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.

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.

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.

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.

Use of an Intravascular Warming Catheter during Off-Pump Coronary Artery Bypass Surgery in a Patient with Severe Cold Hemagglutinin Disease

Cold hemagglutinin disease with broad thermal amplitude and high titers presents challenges in treating cardiac-surgery patients. Careful planning is needed to prevent the activation of cold agglutinins and the agglutination of red blood cells as the patient's temperature drops during surgery. We describe our approach to mitigating cold agglutinin formation in a 77-year-old man with severe cold hemagglutinin disease who underwent off-pump coronary artery bypass surgery without the use of preoperative plasmapheresis. This experience shows that the use of an intravascular warming catheter can maintain normothermia and prevent the activation and subsequent formation of cold agglutinins. To our knowledge, this is the first reported use of this technique in a patient with cold hemagglutinin disease. The chief feature in this approach is the use of optimal thermal maintenance-rather than the more usual decrease in cold-agglutinin content by means of therapeutic plasma exchange.

Significance of anaemia in patients with advanced heart failure receiving long-term mechanical circulatory support

AIMS

The aim of this study was to analyse the prognostic impact of anaemia in patients receiving long-term left ventricular assist device (LVAD) support.

METHODS AND RESULTS

We reviewed the data of 65 consecutive patients who underwent LVAD support for at least 6 months. Anaemia was defined as haemoglobin levels <12.0 g/dL. Follow-up was performed 15 months after implantation. Anaemia was present in 30/65 patients (46%) after 6 months of LVAD support. Anaemic patients had higher levels of pre-implant creatinine (1.8 +/- 0.8 vs. 1.4 +/- 0.5 mg/dL; P = 0.04). The presence of anaemia after 6 months correlated with higher levels of creatinine and blood urea nitrogen and lower levels of albumin. Multivariate Cox proportional hazards regression analysis revealed that levels of haemoglobin <12 g/dL [risk ratio (RR), 8.94; 95% confidence interval (CI), 1.09-73.01; P = 0.04], creatinine >1.4 mg/dL (RR, 5.39; 95% CI, 1.78-16.30; P = 0.003), and albumin <1.5 g/L (RR, 3.23; 95% CI, 1.10-9.51; P = 0.03) were associated with all-cause mortality at 15 months. Long-term survival evaluated by Kaplan-Meier analysis was two times higher in non-anaemic patients after 6 months of LVAD support than in anaemic patients (P = 0.01).

CONCLUSION

Anaemia is related to adverse outcomes in patients receiving prolonged LVAD support.

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.

Impact of platelet testing on presurgical screening and implications for cardiac and noncardiac surgical procedures

Bleeding is a common complication of cardiac surgery, accounting for a significant portion of the total transfusions performed in the United States. This may be due in part to surgical factors and to the fibrinolysis and platelet activation induced by cardiopulmonary bypass. The increasing frequency with which antiplatelet medications are used to prevent thrombosis in cardiac surgical patients with cardiovascular disease also elevates the risk for postoperative bleeding. The resulting coagulopathy and need for transfusions may increase morbidity and mortality risk in cardiac surgical patients, depending on the specific antiplatelet agent used, as well as on patient factors. Empiric platelet transfusion, the frequency of which varies greatly among institutions, does not reliably prevent these complications and may even increase the risk for adverse outcomes. Platelet function testing, particularly with newer testing systems, may be a valuable tool for making decisions about stopping antiplatelet drug administration, surgical timing with respect to bleeding risk, and platelet transfusion in cardiac surgical patients.

The effect of administering erythropoiesis-stimulating proteins in patients with chronic heart failure: results from a retrospective study

Anemia is prevalent in patients with chronic heart failure and is associated with worse symptoms and poor prognosis. The authors reviewed the charts of all patients (N=467) treated at Texas Heart Institute from January 2000 to October 2003, during which time a clinical protocol offered treatment with erythropoiesis-stimulating proteins. Post-treatment, the authors observed a significant increase in mean +/- SD hemoglobin, from 9.9+/-1.1 g/dL to 11.7+/-1.5 g/dL (P<.0001), improvement of renal function (a decrease in mean levels of creatinine and blood urea nitrogen), and fewer hospital admissions (1.0+/-1.4 vs 1.8+/-1.6; P=.0003) without an increase in adverse clinical events, compared with pretreatment and compared with an untreated control group. These results suggest a potential benefit of anemia treatment with recombinant erythropoiesis-stimulating proteins in patients with chronic heart failure.

Fatal pulmonary microthrombi during surgical therapy for end-stage heart failure: Possible association with antifibrinolytic therapy

BACKGROUND

Maintaining hemostasis in patients with end-stage heart failure undergoing cardiac surgery is always challenging. These patients have chronic hepatic insufficiency, resulting in derangement of coagulation. In addition, they are commonly receiving both systemic anticoagulation (warfarin or heparin) and antiplatelet therapy. The introduction of antifibrinolytics has had a significant effect on postoperative coagulopathy. We report fatal pulmonary microthrombi in patients receiving antifibrinolytics who developed suprasystemic pulmonary artery pressures and right heart failure that was impossible to overcome despite insertion of a right ventricular assist device.

METHODS

We reviewed the surgical procedure and autopsy reports to identify patients with high pulmonary artery pressures caused by pulmonary microthrombi after a cardiac surgical procedure for end-stage heart failure. Patient demographics and preoperative, intraoperative, and postoperative variables were collected from a retrospective review of the patients' medical records.

RESULTS

We identified 9 patients (7 men and 2 women; mean age, 45 +/- 16 years) who died of pulmonary microthrombi after cardiac surgery between January 1997 and January 2004. Surgical procedures included 5 left ventricular assist device implantations, 2 heart transplantations, and 2 left ventricular reconstructions with mitral valve repair or replacement. Eight patients received aprotinin, and 1 patient received epsilon-aminocaproic acid immediately before and during cardiopulmonary bypass. All patients had severe suprasystemic pulmonary artery pressures after protamine administration for heparin reversal, a complication that proved fatal in all cases. Intraoperative wedge biopsy of the lungs revealed multiple microthrombi within capillaries and in the small- and medium-sized pulmonary arterioles.

CONCLUSION

We report 9 cases for which fatal pulmonary microthrombi might be associated with the use of prophylactic antifibrinolytic therapy. Mortally ill patients with multiorgan failure who are receiving systemic anticoagulation and undergoing surgical procedures require careful perioperative monitoring to identify potential hazards. Anticoagulation and antifibrinolytic therapy protocols may require adjustment in such patients.

Pulmonary microthrombi during left ventricular assist device implantation

Critically ill heart failure patients undergoing left ventricular assist device implantation have alterations in their coagulation profiles; as a result, hemorrhagic complications during the postoperative period are the most common and serious problems during device support of these patients. The use of aprotinin therapy is generally accepted for reducing bleeding after coronary artery bypass grafting procedures, heart transplantation, and insertion of a left ventricular assist device. We describe the case of a patient who had a suprasystemic increase in pulmonary artery pressure, caused by thromboembolic occlusion of the pulmonary arterioles after urgent implantation of a left ventricular assist device. The complications developed after the patient was weaned from cardiopulmonary bypass and heparinization was reversed with protamine. Although the thrombosis was successfully reversed with intraoperative administration of tissue plasminogen activator directly to the pulmonary artery, the patient died of massive hemorrhage 6 hours later. To our knowledge, the direct application of tissue plasminogen activator into the pulmonary artery in such a catastrophic situation has not been used elsewhere.

A successful anticoagulation protocol for the first HeartMate II implantation in the United States

Bleeding and thrombus formation are common problems with life-threatening implications in patients receiving a left ventricular assist device. We describe the anticoagulation protocol for the 1st patient in the United States to undergo successful implantation of the HeartMate II left ventricular assist system.

Clopidogrel and bleeding in patients undergoing elective coronary artery bypass grafting

OBJECTIVE

In an effort to minimize transfusions in patients undergoing elective coronary artery bypass grafting operations after recent clopidogrel exposure, we studied laboratory tests predictive of platelet dysfunction and used a strict algorithm-driven treatment of bleeding.

METHODS

Forty-five patients receiving clopidogrel within 6 days of the operation and 45 control subjects were studied. Prothrombin time, activated partial thromboplastin time, platelet count, and platelet function test results were measured before heparinization, after protamine administration, and then every 2 hours. No transfusions were administered unless a patient met both laboratory and clinical criteria.

RESULTS

Algorithm-driven treatment of bleeding significantly reduced the mean units of all blood components transfused by about one third, as shown by comparison with current control and historical data. Compared with current control subjects, clopidogrel recipients required significantly more transfusions of platelets (9.0 +/- 1.7 vs 1.2 +/- 0.5 U; P <.0001) and packed red blood cells (4.3 +/- 0.6 vs 2.3 +/- 0.5 U; P =.01) and required longer periods of controlled ventilation (12.4 +/- 1.3 vs 8.6 +/- 0.8 hours; P =.02). Preoperative platelet dysfunction before heparin administration for cardiopulmonary bypass, as measured by using adenosine diphosphate aggregometry (response <40%), predicted all but 1 case of severe coagulopathy requiring multiple transfusions (16.6 +/- 2.8 U of platelets and 5.8 +/- 1.0 U of packed red blood cells).

CONCLUSIONS

A strict transfusion algorithm can reduce the transfusion requirement for all blood components. Preheparin testing of platelet function with adenosine diphosphate aggregometry can identify patients at highest risk for perioperative bleeding and transfusions and might further reduce the perioperative transfusion requirement.

Management of patients refractory to platelet transfusion

OBJECTIVE

To present a current assessment and practical approach to the diagnosis and management of patients who are refractory to platelet transfusions.

DESIGN

A task force was convened by the College of American Pathologists under the auspices of the Transfusion Medicine Resource Committee for the purposes of outlining current concepts in the definition and diagnosis of this difficult clinical management problem and selection of the optimal platelet component for these patients.

RESULTS

This article represents a contemporary approach to the diagnosis and management of patients who are refractory to platelet transfusions. This document is based on a current literature review and dialog among members of the task force convened to address the subject.

CONCLUSIONS

It is hoped that this document will represent a resource and practical approach to the issue of diagnosis and management of patients who are refractory to platelet transfusions.

Lowering the hemoglobin threshold for transfusion in coronary artery bypass procedures: effect on patient outcome

BACKGROUND

There is controversy regarding the application of transfusion triggers in cardiac surgery. The goal of this study was to determine if lowering the hemoglobin threshold for red cell (RBC) transfusion to 8 g per dL after coronary artery bypass graft surgery would reduce blood use without adversely affecting patient outcome.

STUDY DESIGN AND METHODS

Consecutive patients (n = 428) undergoing elective primary coronary artery bypass graft surgery were randomly assigned to two groups: study patients (n = 212) received RBC transfusions in the postoperative period if the Hb level was < 8 g per dL or if predetermined clinical conditions required RBC support, and control patients (n = 216) were treated according to individual physician's orders (hemoglobin levels < 9 g/dL as the institutional guideline). Multiple demographic, procedure-related, transfusion, laboratory, and outcome data were analyzed. Questionnaires were administered for patient self-assessment of fatigue and anemia.

RESULTS

Preoperative and operative clinical characteristics, as well as the intraoperative transfusion rate, were similar for both groups. There was a significant difference between the postoperative RBC transfusion rates in study (0.9 +/- 1.5 RBC units) and control (1.4 +/- 1.8 RBC units) groups (p = 0.005). There was no difference in clinical outcome, including morbidity and mortality rates, in the two groups; group scores for self-assessment of fatigue and anemia were also similar.

CONCLUSIONS

A lower Hb threshold of 8 g per dL does not adversely affect patient outcome. Moreover, RBC resources can be saved without increased risk to the patient.

Blood use in patients undergoing repeat coronary artery bypass graft procedures: multivariate analysis

BACKGROUND

The prevailing clinical opinion is that patients undergoing repeat coronary artery bypass graft (CABG) operation require more blood transfusions than do patients undergoing primary CABG operation. To determine the extent of this increased demand and the variables responsible for it, the cases of 196 patients who had undergone primary procedures and 65 patients who had had repeat procedures at the same institution were reviewed.

STUDY DESIGN AND METHODS

To analyze the differences in transfusion requirements for these two groups, the following data were obtained: number of transfusions given between the time of surgery and the time of hospital discharge; preoperative hemoglobin (Hb), hematocrit (Hct), prothrombin time, and platelet count; Hb and Hct at hospital discharge; time the patient was on cardiopulmonary bypass; number and type of grafts; estimates of intraoperative blood loss; and chest-tube blood shed during the first 48 hours after surgery.

RESULTS

The groups were comparable with respect to age, body weight, preoperative Hb and Hct, number of grafts, and aspirin exposure. Patients in the repeat group had 35-percent greater blood loss and required 75-percent more blood components than did the patients undergoing primary procedures. The mean number of blood components transfused per patient was as follows: red cells, 3.8 +/- 0.5 units in repeat patients and 2.2 +/- 0.2 units in primary patients (p = 0.002); platelets, 2.9 +/- 0.9 vs. 1.1 +/- 0.2 (p = 0.043); fresh-frozen plasma, 1.6 +/- 0.4 vs. 0.8 +/- 0.1 (p = 0.044). Analysis of variables by regression method for repeat patients showed a predictive effect of blood loss (p < 0.0001), prolonged time on cardiopulmonary bypass (p < 0.0001), preoperative Hb (p = 0.0003), and aspirin exposure (p = 0.0094) on red cell transfusion rate in repeat patients (R-square = 0.7778, Prob > f = 0.0001).

CONCLUSION

Repeat CABG patients have higher transfusion rates. These findings may be attributed to the increased microvascular bleeding, prolonged time on cardiopulmonary bypass, lower preoperative Hb, and the use of preoperative antiplatelet medications.

The hematologic effects of cardiopulmonary bypass and the use of hemotherapy in coronary artery bypass grafting

Blood component therapy has always been important in coronary artery bypass grafting, and, initially, all patients undergoing bypass operations were given transfusions. The advent of hemodilution marked the beginning of blood conservation efforts that have reduced the transfusion requirements for these patients. We review the current state of cardiopulmonary bypass, blood loss, and blood use in coronary artery bypass grafting, including coagulation disturbances, preoperative autologous blood collection, blood conservation techniques, transfusion thresholds, blood component therapy, and blood use data.

Hypothermia and blood coagulation: dissociation between enzyme activity and clotting factor levels

Previous studies of hypothermia and blood coagulation have focused on alterations in the levels of blood clotting elements using coagulation tests performed under normothermic conditions. However, because of the enzymatic nature of activated clotting factors, hypothermia should also be expected to affect clotting factor activities. Multiple determinations of activated partial thromboplastin times (APTT), prothrombin times (PT), and thrombin times (TT) were performed on commercially available normal human plasma at assay temperatures similar to those encountered clinically (25-37 degrees C). Both the APTT and the PT were significantly prolonged at temperatures below 35 degrees C (P less than 0.05). Clotting time correlated significantly with assay temperature in a negative exponential fashion for all three tests (r = -0.97 for APTT, -0.93 for PT, -0.71 for TT, P less than 0.001 for all regressions). Clotting time prolongation appears proportional to the number of enzymatic steps involved. These data indicate that the coagulopathy observed during hypothermia is, in part, independent of clotting factor levels.

Coexistence of myelodysplastic syndrome and untreated chronic lymphocytic leukemia with development of acute myeloid leukemia immediately after treatment of chronic lymphocytic leukemia

A 72-year-old man originally seen for anemia and thrombocytopenia was determined to have chronic lymphocytic leukemia (CLL). Bone marrow examination at the time of CLL diagnosis revealed a small but significant population of atypical blasts. Cytogenetic analysis of the bone marrow aspirate disclosed chromosomal abnormalities (-7, +8) suggestive of a myelodysplastic syndrome. Shortly after treatment of the CLL, there was proliferation of the previously noted blast population, which cytochemical studies demonstrated to be of the myeloid series thus indicating acute myeloid leukemia superimposed on CLL. This report presents microscopic, cytogenetic, immunophenotypic, and cytochemical evidence to document the evolution of acute myeloid leukemia in the bone marrow of a patient with CLL after one course of chemotherapy.

Anti-A of donor lymphocyte origin in three recipients of organs from the same donor

The development of iso- and alloantibodies reactive with recipient red blood cells subsequent to organ transplantation is an established phenomenon. However, development of self-reactive antibodies in multiple recipients of organs from a single donor source has only been reported in one instance involving the formation of anti-D after transplantation. We observed the development of a delayed hemolytic transfusion reaction 10 days after transplantation of a group O liver into a group A recipient. Serologic studies revealed a positive direct antiglobulin test due to coating of autologous A cells with anti-A. Close follow-up of the group A recipients of the kidneys transplanted from the same group O donor revealed development of hemolysis secondary to anti-A on day 11 in one recipient and hemolysis due to anti-A on day 13 in a second recipient. Significant anemia, a 2-3 g/dl drop in hemoglobin, occurred in both kidney recipients. These findings suggest that recipient of organs from donors whose transferred lymphocytes have produced antirecipient RBC antibodies in another recipient may be at risk for developing a similar self-limited hemolytic episode and should be followed accordingly.

Platelet dysfunction associated with Wilms tumor and hyaluronic acid

Acquired von Willebrand disease (AVWD) has been described in two cases of nephroblastoma. We studied a patient with nephroblastoma who presented with a coagulopathy suggestive of AVWD. The subject had undetectable levels of F.VIIIR:Ag, diminished F.VIIIR:WF (16.3%), F.VIII:C activity (37%), and lack of platelet aggregation to ADP, epinephrine, collagen, and arachidonic acid. These results were associated with abnormally high serum levels (850 mg/dl) of hyaluronic acid (HA), which made the patient's serum hyperviscous. Examination of the neoplasm revealed HA in the tumor matrix. All abnormalities of coagulation resolved after chemotherapy and extirpation of the neoplasm, which produced normal serum HA levels. To study the effects of HA on platelet function, we added HA to normal platelet-poor plasma (NPP), which rendered F.VIIIR:Ag undetectable; treatment of HA with hyaluronidase eliminated F.VIIIR:Ag assay interference caused by HA. F.VIII:C activity decreased in vitro when HA was mixed with normal platelet-poor plasma (NPP). HA reduced the initial slope of normal platelet aggregation. Partial correction of platelet aggregation occurred after hyaluronidase treatment of HA-spiked PRP. Experiments in rabbits exposed to HA (serum level 400 mg/dl) demonstrated abnormalities similar to those noted in the patient. Shear rate studies of whole blood containing HA (500 mg/dl) yielded high shear stress, 27-136 dynes/cm2 over shear rates of 10-216 sec-1. We conclude that the coagulopathy demonstrated in this case is secondary to hyperviscosity produced by elevated levels of HA, which interferes with the assay for F.VIIIR:Ag. Thus the acquired coagulopathy associated with other cases of nephroblastoma may present as spurious von Willebrand disease.

Immune anti-A1 in A2 recipients of kidneys from group O donors

Antibodies specific for recipient red cell antigens have been demonstrated in patients who receive organs from ABO unmatched donors. In some cases, severe but self-limited hemolysis has been associated with the development of posttransplantation antibodies. We report a case in which an A2 recipient of a kidney from a group O donor formed anti-A1 antibody which reacted with homologous red cells. The patient developed a delayed hemolytic transfusion reaction. A radiochromium survival study revealed decreased survival of A1 red cells. A broader specificity of the antibody was not shown during follow-up. The anti-A1 was not detected in a sample tested 6 months after the initial study. It is probable that the anti-A1 noted in this case was formed by passenger lymphocytes. A2 patients who develop anti-A1 after renal transplantation should be transfused with red cells negative for A1.

Harvest of young red cells on an automated cell separator

Red cells can be fractionated by age on a blood processor (Model 2991, IBM). However, little data exist on processing a product for transfusion. This report details a method for collecting young erythrocyte (YE) units containing a mean hemoglobin content of 56.43 +/- 1.39 (SEM) grams. Enrichment with YEs was indicated by greater activity of the enzyme pyruvate kinase (PK) in aliquots of YE units. The mean ratio of PK activity in the young red cell product compared to unfractionated blood was 1.14 +/- 0.03 (SEM). An increased PK ratio was noted in 23 of 26 units studied. Based on the PK ratio, the mean age of the erythrocytes was 46 days, compared to 60 days for standard units of blood. In the 6 units assayed, the reticulocyte count was increased. Collection of YE units was relatively easy, no untoward donor reactions were observed, and no deleterious effects developed in the recipient. Although these data suggest enrichment with a young population of red cells, YE units produced by this method are experimental. Routine use of this procedure awaits demonstration of a significant decrease in transfusion frequency in patients receiving YE units for chronic red cell therapy.

Ex vivo selective isolation of young red blood cells using the IBM-2991 cell washer

Transfusion-induced hemochromatosis is a major complication in the therapy of severe chronic anemia. Improvement of transfused cell survival with a reduction in transfusion frequency is one possible approach to this problem. Using continuous-flow centrifugation (CFC), young red blood cells (YRBC) with enhanced in vivo survival have been isolated, but the expense and donor time required with this technique prohibit its widespread use for patient support. We studied the use of the IBM 2991 cell washer (CW) to isolate YRBC ex vivo from previously collected donor blood. Age-dependent red cell separation could be achieved using this instrumentation. Autologous mean red cell half-life (RBC-T50) (n = 9) for the younger cell fractions was 43.9 +/- 7.8 days compared to 34.7 +/- 5.8 days for the older cell fractions (n = 6, p less than 0.05). Paired measurement of RBC-T50 for young and old fractions in three donors showed an average survival increase of 41% for the YRBC. Adequate quantities of YRBC with enhanced survival can be obtained with less cost and less donor stress using the CW system compared to CFC. This approach could improve the management of patients with chronic transfusion requirements and merits further examination.

Rh mosaicism and aberrant MNSs antigen expression in a patient with chronic myelogenous leukemia

This is, to our knowledge, the first report of combined Rh and MNSs antigen alteration in a leukemic patient. Red blood cells of a chronic myelogenous leukemia patient demonstrated mixed field reactions with anti-Rho (D) reagents in August 1980. Earlier tests indicated he was Rho (D) positive in 1967, but Rho (D) and Du negative from 1973 to 1980. Titration studies with anti-hr' (c) and anti-hr" (e) indicated depressed expression, and there was also very weak s expression. One hundred per cent of cells studied from 1967 to 1980 were Philadelphia chromosome (Ph1) positive. No abnormalities in chromosomes associated with the Rh or MNSs blood groups 1 and 4, respectively, were noted. Phenotypes from August 1980 through September 1981 revealed normalization of red blood cell antigen status with an increase of Rho (D) positive cells from 35% to 100%. Chromosomal studies in October, 1980 and June, 1981 revealed Ph1 mosaicism with 25 and 75% Ph1 negative cells, respectively. These findings suggest that normalization of previously altered red blood cell antigen expression may reflect resurgence of normal stem cell lines.

Disseminated Petriellidium boydii and pacemaker endocarditis

Clinical and morphologic findings are described in a 62 year old woman with "mixed connective tissue disease" who received corticosteroid therapy, and in whom disseminated and fatal Petriellidium boydii infection with right-sided endocarditis developed. The patient was a gardener. The organism is ubiquitous in soil in many part of the United States; therefore, it is likely that the infection was introduced by this means. Endocarditis due to P. boydii has not been reported previously. In the patient described, massive vegetations nearly obliterated the tricuspid valve orifice, encasing a pacemaker catheter which had been inserted eight years earlier. Although never previously isolated from blood cultures, P. boydii was isolated from 11 consecutive blood cultures. P. boydii is a true fungus and has only recently been appreciated as an opportunistic pathogen in a compromised host.

Hemochromatosis heart disease: an unemphasized cause of potentially reversible restrictive cardiomyopathy

Cardiac involvement in hemochromatosis typically results in congestive cardiomyopathy; a restrictive cardiomyopathy due to hemochromatosis is distinctly rare. A restrictive cardiomyopathy, which developed in the patient described in this report, was due to hemochromatosis which mimicked constrictive pericarditis clinically, echocardiographically and hemodynamically, and resulted in a thoracotomy for attempted surgical therapy. The fact that hemochromatosis represents the only cause of a restrictive cardiomyopathy that is potentially reversible by medical therapy makes early recognition of hemochromatosis heart disease important.