Units Of Random Donor Platelets Research Articles

Thromboelastography-Guided versus Standard-of-Care or On-Demand Platelet Transfusion in Patients with Cirrhosis and Thrombocytopenia Undergoing Procedures: A Randomized Controlled Trial

PurposeTo determine the rate of platelet transfusion in patients with cirrhosis and severe thrombocytopenia (platelet counts <50 × 109/L) undergoing high-risk invasive procedures when prescribed by thromboelastography (TEG) compared with empirical and on-demand transfusion strategies. Materials and MethodsThis was a single-center, single-blinded, randomized controlled trial. Patients with cirrhosis and severe thrombocytopenia undergoing high-risk invasive procedures were randomized into 3 groups: TEG group, transfusions based on TEG parameters; standard of care (SOC) group, 3 units of random donor platelets before procedure; and on-demand group, transfusions based on procedural adverse events/clinician’s discretion. The primary outcome was periprocedural platelet transfusion in each arm. ResultsEighty-seven patients were randomized (29 in each group) with no significant differences in demographics/coagulation profile/procedures. The median platelet count was 33 × 109/L (interquartile range, 26–43 × 109/L). Percutaneous liver biopsy was the most common procedure (46, 52.9%). Significantly lower number of patients in the TEG group received platelets (4 cases, 13.8%; 95% CI, 3.9–31.7) compared with SOC group (100%; 95% CI, 88.1–100; P < .001). Four patients in the on-demand group received platelets (13.8%; 95% CI, 3.9–31.7). Minor (World Health Organization [WHO] Grade 2) procedure-related bleeding occurred in 3 (10%; 95% CI, 2.2–27.4) patients in the TEG-guided transfusion group compared with 1 (3.4%; 95% CI, 0.1–17.8) patient each in the SOC and on-demand groups (P = .43), although the study was not powered for comparison of bleeding rates. No bleeding-related mortality was observed in any of the 3 groups. ConclusionsTEG-prescribed transfusion reduced prophylactic transfusions in patients with cirrhosis and severe thrombocytopenia undergoing high-risk invasive procedures. The study was not powered for comparison of bleeding rates.

First Case Report of Mortality Post Manual Small Incision Cataract Surgery in a Known Case of Immune Thrombocytopenic Purpura

ABSTRACT We present the first case of death due to profuse bleeding from the wound margin following manual small incision cataract surgery (SICS) in a known case of immune thrombocytopenic purpura (ITP), a rare outcome in a common case. A 62-year-old male patient presented with profuse bleeding from the surgical wound of the left eye for 2 days following manual SICS. He was a known case of ITP with a history of gastrointestinal bleeding for which he was admitted few years back but had discontinued prescribed medications and did not mention this medical history to the concerned ophthalmic surgeon before surgery. His platelet count was 5000/mm3 on admission. The patient was admitted to the general medicine ward and was infused with 8 units of random donor platelets and started on injectable high-dose corticosteroids. Despite prompt interventions, the patient succumbed to profound bleeding and multiorgan failure. This case report underscores the importance of comprehensive preoperative evaluation, especially in patients with known bleeding disorders or a history of bleeding complications. While routine cataract surgeries may not typically require extensive preoperative testing as commonly used techniques these days are bloodless and sutureless, certain high-risk patients, such as those with ITP or other bleeding disorders, warrant thorough screening to assess the patient’s hemostatic status accurately to identify and mitigate any adverse outcomes.

Utilization pattern of blood and its components in a tertiary care super speciality hospital

Background: Blood is the most precious gift for human life. Blood transfusion services play a vital role in managing health care services. There is no substitute for blood and its components till date, therefore blood donation drive is very crucial. The primary responsibility of blood transfusion services is to provide safe, sufficient and timely supply of blood and blood products. There has been shift for usage of blood and blood components from the use of whole blood so that maximum utilization of this precious resource could be done. Aim and objectives was to study pattern of utilization of blood and blood components in a super speciality hospital with the indications for transfusions for different components during the study period.Methods: This retrospective study for 12 months (January 2019- December 2 019) on pattern of utilization of blood components was carried out in the department of immunohaematology and transfusion medicine in a super speciality hospital.Results: There were total of 90237 transfusions which were carried out during the study period of 12 months. During the study period, 366 stored whole blood units, 55300 Packed RBC units, 19111 FFP units, 14298 Random Donor Platelet units, 1119 single donor platelets and 43 cryoprecipitate units were issued for use in patients admitted to our hospital.Conclusions: Periodic review and audit of blood component usage becomes essential to assess the blood utilization pattern in any hospital.

Optimizing the Use of Platelets in a Single Oncology Center during Critical Shortages: Can Current Platelet Donations from Volunteer Donors be Sustained to Provide Adequate Platelet Inventories Long Term?

Introduction: The single largest use of platelets transfusions (PLT) are for patients with hematologic malignancies receiving Myeloablative chemotherapy or undergoing hematopoietic stem cell transplantation (HSCT). Patients routinely get prophylactically platelet transfusions at platelet counts ≤ 20 × 109/L at our institution per institutional guidelines. For this review we analyzed a two day period when a critical shortage of platelets occurred to illustrate how we managed the transfusion needs of our patients. Method All daily platelet orders are triaged. The orders are inclusive of patient demographics, indication(s) for transfusion and pertinent lab results (most recent H/H, PLT count, PT/INR/PTT, fibrinogen, D-Dimer, Creatinine and BUN). The location of the patient and indications (ICH Hemorrhage/coagulation abnormalities) further allows the Blood Bank to prioritize the release of platelets. The orders are sorted by counts ≤5K, 6-10K, 11-20K, 21-30K, 31-40K, 51-60K and &amp;gt;61K and then categorized by location (EC, Surgery/Outpatients and disease (Hematologic malignancies/HSCT/other neoplasms). A reduction of the Random Donor Platelet (RDP) inventory by 50% is considered critical especially when daily shipments from our contracted blood suppliers are delayed or reduced. Our regular platelet inventory consist mainly of RDPs with 5-10% of Single Donor Apheresis platelets (SDPs). Our daily transfusion needs consists of 400 to 700 RDPs with a reduction on weekends. Due to the volume of our daily platelet transfusion our needs cannot be met by SDPs only. Results: We received 269 platelet transfusion orders within the two day critical shortage period. The bulk of the orders were received between 4-10 am. The majority (93%) were from patients undergoing treatment for hematologic malignancies of which 18% were from HSCT patients. A total of 474 RDP were transfused to 176 (66%) patients, median of 3 (range 2-4 pooled RDPs), 57 (32%) received 2 pooled RDPs, 116 (66%) received 3 pooled RDPs and 3 (2%) patients received 4 pooled RDPs. Of the 269 patients 82 (30%) were transfused with SDPs. There were 2 duplicate orders and 9 (3.3%) patients did not receive platelets on the requested day. The majority of the platelet orders (85.5%) were for platelet counts =&amp;lt;20 K/uL, followed by Intracranial hemorrhage (4%), active bleeding (3.4%) and bone marrow biopsy (2.6%) and LP/Solid Organ biopsy/Spinal Surgery/Others (each &amp;lt;1%). The reduction in the number of pooled RDPs did not lead to adverse events. Discussion: When the platelet inventory is at par, patients receive 4 pooled RDP units as prophylactic transfusion for counts ≤ 20K. When the inventory falls to below 50% of par, the number of pooled RDPs is decreased to 3 for actively bleeding patients and for those with counts ≤10 K/L. The pools are further decreased to 2-3 RDP units for counts 11-20 K based on inventory. Electronic notification is sent to primary providers to call the Transfusion Medicine Physician when the reason for transfusion does not meet institutional guidelines. The current platelet stock management is heavily dependent on whole blood donations from which RDPs are processed. High school students currently contribute 10% of the US blood supply which may increase up to 20% during the spring/fall months. The most important question that needs to be discussed and addressed before it leads to a crisis is the sustainability of Platelets donations from volunteer donors. Donor Centers around the United States have seen a gradual decline in volunteer donors with aging of the volunteer donor pool. Only 4-6% of eligible donors in the US currently donate blood and this is projected to decrease in the next five years. The TRALI mitigation strategy eliminated many eligible females from donating whole blood/platelets and now the Iron mitigation strategy will also impact the volunteer donor pool. One avenue that could be explored for platelet acquisition would be to accumulate a dedicated pedigreed/trusted pre-screened repeat pool of paid donors similar to the concept used by US plasma centers. This will be a major paradigm shift, be problematic in the beginning as the model is not being used currently in the US for platelet donations. However, with the ever increasing need for platelet transfusion, altruistic appeals alone may be insufficient to meet the demands of blood and platelets. This concept may not be too farfetched in the near future and begs to be considered. Disclosures No relevant conflicts of interest to declare.

Study of Bone Marrow Response to Platelet Transfusion in Severe Traumatic Brain Injury Patients

Introduction: SevereTraumatic Brain Injury (TBI) patients are predisposed to secondary brain insults due to thrombocytopenia and coagulopathy, warranting platelet transfusion. Thrombopoietin (Tpo) has been shown to be a physiological regulator of thrombopoiesis. An inverse correlation between Tpo and the circulating platelet has been previously reported for several clinical conditions. Response pattern of Tpo to circulating platelets in TBI patients has not been studied yet. We hypothesised that in severe TBI patients thrombopoiesis response to TPO will be impairedMethodology: Plasma Tpo levels were measured by enzyme-linked immunosorbent assay was measured 3 times i.e. Pre-platelet transfusion of platelets,24h and 48h post-transfusion in 100 severe (GSC≤8)TBI patients. Platelet transfusion response was evaluated and defined as a ≥20% increase in platelet count from baseline and patients were categorized as responders and non-responders to platelet transfusion.Results: Platelet count was low at admission (89.4±31.1*103 per cumm). Less than 2 units of random donor platelets(RDP) was given to 14% patients,67% patients required2-4 units of RDP and 19% required >4 units of RDP. TPO levels decreased 24h post transfusion compared to pre transfusion (Mean±SD)(127.8±90.2 vs. 142.2±82.6 pg/ml; P 0.07), but elevated at 48h (209.1±74.8 pg/ml; p Pre vs. 48h 0.05). On Average the platelet count improved after transfusion at 24h to 112.7±74.6pg/ml (p Pre vs. 24h 0.003) and continued to rise at 48 h (123.7±82.1 pg/ml; p Pre vs. 48h 0.02). Platelet count and TPO levels were found to be independent (rho -0.12, p 0.38). 62% showed a ≥20% increase in platelet count from baseline (Responders), 38% were non-responders. As significant increase in 24 h post transfusion Tpo levels were seen in responders [median (IQR)] [173.6(0-202.4) pg/ml vs. 164.3(137.1-203.7) pg/ml; p 0.04] compared to pre transfusion levels. Tpo levels in Non-responders did not vary post platelet transfusion [156(0-198.11) pg/ml vs. 158.88(0-198.11) pg/ml; p 0.97]. 28% of Non-responders had low (<81.25 pg/ml) and 2.8% had high (>237.7 pg/ml) pre transfusion Tpo levels. At 24 h post transfusion 26.6% had low and zero had High Tpo levels.Conclusion: In the present study platelet transfusion response inversely correlates with Tpo levels, as 24h post platelet transfusion Tpo levels were transiently low but insignificant and elevated at 48h post transfusion. In non-responders, the post transfusion TPO levels were not sufficient to mitigate the low platelet counts. Hence, the possibility of transient bone marrow depression in severe TBI patients is suggested, which requires further analysis in a larger study cohort. DisclosuresNo relevant conflicts of interest to declare.

Perioperative Haemostatic Management in a Patient Undergoing Craniotomy for Excision of Meningioma: Role of Thromboelastography

Although there is a general predisposition towards hyper-coagulability during brain tumour surgery, hypocoagulability may exist in certain cases even before surgery, detectable only when the physical characteristics of clot formation are studied by viscoelastic point-of-care tests like thromboelastography (TEG). Herein we present a case of a 66-year old male patient with left frontal convexity meningioma, scheduled for craniotomy and excision of tumor. Patient’s preoperative coagulation profile (as assessed by conventional tests) was within normal limits but he was bleeding profusely from the beginning of the surgery and there was massive bleeding during tumour resection. Based on findings of TEG which revealed a severe hypocoagulable picture (low α angle, MA value and CI value with high K value), 10 units of cryoprecipitate and 4 units of random donor platelets were transfused intra-operatively in addition to 2 units of PRBCs. Haemodynamic stability was achieved and subsequent intra-operative course was better. One more unit of PRBC was transfused in the immediate post-operative period and a repeat TEG after 4 hours showed a trend towards normalization of TEG parameters suggesting a restoration of coagulation competency which also correlated with improved clinical condition of the patient.

Utility of Fluorescence Cytometric Cross-Matched Platelets in Severely Alloimmunized Patients

▪Introduction:Platelet refractoriness due to alloimmunization (AI) is associated with increased bleeding, longer hospitalization, higher costs, and delay of therapy in oncologic patients. Platelet refractoriness in AI patients is traditionally managed by using commercially-available cross-match compatible and/or HLA-matched platelets. Our HLA laboratory has developed a fluorescence cytometric-based XM (FCXM) for patients with severe AI and platelet refractoriness for whom HLA compatible platelets were not available. We present a retrospective analysis of the utility of FCXM in oncologic patients who are refractory to random single donor apheresis platelet transfusions.Methods:Patients with platelet refractoriness during 2015 to 2016, as determined by platelet increments <10,000, and having HLA Class I antibodies with a Calculated Panel Reactive Antibody (cPRA) >90%, were selected for study. Data collected include gender, age, diagnosis, ongoing treatment and underlying medical illness during hospitalization, complications, time of release of unit from the Blood Bank, and time of platelet count post-transfusion. Platelet counts increments within 0-1 hour and 1-2 hours after transfusion were recorded. Platelet increments from random-donor platelet units served as controls for FCXM platelet unit increments for the same patient. Statistical analysis was performed using an unpaired t test.Results:We identified 36 patients with platelet refractoriness, of whom 5 met our study criteria (cPRA >90%): 4 female, 1 male. Median age was 67 years (range 48 to 78), with 4 Caucasians and 1 African American. Underlying diagnoses were multiple myeloma (2), colon cancer (1), acute myelocytic leukemia (1), and myelodysplastic syndrome (1). Two out of 5 patients had significant bleeding, 4 out of 5 had sepsis and mucositis (Table 1). All units were leukocyte-reduced, single donor apheresis platelets. The mean number of FCXM testing performed was 3 (8 units each, 24 total) with 13 and 9 units that were compatible and less compatible identified, respectively. The mean platelet increment within 0-1 and 1-2 hour of transfusion for FCXM vs non-FCXM were 9.5 and 7.2 (p= 0.78), and 8.4 vs 5.8 (p= 0.7), respectively. While a trend existed, the small numbers in the study were insufficient to demonstrate statistical significance (Table 2). One patient died during hospital admission due to diffuse pulmonary hemorrhage post induction chemotherapy. Although 1 other patient had significant bleeding, the remaining four patients were able to complete their planned chemotherapy.Conclusion:An overall increase in platelet counts occurs with FCXM identified compatible platelet units in severely AI patients who were refractory to random single donor apheresis platelet units. Although the mean increment using FCXM platelets was < 10,000 and did not differ statistically from the non-FCXM group, we were able to identify units to transfuse patients during chemotherapy and help prevent/treat major bleeding complication and death in 4/5 patients. FCXM testing may be a viable option for identifying compatible platelet units in severely AI patients. [Display omitted] [Display omitted] DisclosuresNo relevant conflicts of interest to declare.

Intravenous Anti-D immunoglobulin for control of life threatening bleed in dengue hemorrhagic fever with severe thrombocytopenia

We report an eight-year-old girl with Dengue Hemorrhagic Fever, shock and a life-threatening upper gastrointestinal and pulmonary bleed with refractory thrombocytopenia. She received 6 units of random donor platelets, 1 unit of single donor platelets, 1 unit of packed red cells and 4 units of fresh frozen plasma to control bleeding but had no response. Finally, 36 hour after onset of bleed intravenous Anti-D 75 μg/kg was given and she had a dramatic increase in platelet counts and cessation of all clinical bleed. This case report highlights that intravenous Anti-D can be a treatment option in Dengue Hemorrhagic Fever with severe refractory thrombocytopenia and massive bleeding.

Anaesthesia management in a patient with severe idiopathic thrombocytopaenia with antepartum haemorrhage for emergency caesarean section.

Sir, Idiopathic thrombocytopaenic purpura (ITP) commonly occurs in young females of reproductive age group.[1] The major complication of ITP is peripartum haemorrhage. Neonatal thrombocytopaenia or haemorrhage is uncommon. These patients commonly present for anaesthesia management for caesarean section or natural birth. We present the anaesthesia management of a patient with severe chronic ITP with antepartum haemorrhage for emergency caesarean section. A 34-year-old multipara, 36 weeks gestation, known case of ITP, on oral prednisolone and dapsone was posted for emergency caesarean section due to low platelet count (14,000/mm3) with antepartum haemorrhage. She weighed 38 kg. Her pulse rate was 112/min and blood pressure was 138/88 mm hg. Her systemic examination and other investigations were normal. She was administered intravenous (IV) methylprednisolone 1 g and transfused 8 units of random donor platelets (RDP). Pre-operative ultrasonography did not show foetal intracerebral bleed. Anti-aspiration prophylaxis included ranitidine 50 mg and metoclopramide 10 mg. After attaching standard monitoring, two wide bore IV cannulae were inserted. After pre-oxygenating the patient for 3 min, anaesthesia was induced with rapid sequence induction with thiopentone 250 mg and succinylcholine 75 mg, followed by oral intubation. Anaesthesia was maintained with isoflurane in 50% oxygen: Nitrous oxide mixture and intermittent administration of vecuronium as and when required. Tranexamic acid 500 mg was injected slowly. A 2.7 kg baby was delivered within 10 min with APGAR score 9 and 10 at 1 and 5 min, respectively. Fentanyl 100 μg and midazolam 1 mg were injected. Oxytocin 20 U in 500 ml of 0.9% saline was started and IV methylergometrine 0.2 mg was given. Intraoperative haemodynamics was stable. Total blood loss was 1.2 L. The patient was extubated on the table. Post-operative steroids were continued and her platelet count improved. There was no neonatal thrombocytopaenia or haemorrhagic complications. Post-operative pain was managed with pentazocine. Both mother and baby were discharged on day 3. Although the incidence of ITP is 5% among pregnant patients, severe thrombocytopaenia (platelet count <50,000/mm3) is rare.[1] There are autoantibodies against the platelet membrane glycoproteins. Exacerbation of thrombocytopaenia is known to occur in pregnancy and peripartum haemorrhage is very common in these patients.[2] Foetal and neonatal thrombocytopaenia and intraventricular bleed are possibilities but not very common.[2] Management of severe thrombocytopaenia in ITP requires platelet transfusion before surgery. IV immunoglobulins 1 g/kg reduce platelet destruction, but it is expensive and was not available with us.[1,2,3,4,5] Perioperative methylprednisolone 1 g along with pre-operative 8 RDP transfusion covered the perioperative period. Since the surgery was emergency, platelet count was not repeated. Each unit of RDP is assumed to increase the platelet count by 3000–5000 units/mm3. Thromboelastography can help us in this scenario, but it was not available with us. Tranexamic acid, an antifibrinolytic, helps to reduce operative blood loss and blood transfusions.[6] The intraoperative uterine contraction was confirmed with oxytocin and methylergometrine. Non-steroidal anti-inflammatory drugs (NSAIDs) including paracetamol were avoided. No intramuscular injections were given. Post-partum haemorrhage was not seen in our patient. Anaesthesia goals in management of pregnant patient with severe thrombocytopaenia must include institution of general anaesthesia, platelet transfusion preferably single donor to prevent allo-immunisation, IV immunoglobulins or steroids to reduce platelet destruction, maternal and foetal/neonatal monitoring for haemorrhagic complications, abstinence from use of NSAIDs or other platelet lowering drugs and avoidance of airway trauma, nasal intubations and intramuscular injections. The maternal and foetal outcomes are good with appropriate management.

Evaluation of Random Donor Platelets Produced from Buffy Coat Stored for 24h at Ambient Temperature: Should This be Implemented in India?

Whole blood derived platelets are made from platelet rich plasma (PRP) method or buffy coat (BC) method. In India majority of random donor platelets (RDPs) are prepared by PRP method. However, BC method offers the advantage of less platelet activation and fewer WBC contamination. Presently in India RDPs are prepared within 8h of whole blood collection, whereas, in Europe this time limit is up to 24h. Our aim was to evaluate the platelet count, WBC contamination, platelet CD62P expression, and biochemical parameters of RDPs prepared from BC within 8h and within 24h of collection. We prepared 40 units of RDP by the BC method from whole blood stored at room temperature within 8h of collection (fresh BC), and another 40 units from BC stored at 22°C for <24h (stored BC). We analyzed the platelet counts, CD62P expression, WBC counts, glucose levels, pH, PO2, PCO2 in both the groups of RDPs, 24h after respective preparation. The platelet counts from stored BC was higher in fresh BC. CD62P expression was low in stored BC compared to fresh BC. There were no differences of pH, pO2, pCO2 and glucose levels in fresh BC and stored BC. WBC contamination was more in fresh BC. Our study stored BC contained higher platelet counts, less WBC contamination and less platelet activation. We conclude that RDP prepared from stored BC is the better method for RDP production.

Significant bacterial contamination risk reduction with the use of diversion pouch

Significant efforts have been made towards bacterial risk minimization by limiting the chance of bacteria entering into collected blood, detecting its presence and eliminating them by pathogen reduction technology. Improved skin disinfection and the use of diversion pouch are effective upstream measures to reduce the risk of bacterial sepsis. Here we report on our experience with the use of blood bags with diversion pouch. An observational study was performed to compare the bacterial contamination rate for two periods of time, i.e. before and after introduction of diversion pouch into blood bags. The incidence of bacterial contamination was monitored by the existing bacterial surveillance programme using pooled samples from 5 units of random donor platelets underwent aerobic culture in the BacT/ALERT 3D system. Between 1 June 2004 and 31 May 2006 (blood bag without diversion pouch), 50 (0·0213%) out of 234,252 units of random donor platelets were found to have bacteria on culture whereas 15 (0·0057%) isolates out of 262,156 units were found from 1 June 2007 to 31 May 2009 (after diversion pouch was introduced). Overall, there was an 85% reduction in bacterial contaminated risk due to skin flora (P < 0·0001) but an increasing trend of detection of non skin flora such as Streptococcus bovis was noted. Integration of diversion pouch into blood bags to divert the first 30 mL blood during blood collection on top of the current skin disinfection protocol can significantly reduce the risk of bacterial contamination.

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BACKGROUND: Allogenic platelet transfusion plays a major role in the management of thrombocytopenia. The study includes details of platelet transfusion over a period of 6 months from January-2011 to June-2011 at blood bank of Gandhi Hospital. Total number of patients who received were 487 and proportionate use of total units of RDP (Random Donor Platelets) issued from blood bank were as follows; dengue hemorrhagic fever (38%) and remaining for acute leukemia (12%), Aplastic anemia (10%), sepsis (10%), DIC (Disseminated Intravascular Coagulation) (10%), cardiac surgery (10%). In dengue hemorrhagic fever, correlation of platelet count with platelet transfusion and platelet increment have been evaluated.

Increased Platelet:RBC Ratios Are Associated With Improved Survival After Massive Transfusion

Several recent military and civilian trauma studies demonstrate that improved outcomes are associated with early and increased use of plasma-based resuscitation strategies. However, outcomes associated with platelet transfusions are poorly characterized. We hypothesized that increased platelet:red blood cells (RBC) ratios would decrease hemorrhagic death and improve survival after massive transfusion (MT). A transfusion database of patients transported from the scene to 22 Level I Trauma Centers over 12 months in 2005 to 2006 was reviewed. MT was defined as receiving ≥ 10 RBC units within 24 hours of admission. To mitigate survival bias, 25 patients who died within 60 minutes of arrival were excluded from analysis. Six random donor platelet units were considered equal to a single apheresis platelet unit. Admission and outcome data associated with the low (>1:20), medium (1:2), and high (1:1) platelet:RBC ratios were examined. These groups were based on the median value of the tertiles for the ratio of platelets:RBC units. Two thousand three hundred twelve patients received at least one unit of blood and 643 received an MT. Admission vital signs, INR, temperature, pH, Glasgow Coma Scale, Injury Severity Score, and age were similar between platelet ratio groups. The average admission platelet counts were lower in the patients who received the high platelet:RBC ratio versus the low ratio (192 vs. 216, p = 0.03). Patients who received MT were severely injured, with a mean (± standard deviation) Injury Severity Score of 33 ± 16 and received 22 ± 15 RBCs and 11 ± 14 platelets within 24 hours of injury. Increased platelet ratios were associated with improved survival at 24 hours and 30 days (p < 0.001 for both). Truncal hemorrhage as a cause of death was decreased (low: 67%, medium: 60%, high: 47%, p = 0.04). Multiple organ failure mortality was increased (low: 7%, medium: 16%, high: 27%, p = 0.003), but overall 30-day survival was improved (low: 52%, medium: 57%, high: 70%) in the high ratio group (medium vs. high: p = 0.008; low vs. high: p = 0.007). Similar to recently published military data, transfusion of platelet:RBC ratios of 1:1 was associated with improved early and late survival, decreased hemorrhagic death and a concomitant increase in multiple organ failure-related mortality. Based on this large retrospective study, increased and early use of platelets may be justified, pending the results of prospective randomized transfusion data.

Evaluation of platelet transfusion triggers in a tertiary‐care hospital

Our 1100-bed referral hospital uses approximately 12,000 units of random-donor platelets (PLTs) and 1,900 units of single-donor apheresis PLTs per year with a mean of 23 percent outdating. An analysis of patterns of utilization has been undertaken to evaluate practice. Over a 9-month period, data were collected on a total of 1682 transfusion episodes in 464 patients. When the pretransfusion count was greater than 10 x 10(9) per L an attempt was made to identify the specific indications for PLT transfusions such as bleeding. The majority (78%) of PLTs were transfused when the counts were above 10 x 10(9) per L. The mean pretransfusion counts for different services were: bone marrow transplant (BMT) 17.4 x 10(9) per L, hematology-oncology 14.6 x 10(9) per L, the Heart Institute 3 x 10(9) per L, and other services 36 x 10(9) per L. The percentage of transfusions given to patients with a count greater than 10 x 10(9) per L varied by service with 79 percent in BMT, 60 percent in hematology and oncology, 98 percent at the Heart Institute, and 81 percent in other services. Routine monitoring of counts shows a mean increment of 10.2 x 10(9) per L per transfusion. One hour posttransfusion counts, 24-hour posttransfustion counts, and documentation of clinical justification for transfusions was often not available. The data show that most patients who receive PLTs have pretransfusion counts of more than 10 x 10(9) per L and more than one-third have pretransfusion counts of greater than 20 x 10(9) per L. The medical literature supports prophylactic PLT transfusion based solely on the count when the PLT number is 10 x 10(9) per L or less. Above this level additional justification is needed although there are different points of view concerning the appropriate triggers. Our data suggest that there is a need for clear hospital transfusion guidelines and ongoing monitoring of PLT use.

P22 Immunohematologic Monitoring and Blood Component Support in a Major ABO Mismatch Allogeneic Peripheral Blood Stem Cell Transplant Recipient

Background Close clinical and immunohematologic monitoring is essential in ABO mismatch peripheral blood stem cell transplantation (PBSCT) in order to anticipate potential complications and to plan appropriate blood component support throughout the disease course.Case Report We describe here a first case of a ABO incompatible PBSCT from our center‐ a 19‐year‐old male patient of aplastic anemia (O Rh positive) who had a successful HLA matched but major ABO mismatch PBSCT from his sibling donor (A Rh positive). On admission patient's hemoglobin (Hb) was 4.7 g dL−1, platelet count (PC) 12 × 109 L−1, total leukocyte count (TLC) 2 × 109 L−1. Patient was typed as O Rh positive with negative direct coombs test (DCT) and IgM isohemagglutinin anti‐A titer‐512 and anti‐B‐512. In the pretransplant period total number of blood components (recipient type) transfused were 35, 1, and 10 random donor platelets (RDP), single donor platelets (SDP) and packed red cells (PRBC) respectively. On day of transplant patient had Hb 9 g dL−1, PC 20 × 109 L−1, TLC 2.6 × 109 L−1, IgM anti‐A‐32, anti‐B‐16 (due to immunosuppressive regimen) and negative direct and indirect coombs tests (ICT). Adequate dose of peripheral blood stem cells harvested from donor by a continuous cell separator was infused to patient as per the institute protocol. Engraftment occurred on 12th day of transplant. During these 12 days patient received a total of four PRBC (recipient type) and 8, 3 units of RDP and SDP (stem cell donor type) respectively. After the engraftment patient's laboratory parameters were Hb 8.2 g dL−1, PC 40 × 109 L−1, TLC 5 × 109 L−1. Patient received very few transfusions after the engraftment and was discharged with Hb of 9.2 g dL−1, PC 146 × 109 L−1, TLC 10.9 × 109 L−1 and with blood group still O Rh positive. Post‐transplant immunohematological workup was done on a weekly basis for first 3 weeks and then on each outpatient visit. On follow up DCT showed mixed field reaction from 1st week till 3rd week post transplant, which became negative by 9th week. ABO cell grouping changed from O to A and thus a cell‐serum discrepancy was noted by 9th week (cell group A Rh positive and serum group O) and by 16th week his blood group finally changed to A Rh positive with IgM anti‐A‐undetectable, IgM anti‐B‐512 along with negative DCT. Throughout the disease course the patient received irradiated blood to avoid transfusion‐associated graft‐versus‐host disease.Conclusion Our patient had uneventful course with appropriate component support and immunohematologic monitoring during and after the transplant and ABO incompatible stem cell could be transplanted without negative outcome on stem cell engraftment.

Evolution of surveillance methods for detection of bacterial contamination of platelets in a university hospital, 1991 through 2004

Platelet (PLT) bacterial contamination (PBC) is the most common transfusion-associated infection. It is important to understand the impact of interventions addressing this problem. PBC was studied by prospective (active) and transfusion-reaction triggered (passive) surveillance from July 1991 to December 2004. Active surveillance, utilized for 10 years, included bacterial culture of all or 4- and 5-day-old PLTs at issue and intermittent use of Gram stain, pH measurements, and early (24-hr) culture of single-donor plateletpheresis (SDP) units. Active surveillance detected 38 instances of PBC, 7 in SDP units (1:2213) and 31 in random-donor PLT units (1:2090 units, p = 0.89; or 1:418 pools of 5 units, p < 0.001). Contaminants were coagulase-negative staphylococci (CONS; n = 27), Staphylococcus aureus (4), Bacillus cereus (1), Serratia marcescens (2), streptococci (2 S. bovis, 1 S. uberis), and CONS with viridans group streptococcus (1). Only one instance of contamination, caused by Pseudomonas aeruginosa, was detected by passive surveillance, with fatal outcome. Colony counts of contaminants ranged from 0.5 x 10(2) to 4 x 10(11) colony-forming units per mL at time of issue. PBC was interdicted before transfusion in 6 cases through Gram stain screening. Transfusion reactions occurred in 13 of 32 recipients (41%), with 9 severe reactions (28%) and 3 deaths (9%). pH testing failed to detect 5 contaminated units and resulted in discard of nearly 2 percent of units, whereas culture of SDP units at 24 hours failed to identify a contaminated unit. Improved active surveillance methods for detecting PBC are needed to improve the safety of PLT transfusions.

Safety of Central Venous Catheter Removal in the Setting of Thrombocytopenia and Peripheral Blood Stem Cell Collection.

Thrombocytopenia is not uncommonly seen in patients undergoing peripheral blood stem cell collection. It is most likely secondary to the administration of chemotherapy and G-CSF, as well as the apheresis process itself. Peripheral blood stem cell collection causes a variable loss of platelets, which are collected along with the mononuclear cells. The ensuing thrombocytopenia can be at times severe, but the bleeding risk in this setting is unclear, as is the need to administer platelets prophylactically when the central catheter used for collection is removed. In this study we retrospectively analyzed data on 40 patients who had a central venous line removed immediately after their last autologous stem cell collection and had a platelet count of less than 50000/μL before the apheresis procedure. Patients were divided into two groups, according to whether or not they had received a platelet transfusion. The expected pre-catheter removal platelet count was calculated, according to the patient's blood volume, the number of platelets in the stem cell product and the amount of platelets transfused in random donor platelet units (RDP) equivalents. Each chart was reviewed for the occurrence of catheter removal-associated bleeding. The results are shown in table 1. Post-apheresis platelet measurement is not routinely performed, due to its inconvenience to the patient and delay in catheter removal. Most clinicians use the pre-apheresis value as a guide to transfuse platelets before taking out the central line. As shown in table 1, in spite of significantly lower measured platelet counts before the harvest procedure in the transfused group, the calculated final counts were similar, due to the transfusion of allogeneic platelets. The patients' weight was significantly lower in the transfused group, and this might actually have contributed to their lower platelet counts after repeated peripheral stem cell collections. There was no bleeding associated with catheter removal in either group. One patient had persistent oozing at the catheter insertion site, likely secondary to an unusually large incision. Removal was uneventful however. In this study, removing the central venous catheter was performed safely without platelet transfusion in patients who had a pre-apheresis platelet count above 30000/μL. It might be safer to administer prophylactic platelet transfusions to patients with lower counts.Table 1Untransfused groupTransfused groupPN346Patient weight in kg (median, range)93 (52–125)76 (63–89)0.03Measured platelet count pre-apheresis X 1000/μL (median, range)40 (28–49)24 (19–30)<0.01Number of platelets removed X 1011 (median, range)0.51 (0.05–1.44)0.48 (0.14–2.34)0.58Number of transfused RDP equivalents per patient (median, range)05 (4–6)-Calculated platelet count post-apheresis (median, range)32 (19–44)39 (8–45)0.56Number of bleeding episodes00-

Thromboelastographic (TEG) Characterization of Patients with Hematologic Malignancy and Chemotherapy Induced Thrombocytopenia (CIT).

The decision to provide prophylactic platelet transfusions to patients with hematologic malignancy and chemotherapy induced thrombocytopenia (CIT) is often based solely on the platelet count being below a somewhat arbitrary threshold. The ability to rapidly assess the overall (net) coagulation status (thrombotic and hemorrhagic tendencies) of these patients may help limit transfusion to those with a measurable bleeding tendency and reduce overall platelet product consumption. We performed pre- and post-platelet transfusion whole blood thromboelastography (TEG) in 20 pts with leukemia (16) or lymphoma (4) and CIT. Citrated venous blood was obtained prior to and 1 hour after single transfusions of 5 units of random donor platelets. Normal ranges were derived from TEG evaluation of 18 normal controls. Correlation between absolute and % changes in maximum TEG amplitude (MA, mm) and time to initial clot formation (R, min) and absolute and % changes in platelet count was assessed. Pts were defined as normal if MA = 45.7 to 64.9 and R = 8.3 to 19.9; hypocoagulable if MA<45.7 and/or R>19.9; hypercoagulable if MA>64.9 and/or R<8.3; and “mixed” for all other result patterns. Pre-transfusion TEG revealed 17/20 (85%) patients to be hypocoagulable, 1/20 (5%) to be hypercoagulable, and 2/20 (10%) to have a mixed pattern. All hypocoagulable patients had a baseline MA<45.7 and 12/17 had an R>19.9. Pre-transfusion platelet count correlated with baseline MA (r =.47, p=.038). No statistically significant correlation between absolute and % change in platelet count and absolute change in MA, % change in MA, absolute change in R, and % change in R existed. Post transfusion, 17/20(85%) patients had normal MA. Post transfusion, 7/17(41%) hypocoagulable patients had normal TEG, 7/17(41%) remained hypocoagulable, and 3/17(18%) became hypercoagulable. Both “mixed” patients became hypercoagulable; the hypercoagulable patient became normal. 3/5 patients with poor transfusion response (platelet count increase < 10,000/mL) went from hypocoagulable to normal while the remaining 2/5 had MA but not R normalization. Based on our TEG data, 15% of hematologic malignancy patients with CIT did not have a baseline hypocoagulable pattern and may not have needed platelet transfusion. In the 85% who were hypocoagulable at baseline, 41% remained hypocoagulable despite platelet transfusion and may have benefited from additional hemostatic therapy. The patients that normalized did so with variable and at times minimal increases in platelet count. The 18% of baseline hypocoagulable patients that became hypercoagulable post-transfusion may have become transiently prone to thrombosis. Our data supports further evaluation of surrogate markers of overall hemostatic potential, like TEG, as a means of guiding and optimizing platelet transfusion practices.

Effects of DMSO on platelet functions and P-Selectin expression during storage

Recent studies suggested that the expression of P-Selectin on stored platelets is related to in vitro activation and loss of viability. We examined the effects of dimethylsulfoxide (DMSO) on in vitro function and P-Selectin expression of platelet concentrates. Fresh random-donor platelet units ( n=60) were divided into four equal groups. A DMSO-free group was chosen as a control. DMSO (0.5%, 1.0% and 3.0%) was added to the other three groups. The samples were stored on a horizontal shaker at room temperature. Biochemical, morphological and platelet function tests and P-Selectin expression were monitored during storage. In all groups, P-Selectin expression, lactate and LDH levels, mean platelet volumes and PO 2 increased but the aggregation response to agonist, the recovery response to hypotonic shock, platelet count, glucose level, pCO 2, and HCO 3 decreased during storage. In DMSO-containing groups, the P-Selectin expression which is a predictor of in vitro activation, was found significantly less often than in the DMSO-free group.

Stability of platelet and plasma HLA concentrations in healthy adults or random-donor platelet concentrates.

The quantitative differences between the platelet HLA antigens of different individuals are potentially significant in determining the survival of transfused platelets in allosensitized patients. To learn whether platelet HLA concentration is sufficiently stable to be documented for each donor and used for donor selection, platelet and plasma HLA concentrations in five healthy adults were measured monthly for 5 consecutive months. HLA concentrations were measured by using a competitive enzyme-linked immunoassay. The results showed that both platelet and plasma HLA concentrations varied within +/- 20 percent of the mean values in each individual. Changes in plasma and platelet HLA concentrations were also studied in 5 units of random-donor platelets during in vitro storage. HLA concentrations were determined every other day over a 5-day period. There was no significant quantitative change in the platelet and plasma HLA concentrations during the 5 days of in vitro storage. Thus, platelet HLA concentrations in healthy individuals are stable and may be quantitatively documented for donor selection.