Detection of volume loss using the Nexfin device in blood donors.

We investigated which haemodynamic parameters derived from Nexfin non-invasive continuous arterial blood pressure measurements are optimal to detect controlled volume loss in spontaneously breathing subjects. Haemodynamic monitoring was performed in 40 whole-blood donors. Mean arterial pressure, cardiac index, systemic vascular resistance index and pulse pressure variation were recorded during controlled breathing, and a Valsalva manoeuvre was performed before and after blood donation. Blood donation resulted in a reduction in cardiac index (from 3.96 ± 0.84 l.min(-1) .m(2) to 3.30 ± 0.61 l.min(-1) .m(2) ; p < 0.001), an increase in systemic vascular resistance (from 1811 ± 450 dyn.s.cm(-5) .m(2) to 2137 ± 428 dyn.s.cm(-5) .m(2) ; p < 0.001) and an increase in pulse pressure variation (from 13.4 ± 5.1 to 15.3 ± 5.4%; p = 0.02). The area under the receiver operating characteristic curve to detect volume loss was highest for cardiac index (0.94, 95% CI 0.88-0.99) and systemic vascular resistance (0.90, 95% CI 0.82-0.99). Nexfin is a non-invasive haemodynamic monitor that can feasibly detect volaemic changes in spontaneously breathing subjects.

Bone density in apheresis donors and whole blood donors.

Apheresis donation using citrate causes acute decrease in serum calcium and increase in serum parathyroid hormone. Long-term consequences, such as decrease in bone mineral density (BMD), are not known. In this study, we compared the BMD of 20 postmenopausal apheresis donors (mean donation number 115 times in up to 15 years) with that of 20 whole blood donors (for 15 years or more) aged 55-70. BMD in the lumbar spine was not lower in apheresis donors than in blood donors (mean ± SD 1.00 ± 0.18 vs. 0.92 ± 0.12, P = 0.09). In the hip, BMD was not different between the groups.

Satisfaction of Paediatric Oncology Patients, Survivors, and Nurses with the Position of Their Totally Implantable Venous Access Port (SPACE-Study).

BACKGROUND: To compare paediatric oncologic vascular access ports located on the anterior thoracic wall to ports on the lower lateral thoracic wall, in terms of perceived port-related hindrance and scar-quality. METHODS: A cross-sectional survey study including paediatric oncology patients (≥8-<19 yrs), caregivers (in patients <8 yrs), survivors (>22 yrs with only anterior ports) and nurses of the Princess Máxima Center, the Netherlands, was performed. The survey consisted of questions regarding satisfaction, hindrance during daily life, and port position preference. For survivors, scar-quality was assessed using the validated Patient and Observer Scar Assessment Scale (POSAS 2.0); a high score (i.e., a displeasing scar) was defined as a score higher than the third quartile of the median for that question. RESULTS: In total, 147 participants were included; 83 patients/caregivers, 31 survivors, and 33 nurses. Overall, 81 % was satisfied with the position of their port. Satisfaction, hindrance and complications did not differ between anterior and lower lateral ports. For the anterior position, minimal pressure on the port during daily life was a mentioned reason to prefer this position. For the lower lateral position, less visibility of the scar and easiest access were mentioned. Of all survivors with an anterior port scar, one in five had a displeasing scar and all scars observed were widened. Female patients preferred a lower lateral port, and scar-quality was better for left-sided port scars. CONCLUSION: The port position should be chosen together with patients/caregivers based on the (dis-)advantages of each position, as identified by this study. LEVEL OF EVIDENCE: II.

An ultrapure plasma-derived monoclonal antibody-purified factor IX concentrate (Nonafact®), results of phase III and IV clinical studies.

Nonafact(®), an ultrapure, monoclonal antibody-purified factor IX concentrate (FIX) was developed to minimize risk of thrombotic complications and viral transmission. To investigate the pharmacokinetics, efficacy and safety, phase III/IV studies were performed in the Netherlands and Poland from 1996 to 2007. The mean half-life, in vivo response and recovery of Nonafact(®) were 18.7 (SD 2.0) h, 1.1 (SD 0.2) IU dL(-1) per IU kg(-1) b.w. of FIX infused and 49% (SD 10%), respectively. Eleven surgical procedures were performed in eight patients. During two surgeries, both high-risk, blood loss was observed. No postoperative bleeding occurred. The in vivo recovery of FIX was higher than expected. In the phase III follow-up study, 26 previously treated patients (PTP) were included with a median follow-up of 1130 days. From the 1617 minor bleedings, 80.5% was stopped after a single infusion. In the phase IV study thirteen patients were treated for a median study period of 737 days. In the two follow-up studies the investigators rated the effect of Nonafact(®) as excellent/good in 95% of major bleedings. Surgeries for which Nonafact(®) was given prophylactically were without bleeding problems. In total more than 10 million units of Nonafact(®) were used during almost 120 person-years. Only one minor adverse event was reported. No inhibitors, viral transmissions and thrombogenic events occurred. In conclusion, Nonafact(®) is safe and provides excellent haemostasis in haemophilia B patients treated for spontaneous bleeding or undergoing surgical procedures. Due to the excellent in vivo recovery characteristic, treatment with Nonafact(®) is cost saving compared to other FIX products.

Bacterial screening of platelet concentrates: results of 2 years active surveillance of transfused positive cultured units released as negative to date.

BACKGROUND: The BacT/ALERT system for bacterial monitoring of platelet concentrates (PCs) was introduced in the Netherlands in 2001. Samples are cultured for 7 days, and as a result of the short shelf-life of PCs, they are usually released as 'negative to date'. Therefore, some of the PCs have already been transfused at the moment of a positive signal in continued cultures in the BacT/Alert. It is unclear, however, whether these PCs are associated with more transfusion reactions. METHODS: During a 2-year period clinical data were collected from all patients who received PCs released as 'negative to date' but with a positive bacterial culture after being transfused. RESULTS: Data of 158 patients who received PCs with confirmed positive bacterial culture tests were analysed. Two patients developed a transfusion reaction. In both PCs, Propionibacterium was cultured. The imputability as related to the transfusion was classified as unlikely in both patients. CONCLUSION: Two of 158 transfusions of PCs released as 'negative to date', but with a confirmed positive BacT/ALERT result, were initially associated with transfusion reactions. However, the imputability of both reactions was low.

Elevated levels of FVIII:C within families are associated with an increased risk for venous and arterial thrombosis.

Elevated levels of coagulation factor VIII:C (FVIII:C) are associated with an increased risk for venous and arterial thromboembolism. Whether relatives of patients with elevated levels of FVIII:C are also at increased risk for thrombotic disease is unknown. The objective was to determine the annual incidences of both venous and arterial thrombotic events in first-degree relatives of patients with elevated levels of FVIII:C and venous thromboembolism (VTE) or premature atherosclerosis. A retrospective study with 584 first-degree relatives of 177 patients with elevated levels of FVIII:C was performed. The level of FVIII:C was determined and relatives with elevated and normal levels of FVIII:C were compared. Of the participants, 40% had elevated levels of FVIII:C. The annual incidence of a first episode of VTE was 0.34% and 0.13% in relatives with elevated levels of FVIII:C and those with normal levels, respectively [OR 3.7 (95% CI 1.9-7.5)]. The absolute annual incidence in the youngest age group with elevated levels of FVIII:C was 0.16% (0.05-0.37) and gradually increased to 0.99% (0.40-2.04) in those older than 60 years of age, although the odds ratios were not statistically significant. The annual incidences of a first arterial thrombotic event were 0.29% and 0.14% in relatives with and without elevated levels of FVIII:C, respectively [OR 3.1 (1.4-6.6)]. In particular the risks for a first myocardial infarction [OR 4.3 (1.0-18.1); P =0.046] and a first peripheral arterial thrombosis [OR 8.6 (1.6-47.6)] were increased. Within families of patients with elevated levels of FVIII:C and VTE or premature atherosclerosis, 40% of their first-degree relatives has elevated levels of FVIII:C as well, and they are at increased risk for both VTE and arterial thrombosis as compared with their relatives with normal levels.

Antiplatelet and anticoagulant drugs for prevention of restenosis/reocclusion following peripheral endovascular treatment.

BACKGROUND: Peripheral arterial disease (PAD) is frequently treated by balloon angioplasty. Restenosis/reocclusion of the dilated segments occurs often depending on length of occlusion, lower leg outflow, stage of disease and presence of cardiovascular risk factors. To prevent reocclusion, patients are treated with antithrombotic agents. OBJECTIVES: To determine whether any antithrombotic drug is more effective in preventing reocclusion after peripheral endovascular treatment, compared to another antithrombotic drug, no treatment, placebo, or other vasoactive drugs. SEARCH STRATEGY: We searched the Cochrane Peripheral Vascular Diseases Group's trials register (last searched April 2004), the Cochrane Central Register of Controlled trials (CENTRAL Issue 2, 2004), MEDLINE and EMBASE (last searched June 2004). SELECTION CRITERIA: Randomised trials were categorised as A (double or single blinded) or B (not blinded). Participants included patients with symptomatic PAD treated by endovascular revascularisation of the pelvic or femoropopliteal arteries. Interventions were anticoagulant, antiplatelet or other vasoactive drug therapy compared with no treatment, placebo, or any other vasoactive drug. Clinical endpoints were re-obstruction, amputation, death, myocardial infarction, stroke and major bleeding. DATA COLLECTION AND ANALYSIS: Details of the number of randomised patients, treatment, study design, study category, allocation concealment and patient characteristics were extracted. Analysis was based on intention-to-treat data. To examine the effects of binary outcomes such as amputation and major bleeding, odds ratios were computed using a fixed effect model. The 95% confidence intervals of the effect sizes were calculated. MAIN RESULTS: A 60% reduction of recurrent obstruction was found with aspirin (ASA) 330 mg combined with dipyridamol (DIP) as compared to placebo at 12 months follow-up. At six months following endovascular treatment, a positive effect on patency was found with 50 to 100 mg ASA combined with DIP (n = 356). However, this was not significant. ASA/DIP tended towards showing a superior effect on patency after femoropopliteal angioplasty compared with VKA at three, six, and twelve months. Periinterventional treatment with LMWH in femoropopliteal obstructions resulted in significantly lower restenosis/reocclusion rates than with unfractionated heparin. AUTHORS' CONCLUSIONS: Aspirin 50 to 300 mg started prior to femoropopliteal endovascular treatment appears to be the most effective and is safe. Clopidogrel might be an alternative, but data are lacking. Abciximab might be a useful adjunctive for high risk patients with long segmental femoropopliteal interventions. Low molecular weight heparin seems to be more effective in preventing reocclusion or restenosis than unfractionated heparin.

Non-invasive diagnostic work-up of patients with clinically suspected pulmonary embolism; results of a management study.

BACKGROUND: Clinicians often deviate from the recommended algorithm for the diagnosis of pulmonary embolism consisting of ventilation-perfusion scintigraphy and pulmonary angiography. OBJECTIVES: To assess the safety and feasibility of a diagnostic algorithm which reduces the need for lung scintigraphy and avoids the use of angiography. PATIENTS AND METHODS: Consecutive patients with a clinical suspicion of pulmonary embolism were prospectively investigated according to an algorithm in which the diagnosis of pulmonary embolism was excluded after a low clinical probability estimate and a normal d-dimer test result, a normal perfusion scintigraphy result, or a non-high probability scintigraphy result in combination with normal serial ultrasonography of the legs. In these patients anticoagulant treatment was withheld and they were followed up for 3 months to record possible thromboembolic events. During the study period, 923 consecutive patients were seen, of whom 292 were excluded because of predefined criteria. RESULTS: Of the 631 included patients, the diagnosis was refuted on the basis of a low clinical probability estimate and a normal d-dimer test result (95 patients), normal perfusion scintigraphy (161 patients) and non-high probability lung scintigraphy followed by normal serial ultrasonography (210 patients). Of these 466 patients, venous thromboembolic complications during follow-up occurred in six (complication rate 1.3%, 95% confidence interval 0.5, 2.8). The diagnostic protocol was completed in 92% of all included patients. CONCLUSION: The diagnosis of pulmonary embolism can be safely ruled out by a non-invasive algorithm consisting of d-dimer testing combined with a clinical probability estimate, lung scintigraphy, or serial ultrasonography of the legs (in case of non-diagnostic lung scintigraphy).

Can causes of false-normal D-dimer test [SimpliRED] results be identified?

BACKGROUND: To simplify the diagnostic strategy of patients suspected for venous thromboembolism, the use of D-dimer tests has been advocated. Very important for the safety of such diagnostic strategies would be the capacity to recognise false-normal D-dimer results, in order to prevent inadequately withholding anticoagulant treatment in patients who actually have the disease. Insight in the causes of false-normal D-dimer results would therefore be necessary. We hypothesised that certain patient characteristics are associated with relatively low plasma D-dimer levels and, therefore, could increase the risk of false-normal results. METHODS: Consecutive patients with an objectively confirmed venous thromboembolic event and an independently obtained false-normal SimpliRED D-dimer test result were included in the study. For each patient, two controls with objectively confirmed venous thromboembolism and an adequate abnormal D-dimer result were selected. Baseline patient characteristics, obtained by standardised questionnaires, were compared between the two groups of patients. RESULTS: In total, 686 patients had a venous thromboembolic event and 47 of these patients had a false-normal SimpliRED result. Therefore, the overall sensitivity of the SimpliRED test for venous thromboembolism was 94% (95% CI: 92-95%). Although the prevalence of certain clinical characteristics was significantly higher in patients with a false-normal D-dimer result than in the controls [odds ratios for (LMW)heparin treatment and symptoms lasting more than 10 days: 5.1 (95% CI: 1.5-18.7) and 3.2 (95% CI:1.4-7.4), respectively], the prevalence of these characteristics was also high in the control group with an adequate abnormal D-dimer. Combining two or more of these characteristics had a low prevalence and did not further improve the ability to identify those patients with a false-normal D-dimer test at presentation. CONCLUSIONS: Although these findings clearly indicate an association between certain baseline clinical characteristics and the occurrence of a false-normal SimpliRED test, the clinical utility for these characteristics is limited.

[Increased perioperative blood loss during treatment with paroxetine]. / Toegenomen peroperatief bloedverlies bij paroxetinegebruik.

A 63-year-old man who took paroxetine for depression developed massive peroperative haemorrhage during a pancreaticoduodenectomy as a result of paroxetine-induced thrombocytopathy. He lost 4 litres of blood. After administration of 8 units of fresh frozen plasma and 2 times 5 units of thrombocyte concentrate, hemostatic control was obtained and the operation could be continued. Paroxetine is a non-tricyclic serotonin reuptake inhibitor prescribed for the treatment of depression. Since this drug also blocks serotonin reuptake in platelets, a clinically significant platelet dysfunction can occur under certain conditions. Because serotonin promotes platelet aggregation, too low an amount of serotonin in the platelets can result in thrombocytopathy. Before major surgery, it is advised to perform extensive clotting tests if there is any hint of haemorrhagic diathesis in the anamnesis. In case of a prolonged bleeding time, paroxetine treatment should be stopped perioperatively.

Short- and long-acting synthetic pentasaccharides.

Inhibition of activated coagulation factor X (FXa) is an attractive target for antithrombotic treatment strategies, because of the central position of FXa in the coagulation cascade. Most of the now available anticoagulant drugs have inhibitory effects not only on FXa, but also on thrombin. With the development of pentasaccharides, a new class of antithrombotic agents has emerged that acts by specific inhibition of FXa and lacks activity against FIIa. Fondaparinux, the first synthetic short-acting pentasaccharide, has been evaluated, in a large phase II and III clinical programme concerning prophylaxis and treatment of venous thromboembolism and also in phase II studies in patients with acute coronary syndromes. Idraparinux, the long-acting pentasaccharide, has been studied in a dose-finding study in patients with established deep-vein thrombosis and phase III studies are now planned in patients with venous thromboembolism and in patients with atrial fibrillation.

Efficacy of recombinant factor VIIa administered by continuous infusion to haemophilia patients with inhibitors.

We have prospectively monitored treatment of haemophilia patients with inhibitors by recombinant factor VIIa (rFVIIa) administered by continuous infusion to obtain more insight in the underlying factors of the clinical efficacy of this administration method. At present, 43 treatment episodes of 14 different Dutch haemophilia inhibitor patients are included in the database. Analysis of the data showed a discrepancy between the efficacy of rFVIIa continuous infusion treatment of acute and surgical bleeds in the oral cavity [one (14%) effective, two (29%) partially effective, four (57%) not effective] and other parts of the body [29 (80%) effective, four (11%) partially effective, two (6%) not effective, one (3%) impossible to classify]. Patients who had acute or surgical oral cavity bleeds, uncontrolled by rFVIIa continuous infusion, reacted favourably to rFVIIa continuous infusion in other locations of the body. Acute bleeding episodes in the oral cavity, which could not be controlled by rFVIIa continuous infusion, stopped when the treatment regimen was switched to rFVIIa bolus injections. Finally, haemostatic control during dental extractions was excellent after the initial rFVIIa bolus injection preceding the continuous infusion, but rebleeds occurred in all patients within 48 h under rFVIIa continuous infusion coverage. These observations suggest that the efficacy of rFVIIa continuous infusion depends, at least in part, on the location of the body in which the bleeding occurs and that rFVIIa bolus injections are more effective than rFVIIa continuous infusion in the oral cavity. We hypothesize that the inability of rFVIIa continuous infusion treatment to sufficiently inhibit fibrinolysis is the underlying cause of the decreased efficacy of rFVIIa continuous infusion treatment in the oral cavity.

In vivo recovery and safety of human factor VIII product AAFACT in patients with haemophilia A.

AAFACT, a monoclonal purified, solvent/detergent treated human plasma-derived coagulation factor VIII concentrate obtained from plasma of voluntary, non-remunerated blood donors, is manufactured and marketed in the Netherlands by Sanquin Plasma Products since 1995. In a postmarketing surveillance study, 70 previously treated haemophilia A patients were included (73% severe, 14% moderate and 13% mild haemophilia A). Most of these patients were followed during 4 years for the appearance of adverse events, possible transmissions of blood-borne viruses and the occurrence of antibodies against FVIII. The efficacy of treatment was determined in each patient by the in vivo recovery of FVIII. During this study, only six adverse events, possibly related to the use of AAFACT, were reported. None of these were indicated as serious. Transmissions of HIV, HAV, HBV and HCV in the seronegative patients have not been observed. In none of the patients, inhibitors to FVIII were detected. The in vivo recovery of FVIII during this study was not different from the in vivo recovery observed in eight patients during the preregistration study. There was a correlation of in vivo recovery with age and body weight. From these results, we conclude that the clinical usage of this human plasma-derived FVIII product is efficient and safe.