJECTIVES

Platelet storage duration may influence transfusion effectiveness and patient outcomes.The present study aimed to evaluate the effect of platelet storage duration on platelet increment and clinical outcomes in patients admitted to the intensive care unit (ICU).

MATERIAL AND METHODS

This prospective, open-label, randomized controlled trial, conducted at a single centre, enrolled ICU patients requiring platelet transfusion. Patients were randomly assigned to receive platelet concentrates aged ≤ 3 days (Group 1) or 4-5 days (Group 2). Platelet increments were assessed by Absolute Platelet Count Increment (ACI), Corrected Count Increment (CCI), and Percentage Platelet Recovery (PPR). Clinical outcomes including bleeding, infection rates, ICU stay, red cell transfusion requirements, and mortality were also monitored.

RESULTS

Patients transfused fresher platelets (Group 1) had higher median ACI, CCI and PPR at 1 h compared to those transfused older platelets (Group 2) though the difference was not statistically significant. At 24 h, Group 1 patients had a median ACI of 28,000/µl compared to 14,000/µl in Group 2(p = 0.001). The median CCI was 16,800 in Group 1 versus 8,200 in Group 2(p = 0.001). Group 1 also had a higher median PPR of 45.7% compared to 23.6% in Group 2(p = 0.011).There was no significant difference in clinical outcomes such as bleeding, infection rates, ICU stay, or mortality between the groups. Multivariate analysis indicated that co-morbidities and higher APACHE-III score were associated with increased mortality.

CONCLUSION

Transfusion of fresher platelets resulted in higher increments and transfusion effectiveness but did not affect clinical outcomes or mortality.

TRIAL REGISTRATION DETAILS

Clinical Trials Registry of India (CTRI/2023/03/050676).

An evaluation of the clinical impacts of 7-day platelets

BACKGROUND

In August 2017, Canadian Blood Services extended the shelf-life of platelet concentrates from 5 to 7 days. The clinical impacts of this policy change remain unclear.

STUDY DESIGN AND METHODS

We used a before-after retrospective design of platelet-transfused adult inpatients in Hamilton, ON, Canada. Data were captured for 18 months before (Period 1: February 2016-July 2017) and 18 months after (Period 2: September 2017-February 2019) 7-day platelet implementation. Primary outcome was absolute platelet count increment (ACI) in univariate and multivariate analyses adjusted for confounders. Data were obtained from our institution's transfusion database, Ontario's Transfusion Transmitted Injuries Surveillance System, and the blood supplier.

RESULTS

Overall, 1360 patients with single dose platelet transfusions were included in Period 1 and 1211 patients in Period 2. Median age at admission was 66 years, and approximately 40% of patients underwent cardiac surgery. Using a non-inferiority margin of -10 × 10⁹ /L, platelets transfused during the 7-day storage period were non-inferior to those transfused in the 5-day storage period [mean count difference - 4.63 × 10⁹ /L (95% CI -7.40 to -1.87, p = 0.0001)]. However, platelet ACIs following transfusion consistently trended lower in the 7-day group for all patients and subgroups. No differences in secondary clinical outcomes were observed. Platelet expiry reduced from 8.1 to 6.3% (p < 0.0001).

CONCLUSION

Platelet transfusions following 7-day storage policy were non-inferior to transfusions in the 5-day policy period, although reduced ACIs were observed. There were no increases in adverse clinical outcomes.

Aged versus fresh autologous platelet transfusion in a two-hit healthy volunteer model of transfusion-related acute lung injury

BACKGROUND

Transfusion-related acute lung injury (TRALI) is a severe complication of blood transfusion that is thought of as a two-hit event: first the underlying patient condition (e.g., sepsis), and then the transfusion. Transfusion factors include human leukocyte antigen antibodies or biologic response modifiers (BRMs) accumulating during storage. Preclinical studies show an increased TRALI risk with longer stored platelets, clinical studies are conflicting. We aim to discover whether longer platelet concentrate (PC) storage time increases TRALI risk in a controlled human experiment.

STUDY DESIGN AND METHODS

In a randomized controlled trial, 18 healthy male volunteers received a first hit of experimental endotoxemia (2 ng/kg lipopolysaccharide), and a second hit of fresh (2-day old) or aged (7-day old) autologous PC, or physiological saline. After 6 h, changes in TRALI pathways were determined using spirometry, chest X-ray, and bronchoalveolar lavage (BAL).

RESULTS

All subjects reacted adequately to lipopolysaccharide infusion and satisfied SIRS criteria (increased pulse [>90/min] and temperature [>38°C]). There were no differences between the saline, fresh, and aged PC groups in BAL-fluid protein (95 ± 33 μg/ml; 83 ± 21 μg/ml and 104 ± 29 μg/ml, respectively) and relative neutrophil count (1.5 ± 0.5%; 1.9 ± 0.8% and 1.3 ± 0.8%, respectively), nor in inflammatory BAL-fluid BRMs (Interleukin-6, CXCL8, TNFα , and myeloperoxidase), clinical respiratory parameters, and spirometry results. All chest X-rays were normal.

CONCLUSIONS

In a human endotoxemia model of autologous platelet transfusion, with an adequate first hit and platelet storage lesion, transfusion of 7-day-old PC does not increase pulmonary inflammation compared with 2-day-old PC.

Impact of Blood Product Transfusions on the Risk of ICU-Acquired Infections in Septic Shock

OBJECTIVES

Transfusions of blood products are common in critically ill patients and have a potential for immunomodulation. The aim of this study is to address the impact of transfusion of blood products on the susceptibility to ICU-acquired infections in the high-risk patients with septic shock.

DESIGN

A single-center retrospective study over a 10-year period (2008-2017).

SETTING

A medical ICU of a tertiary-care center.

PATIENTS

All consecutive patients diagnosed for septic shock within the first 48 hours of ICU admission were included. Patients who were discharged or died within the first 48 hours were excluded.

INTERVENTIONS

RBC, platelet, and fresh frozen plasma transfusions collected up to 24 hours prior to the onset of ICU-acquired infection.

MEASUREMENTS AND MAIN RESULTS

During the study period, 1,152 patients were admitted for septic shock, with 893 patients remaining alive in the ICU after 48 hours of management. A first episode of ICU-acquired infection occurred in 28.3% of the 48-hour survivors, with a predominance of pulmonary infections (57%). Patients with ICU-acquired infections were more likely to have received RBC, platelet, and fresh frozen plasma transfusions. In a multivariate Cox cause-specific analysis, transfusions of platelets (cause-specific hazard ratio = 1.55 [1.09-2.20]; p = 0.01) and fresh frozen plasma (cause-specific hazard ratio = 1.38 [0.98-1.92]; p = 0.05) were independently associated with the further occurrence of ICU-acquired infections.

CONCLUSIONS

Transfusions of platelets and fresh frozen plasma account for risk factors of ICU-acquired infections in patients recovering from septic shock. The occurrence of ICU-acquired infections should be considered as a relevant endpoint in future studies addressing the indications of transfusions in critically ill patients.

Post-transfusion platelet responses in critically ill cancer patients with hypoproliferative thrombocytopenia

BACKGROUND

Platelet transfusion is aimed at increasing platelet counts to prevent or treat bleeding. Critically ill cancer patients with hypoproliferative thrombocytopenia are high consumers of blood products. We herein described their post-transfusion platelet responses in the intensive care unit (ICU) and analyzed the determinants of poor post-transfusion increments.

STUDY DESIGN AND METHODS

This was a single-center 9-year (2009-2017) retrospective observational study. Patients with malignancies and presumed or proven hypoproliferative thrombocytopenia who had received at least one platelet transfusion in the ICU were included. Poor post-transfusion platelet increments were defined as body surface-adjusted corrected count increment (CCI) <7, or alternatively as weight-adjusted platelet transfusion recovery (PTR) <0.2. Patients were deemed refractory to platelet transfusions when two consecutive ABO-compatible transfusions resulted in poor platelet increments.

RESULTS

A total of 1470 platelet transfusions received by 326 patients were analyzed. Indications for platelet transfusions were distributed into prophylactic (44.5%), peri-procedural (18.1%) and therapeutic (37.4%). Regardless of indications, 54.6% and 55.4% of transfusion episodes were associated with a CCI <7 or a PTR <0.2. Factors independently associated with poor post-transfusion increments were lower body mass index, spleen enlargement, concurrent severity of clinical condition, fever ≥39°C, antibiotic therapy and increased storage duration of platelet concentrates. Eventually, 48 patients developed refractoriness to platelet transfusion, which was associated increased incidence of bleeding events.

CONCLUSION

Platelet transfusions are often associated with poor increments in critically ill cancer patients with hypoproliferative thrombocytopenia. The findings suggest amenable interventions to improve the platelet transfusion practices in this setting.

Microbiological Screening of Platelet Concentrates in Europe

The risk of transfusion-associated sepsis due to transmission of bacteria is a persistent problem in the transfusion field. Despite numerous interventions to reduce the risk, cases of bacterial sepsis following transfusion are repeatedly being reported. Especially platelet concentrates are highly susceptible to bacterial contaminations due to the growth-promoting storage conditions. In Europe, blood establishments and national authorities have implemented individual precaution measures to mitigate the risk of bacterial transmission. To obtain an overview of the different approaches, we compiled information from national authorities, blood establishments, and the current literature. Several aspects such as the shelf life of platelets, time of sampling and the applied control measures are compared between the member states. The analysis of the data revealed a broad heterogeneity of procedures on a national level ranging from platelet release without any safety testing up to mandatory screening of all platelet concentrates prior to transfusion. Despite the substantial progress made in recent years, several bacterial reports on transfusion-associated sepsis indicate that further efforts are needed to increase the safety of blood transfusions in the long term.

Platelet storage duration and its clinical and transfusion outcomes: a systematic review

Background

Platelets (PLTs) are usually stored for up to 5 days prior to transfusion, although in some blood services the storage period is extended to 7 days. During storage, changes occur in both PLT and storage medium, which may lead to PLT activation and dysfunction. The clinical significance of these changes remains uncertain.

Methods

We performed a systematic review to assess the association between PLT storage time and clinical or transfusion outcomes in patients receiving allogeneic PLT transfusion. We searched studies published in English between January 2000 and July 2017 identified from MEDLINE, Embase, PubMed and the Cochrane Libraries.

Results

Of the 18 studies identified, five included 4719 critically ill patients (trauma, post-cardiac surgery and a heterogeneous population of critically ill patients) and 13 included 8569 haematology patients. The five studies in critically ill patients were retrospective and did not find any association between PLT storage time when PLTs were stored for up to 5 days and mortality. There was also no association between older PLTs and sepsis in the two largest studies (n = 4008 patients). Of the 13 studies in haematology patients, seven analysed prolonged storage time up to 6.5 or 7 days. Administration of fresh PLTs (less than 2 or 3 days) was associated with a significant increase in corrected count increment (CCI) compared to older PLTs in seven of the eight studies analysing this outcome. One single centre retrospective study found an increase in bleeding events in patients receiving older PLTs.

Conclusions

PLT storage time does not appear to be associated with clinical outcomes, including bleeding, sepsis or mortality, in critically ill patients or haematology patients. The freshest PLTs (less than 3 days) were associated with a better CCI, although there was no impact on bleeding events, questioning the clinical significance of this association. However, there is an absence of evidence to draw definitive conclusions, especially in critically ill patients.

Electronic supplementary material

The online version of this article (10.1186/s13054-018-2114-x) contains supplementary material, which is available to authorized users.

The Non-Hemostatic Aspects of Transfused Platelets

Platelets transfusion is a safe process, but during or after the process, the recipient may experience an adverse reaction and occasionally a serious adverse reaction (SAR). In this review, we focus on the inflammatory potential of platelet components (PCs) and their involvement in SARs. Recent evidence has highlighted a central role for platelets in the host inflammatory and immune responses. Blood platelets are involved in inflammation and various other aspects of innate immunity through the release of a plethora of immunomodulatory cytokines, chemokines, and associated molecules, collectively termed biological response modifiers that behave like ligands for endothelial and leukocyte receptors and for platelets themselves. The involvement of PCs in SARs—particularly on a critically ill patient’s context—could be related, at least in part, to the inflammatory functions of platelets, acquired during storage lesions. Moreover, we focus on causal link between platelet activation and immune-mediated disorders (transfusion-associated immunomodulation, platelets, polyanions, and bacterial defense and alloimmunization). This is linked to the platelets’ propensity to be activated even in the absence of deliberate stimuli and to the occurrence of time-dependent storage lesions.