The relationship of platelet yield, donor's characteristic and apheresis instruments in China

Incidence and severity of adverse events among platelet donors: A three-year retrospective study

Adverse events (AEs) are unfortunate consequences of platelet donation. This study reports the incidence and severity of AEs and the associated risk factors in platelet donation at a major blood donation center in Riyadh, Saudi Arabia.A review of donation records was conducted between 2014 and 2017. Eligible study participants were 5007 platelet donors who had donated 7969 times. Each donation was accounted for as a single study subject. Participants' characteristics were described and analyzed as potential contributing factors to adverse events.The average age of platelet donors was 30.0±7.3 years. First-time donors comprised (n = 3,100, 61.9%) of the sample, and 1907 (38.1%) were multiple donors (periodic/routine). Their average BMI was 28.6 ± 4.9 kg/m2. Most donors have blood type "O" and Rheo "positive". The range of blood volume processed was 0 to 5273 ml, while the procedure duration ranged from 0 to 90 minutes. The average platelet yield was 3.8 ± 3.5 ∗1011 platelets per unit, and the average collected volume was 257.6 ± 86.1 ml. Incidence of AEs was 4.2%, of which 91.3% were mild and 8.7% were severe. AEs were vascular injuries (65.3%), vasovagal reactions (11.6%), and citrate toxicity (5.3%). AEs were associated with first-time donation, adj.OR (95%CI) = 1.5 (1.1-1.8) and lower BMI, adj. OR (95% CI) = 1.4 (1.1-1.8). Citrate toxicity was present in severe forms, unlike vascular injuries and vasovagal reactions that tended to be milder. Donors with hemoglobin levels above 16 g/dl, adj. OR (95% CI) = 1.3 (1.1-1.7) and platelet levels below 250,000, adj. OR (95% CI) = 1.3 (1.1-1.6) were more likely to contract AEs than others.Reporting adverse events is essential to establish a benchmark for the annual incidence rates to be compared against local and international figures. Blood donor centers should also take notice of blood donors characteristics that are associated with higher incidence and more severe forms of AEs during or after platelet donation.

The Play of Citrate Infusion with Calcium in Plateletpheresis Donors

Citrate is the anticoagulant of choice for plateletpheresis. Citrate toxicity is common during plateletpheresis as citrate chelates calcium and causes hypocalcemia in donors. We have conducted this study to analyze the effects of routine citrate infusion during plateletpheresis on laboratory and clinical parameters. We also compared the dose of citrate delivered to donors during plateletpheresis using two different cell separators as Haemonetics MCS + and Trima Accel. The study was conducted on 50 plateletpheresis donors who were eligible for donation. Donor demographics and baseline parameters were recorded. Pre, mid and post-procedure blood samples were collected for hematological and biochemical analysis. We found a significant decrease in baseline iCa (1.23 ± 0.07 mmol/L) from start to mid-procedure (1.19 ± 0.006 mmol/L) which recovered at 30 min post procedure (1.2 ± 0.01 mmol/L). The incidence of citrate toxicity was 10%. In donors with citrate toxicity, the post-procedure recovery of iCa was not seen and there was a further decrease in iCa levels. We also found a significant fall in Hb and platelet count post plateletpheresis. We observed that lower PLT counts (< 200 × 10³/µL) necessitated higher blood volume processing and therefore a higher anticoagulant (citrate) dose. The Trima Accel cell separator reached platelet target yield faster but with a higher citrate dose as compared to Hemonetics MCS + . Ionized calcium decreases significantly during plateletpheresis but recovers soon after the completion of the procedure. Serious adverse events were not observed during plateletpheresis. The mild citrate toxicity which occurred was easily managed by slowing the procedure and administering oral calcium to donors. Trima Accel and Hemonetics MCS + both collected platelets efficiently, with minimal donor discomfort.

The effects of autoflow management on flow-rate alerts, collection efficiency, and collection rate during plateletpheresis

BACKGROUND

In 2018, Trima Accel software version 6.4 with autoflow management released in China. The purpose of this retrospective study was to evaluate the effects of autoflow management on plateletpheresis procedures, specifically concerning flow-rate alerts, collection efficiency (CE), and collection rate (CR).

METHODS

A total of 2526 procedures using Trima Accel version 6.4 from Nov 2018 to Jan 2019 were included as the test arm in this study. Another 2043 procedures using version 5.1.9 from Nov 2017 to Jan 2018 were included as the control arm. We compared the low-flow alerts and no-flow alerts, collection efficiency (CE), and collections rate (CR) between the two study arms. Also, we analyzed the incidence of autoflow increases and autoflow decreases of version 6.4.

RESULT

The incidence of low-flow alerts for test and control was 16.6 % and 55.3 %(χ² = 754.024, p = 0.000), with the maximum number of low-flow signals of 6 and 51, respectively. The incidence of no-flow alerts for test and control was 7.8 % and 45.0 %(χ² = 843.695, p = 0.000), with a maximum of 16 and 27, respectively. The CE of version 6.4 was slightly higher than version 5.1.9 (69.7 ± 6.7 % versus 68.6 ± 7.4 %). Similarly, CR was higher for version 6.4 (7.7 ± 2.1versus 7.0 ± 1.8 × 10⁹/min). For software version 6.4, autoflow increases or autoflow decreases triggered in 99.8 % donors.

CONCLUSION

Autoflow management shows significant advantages in reducing alerts and subsequent manual intervention. We observe a higher CR and CE using Trima Accel version 6.4 than version 5.1.9, which leads to a more efficient platelet collection.

A Study on Influence of Donor Hematocrit on the Procedural Parameters of Concentrated Single Donor Platelets Collected by Two Apheresis Devices

With improvements in apheresis collection, platelet additive solution (PAS) is steadily replacing plasma as the storage medium in single donor platelets (SDP). Concentrating platelets in SDP with one-third of plasma and two-thirds of PAS is referred as Concentrated-SDP (C-SDP). We studied the influence of donor hematocrit (Hct) in C-SDP procedures. A retrospective study, consisting of 124 and 95 plateletpheresis donors in MCS+ and Trima respectively. We compared two apheresis equipments MCS+ and Trima with regard to donor hematocrit on procedural parameters such as collection efficiency (CE), collection rate (CR), yield per hour (Y/H), yield per litre (Y/L) and percentage blood volume processed (%BV) during C-SDP procedures. Donors were categorized into two groups with Group A (Hct ≤ 46%) and Group B (Hct > 46%) based on mean baseline Hct of the study population. Among the 219 procedures, the overall CE was significantly higher for Trima over MCS+ equipment (77 vs 56, P < 0.001). However, there was no difference in procedural outcomes like CE, Y/L, Y/H, CR with MCS+ or Trima equipment between groups. %BV processed had a negative correlation with hematocrit in MCS+ (r = - 0.305, P = 0.001) and no difference was observed with Trima equipment. Donor Hct influences C-SDP collection only in processed blood volume with MCS+ equipment. Trima had statistically better performance over MCS+ equipments in all procedural parameters during C-SDP procedures. The data will guide apheresis centre to choose equipments based on donor characteristics.

Evaluating the effect of donor anxiety levels and lifestyle characteristics on the activation of platelet concentrates

Background

Smoking, alcohol use, performing regular physical exercise, dietary habits, and anxiety level may cause platelet activation. We aimed to evaluate the anxiety levels, smoking status, alcohol intake, and sportive habits of donors, and determine their impact on the quality of apheresis-platelets.

Methods

State and Transient Anxiety Inventory (STAI) was used to determine the level of donors' anxiety. STAI has two subscales: S-anxiety scale (STAI-I) and T-anxiety scale (STAI-II), each comprising 20 questions rated on a 4-point Likert scale. Data on smoking, alcohol consumption, and performing regular physical exercise were obtained from a questionnaire filled out before donation. Flow cytometric analysis was used to quantify activated platelets.

Results

The STAI-I level of 86 participants was normal, while that of 12 was higher. No significant difference was found in the active platelet absolute count [1.8×10¹¹ (2.7) and 1.4×10¹¹ (1.3), respectively; P=0.665] between donors with normal STAI-I levels and those with higher STAI-I levels. Of 98 donors, 42 had normal STAI-II levels, while 56 had higher STAI-II levels. No significant difference was found in the active platelet absolute count [2.3×10¹¹ (3.1) and 1.5×10¹¹ (2.3), respectively; P=0.224] between donors with normal STAI-II levels and those with higher STAI-II levels. Platelet counts of individuals who perform regular physical exercise were significantly higher than those of individuals who did not perform regular physical exercise (6.3±1.4×10¹¹ vs. 5.5±1.4×10¹¹).

Conclusion

The quality of apheresis platelets is not affected by anxiety levels and lifestyle characteristics of blood donors. There is no need to organize apheresis blood donor pool considering with these subjects.

Comparison of Plateletpheresis on the Haemonetics and Trima Accel Cell Separators

The use of apheresis equipment to collect platelets has rapidly increased in recent years. We compared two apheresis instruments (Haemonetics MCS + and Trima Accel) with regard to platelet (PLT) yield and efficiency, and collection rate (CR) in a retrospective study. Overall 120 data obtained by Haemonetics and Trima systems (N = 60 for each) were randomly selected among 400 plateletpheresis procedures performed at the Apheresis Unit of Kayseri Education and Research Hospital between July 2016 and January 2017. The CR was significantly higher with the Haemonetics compared to the Trima (0.076 ± 0.016 vs. 0.065 ± 0.015 (PLT × 10¹¹ /min) respectively; P < 0.001). The PLT yield/unit was higher with the Haemonetics (4.4 ± 0.8 vs. 3.9 ± 0.8 × 10¹¹ , P = 0.001). Haemonetics and Trima Accel instruments collected platelets efficiently. We hope that these data will be a guide in selecting equipment for apheresis units.