Adverse events in platelet apheresis donors: A multivariate analysis in a hospital-based program

Lateral ST-elevation myocardial infarction after donation of COVID-19 convalescent plasma in a naïve donor

A 34-year-old man presented with central chest pain heralded by bilateral arm numbness, tingling and pain soon after donation of 1000 mL of COVID-19 convalescent plasma (CP). ECG showed ST-elevation in lateral leads and coronary angiogram showed large thrombus in diagonal branch of the left anterior descending artery. The patient underwent successful thrombus aspiration and percutaneous coronary intervention of diagonal branch. In this report, we describe a case of coronary thrombosis leading to ST-elevation myocardial infarction in a naïve plasma donor after donation of COVID-19 CP.

Rapidly Establishing a Hospital-Based Convalescent Plasma Collection Center With the Alyx Apheresis Collection Device

The effort to collect convalescent plasma from individuals who recovered from COVID-19 began in earnest during the spring of 2020. Either whole blood or apheresis donations were obtained, the latter yielding higher numbers of units per donor per collection and more frequent collections. The NorthShore University HealthSystem blood donor center purchased 2 Alyx (Fresenius Kabi) apheresis plasma collection devices and quickly implemented them in order to collect COVID-19 convalescent plasma. Apheresis-experienced and inexperienced phlebotomists operated the instruments. Donors were collected >14 days from symptom resolution and all donors were negative by SARS-CoV-2 nasopharyngeal swab. Both internal metrics of performance as well as a post donation survey were used to evaluate the feasibility implementing this collection program. During the first 100 days of the collection program, 650 plasma units were collected. In particular, during the first week of the program, 38 units were collected and distributed to hospitals under the emergency investigational new drug and expanded access program. Fifty-one donors (15%) were deferred due to vital signs out of range or donor screening questions. Thirty-one donors (10%) were deferred due to positive nasopharyngeal swab. Lower than target yield occurred in 16.6% of collections due to donor reactions or flow errors. Donors rated the overall program lower, but not the staff, when they reported symptoms related to collection. In conclusion, a hospital-based apheresis convalescent plasma collection program can be rapidly implemented. Donor reaction rates and vein infiltration rates should be carefully monitored for each phlebotomist.

Extreme Levels of Platelet Count in Essential Thrombocythemia: Management and Outcome, Report of Two Cases

Myeloproliferative neoplasms including essential thrombocythemia (ET) is usually caused by somatic mutations in multiple genes, including the JAK2 (most frequently), CALR gene, and MPL. In rare cases, the disease is caused by other mutations such as THPO or TET2 gene; however, around 10–15% with ET might have triple-negative mutations. Here we present 2 cases of ET who were asymptomatic on diagnoses, but found to have extremely high platelet counts as never reported earlier. The management and treatment plan can be a challenging step. The objective is to draw attention to the early introduction of thrombocytapheresis in the management of such patients given its notable outcomes.

Effect of Frequency of Platelet Apheresis on Coagulation Function in Donors: A Prospective Cohort Study

The maximum number of plateletpheresis donation was permitted up to 24 times every year for each donor in China. This study was investigated the effect of donation frequency on coagulation function of the plateletpheresis donors. A total of 96 plateletpheresis regular donors (splitted into A, B, C groups with 32 donors each group. A was 6–11 times donations, B with 12–17 times and C with 18–24 times) and 32 first time plateletpheresis donors (D group) were analyzed. The coagulation reaction time (R), blood clot formation time (K), α-Angle, normal maximum amplitude (MA) were tested using thromboelastography instrument. Platelet (PLT) count was measured using a hematology analyzer. The ratio of the male to female were 23:9, 24:8, 27:5 and 24:8, the mean age were 40.7 ± 7.6, 39.8 ± 8.3, 40.2 ± 7.9 and 37.0 ± 9.3, and the platelet collection amount were 1.55 ± 0.37 U, 1.58 ± 0.38 U, 1.61 ± 0.33 U and 1.46 ± 0.31 U in the A, B, C, D groups respectively. There were significant difference in the values of the R, K, α-Angle, MA and PLT count between before and after plateletpheresis donation in each group (p < 0.05). However, the values of R, K, α-Angle, MA and PLT count in the before donation were not difference among the A, B, C, D groups (p > 0.05). Similar results were found in the after plateletpheresis donation. The number of the PLT was significantly correlated with the values of the R, K, α-Angle and MA (p < 0.05). However, the frequency of plateletpheresis were not significantly correlated with R, k, α and MA parameters (p > 0.05) using Spearman correlation analysis. The regular donation of apheresis platelets and the frequency of annual blood donation had no adverse effect upon coagulation function of the donors in China.

Does plateletpheresis induce a hypercoagulable state? A global assessment of donor's hemostatic system by ROTEM

Since there is still debate on the effects of plateletpheresis on coagulation system, we aimed to perform a global assessment of donor's hemostatic function undergoing plateletpheresis by rotation thromboelastometry (ROTEM) analysis and to clarify if plateletpheresis procedure induces a hypercoagulable state. Thirty male plateletpheresis donors were included in the study. Four blood samples were drawn at different time intervals: before the beginning of the apheresis procedure; immediately after the completion of the apheresis procedure; 24 h and 7 days after the apheresis procedure. "Hypercoagulability" was diagnosed readily by having an accelerated clot formation, as evidenced by shortening of CFT and an increase of the clot strength, as evidenced by increasing of MCF. In INTEM assay, CFT value after apheresis was significantly prolonged compared with baseline value while CFT value 7 days after apheresis was significantly shortened compared with values immediately and 24 h after apheresis (p < 0.001). However, CFT-INTEM still did not show any shortening in any of the measurements when compared to pre-apheresis value. MCF value after apheresis was significantly shortened compared with baseline value while MCF value 7 days after apheresis was significantly prolonged compared with values immediately and 24 h after apheresis (p < 0.001). However, MCF-INTEM still did not show any increase in any of the measurements when compared to pre-apheresis value. There was no significant difference in CT value between four measurements (p = 0.064). In EXTEM assay, CFT value after apheresis was significantly prolonged compared with baseline value while CFT value 7 days after apheresis was significantly shortened compared with values immediately and 24 h after apheresis (p < 0.001). However, CFT-EXTEM still did not show any shortening in any of the measurements when compared to pre-apheresis value. MCF values immediately and 24 h after apheresis were significantly shortened compared with baseline value while MCF value 7 days after apheresis was significantly prolonged compared with values immediately and 24 h after apheresis (p < 0.001). However, MCF-EXTEM still did not show any increase in any of the measurements when compared to pre-apheresis value. We found no differences in CT value between four measurements (p = 0.208). Since ROTEM tracings on both INTEM and EXTEM assays did not reveal any significant shortening of CFT and increasing of MCF in any of the measurements after apheresis procedure, we concluded that plateletpheresis does not induce a hypercoagulable state in healthy donors.

Haemostatic parameters, platelet activation markers, and platelet indices among regular plateletpheresis donors

OBJECTIVE

Plateletpheresis is generally a safe procedure for platelet donation. Studies on the effects of haemostatic parameters and possible association between automated plateletpheresis and hypercoagulable state are limited. Hence, this study aimed to investigate the effects of plateletpheresis on regular donors using haemostatic parameters, i.e. natural anticoagulant proteins, platelet indices, and platelet activation markers.

METHODS

A total of 139 participants (plateletpheresis donors and normal controls) were recruited and divided into two groups: Group 1 participants who underwent tests for haemostatic and platelet indices and Group 2 participants who underwent tests for platelet activation markers using CD62P and PAC-1 monoclonal antibodies.

RESULTS

A significant mild shortening of prothrombin time and platelet activation were demonstrated (by increased CD62P and PAC-1 markers) among regular plateletpheresis donors as compared to healthy controls. The current pre-donation platelet count of plateletpheresis donors was significantly lower than their mean baseline platelet count obtained before their first plateletpheresis procedure. However, no significant differences were observed for the other platelet parameters (platelet count, mean platelet volume, platelet distribution width, activated partial thromboplastin time, protein C, protein S, antithrombin, and von Willebrand Factor antigen) between plateletpheresis donors and healthy controls.

CONCLUSION

This study concludes that regular plateletpheresis is a safe procedure. A possibility of mild platelet activation among regular donors requires further confirmation. However, pre-analytical platelet and FVII activations could occur in vitro contributing to these findings.

Donor Safety in Haemapheresis: Development of an Internet-Based Registry for Comprehensive Assessment of Adverse Events from Healthy Donors

BACKGROUND

Currently, there is an extensive but highly inconsistent body of literature regarding donor adverse events (AEs) in haemapheresis. As the reports diverge with respect to types and grading of AEs, apheresis procedures and machines, the range of haemapheresis-related AEs varies widely from about 0.03% to 6.6%.

METHODS

The German Society for Transfusion Medicine and Immunohaematology (DGTI) formed a 'Haemapheresis Vigilance Working Party' (Arbeitsgemeinschaft Hämapheresevigilanz; AGHV) to create an on-line registry for comprehensive and comparable AE assessment with all available apheresis devices in all types of preparative haemapheresis: plasmapheresis (PLS), plateletpheresis (PLT), red blood cell apheresis, all kind of leukaphereses (autologous/allogeneic blood stem cell apheresis, granulocyte apheresis, lymphocyte/monocyte apheresis) and all possible types of multi-component apheresis. To ensure the comparability of the data, the AGHV adopted the 'Standard for Surveillance of Complications Related to Blood Donation' from the International Society for Blood Transfusion in cooperation with the International Haemovigilance Network (IHN) and the American Association of Blood Banks for AE acquisition and automated evaluation. The registry is embedded in a prospective observational multi-centre study with a study period of 7 years.

RESULTS

A preliminary evaluation encompassed the time period from January, 2012 to December, 2015. During this time, the system proved to be safe and stable. Out of approximately 345,000 haemaphereses 16,477 AEs were reported (4.9%) from 20 participating centres. The majority of AEs occurred in PLSs (63%), followed by PLT (34.5%) and SC (2.2%). Blood access injuries (BAI) accounted for about 55% of the supplied AEs, whereas citrate toxicity symptoms, vasovagal reactions and technical events (e.g. disposable leakages, software failures) rather equally affected haemaphereses at 8-15%. Out of 12,348 finalized AEs, 8,759 (70.1%) were associated with a procedure-related break-off, with BAI being the prevailing cause (5,463/8,759; 62.4%). An automated centre- and procedure-specific AE evaluation according to the latest IHN standard and AGHV pre-settings is available within a few minutes.

CONCLUSIONS

An on-line electronic platform for comprehensive assessment and centre-specific automated evaluation of AEs in haemaphereses has been developed and proved to be stable and safe over a period of 4 years.

The role of thrombocytapheresis in the contemporary management of hyperthrombocytosis in myeloproliferative neoplasms: A case-based review

Extreme thrombocytosis induces an acquired thrombotic-hemorrhagic diathesis, and left uncontrolled is a harbinger of potentially fatal vascular complications. Currently, cytoreduction with medical therapy remains the mainstay of hyperthrombocytosis management. However, it offers a less-than-ideal option in situations where a rapid reduction in platelets is urgently needed, as in the presence of vital end-organ ischemia or to ameliorate of life-threatening hemorrhage. The role of thrombocytapheresis, or plateletpheresis, in hyperthrombocytosis has become increasingly obsolete given the proactive titration of cytoreductive therapies and early identification and correction of reversible causes of reactive thrombocytosis. Despite its narrowed indications, plateletpheresis continues to offer a valuable temporizing measure in platelet count reduction before cytoreductive agents exert their maximal effect. In this context, it is important for the treating physician to be aware of the symptoms and risks associated with hyperthrombocytosis to inform best clinical practices. In this review, we discuss the role of plateletpheresis in the modern-day management of hyperthrombocytosis in patients with myeloproliferative neoplasms through a case based review of the literature. It becomes apparent throughout the discussion that the decision to perform plateletpheresis should be individualized based upon the clinical scenario, degree of thrombocytosis, available infrastructure and every patient's risk profile.

A Retrospective Analysis of Apheresis Donor Deferral and Adverse Reactions at a Tertiary Care Centre in India

INTRODUCTION

With increasing demand of platelet component each day, blood bank plays a pivotal role in ensuring supply of safe blood as and when required. Plateletpheresis procedure is a relatively simple, safe and important adjunct to blood bank inventory. However, recruitment of healthy blood donors is a challenge that the health industry is facing today.

AIM

To determine the reasons and rates of apheresis donor deferral along with investigation of adverse reactions encountered during the procedure.

MATERIALS AND METHODS

Records of single donor apheresis were retrospectively analysed from 1st January 2010 to 31st December 2014. The study was carried out at Blood Bank, Safdarjung Hospital, New Delhi, India. The donor details that were studied included - age, sex, type of donation (voluntary/replacement/ repeat), reason for donor deferral and type of adverse reaction, if encountered during the procedure.

RESULTS

Among the 478 donors screened for plateletpheresis procedure during a study period of 5 years, 134 (28.03%) were deferred. Temporary deferrals accounted for majority (93.28%) of the deferrals. Low platelet count (50.75%) was the main reason of donor deferral followed by low haemoglobin (20.89%). Amongst the 344 selected donors, 15 (4.36%) had some type of adverse reaction associated with the procedure.

CONCLUSION

We suggest that the selection criteria for plateletpheresis donors should be revised to deal with shortage of apheresis donors. The criteria regarding minimum pre-procedure platelet count (above1.5 lac/μl) and haemoglobin (above 12.5 g/dl) need to be lowered so as to suit the Indian scenario. The lower adverse reaction rates, 14/344 (4.06%) associated with this procedure encourages safety of donors and is important in recruitment of new donors.

Adverse Events During Apheresis Procedures: Audit at a Tertiary Hospital

Apheretic platelets are better quality blood components which reduce donor exposure and chances of TTIs to transfusion recipients when compared to the whole blood derived components. Though safe, these apheretic donations are associated with donor adverse events. We evaluated the incidence of such adverse events associated with the modern apheresis procedures that would provide an insight as well as help formulating preventive steps to avoid frequent occurrences of such events. This prospective audit-based observational study was conducted over 1 year. Donors for plateletpheresis were selected as per the standard operating procedure of the Apheresis Lab. The apheresis procedures were done on the MCS+ (Haemonetics Corp.), Trima Accel (Terumo BCT) and COM.TEC (Fresenius Kabi AG). 1740 apheresis procedures were performed, out of which 1708 were plateletpheresis and 32 therapeutic plasma exchange (TPE) procedures for 7 patients. A total of 102 adverse events were noted; of which, 80 (78.43 %) events were associated with donors, 15 (14.71 %) were owed to equipment related problems and 7 (6.86 %) were technical aberrations. All the events associated with donors were mild. No adverse events were reported with any of the 32 TPEs. Apheresis procedures are associated with adverse events which can be reduced by meticulous donor-vigilance, superior training modules for the technical personnel and continued supervision of experienced transfusion medicine specialists. Continued efforts towards making the donor's experience with apheresis more pleasant give a forward thrust to the noble vision of preparing a voluntary apheresis donor pool in India.

Citrate anticoagulation: Are blood donors donating bone?

An estimated 2.4 million volunteer apheresis blood donation procedures were performed in the United States in 2010, and increases in the proportion of transfused blood products derived from apheresis blood collections have been consistently reported. Anticoagulation is required during apheresis and is achieved with citrate. Donor exposure to citrate causes an acute physiological response to maintain serum mineral homeostasis. Some data are available on the sequelae of this acute response in the days and weeks following exposure, raising questions about bone mineral density in regular apheresis donors. New research is emerging that addresses the potential long-term health outcomes of repeated citrate exposure. This article reviews the acute physiological response to citrate anticoagulation in volunteer blood donors, presents contrasting perspectives on the potential effects of citrate exposure on bone density, and identifies key knowledge gaps in our understanding of long-term health outcomes in apheresis donors. J. Clin. Apheresis 31:459-463, 2016. © 2015 Wiley Periodicals, Inc.

Risk factors associated with the occurrence of adverse events in plateletpheresis donation

Objective

To recognize the profile of platelet donors and the profile of the plateletpheresis session as well as to investigate the main adverse events of platelet donation using plateletpheresis and associated risk factors.

Methods

This retrospective, cross-sectional and analytical study was performed with a quantitative approach by analyzing 316 donation files from February 2010 to December 2011. The IBM SPSS Statistics program was used for data processing and analysis. The chi-square test was used to verify whether there was an association between factors related to the procedure and the donor, and the adverse events that occurred.

Results

The mean age of platelet donors was 40 years old (standard deviation = 8.9), with the prevalent age group being between 40 and 49 years old; the prevalent blood type was O positive (53.8%), the mean duration of the procedure was 73 min and the mean amount of anticoagulant used was 360 mL. The association between procedure duration and the volume of anticoagulant was inverse and statistically significant; the longer the procedure and the greater the volume of anticoagulant used, the less adverse reactions occurred.

Conclusion

The low incidence of adverse events indicates that the procedure is well tolerated by donors. Obtaining data regarding the incidence of adverse events is a way of promoting a dynamic review of medical and nursing teams to improve the safety and comfort of the donor.

Single-donor platelet apheresis: observational comparison of the new Haemonetics Universal Platelet protocol with the previous Concentrated Single Donor Platelet protocol

BACKGROUND

The Haemonetics MCS(®)+ cell separator is a device dedicated to the collection of leucoreduced single-donor platelets. The new Universal Platelet protocol has been introduced to improve the efficiency of apheresis and increase flexibility in the collection of leucoreduced platelets in combination with red blood cells and plasma. In this study we compared its performance with that of the previous Concentrated Single Donor Platelet protocol.

MATERIALS AND METHODS

This observational study had a within-subject design and involved 135 donors who underwent plateletapheresis with both protocols. The primary end-point was collection efficiency; secondary end-points were other performance indices, such as procedure time and collection rate. A satisfaction questionnaire was also administered to the 135 donors to evaluate opinions on duration, comfort and side-effects of donations with the two protocols. For each parameter of interest, we tested the difference between the two protocols within donors, using a one-sample t-test or exact McNemar's test as appropriate.

RESULTS

The collection efficiency of the Universal Platelet protocol was significantly higher than that of the Concentrated Single Donor Platelet protocol (58% vs 47%; p<0.0001). The Universal Platelet Protocol collected more platelets in less time, leading to a higher collection rate (6.5 vs 5.0×10(9)/min; p<0.0001). In general, donors found apheresis with the Universal Platelet protocol of equal duration or faster, of similar or greater comfort and with an equal number or fewer side effects, compared with the Concentrated Single Donor Platelet protocol.

DISCUSSION

Our study endorses the use of the new Universal Platelet protocol in daily transfusion practice since it substantially improves collection efficiency in leucoreduced platelet procedures compared with the Concentrated Single Donor Platelet protocol. This technical improvement seems to be accompanied by equal or greater comfort for the donor.

Adverse events associated with apheresis procedures: Incidence and relative frequency

INTRODUCTION

Apheresis procedures [Plateletpheresis, Plasmapheresis/ Therapeutic Plasma Exchange (TPE), & Peripheral Blood Stem Cell Collection (PBSC)] are usually well tolerated. Occasionally, Adverse Events (AEs) of variable severity may occur during or after the procedure. AEs that occur in Donors/Patients are divided into local reactions and systemic reactions.

MATERIALS AND METHODS

A total of 3,367 apheresis procedures were performed, out of which 3,120 were plateletpheresis procedures, and out of which 1,401 were on Baxter CS 3000 & 1,719 were on Haemonetics MCS+ cell separators. Rest of 247 TPE & PBSC procedures were done on Haemonetics MCS+ cell separators.

RESULTS

90 AEs were reported in relation to the 3,367 procedures. Out of 90 AEs, 85 AEs (94%) were associated with plateletpheresis (n = 3,120) and 05 AEs (06%) with TPE & PBSC (n = 247). The rate of vascular injury (VI), Citrate reaction (CR), and Presyncopal/Syncopal (PS/S) in plateletpheresis was 1.6% (52/3,120), 0.96% (30/3,120), and 0.096% (03/3,120), respectively. The rate of CR in TPE and PBSC was 1.23% (02/162) and 2.3% (02/85), respectively. The rate of PS/S in PBSC was 1.17% (01/85). AEs for Plateletpheresis, TPE & PBSC were 2.7% (85/3,120), 1.23% (02/162), and 3.5% (03/85), respectively. VI, CR, and PS/S were mostly of mild intensity. Both cell separators were equally safe, when AEs associated with plateletpheresis were compared with each other; 2.8% on CS 3000 & 2.6% on MCS+.

CONCLUSION

Apheresis procedures performed on cell separators are safe, with a low incidence of significant AEs. No significant difference was noted in AEs among the two cell separators studied.

Adverse reactions during voluntary donation of blood and/or blood components. A statistical-epidemiological study

BACKGROUND

Voluntary donors normally tolerate blood donation very well, but, occasionally, adverse reactions of variable severity may occur during or at the end of the collection. Aim of this study was to estimate and possibly avoid the cause of unwanted reactions.

MATERIALS AND METHODS

The study was conducted over a period of 6 months, from 24(th) October, 2005 to 24(th) April 2006. The donor population analysed consisted of 4,906 donors (3,716 male and 1,190 female). In total, 3,983 (81%) voluntaries have donated whole blood, 851 (17%) plasma from apheresis, 64 (1.3%) experienced multicomponent donation, and 8 (0.1%) were donors of plasma-platelet apheresis.

RESULTS

Only 63 donors (1.2% of all the volunteers) suffered some kind of adverse reaction: 59 (1.08% of the subjects) had mild reactions (agitation, sweating, pallor, cold feeling, sense of weakness, nausea), and only 4 (3 males and 1 female, 0.2%) had more severe disorders, including vomiting, loss of consciousness, and convulsive syncope.

CONCLUSIONS

Although the number of donors who developed disturbances during or at the end of blood donations was very low, it is nevertheless desirable to reduce risks to a minimum. A set of advices is provided for preventing problems.

Adverse reactions in blood and apheresis donors: experience from two Italian transfusion centres

BACKGROUND

Blood and apheresis donations are widely considered to be safe with a low incidence of adverse reactions and injuries; however, data reported in the medical literature on the prevalence of adverse events in donors and studies on the predictive risk factors for donor reactions are limited and contradictory.

METHODS

From January 2002 to December 2006 we recorded every adverse reaction verified during 240,596 consecutive blood and apheresis donations (183,855 homologous whole blood donations, 6,669 autologous whole blood donations, 38,647 plasmapheresis, 2,641 plateletpheresis and 8,784 multicomponent donations) at the Italian Transfusion Centres of Verona and Ragusa,.

RESULTS

Using a special, pre-arranged form within the quality system, a total of 686 adverse reactions (related to 0.28% of all donations) were recorded. Vasovagal reactions, mostly of mild intensity, were the most commonly observed adverse reactions, with a frequency of 0.20% (487/ 240,596). The frequency of the vasovagal reactions varied according to the different types of donation, being 0.19% (346/183,855) for homologous whole blood donations, 0.24% (16/6,669) for autologous whole blood donations, 0.16% (63/38,647) for plasmapheresis, 0.68% (18/2,641) for plateletpheresis and 0.49 (43/8,784) for multicomponent donations. Citrate toxicity was reported in 0.38% (189/50,072) of apheresis donations. Severe adverse reactions were very rare, as they occurred in 0.004% of the donations (10/240,596).

CONCLUSIONS

In conclusion, the results of our 5-year survey document that apheresis and blood donation are safe procedures for the donor with a low incidence of adverse reactions; the adverse reactions that did occur were mostly mild and resolved rapidly.

Comparison of Plateletpheresis on the Fenwal Amicus and Fresenius Com.Tec Cell Separators

SUMMARY: BACKGROUND: A variety of apheresis devices are now available on the market for plateletapheresis. We compared two apheresis instruments (Fenwal Amicus and Fresenius COM.TEC) with regard to processing time, platelet (PLT) yield and efficiency, and white blood cell (WBC) content. MATERIAL AND METHODS: Donors undergoing plateletpheresis were randomly separated into two groups (either the Amicus or the COM.TEC cell separator). RESULTS: In the pre-apheresis setting, 32 plateletpheresis procedures performed with each instrument revealed no significant differences in donors' sex, age, weight, height and total blood volume between the two groups. However, the pre-apheresis PLT count was higher with the COM.TEC than with the Amicus (198 × 10(3)/μl vs. 223 × 10(3)/μl; p = 0.035). The blood volume processed to reach a target PLT yield of ≥3.3 × 10(11) was higher in the COM.TEC compared to the Amicus (3,481 vs. 2,850 ml; p < 0.001). The median separation time was also significantly longer in the COM.TEC than in the Amicus (61 vs. 44 min; p < 0.001). 91 and 88% of the PLT products collected with the Amicus and the COM.TEC, respectively, had a PLT count of >3.3 × 10(11) (p = 0.325). All products obtained with both instruments had WBC counts lower than 5 ↔ 10(6), as required. There was no statistical difference with regard to collection efficiency between the devices (55 ± 15 vs. 57 ± 15%; p = 0.477). However, the collection rate was significantly higher with the Amicus compared to the COM.TEC instrument (0.077 ± 0.012 × 10(11) vs. 0.057 ± 0.008 × 10(11) PLT/min; p < 0.001). CONCLUSION: Both instruments collected platelets efficiently. Additionally, consistent leukoreduction was obtained with both instruments; however, compared with the COM.TEC instrument, the Amicus reached the PLT target yield more quickly.

The 2000 United Kingdom Haemophilia Centre Doctors' Organisation (UKHCDO) inhibitor guidelines

The UKHCDO inhibitor guidelines address the diagnosis and management of patients with haemophilia A, haemophilia B and acquired haemophilia. Recommendations are based on best current practice as reflected in the published evidence base. Many current treatment strategies are based on uncontrolled observations highlighting the need for well designed controlled studies.

National audit of citrate toxicity in plateletpheresis donors

Citrate toxicity complicating plateletpheresis is not uncommon. However, the scale and severity of the problem have never been formally addressed. In order to answer these questions we undertook a national audit of 13 070-platelet procedures throughout 17 apheresis centres in England over a 3-month period from 1 April to 30 June 2000. A standard form was distributed to each centre to record the symptoms/signs of citrate toxicity which were then graded (grades 1-5) according to their severity. The following variables were studied to determine whether they influenced the frequency and severity of citrate toxicity: 1. The type of manufacturer's cell separator used (Cobe Spectra, Haemonetics, Baxter Amicus and Trima). 2 The type of procedure: single needle, dual needle, single, double or triple dose. 3 The way in which donors were instructed to report symptoms of citrate toxicity.

OUTCOME

Plateletpheresis is a relatively safe procedure provided that donors who experience severe reactions receive appropriate treatment. The incidence of severe citrate toxicity (0.03% procedures) is comparable to that of severe faints following whole blood donation, indicating a comparable margin of safety. Donors should be warned of the symptoms of citrate toxicity at their first attendance only. More frequent reminders encourage donors to over-report symptoms of mild citrate toxicity.