Is increased mortality associated with post-operative infections after leukocytes containing red blood cell transfusions in cardiac surgery? An extended analysis

In two randomized trials in cardiac surgery we observed that leukoreduced allogeneic red blood cell (RBC) transfusions (LR) compared with standard buffy-coat-depleted RBC transfusions (BCD) resulted in lower rates of post-operative infections and mortality. To unravel whether this comprises two independent side effects or could be related complications of allogeneic leukocytes, we performed a re-analysis on the patients of these two trials. For all analyses, homogeneity tests were shown not to be significant. Data on characteristics of post-operative infections, nature of microorganisms, number of transfusions and causes of death in both studies were subjected to an integrated analysis. In both studies combined, 1085 patients had been assigned to prestorage leukoreduced RBCs (LR, n= 542) or standard buffy-coat-depleted RBCs (BCD, n= 543). Post-operative infections were significantly higher in the BCD group [BCD: 34.2% vs. LR: 24.0%, common odds ratios (COR): 1.65, 95% confidence interval (CI): 1.27-2.15], whereas the species of cultured microorganisms and the type of the infections were similar in both randomization arms. Mortality with infections was significantly higher in patients receiving BCD compared with LR (BCD: 5.5% vs. LR: 2.2%, COR: 2.59, 95% CI: 1.31-5.14), whereas mortality without infections was similar in both arms (BCD: 3.9% vs. LR: 3.1%, COR: 1.24, 95% CI: 0.65-2.38). The only cause of death that differed significantly between BCD and LR was the combination of multiple organ dysfunction syndrome with infections. This re-analysis shows that transfusion of leukocytes containing RBCs during cardiac surgery may be associated with more infections with fatal outcome. This should be confirmed in a larger extended analysis or a prospective study.

[Ethical discussion on criteria for policy makers in public health authorities for preventative measures against a pandemic caused by a novel influenza A virus]

Federal and regional authorities are currently preparing for a possible influenza pandemic caused by a new human influenza virus subtype. Ethical discussions in the context of such a pandemic were not systematically held within the Public Health scientific community in Germany as yet. This deficit is being approached by the authors. They plea for a systematic conception of a Public Health Ethics framework. Normative benchmarks can be set within such a framework that are more adequate for the discussion than the traditional ethical principles used within medical ethics. Public Health Ethics is an applied ethics that can be utilised for Public Health scientists and policy makers to give them advice and counsel them for a morally acceptable public health practice. The authors present a concise set of ethical principles that are applied in this article to the challenges of an influenza pandemic.

Coagulation parameters of thawed fresh-frozen plasma during storage at different temperatures

Once thawed, fresh-frozen plasma (FFP) should be used, according to guidelines, within 24 h. In hospital practice, this may be associated with wastage. This study has been performed to investigate the coagulation levels of thawed quarantine FFP as used in the Netherlands. Five units of quarantine FFP, obtained by plasmapheresis, were thawed and by sterile docking divided into satellite bags (SB). SB 2-4 were stored at room temperature (RT) for, respectively, 1, 3 and 6 h and SB 5-9 at 4 degrees C for 6, 12 and 24 h and 1 and 2 weeks. At each time point, activated partial thromboplastin time (APTT), prothrombin time (PT), fibrinogen, factor V (FV), factor VIII (FVIII) and ADAMTS13 activity were measured. During storage at RT for up to 6 h, no major differences were found in the levels of FV, PT, fibrinogen and ADAMTS13 activity. FVIII activity showed a decrease of 16% and the APTT was prolonged by 6%. During storage at 4 degrees C for 2 weeks, FV and FVIII were reduced by 35 and 45%, respectively. The APTT and PT were prolonged by 17 and 15%, respectively. Fibrinogen was decreased by 8%. No change in ADAMTS13 activity was found. FFP stored at RT for 6 h or at 4 degrees C for 2 weeks can provide sufficient support for adequate haemostasis except for patients with a known deficiency for FVIII and can be used for plasmapheresis in patients with thrombotic thrombocytopenic purpura (TTP).

Noninvasive antenatal management of fetal and neonatal alloimmune thrombocytopenia: safe and effective

OBJECTIVE

To describe the outcome of pregnancies with fetal and neonatal alloimmune thrombocytopenia (FNAIT) in relation to the invasiveness of the management protocol.

DESIGN

Retrospective analysis of prospectively collected data from a national cohort.

SETTING

Leiden University Medical Centre, the national centre for management of severe red cell and platelet alloimmunisation in pregnancy.

POPULATION

Ninety-eight pregnancies in 85 women with FNAIT having a previous child with thrombocytopenia with (n= 16) or without (n= 82) an intracranial haemorrhage (ICH).

METHODS

Our management protocol evolved over time from (1) serial fetal blood samplings (FBS) and platelet transfusion (n= 13) via (2) combined FBS with maternal intravenous immunoglobulins (n= 33) to (3) completely noninvasive treatment with immunoglobulins only (n= 52 pregnancies, resulting in 53 neonates). Perinatal outcome was assessed according to the three types of management.

MAIN OUTCOME MEASURES

Occurrence of ICH, perinatal survival, gestational age at birth and complications of FBS.

RESULTS

All but one of 98 pregnancies ended in a live birth; none of the neonates had an ICH. The median gestational age at birth was 37 weeks (range 32-40). In groups 1 and 2, three emergency caesarean sections were performed after complicated FBS, resulting in two healthy babies and one neonatal death.

CONCLUSION

Noninvasive antenatal management of pregnancies complicated by FNAIT appears to be both effective and safe.

Public Health Genomics

Which consequences can be drawn from genome-based knowledge and how can it be responsibly and timely translated into policies and practice? What are recent developments in genetics and molecular biology, what are the challenges, what are the risks of these developments? Which policies can provide an acceptable balance between providing strong protection of individuals'interests and needs while enabling society to benefit from the genomic advances and empowering individuals? How can molecular medicine contribute to more effective and efficient health care services, and what infrastructures and policies can already now be implemented to assure a benefit for population health? Thus, Public Health Genomics (PHG) tries to answer these challenging questions. This integration of genomics into the aims of public health is called Public Health Genomics (PHG) and is defined as "the responsible and effective translation of genome-based knowledge and technologies into public policy and health services for the benefit of population health".

Efficacy, safety and user-friendliness of two devices for postoperative autologous shed red blood cell re-infusion in elective orthopaedic surgery patients: A randomized pilot study

To determine the safety, efficacy and user-friendliness of two different postoperative autologous blood re-infusion systems, an open, randomized, controlled study was performed. Eligible consecutive primary and revision total hip and knee replacement patients were randomized for one of the two systems or for a control group in which shed blood was not re-infused. The nursing staff scored user-friendliness. Patients were monitored after re-infusion. In all three patient groups, a restrictive transfusion trigger was used. Sixty-nine of 70 randomized patients were evaluated. Ease of use, efficacy and safety of both re-infusion systems were comparable. There was no difference in allogeneic blood use between the groups. Thirty per cent of the patients re-infused with autologous blood developed a mainly mild, febrile transfusion reaction. No other adverse reactions were seen. Signs of coagulopathy after re-infusion were not found. In multivariate analysis, autologous re-infusion was an independent factor associated with a shorter hospital stay. Both postoperative autologous blood re-infusion systems were of equal efficacy and safety. The contribution of autologous wound blood re-infusion to reduce allogeneic transfusions must be investigated in a larger study.

[Genetics in health research and public health]

Public health practice has to date concerned itself mostly with environmental determinants of health and disease and has paid scant attention to genetic variations within the population. The advances brought about by genomics is changing these perceptions. Many predict that this knowledge will enable health promotion messages and disease prevention programmes to be specifically directed at susceptible individuals or at subgroups of the population, based on their genetic profile. Obviously, the integration of genomics into public health research, policy and practice will be one of the most important future challenges that our health care systems will face. In this context, Public Health Genomics (PHG), defined as the responsible and effective translation of genome-based knowledge and technologies into public policy and health services for the benefit of population health, will encounter these chances and challenges.

Differential sensitivities of pathogens in red cell concentrates to Tri-P(4)-photoinactivation

BACKGROUND AND OBJECTIVES

Photodynamic treatment (PDT) with the cationic porphyrin, mono-phenyl-tri-(N-methyl-4-pyridyl)-porphyrin chloride [Tri-P(4)], has previously been shown to be effective at inactivating vesicle stomatitis virus (VSV) in red cell concentrates (RCC) with limited damage to red blood cells (RBC). The aim of this study was to determine the pathogen-inactivating capacity of PDT with Tri-P(4) for a broader range of pathogens and to establish the associated effect on in vitro RBC quality.

MATERIALS AND METHODS

A series of viruses and bacteria was spiked into 60% RCC. Pathogen inactivation was determined after PDT with 25 microm Tri-P(4) and red light up to 360 kJ/m2. Human immunodeficiency virus (HIV)-infected cells were evaluated for cell death induction, and RCC were analysed for the induction of haemolysis and ATP content.

RESULTS

For the lipid-enveloped viruses bovine viral diarrhoea virus, HIV and pseudorabies virus, and for the Gram positive bacterium, Staphylococcus aureus, and the Gram-negative bacteria, Pseudomonas aeruginosa and Yersinia enterolitica, inactivation of > or = 5 log10 was measured after 60 min of PDT with Tri-P(4). The required treatment time to achieve this level of inactivation was four times longer than required for VSV. For cell-associated HIV, only 1.7 log10 of inactivation was found, despite clear induction of cell death of HIV-infected cells. The non-enveloped virus, canine parvovirus, was completely resistant to the treatment. PDT of RCC with Tri-P(4) for 60 min, and subsequent storage in AS-3, resulted in 4% haemolysis after 35 days of storage. The ATP content of untreated and treated RBC declined with similar kinetics during storage.

CONCLUSION

PDT of RCC with Tri-P(4) for 60 min inactivates a wide range of pathogens, but not cell-associated HIV and a non-enveloped virus, and compromises RBC quality. This reduces the suitability of PDT with Tri-P(4) for red cell sterilization. Therefore, further improvements in the treatment procedures to potentiate pathogen inactivation and to preserve RBC integrity will be required to generate an effective treatment for sterilizing RCC.

Vaginal delivery for fetuses at risk of alloimmune thrombocytopenia?

OBJECTIVES

To evaluate the safety of vaginal delivery in pregnancies with fetal and neonatal alloimmune thrombocytopenia (FNAIT).

DESIGN

Prospective data collection.

SETTING

Leiden University Medical Centre, the national centre for management of severe red cell and platelet alloimmunisation.

POPULATION

Thirty-two pregnancies with FNAIT, with a sibling with thrombocytopenia but without an intracranial haemorrhage (ICH).

METHODS

The mode of delivery, platelet count in cord blood and neonatal outcome were analysed. All women received weekly intravenous immunoglobulin from 32 to 38 weeks of gestation. Head ultrasound scan was performed in all neonates.

MAIN OUTCOME MEASURES

Signs of ICH or other bleeding in the neonates.

RESULTS

Twenty-three women delivered vaginally. Nine caesarean sections were performed, all for obstetric reasons. Median platelet count at birth was 142 x 10(9)/l (range, 4-252 x 10(9)/l), with severe thrombocytopenia (<50 x10(9)/l) in four neonates, of which three were born vaginally. None of the neonates showed signs of ICH or other bleeding.

CONCLUSIONS

In pregnancies with FNAIT and a thrombocytopenic sibling without ICH, vaginal delivery was not associated with neonatal intracranial bleeding. These initial results support our noninvasive management of these pregnancies with FNAIT.

Event-related theta oscillations during working memory tasks in patients with schizophrenia and healthy controls

Altered frontal lobe activity and executive control associated with working memory (WM) dysfunction are recognized as core deficits in schizophrenia. These impairments have been discussed as being associated with deficits in self-regulated action monitoring and anticipatory action plan generation. To study electrophysiological correlates of executive control -- specifically action monitoring and action rule switching -- under varying WM load, we used a paradigm derived from classic N-back (WM) tasks and requiring monitoring of simple actions. We focused on event-related changes in post-stimulus theta oscillatory activity during varying cognitive and WM demand in healthy controls and schizophrenia patients. The results show significant WM load and rule-switching-related increases of post-stimulus theta amplitude at fronto-central locations in controls. In patients with schizophrenia, there was no such modulation, but -- apart from an increased early theta at left temporal locations -- generally reduced late theta responses in all tasks and at all locations. Furthermore, the patients with schizophrenia showed significant differences in their error patterns, which imply differences in automation and anticipation of actions between controls and patients. These findings suggest that theta oscillations are involved in mediating frontal lobe activity and functions related to enhanced executive control. We conclude that the patients with schizophrenia showed deficits in acquiring a mental task set which appear to be associated with impairments in action monitoring and task-specific regulation of executive control.

Interlaboratory comparison of red-cell ATP, 2,3-diphosphoglycerate and haemolysis measurements

BACKGROUND AND OBJECTIVES

Red blood cell (RBC) storage systems are licensed based on their ability to prevent haemolysis and maintain RBC 24-h in vivo recovery. Preclinical testing includes measurement of RBC ATP as a surrogate for recovery, 2,3-diphosphoglycerate (DPG) as a surrogate for oxygen affinity, and free haemoglobin, which is indicative of red cell lysis. The reproducibility of RBC ATP, DPG and haemolysis measurements between centres was investigated.

MATERIALS AND METHODS

Five, 4-day-old leucoreduced AS-1 RBC units were pooled, aliquotted and shipped on ice to 14 laboratories in the USA and European Union (EU). Each laboratory was to sample the bag twice on day 7 and measure RBC ATP, DPG, haemoglobin and haemolysis levels in triplicate on each sample. The variability of results was assessed by using coefficients of variation (CV) and analysis of variance.

RESULTS

Measurements were highly reproducible at the individual sites. Between sites, the CV was 16% for ATP, 35% for DPG, 2% for total haemoglobin and 54% for haemolysis. For ATP and total haemoglobin, 94 and 80% of the variance in measurements was contributed by differences between sites, and more than 80% of the variance for DPG and haemolysis measurements came from markedly discordant results from three sites and one site, respectively. In descending order, mathematical errors, unvalidated analytical methods, a lack of shared standards and fluid handling errors contributed to the variability in measurements from different sites.

CONCLUSIONS

While the methods used by laboratories engaged in RBC storage system clinical trials demonstrated good precision, differences in results between laboratories may hinder comparative analysis. Efforts to improve performance should focus on developing robust methods, especially for measuring RBC ATP.

Splenectomy for the treatment of thrombotic thrombocytopenic purpura

Plasma exchange is the treatment of choice for patients with thrombotic thrombocytopenic purpura (TTP) and results in remission in >80% of the cases. Treatment of patients who are refractory to plasma therapy or have relapsing disease is difficult. Splenectomy has been a therapeutic option in these conditions but its value remains controversial. We report on a series of 33 patients with TTP who were splenectomised because they were plasma refractory (n = 9) or for relapsed disease (n = 24). Splenectomy generated prompt and unmaintained remissions in all except five patients, in whom remission was delayed (n = 4) or who died with progressive disease (n = 1). Four postoperative complications occurred: one pulmonary embolism and three surgical complications. Median follow-up after splenectomy was 109 months (range 28-230 months). The overall postsplenectomy relapse rate was 0.09 relapses/patient-year and the 10-year relapse-free survival (RFS) was 70% (95% CI 50-83%). In the patients with relapsing TTP, relapse rate fell from 0.74 relapses/patient-year before splenectomy to 0.10 after splenectomy (P < 0.00001). Two patients died from first postsplenectomy relapse. Although these results are based on retrospective data and that the relapse rate may spontaneously decrease with time, we conclude that splenectomy, when performed during stable disease, has an acceptable safety profile and should be considered in cases of plasma refractoriness or relapsing TTP to reach durable remissions and to reduce or prevent future relapses.

Cost-effectiveness of leucocyte-depleted erythrocyte transfusion in cardiac valve surgery

Cost-effectiveness of leucodepleted erythrocytes (LD) over buffy-coat-depleted packed cells (PC) is estimated from the primary dataset of a recently reported randomized clinical trial involving valve surgery (+/-CABG) patients. Data on the patient level of 474 adult patients who were randomized double-blind to LD or PC were used in order to calculate the healthcare costs and longevity per patient. The incremental cost-effectiveness ratio (ICER) in net costs per life-year gained was established from the healthcare perspective. Bootstrapping and cost-effectiveness acceptability curves were used in order to determine the confidence interval (CI) of the ICER. The longevity of patients in the PC and LD group was 10.6 and 11.4 years, respectively. Relative to PC, LD yielded an estimated 0.8 (95% CI = -0.27 to 1.84) life-year in the baseline. Adjusted for age and sex differences, health gains for LD are 0.4 life-year gained (95% CI = -0.67 to 1.44). Healthcare costs per patient averaged 10163 US dollars per patient in the PC group and 9949 US dollars in the LD group. Average cost-savings were 214 US dollars (95% CI = -1536 to 1964) per patient. Acceptability curves constructed from bootstrap simulations showed a probability of being cost-saving of 59% for universal leucodepletion from the healthcare perspective. The probability of adopting leucodepletion regardless of the costs reaches 92.7%. LD in patients receiving four or more transfusions showed the highest cost-savings and health gains. Leucodepletion of erythrocytes is a cost-saving strategy in cardiac valve (+/-CABG) patients. However, probablistic analysis failed to show a significant difference with buffy-coat-depleted PC.

Compliance with prophylactic platelet transfusion trigger in haematological patients

The aim of prophylactic platelet transfusions in haemato-oncologic patients with thrombocytopenia is to prevent bleeding. Currently, a platelet transfusion trigger of 10 x 10(9) L(- 1) is considered to be safe. Transfusion compliance with this trigger can save costs. To investigate the compliance with this trigger of 10 x 10(9) L(- 1), we have evaluated 1447 platelet transfusions given during a period of 1 year to haematological patients. In half of the transfusions, there had been compliance with the trigger of 10 x 10(9) L(- 1). About three-quarters of all platelet transfusions were given at platelet counts < or =20 x 10(9) L(- 1). Transfusions at levels >20 x 10(9) L(- 1) were usually performed because of bleeding, scheduled interventions or concurrent anticoagulant therapy. We conclude that compliance with the prophylactic platelet transfusion trigger of 10 x 10(9) L(- 1) was about 50%; however, deviation from the trigger was partly explained by risk factors that justify a higher transfusion trigger.

[Activity loss of Von Willebrand factor cleaving protein (ADAMTS-13) is diagnostic for primary and pregnancy-related thrombotic thrombocytopenic purpura]

OBJECTIVE

To determine whether the measurement of the Von Willebrand factor cleaving protease ADAMTS-13, such as is carried out at the University Medical Centre of Utrecht, The Netherlands, contributes towards the diagnosis and treatment of patients with thrombotic thrombocytopenic purpura (TTP).

DESIGN

Descriptive.

METHOD

In a group of 98 patients from 21 hospitals, with a Coombs-negative haemolytic anaemia and thrombocytopenia, the ADAMTS-13 activity was measured. Treatment was given irrespective of ADAMTS-13 activity.

RESULTS

ADAMTS-13 activity was absent in 27 of 29 patients diagnosed with primary TTP and in all 5 pregnancy-TTP patients. In patients suffering from TTP after bone marrow transplantation (post-BMT) and in all other patients included in this study, ADAMTS-13 activity was normal. Of the 32 patients with absent ADAMTS-13 activity, 28 underwent plasmapheresis. This treatment proved effective as all 28 patients responded well. 17 patients with normal ADAMTS-13 activity also underwent plasmapheresis; 5 (30%) responded well to treatment. In 2 cases a final diagnosis of primary TTP was made, in a further 2, haemolytic uraemic syndrome and in 1 case sepsis was diagnosed.

CONCLUSION

In this study, the absence of ADAMTS-13 activity predicted primary TTP and TTP of pregnancy with a sensitivity of 93% and a specificity of 100%. Absence of ADAMTS-13 activity is a strong indication for plasma exchange.

Effect of maternal anti-HPA-1a antibodies and polyclonal IVIG on the activation status of vascular endothelial cells

Maternal anti-HPA-1a antibodies can cause severe fetal and neonatal alloimmune thrombocytopenia (FNAIT), complicated by intracranial haemorrhage (ICH). Antenatal treatment with maternal intravenous immunoglobulin (IVIG) seems to protect against ICH even when thrombocytopenia persists. The aim of this study was to investigate if anti-HPA-1a antibodies and IVIG potentially affect vascular endothelial cells (ECs) in order to identify susceptibility for ICH. Human umbilical cord endothelial cells (HUVEC) were incubated with anti-HPA-1a antibodies with or without polyclonal IVIG and evaluated for EC activation. Maternal sera with anti-HPA-1a antibodies affected neither the EC expression of intracellular adhesion molecule-1 (ICAM-1), vascular adhesion molecule-1 (VCAM-1) and tissue factor (TF) nor the release of van Willebrand factor (vWF) or interleukin (IL)-8 nor the integrity of ECs. Maternal sera obtained after IVIG treatment and polyclonal IVIG decrease constitutive and cytokine-induced ICAM-1 and VCAM-1 expression on ECs. The results show that maternal anti-HPA-1a antibodies cause no activation or damage of ECs in this model. The clinical relevance of the de-activating properties of IVIG on EC activation with respect to ICH deserves further investigation.

Double-Blind, Randomized Controlled Trial on the Effect of Leukocyte-Depleted Erythrocyte Transfusions in Cardiac Valve Surgery

BACKGROUND

Leukocytes in allogeneic blood transfusions are believed to be the cause of immunomodulatory events. A few trials on leukocyte removal from transfusions in cardiac surgery have been conducted, and they showed inconclusive results. We found in a previous study a decrease in mortality rates and number of infections in a subgroup of more heavily transfused patients.

METHODS AND RESULTS

Patients (n=496) undergoing valve surgery (with or without CABG) were randomly assigned in a double-blind fashion to receive standard buffy coat-depleted (PC) or prestorage, by filtration, leukocyte-depleted erythrocytes (LD). The primary end point was mortality at 90 days, and secondary end points were in-hospital mortality, multiple organ dysfunction syndrome, infections, intensive care unit stay, and hospital stay. The difference in mortality at 90 days was not significant (PC 12.7% versus LD 8.4%; odds ratio [OR], 1.52; 95% confidence interval [CI], 0.84 to 2.73). The in-hospital mortality rate was almost twice as high in the PC group (10.1% versus 5.5% in the LD group; OR, 1.99; 95% CI, 0.99 to 4.00). The incidence of multiple organ dysfunction syndrome in both groups was similar, although more patients with multiple organ dysfunction syndrome died in the PC group. LD was associated with a significantly reduced infection rate (PC 31.6% versus LD 21.6%; OR, 1.64; 95% CI, 1.08 to 2.49). In both groups, intensive care unit stay and hospital stay were similar, and postoperative complications increased with the number of transfused units.

CONCLUSIONS

Mortality at 90 days was not significantly different; however, a beneficial effect of LD in valve surgery was found for the secondary end points of in-hospital mortality and infections.

Escherichia coli-nitroreductase suicide gene control of human telomerase reverse transcriptase-transduced minor histocompatibility antigen-specific cytotoxic T cells

Adoptive immunotherapy with ex vivo generated cytotoxic T lymphocytes (CTLs) is applied for the treatment of leukemia relapses or viral infections after allogeneic stem cell transplantation. A common problem of adoptive immunotherapy strategies is the ex vivo expansion of the generated T cells to sufficient numbers. CTLs can be efficiently expanded by ectopic expression of the human telomerase gene (hTert). However, hTert transduction may also increase the chance for malignant transformation. Therefore, we explored the feasibility of suicide gene control of ex vivo generated CTLs expanded through the ectopic expression of hTert. To this end, we compared the efficacy of the new Escherichia coli-nitroreductase (E. coli-Ntr) suicide gene with the well-known herpes simplex virus-thymidine kinase (HSV-Tk). Introduction of hTert provided the transduced CTLs with a distinct growth advantage over the nontransduced CTLs. The hTert-E. coli-Ntr double-transduced CTLs retained their antigen-specific functions. Treatment of hTert-E. coli-Ntr double-transduced CTLs with metronidazole significantly inhibited the proliferation to a similar extent to the treatment of hTert-HSV-Tk double-transduced CTLs with ganciclovir. This is the first application of the E. coli-nitroreductase gene for the elimination of human T cells with metronidazole.