Abstract

BACKGROUND AND OBJECTIVES Platelets for transfusion have a shelf-life of 7 days, limiting availability and leading to wastage. Cryopreservation at -80°C extends shelf-life to at least 1 year, but safety and effectiveness are uncertain. MATERIALS AND METHODS This single centre blinded pilot trial enrolled adult cardiac surgery patients who were at high risk of platelet transfusion. If treating clinicians determined platelet transfusion was required, up to three units of either cryopreserved or liquid-stored platelets intraoperatively or during intensive care unit admission were administered. The primary outcome was protocol safety and feasibility. RESULTS Over 13 months, 89 patients were randomized, 23 (25.8%) of whom received a platelet transfusion. There were no differences in median blood loss up to 48 h between study groups, or in the quantities of study platelets or other blood components transfused. The median platelet concentration on the day after surgery was lower in the cryopreserved platelet group (122 × 10(3) /μl vs. 157 × 10(3) /μl, median difference 39.5 ×10(3) /μl, p = 0.03). There were no differences in any of the recorded safety outcomes, and no adverse events were reported on any patient. Multivariable adjustment for imbalances in baseline patient characteristics did not find study group to be a predictor of 24-h blood loss, red cell transfusion or a composite bleeding outcome. CONCLUSION This pilot randomized controlled trial demonstrated the feasibility of the protocol and adds to accumulating data supporting the safety of this intervention. Given the clear advantage of prolonged shelf-life, particularly for regional hospitals in New Zealand, a definitive non-inferiority phase III trial is warranted.

Abstract

BACKGROUND Evidence comparing fibrin sealants (FSs) in surgery are limited. This study evaluated the efficacy and safety of FSs, and manual compression in peripheral vascular surgery. METHODS A systematic review of randomized trials was conducted in Medline, Embase, and Cochrane databases within the last 15 years. Data were available to conduct a network meta-analysis (NMA) in peripheral vascular surgery. Fibrin sealant treatment arms were further broken-down and assessed by clotting time (i.e., 2-min [2C] or 1-min [1C]). The primary efficacy outcome was the proportion of patients achieving hemostasis by 4 min (T4). Treatment-related serious and non-serious adverse events (AEs) were qualitatively assessed. RESULTS Five studies (n = 693), were included in the NMA. Results predicted VISTASEAL 2C, followed by EVICEL 1C, had the highest probability of achieving T4. Compared with manual compression, significant improvements in T4 were found with VISTASEAL 2C (relative risk [RR] = 2.67, 95% CrI: 2.13-3.34), EVICEL 1C (RR = 2.58, 95% CrI: 2.04-3.23), VISTASEAL 1C (RR = 2.00, 95% CrI: 1.45-2.65), and TISSEEL 2C (RR = 1.99, 95% CrI: 1.48-2.60). TISSEEL 1C was not significantly different than manual compression (RR = 1.40, 95% CrI: 0.70-2.33). Among FSs, VISTASEAL 2C was associated with a significant improvements in T4 compared with VISTASEAL 1C (RR = 1.33, 95% CrI: 1.02-1.82), TISSEEL 2C (RR = 1.34, 95% CrI: 1.05-1.77), and TISSEEL 1C (RR = 1.90, 95% CrI: 1.18-3.74). Treatment-related serious and non-serious AE rates were typically lower than 2%. CONCLUSIONS In peripheral vascular surgeries, VISTASEAL 2C and EVICEL 1C were shown to have the highest probabilities for achieving rapid hemostasis among the treatments compared. Future studies should expand networks across surgery types as data become available.

Abstract

BACKGROUND To explore the effects of isovolumic hemodilution and platelet-rich plasma separation on platelet activation state and function, complications, and inflammation in patients undergoing cardiac surgery. METHODS A total of 80 patients who needed cardiac surgery under extracorporeal circulation from February 2018 to December 2019 in our hospital were selected as research subjects and divided into observation group (n = 40) and control group (n = 40) according to the random number table method. The patients in the observation group underwent platelet-rich plasma separation, while those in control group received acute isovolumic hemodilution. Then the platelet activation state and functional indexes, hemorheological indexes, and the coagulation functional indexes were compared between the two groups of patients before operation. Next, the changes in the levels of hemoglobin and high-sensitivity C-reactive protein (hs-CRP), an inflammatory factor, during blood protection (before and at 6 hours and 12 hours after intervention) were analyzed. Moreover, the dosage of blood products during operation was compared between the two groups, and postoperative complications and recovery in the two groups were statistically assessed. RESULTS Before operation, the platelet adherence rate and aggregation rate in the observation group were significantly higher than those in control group (p < 0.05), while R and K values in thromboelastograms in the former were notably smaller than those in the latter (p < 0.05). Meanwhile, the whole blood low-shear viscosity, whole blood high-shear viscosity, and plasma viscosity in observation group were remarkably lower than those in control group (p < 0.05). In addition, the observation group exhibited shorter prothrombin time (PT), thrombin time (TT), and activated partial thromboplastin time (APTT) (p < 0.05) and a higher fibrinogen (Fib) level (p < 0.05) than the control group. At 6 hours and 12 hours after intervention and before operation, the hemoglobin level in observation group was markedly higher than that in control group (p < 0.05). In addition, the dosages of red blood cells, fresh frozen plasma, and platelets among blood products during operation in the observation group were evidently lower than those in the control group (p < 0.05), and the number of cases of hemorrhage, pulmonary infection, coagulation dysfunction, and paraplegia after operation in the former was distinctly smaller than that in the latter (p < 0.05). Furthermore, the observation group had an obviously smaller postoperative 24 hours drainage volume (p < 0.05) as well as shorter postoperative mechanical ventilation time and ICU treatment time than control group (p < 0.05). CONCLUSIONS For patients undergoing cardiac surgery under extracorporeal circulation, platelet-rich plasma separation and reinfusion technology can effectively ensure platelet activation state and function, reduce blood viscosity, ensure stable coagulation function, elevate hemoglobin level and decrease inflammatory reaction, and perioperative allogeneic blood infusion, with fewer adverse reactions in treatment, thus efficaciously facilitating the post-operative recovery of patients.

Abstract

Objective: To examine the blood protective effect of autologous platelet-rich plasma separation for cardiac valve replacement under cardiopulmonary bypass. Methods: Sixty patients who underwent cardiac valve replacement under cardiopulmonary bypass from August 2018 to May 2019 in Shanghai Chest Hospital, Shanghai Jiao Tong University were randomly divided into control and treatment groups(each 30 cases). There were 33 males and 27 females, aged (52.0±8.4) years (range: 35 to 65 years). Autologous platelet separation was performed in the treatment group after anaesthesia administration and was completed before systemic heparinisation. Platelet separation was not performed in the control group. The thromboelastogram, blood routine, blood coagulation, perioperative fluid infusion, allogeneic blood transfusion, postoperative pleural fluid volume and postoperative fibrinogen were recorded before the operation, and 1 hour and 24 hours post operation. The two groups' data was compared by t test, Kruskal-Wallis test, Mann-Whitney U test or χ(2) test. Repeated measurement analysis of variance was used to compare platelet and coagulation indexes at different times. Results: The perioperative red blood cell transfusion of 0, 1~2, 3~4,>4 units with 6, 11, 1, 12 cases in treatment group and 14, 8, 6, 2 cases in control group (Z=-2.516, P=0.012). The postoperative fibrinogen of 0, 1, 2 units with 19, 2, 9 cases in treat group and 26, 2, 2 cases in control group (Z=-2.190, P=0.029). There was no significant difference in the cost of blood transfusion between the two groups during admission ((1 732±1 275) yuan vs. (1 176±941) yuan; t=-1.570, P=0.125). Conclusion: The use of autologous platelet-rich plasma separation can reduce the amount of allogeneic blood transfusion during valvular surgery under cardiopulmonary bypass.

Abstract

BACKGROUND Blood transfusion is a well-established independent risk factor for mortality in patients undergoing cardiac surgery but the impact of platelet transfusion is less clear. We performed a systematic review and meta-analysis of observational studies comparing outcomes of patients who received platelet transfusion following cardiac surgery. METHODS We searched MEDLINE and EMBASE databases to January 2019 for studies comparing peri-operative outcomes in patients undergoing cardiac surgery with and without platelet transfusion. RESULTS There were 9 observational studies reporting on 101,511 patients: 12% with and 88% without platelet transfusion. In unmatched/unadjusted studies, patients who received platelet transfusion were older with greater incidence of renal, peripheral and cerebrovascular disease, myocardial infarction, left ventricular dysfunction, and anemia. They were more likely to have non-elective, combined surgery; pre-operative hemodynamic instability and endocarditis; and more likely to be on clopidogrel preoperatively. Perioperative complications were significantly increased without adjusting for these baseline differences. After pooling only matched/adjusted data, differences were not found in patients who did vs did not receive platelets for operative mortality (risk ratio [RR] 1.26, 95%CI:0.69-2.32, p=0.46, 5 studies), stroke (RR 0.94, 95%CI:0.62-1.45, p=0.79, 5 studies), myocardial infarction (RR1.29, 95%CI:0.95-1.77, p=0.11, 3 studies), reoperation for bleeding (RR1.20, 95%CI:0.46-3.18, p=0.71, 3 studies), infection (RR1.02, 95%CI:0.86-1.20, p=0.85, 6 studies), and peri-operative dialysis (RR0.91, 95%CI:0.63-1.32, p=0.62, 3 studies). CONCLUSIONS After accounting for baseline differences, platelet transfusion was not linked with perioperative complications in cardiac surgery patients. Given the small number of observational studies, these findings should be considered hypothesis generating.

Abstract

BACKGROUND This pilot trial focused on feasibility and safety to provide preliminary data to evaluate the hemostatic potential of cold-stored platelets (2° to 6°C) compared with standard room temperature-stored platelets (20° to 24°C) in adult patients undergoing complex cardiothoracic surgery. This study aimed to assess feasibility and to provide information for future pivotal trials. METHODS A single center two-stage exploratory pilot study was performed on adult patients undergoing elective or semiurgent complex cardiothoracic surgery. In stage I, a two-armed randomized trial, platelets stored up to 7 days in the cold were compared with those stored at room temperature. In the subsequent single-arm stage II, cold storage time was extended to 8 to 14 days. The primary outcome was clinical effect measured by chest drain output. Secondary outcomes were platelet function measured by multiple electrode impedance aggregometry, total blood usage, immediate and long-term (28 days) adverse events, length of stay in intensive care, and mortality. RESULTS In stage I, the median chest drain output was 720 ml (quartiles 485 to 1,170, n = 25) in patients transfused with room temperature-stored platelets and 645 ml (quartiles 460 to 800, n = 25) in patients transfused with cold-stored platelets. No significant difference was observed. The difference in medians between the room temperature- and cold-stored up to 7 days arm was 75 ml (95% CI, -220, 425). In stage II, the median chest drain output was 690 ml (500 to 1,880, n = 15). The difference in medians between the room temperature arm and the nonconcurrent cold-stored 8 to 14 days arm was 30 ml (95% CI, -1,040, 355). Platelet aggregation in vitro increased after transfusion in both the room temperature- and cold-stored platelet study arms. Total blood usage, number of adverse events, length of stay in intensive care, and mortality were comparable among patients receiving cold-stored and room temperature-stored platelets. CONCLUSIONS This pilot trial supports the feasibility of platelets stored cold for up to 14 days and provides critical guidance for future pivotal trials in high-risk cardiothoracic bleeding patients.

Abstract

BACKGROUND Cryopreservation extends platelet (PLT) shelf life from 5 to 7 days to 2 to 4 years. However, only 73 patients have been transfused cryopreserved PLTs in published randomized controlled trials (RCTs), making safety data insufficient for regulatory approval. STUDY DESIGN AND METHODS The Cryopreserved vs. Liquid Platelet (CLIP) study was a double-blind, pilot, multicenter RCT involving high-risk cardiothoracic surgical patients in four Australian hospitals. The objective was to test, as the primary outcome, the feasibility and safety of the protocol. Patients were allocated to study group by permuted block randomization, with patients and clinicians blinded by use of an opaque shroud placed over each study PLT unit. Up to 3 units of cryopreserved or liquid-stored PLTs were administered per patient. No other aspect of patient care was affected. Adverse events were actively sought. RESULTS A total of 121 patients were randomized, of whom 23 received cryopreserved PLTs and 18 received liquid-stored PLTs. There were no differences in blood loss (median, 715 mL vs. 805 mL at 24 hr; difference between groups 90 mL [95% CI, -343.8 to 163.8 mL], p = 0.41), but the Bleeding Academic Research Consortium criterion for significant postoperative hemorrhage in cardiac surgery composite bleeding endpoint occurred in nearly twice as many patients in the liquid-stored group (55.6% vs. 30.4%, p = 0.10). Red blood cell transfusion requirements were a median of 3 units in the cryopreserved group versus 4 units with liquid-stored PLTs (difference between groups, 1 unit [95% CI, -3.1 to 1.1 units]; p = 0.23). Patients in the cryopreserved group were more likely to be transfused fresh-frozen plasma (78.3% vs. 27.8%, p = 0.002) and received more study PLT units (median, 2 units vs. 1 unit; difference between groups, 1 unit [95% CI, -0.03 to 2.0 units]; p = 0.012). There were no between-group differences in potential harms including deep venous thrombosis, myocardial infarction, respiratory function, infection, and renal function. No patient had died at 28 days, and postoperative length of stay was similar in each group. CONCLUSION In this pilot RCT, compared to liquid-stored PLTs, cryopreserved PLTs were associated with no evidence of harm. A definitive study testing safety and hemostatic effectiveness is warranted.

Abstract

Background: To investigate whether lower limb vascular intervention or autologous platelet-rich gel (APG) treatment would benefit diabetic lower extremity arterial disease (LEAD) patients with foot ulcers. Methods: A total of 82 diabetic LEAD patients with foot ulcers were recruited and divided into three groups: group A (30 patients received basal treatment), group B (21 patients received basal and APG treatment), and group C (31 patients received basal and lower limb vascular intervention treatment). All patients underwent routine follow-up visits for 6 months. The baseline characteristics and parameters were examined. After treatment, changes in all parameters from baseline were recorded. The differences between groups and the relationship among each parameter were determined. Results: There were no differences in the ankle brachial index (ABI) or major amputation between groups A and B (P>0.05). Compared with groups A and B, the ABI and major amputation rate of group C were improved (P<0.05). There were no significant differences in transcutaneous oxygen partial pressure (TcPO2), the heal rate or minor amputation between groups A and C (P>0.05). Compared with groups A and C, TcPO2, the heal rate and minor amputation of group B were improved (P<0.05). The logistic regression analysis indicated that major amputation was mainly associated with the ABI, and minor amputation was mainly associated with TcPO2. Lower limb vascular intervention improves the ABI and reduces major amputation, and APG improves TcPO2 and reduces minor amputation. Conclusions: In diabetic LEAD patients with foot ulcers, major amputation was mainly associated with the ABI, while minor amputation was mainly associated with TcPO2. Interventional surgery (angioplasty) mainly improves the ABI, reduces the incidence of major amputation and improves the macrovasculature, and APG mainly improves local TcPO2, reduces the incidence of minor amputation and improves the microcirculation.

Abstract

BACKGROUND In patients undergoing open surgery for a ruptured abdominal aortic aneurysm (rAAA), survivors demonstrate a high platelet count, and proactive administration of platelets (and fresh frozen plasma) appears to influence mortality. OBJECTIVES This trial investigated the effect of platelets administered before transport to surgery. METHODS In a prospective study design, patients were randomised to receive platelets (intervention; n = 61) or no platelets (control; n = 61) before transport to vascular surgery from 11 local hospitals. The study was terminated when one of the vascular surgical centres implemented endovascular repair for rAAA patients. RESULTS Thirty days after surgery, mortality was 36% for patients with intervention vs 31% for controls (P = 0.32). Post-operative thrombotic events (14 vs 15; P = 0.69), renal failure (11 vs 10; P = 0.15) and pulmonary insufficiency (34 vs 39; P = 0.15) were similar in the two groups of patients. No adverse reactions to platelet administration were observed. In addition, length of stay in the intensive care unit was unaffected by intervention. CONCLUSIONS For patients planned for open repair of a rAAA, we observed no significant effect of early administration of platelets with regard to post-operative complications and stay in the ICU or in hospital and also no significant effect on mortality.

Abstract

To evaluate the parameters of the thrombin generation test (TGT) in coronary artery disease (CAD) patients on prolonged aspirin therapy during on-pump coronary artery bypass grafting (CABG) after donor platelet concentrate transfusion. A total of 148 patients with CAD on prolonged aspirin therapy (75-100 mg/day) who have undergone elective on-pump CABG were consecutively included in the study. Patients were divided randomly into two groups. Group 1 (n = 76) received donor platelet transfusions after cardiopulmonary bypass, whereas Group 2 (n = 72) did not. TGT parameters were measured using an analyzer at pre-, intra-, and early postoperative periods. Activation of the endogenous thrombin potential was observed in patients on prolonged aspirin therapy in the pre- and intraoperative periods, as confirmed by high peak thrombin and increased velocity index. The activation time of the prothrombinase complex and thrombin generation time were greater than the control group. The blood hemostatic potential in patients who did not receive transfusions in the early postoperative period decreased up to the level of the control group in the extended time parameters. Hemostatic potential in plasma in patients on aspirin was preserved. Given the laboratory test results and clinical data, platelet concentrate transfusion is unnecessary for prevention.