Thromboelastography versus thromboelastometry for unfractionated heparin monitoring in adult patients on extracorporeal membrane oxygenation.

Background: Monitoring the anticoagulant effect of unfractionated heparin (UFH) in extracorporeal membrane oxygenation (ECMO) patients is complex but critically important to balance the risks of treatment related bleeding and circuit thrombosis. While guidelines recommend using more than one method to monitor UFH activity, the use of thromboelastometry (ROTEM) to monitor UFH in ECMO patients has not been investigated in detail.Methods: This is an observational, single-center retrospective study looking at adult ECMO patients on UFH that had ROTEM and thromboelastography (TEG) tests obtained concurrently. A total of 20 samples were obtained from nine patients during the study period, seven of which were on veno-arterial (VA) ECMO and two of which were on veno-venous (VV) ECMO.Results: Under institutional standard operating practice, when TEG and/or activated partial thromboplastin time (aPTT) were considered therapeutic, intrinsic thromboelastometry clotting time (INTEM CT) was only 1.2 times higher than the normal range. TEG based monitoring compared to aPTT based monitoring tended to result in lower anti-Xa levels and less intensive anticoagulation. For the total cohort, bleeding events, driven by the need for blood transfusions, were more common compared to ischemic events (77% vs 11%; p = 0.02).Conclusion: INTEM CT tended to be less sensitive to lower doses of UFH with a value of 1.2 times higher than the normal range when aPTT and/or TEG were considered therapeutic. Due to the relative insensitivity of ROTEM, our institution decided to continue to use TEG instead of ROTEM. Larger, multicenter trials may be helpful to validate these findings.

A survey of US hospitals on platelet inventory management, transfusion practice, and platelet availability.

BACKGROUND: A survey of US hospitals was conducted to increase our understanding of the current state of platelet (PLT) practice and supply. The survey captures information on transfusion practice and inventory management, including stock levels, outdate rates, ability to return or transfer PLTs, and low dose PLTs. Notably, the survey also elucidates PLT availability challenges and impact to patient care. STUDY DESIGN AND METHODS: A 27 question online survey was distributed directly to over 995 US hospitals and indirectly through blood centers to many more between September 27 and October 25, 2019. Descriptive statistics were used for respondent characteristics. Bivariate analysis was performed and correlation coefficients, chi square tests, and p values determined statistical significance of relationships between variables. RESULTS: Four hundred and eighty-one hospitals completed the survey of which 21.6%, 53.2%, and 25.2% were characterized as small, medium, and large hospitals, respectively. Some key observations from this survey include: (1) there is an opportunity for greater adherence to evidence-based guidelines; (2) higher outdate rates occur in hospitals stocking less than five PLTs and the ability to return or transfer PLTs lowers outdates; (3) use of low dose apheresis PLTs varies; and (4) decreased PLT availability is commonly reported, especially in hospitals with high usage, and can lead to delays in transfusions or surgeries. CONCLUSION: This survey represents a comprehensive national assessment of inventory management practices and PLT availability challenges in US hospitals. Findings from this survey can be used to guide further research, help shape future guidance for industry, and assist with policy decisions.

Plasma trial: Pilot randomized clinical trial to determine safety and efficacy of plasma transfusions.

BACKGROUND: Plasma is frequently administered to patients with prolonged INR prior to invasive procedures. However, there is limited evidence evaluating efficacy and safety. STUDY DESIGN AND METHODS: We performed a pilot trial in hospitalized patients with INR between 1.5 and 2.5 undergoing procedures conducted outside the operating room. We excluded patients undergoing procedures proximal to the central nervous system, platelet counts <40,000/µl, or congenital or acquired coagulation disorders unresponsive to plasma. We randomly allocated patients stratified by hospital and history of cirrhosis to receive plasma transfusion (10-15 cc/kg) or no transfusion. The primary outcome was change in hemoglobin concentration within 2 days of procedure. RESULTS: We enrolled 57 patients, mean age 56.0, 34 (59.6%) with cirrhosis, and mean INR 1.92 (SD = 0.27). In the intention to treat analysis, there were 10 of 27 (38.5%) participants in the plasma arm with a post procedure INR <1.5 and one of 30 (3.6%) in the no treatment arm (p < .01). The mean INR after receiving plasma transfusion was -0.24 (SD 0.26) lower than baseline. The change from pre-procedure hemoglobin level to lowest level within 2 days was -0.6 (SD = 1.0) in the plasma transfusion arm and -0.4 (SD = 0.6) in the no transfusion arm (p = .29). Adverse outcomes were uncommon. DISCUSSION: We found no differences in change in hemoglobin concentration in those treated with plasma compared to no treatment. The change in INR was small and corrected to less than 1.5 in minority of patients. Large trials are required to establish if plasma is safe and efficacious.

Effects of red-cell storage duration on patients undergoing cardiac surgery.

BACKGROUND: Some observational studies have reported that transfusion of red-cell units that have been stored for more than 2 to 3 weeks is associated with serious, even fatal, adverse events. Patients undergoing cardiac surgery may be especially vulnerable to the adverse effects of transfusion. METHODS: We conducted a randomized trial at multiple sites from 2010 to 2014. Participants 12 years of age or older who were undergoing complex cardiac surgery and were likely to undergo transfusion of red cells were randomly assigned to receive leukocyte-reduced red cells stored for 10 days or less (shorter-term storage group) or for 21 days or more (longer-term storage group) for all intraoperative and postoperative transfusions. The primary outcome was the change in Multiple Organ Dysfunction Score (MODS; range, 0 to 24, with higher scores indicating more severe organ dysfunction) from the preoperative score to the highest composite score through day 7 or the time of death or discharge. RESULTS: The median storage time of red-cell units provided to the 1098 participants who received red-cell transfusion was 7 days in the shorter-term storage group and 28 days in the longer-term storage group. The mean change in MODS was an increase of 8.5 and 8.7 points, respectively (95% confidence interval for the difference, -0.6 to 0.3; P=0.44). The 7-day mortality was 2.8% in the shorter-term storage group and 2.0% in the longer-term storage group (P=0.43); 28-day mortality was 4.4% and 5.3%, respectively (P=0.57). Adverse events did not differ significantly between groups except that hyperbilirubinemia was more common in the longer-term storage group. CONCLUSIONS: The duration of red-cell storage was not associated with significant differences in the change in MODS. We did not find that the transfusion of red cells stored for 10 days or less was superior to the transfusion of red cells stored for 21 days or more among patients 12 years of age or older who were undergoing complex cardiac surgery. (Funded by the National Heart, Lung, and Blood Institute; RECESS ClinicalTrials.gov number, NCT00991341.).

Proposed diagnostic criteria for the case definition of amniotic fluid embolism in research studies.

Amniotic fluid embolism is a leading cause of maternal mortality in developed countries. Our understanding of risk factors, diagnosis, treatment, and prognosis is hampered by a lack of uniform clinical case definition; neither histologic nor laboratory findings have been identified unique to this condition. Amniotic fluid embolism is often overdiagnosed in critically ill peripartum women, particularly when an element of coagulopathy is involved. Previously proposed case definitions for amniotic fluid embolism are nonspecific, and when viewed through the eyes of individuals with experience in critical care obstetrics, would include women with a number of medical conditions much more common than amniotic fluid embolism. We convened a working group under the auspices of a committee of the Society for Maternal-Fetal Medicine and the Amniotic Fluid Embolism Foundation whose task was to develop uniform diagnostic criteria for the research reporting of amniotic fluid embolism. These criteria rely on the presence of the classic triad of hemodynamic and respiratory compromise accompanied by strictly defined disseminated intravascular coagulopathy. It is anticipated that limiting research reports involving amniotic fluid embolism to women who meet these criteria will enhance the validity of published data and assist in the identification of risk factors, effective treatments, and possibly useful biomarkers for this condition. A registry has been established in conjunction with the Perinatal Research Branch of the Eunice Kennedy Shriver National Institute of Child Health and Human Development to collect both clinical information and laboratory specimens of women with suspected amniotic fluid embolism in the hopes of identifying unique biomarkers of this condition.

Exposure of early pediatric trainees to blood and marrow transplantation leads to higher recruitment to the field.

The National Marrow Donor Program (NMDP) projects the need for allogeneic unrelated blood and marrow transplantation (BMT) in the United States as 10,000 per year. Although the NMDP is preparing to facilitate that number by the year 2015, there are several barriers to meeting this goal, including the need to recruit more health care personnel, including BMT physicians. To learn how best to recruit BMT physicians, we examined why practicing BMT physicians chose to enter the field and why others did not. We conducted a Web-based survey among pediatric hematology/oncology (PHO) and BMT physician providers and trainees to identify the factors influencing their decision to choose or not choose a career in BMT. Out of 259 respondents (48% male, 74% of Caucasian origin), 94 self-identified as BMT physicians, 112 as PHO physicians, and 53 as PHO trainees. The PHO and BMT providers spent an average of 53% of their time in clinical activities. More than two-thirds of PHO providers reported providing BMT services at their institutions, most commonly for inpatient coverage (73%). The proportion of providers exposed to BMT early in training was significantly higher among BMT providers compared with PHO providers (51% versus 18% in medical school [P < .0001]; 70% versus 50% during residency [P < .005]). Exposure during fellowship (94%) did not differ between the 2 groups. The decision to pursue a career in BMT was made before fellowship (medical school or residency) by 50% of the respondents. A lower proportion of BMT providers than PHO providers reported current involvement in the education of medical students and residents (76% versus 98%; P < .0001). Of the 53 trainees who responded, 64% reported not contemplating a career in BMT. Of these, 68% identified inadequate exposure to BMT before PHO fellowship as the reason behind this decision. Only 26% reported receiving exposure to the BMT field while in medical school, and 43% reported exposure during residency. The 2 most common reasons cited for choosing a career as a BMT physician were the degree of intellectual and scientific challenge (89%) and the influence of role models/mentors in the field (67%). The results of this survey suggest that early exposure to BMT during medical school and residency is associated with increased interest in pursuing a career in BMT. BMT physicians and training program directors can foster interest in the field by promoting BMT-focused education and clinical inpatient and outpatient rotations during medical school and residency. This early exposure to BMT may aid recruitment of future transplantation providers.

Hematopoietic cell transplantation in 2020: summary of year 2 recommendations of the National Marrow Donor Program's System Capacity Initiative.

The National Marrow Donor Program, in partnership with the American Society for Blood and Marrow Transplantation, sponsored and organized a series of symposia to identify complex issues affecting the delivery of hematopoietic cell transplantation (HCT) and to collaboratively develop options for solutions. "Hematopoietic Cell Transplantation in 2020: A System Capacity Initiative" used a deliberative process model to engage professional organizations, experts, transplant centers, and stakeholders in a national collaborative effort. Year 2 efforts emphasized data analysis and identification of innovative ideas to increase HCT system efficiency, address future capacity requirements, and ensure adequate reimbursement for HCT programs to meet the projected need for HCT. This report highlights the deliberations and recommendations of Year 2 and the associated symposium held in September 2011.

Analysis of prolonged storage on coagulation Factor (F)V, FVII, and FVIII in thawed plasma: is it time to extend the expiration date beyond 5 days?

BACKGROUND: According to AABB standards, fresh-frozen plasma (FFP) should be thawed at 30 to 37°C and expire after 24 hours. An increase in the aggressive management of trauma patients with thawed plasma has heightened the risk of plasma waste. One way to reduce plasma waste is to extend its shelf life, given that the full range of therapeutic efficacy is maintained. We evaluated the effect of prolonged storage at 1 to 6°C on the activity of Factor (F)V, FVII, and FVIII in plasma thawed at 37 or 45°C. STUDY DESIGN AND METHODS: Group O plasma from healthy donors (n=20) was divided into 10 pairs and frozen and stored at not more than -18°C. One sample from each pair was thawed at 37 or 45°C, and all were stored at 1 to 6°C. Samples were analyzed for FV, FVII, and FVIII activity on Days 0, 5, 10, 15, and 20. RESULTS: Plasma thawing time was 17% less at 45°C than at 37°C. No differences were observed between thawing groups in coagulation activity of FV, FVII, and FVIII during the 20-day storage period (p>0.12). In both groups, the activity of FV and FVIII decreased over time but remained within a normal range at 10 days. CONCLUSION: Although levels of plasma clotting factors are reduced in storage, therapeutic levels of FV and FVIII are maintained in thawed plasma stored for up to 10 days at 1 to 6°C. Thawing of FFP at 45°C decreases thawing time but does not affect the activity of FV, FVII, and FVIII.

The National Marrow Donor Program's Symposium on Hematopoietic Cell Transplantation in 2020: a health care resource and infrastructure assessment.

Hematopoietic cell transplantation (HCT) is the only known curative therapy for many patients with life-threatening hematologic and oncologic diseases. It is estimated that the National Marrow Donor Program(®) (NMDP) will facilitate 10,000 transplants by 2015, double the current number. To better understand the existing personnel and center infrastructure for HCT in the country and to address system capacity challenges to the future growth of HCT, the NMDP convened a diverse group of stakeholders and thought leaders representing HCT physicians, physician assistants, nurse practitioners, nurses, pharmacists, other healthcare providers, HCT program directors, hospital administrators, payors, and professional organizations. Working groups were formed to identify: capacity issues because of shortages in human resources, structural constraints, and patient access barriers including diversity and healthcare disparity challenges; recommendations to address challenges; and stakeholders to engage. This report details the deliberations and recommendations of a national symposium, "Hematopoietic Cell Transplantation in 2020: A Health Care Resource and Infrastructure Assessment," held in September 2010.

Viscoelastic Haemostatic Assays in Cardiovascular Critical Care.

The initiation and management of anticoagulation is a fundamental practice for a wide variety of indications in cardiovascular critical care, including the management of patients with acute MI, stroke prevention in patients with AF or mechanical valves, as well as the prevention of device thrombosis and thromboembolic events with the use of mechanical circulatory support and ventricular assist devices. The frequent use of antiplatelet and anticoagulation therapy, in addition to the presence of concomitant conditions that may lead to a propensity to bleed, such as renal and liver dysfunction, present unique challenges. The use of viscoelastic haemostatic assays provides an additional tool allowing clinicians to strike a delicate balance of attaining adequate anticoagulation while minimising the risk of bleeding complications. In this review, the authors discuss the role that viscoelastic haemostatic assay plays in cardiac populations (including cardiac surgery, heart transplantation, extracorporeal membrane oxygenation, acute coronary syndrome and left ventricular assist devices), and identify areas in need of further study.

Plasmapheresis in Patients With Heparin-induced Thrombocytopenia Requiring Ventricular Assist Device.

Anticoagulation with unfractionated heparin is vital to reduce the risk of thromboembolic events during cardiopulmonary bypass and left ventricular assist device placement. However patients with heparin-induced thrombocytopenia are at risk of developing immune-mediated thrombotic events. We describe 2 patients with heparin-induced thrombocytopenia confirmed via serotonin release assay who were successfully treated with plasmapheresis exchange before left ventricular assist device placement.

Long-term Experience with Rapid Screening for Platelet Bacterial Contamination in a High-volume Transfusion Service.

Bacterial sepsis after platelet transfusion is a major cause of transfusion-transmitted infections in the US. The Food and Drug Administration (FDA) recommends performing quality control for platelet bacterial detection on days 4 and 5 before platelet transfusion. We assessed the feasibility of implementing the Pan Genera Detection (PGD) test, an FDA-approved immunoassay for platelet bacterial detection, for the primary and secondary bacterial screening of platelet units in a high-volume setting. Records were reviewed from January 2010 through December 2015. All apheresis platelets underwent primary screening by using culture methods. Additional screening with the PGD test was performed daily until February 2013, when PGD testing of apheresis platelets was performed at the start of storage day 5. In April 2015, PGD testing of apheresis platelet products was performed at the start of storage day 4. Post-storage pooled whole blood-derived platelets were screened by using the PGD test on the day of use. During the 6-year study period, 16,839 PGD tests were performed. If the PGD test was reactive, repeat PGD testing was performed. In cases of repeat reactivity, units were quarantined and cultured. Initially, 42 (0.25%) tests were reactive; 26/42 (61.91%) were repeatedly reactive and resulted in an overall PGD repeat reactivity rate of 0.15%. Only one sample grew coagulase-negative Staphylococcus No transfusion-transmitted infections were reported. The PGD bacterial detection assay was feasible and efficient in our high-volume transfusion service.

Evaluation of a heparin monitoring protocol for extracorporeal membrane oxygenation and review of the literature.

BACKGROUND: Bleeding complications are common with extracorporeal membrane oxygenation (ECMO). We investigated whether a heparin monitoring protocol using activated partial thromboplastin time (aPTT) and thromboelastography (TEG) affected clinical outcomes. METHODS: This retrospective chart review stratified cohorts by study interval: pre-protocol (January 2016-March 2017) or post-protocol (March 2017-December 2017). The protocol defined therapeutic anticoagulation as aPTT of 60-80 seconds and a TEG reaction (TEG-R) time of 2-4× baseline; pre-protocol management used aPTT alone. The primary endpoints were the rates of bleeding and thrombotic events (clinical/device thrombosis) as defined by Extracorporeal Life Support Organization (ELSO) guidelines. Secondary endpoints included time in therapeutic aPTT range, rate of physician compliance with the protocol, time to heparin initiation, intensive care unit length of stay, mortality, and antithrombin III (ATIII) supplementation. RESULTS: The pre-protocol (n=72) and post-protocol (n=51) groups (age 60±12 years; 80% on venoarterial ECMO; average ECMO duration of 6 days) showed no difference in baseline characteristics. Major bleeding events occurred in 69% of pre-protocol patients, versus 67% of post-protocol patients (P=0.85). The post-protocol group had fewer retroperitoneal bleeds (P=0.01) and had a non-significantly lower rate of pulmonary or central nervous system (CNS) bleeding (P=0.07). Thrombotic events occurred in 21% of the pre-protocol group, versus 28% of the post-protocol group (P=0.39). Mortality during ECMO support was significantly lower in the post-protocol group (56.9% vs. 33.3%, P=0.01). The thrombosis rate was higher in patients who received ATIII than in those who did not (48.2% vs. 15.9%, P<0.01). CONCLUSIONS: Major bleeding did not differ between the treatment groups. However, we observed significantly less mortality and retroperitoneal bleeding in the post-protocol group, suggesting an important gain from the intervention. Further study of the value of ATIII supplementation in ECMO patients is needed since we observed that a lower baseline ATIII level may indicate higher risk for thrombosis.

Plasma exchange before surgery for left ventricular assist device implantation.

Left ventricular assist device (LVAD) implantation in end-stage heart failure patients is frequently associated with hemorrhagic complications requiring reoperation. The preoperative coagulopathic profile includes prolonged prothrombin time (PT), partial thromboplastin time (PTT), and bleeding time; platelet dysfunction; decreased coagulation factor activity; and increased inflammatory markers. We compare outcomes in LVAD patients treated with preoperative plasma exchange with concurrent, nonrandomized control patients. We reviewed data from 68 consecutive elective patients who received LVADs at our institution. Thirty-five received LVADs after preoperative plasma exchange (replacement of one plasma volume of fresh frozen plasma), and 33 received LVADs without plasma exchange. Groups were comparable in age, sex, body weight, New York Heart Association class, intra-aortic balloon pump insertion, cardiac index, pulmonary capillary wedge pressure, creatinine, total bilirubin, hemoglobin levels, PT, international normalized ratio, PTT, and platelet count. Early mortality was lower in the plasma exchange group (0% [0/35] vs. 18% [6/33], P = 0.026), and postoperative chest tube drainage decreased by 33% (P = not significant). Blood transfusion requirements were similar. Perioperative mortality decreased in patients treated with plasma exchange before LVAD implantation.

Intraoperative anticoagulation management during cardiac transplantation for a patient with heparin-induced thrombocytopenia and a left ventricular assist device.

Heparin-induced thrombocytopenia is an immunologically mediated syndrome that is associated with potentially life-threatening arterial and venous thrombosis. Re-exposing patients who have heparin-induced thrombocytopenia to heparin during cardiopulmonary bypass may be hazardous. We describe the re-exposure to unfractionated heparin of a patient with a left ventricular assist device and evidence of heparin-induced thrombocytopenia who needed cardiac transplantation, which was accomplished without complications.