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2.
Stroke ; 48(4): 1085-1087, 2017 04.
Article in English | MEDLINE | ID: mdl-28235962

ABSTRACT

BACKGROUND AND PURPOSE: Cerebral microbleeds (petechial hemorrhages) are a well-known consequence of cerebral amyloid angiopathy and chronic hypertension among other causes. We report 12 patients with a clinically and radiologically distinct microbleed phenomenon in the cerebral white matter. METHODS: These patients were assessed at the University Health Network (Toronto, Canada) between 2004 and 2014. RESULTS: Median age was 40 years (range, 27-63 years), and 7 out of 12 patients were women. All patients had brain magnetic resonance imaging during or immediately after an intensive care unit admission. All patients had respiratory failure, 11 out of 12 received mechanical ventilation, and 3 out of 12 received extracorporeal life support. Magnetic resonance imaging in all 12 patients showed extensive microbleeds, diffusely involving the juxtacortical white matter and corpus callosum but sparing the cortex, deep and periventricular white matter, basal ganglia, and thalami. Several patients also had internal capsule or posterior fossa involvement. CONCLUSIONS: We have described a distinct microbleed phenomenon in the cerebral white matter of patients with critical illness. The specific cause of the microbleeds is unclear, but the pathogenesis may involve hypoxemia as the microbleeds are similar to those described with high-altitude exposure.


Subject(s)
Cerebral Hemorrhage/diagnostic imaging , Corpus Callosum/diagnostic imaging , Critical Illness , White Matter/diagnostic imaging , Adult , Corpus Callosum/blood supply , Female , Humans , Magnetic Resonance Imaging , Male , Middle Aged , Respiration, Artificial , Respiratory Insufficiency , White Matter/blood supply
3.
Eur Heart J ; 34(30): 2346-53, 2013 Aug.
Article in English | MEDLINE | ID: mdl-23594591

ABSTRACT

AIMS: Lack of gadolinium-contrast wash-in on first-pass perfusion imaging, early gadolinium-enhanced imaging, or late gadolinium-enhanced (LGE) cardiovascular magnetic resonance (CMR) imaging after revascularized ST-elevation myocardial infarction (STEMI) is commonly referred to as microvascular obstruction (MVO). Additionally, T2-weighted imaging allows for the visualization of infarct-related oedema and intramyocardial haemorrhage (IMH) within the infarction. However, the exact histopathological correlate of the contrast-devoid core and its relation to IMH is unknown. METHODS AND RESULTS: In eight Yorkshire swine, the circumflex coronary artery was occluded for 75 min by a balloon catheter. After 7 days, CMR with cine imaging, T2-weighted turbospinecho, and LGE was performed. Cardiovascular magnetic resonance images were compared with histological findings after phosphotungstic acid-haematoxylin and anti-CD31/haematoxylin staining. These findings were compared with CMR findings in 27 consecutive PCI-treated STEMI patients, using the same scanning protocol. In the porcine model, the infarct core contained extensive necrosis and erythrocyte extravasation, without intact vasculature and hence, no MVO. The surrounding-gadolinium-enhanced-area contained granulation tissue, leucocyte infiltration, and necrosis with morphological intact microvessels containing microthrombi, without erythrocyte extravasation. Areas with IMH (median size 1.92 [0.36-5.25] cm(3)) and MVO (median size 2.19 [0.40-4.58] cm(3)) showed close anatomic correlation [intraclass correlation coefficient (ICC) 0.85, r = 0.85, P = 0.03]. Of the 27 STEMI patients, 15 had IMH (median size 6.60 [2.49-9.79] cm(3)) and 16 had MVO (median size 4.31 [1.05-7.57] cm(3)). Again, IMH and MVO showed close anatomic correlation (ICC 0.87, r = 0.93, P < 0.001). CONCLUSION: The contrast-devoid core of revascularized STEMI contains extensive erythrocyte extravasation with microvascular damage. Attenuating the reperfusion-induced haemorrhage may be a novel target in future adjunctive STEMI treatment.


Subject(s)
Cardiomyopathies/pathology , Coronary Occlusion/pathology , Hemorrhage/pathology , Myocardial Infarction/pathology , Adult , Aged , Animals , Balloon Occlusion , Contrast Media , Coronary Thrombosis/pathology , Disease Models, Animal , Female , Humans , Magnetic Resonance Angiography , Magnetic Resonance Imaging, Cine , Male , Meglumine , Microvessels/pathology , Middle Aged , Myocardial Infarction/therapy , Myocardial Revascularization/adverse effects , Necrosis/pathology , Organometallic Compounds , Percutaneous Coronary Intervention , Sus scrofa
4.
Blood ; 116(8): 1360-8, 2010 Aug 26.
Article in English | MEDLINE | ID: mdl-20479286

ABSTRACT

Transfusion-related acute lung injury is suggested to be a "2-hit" event resulting from priming and activation of pulmonary neutrophils. Activation may result from infusion of lysophosphatidylcholines (LysoPCs), which accumulate during storage of blood products. In the present study, we developed a syngeneic in vivo transfusion model to test whether storage of platelet concentrates (PLTs) results in lung injury in healthy rats as well as in a "2-hit" model using lipopolysaccharide-pretreated rats. In addition, the effect of washing of platelets was studied. In healthy rats, transfusion of aged PLTs caused mild lung inflammation. In LPS-pretreated rats, transfusion of aged PLTs, but not fresh PLTs, augmented pulmonary systemic coagulopathy. When PLTs components were transfused separately, supernatant of aged PLTs, but not washed aged platelets, induced pulmonary injury in the "2-hit" model. Supernatants of aged PLTs contained increased concentrations of LysoPCs compared with fresh PLTs, which enhanced neutrophil priming activity in vitro. We conclude that transfusion of aged PLTs induces lung inflammation in healthy rats. In a "2-hit" model, aged PLTs contribute to pulmonary and systemic coagulopathy, which may be mediated by LysoPCs, which accumulate in the supernatant of PLTs during storage.


Subject(s)
Acute Lung Injury/etiology , Blood Coagulation Disorders/etiology , Blood Platelets/metabolism , Disease Models, Animal , Pneumonia/etiology , Transfusion Reaction , Acute Lung Injury/pathology , Animals , Blood Coagulation Disorders/pathology , Blood Platelets/immunology , Blood Platelets/pathology , Chemokines/metabolism , Chromatography, High Pressure Liquid , Cytokines/metabolism , Fibrinolysis , Humans , Immunoenzyme Techniques , Lipopolysaccharides/pharmacology , Lysophosphatidylcholines/pharmacology , Male , Neutrophils/metabolism , Pneumonia/pathology , Rats , Rats, Sprague-Dawley , Specimen Handling , Tandem Mass Spectrometry , Time Factors
5.
Neurology ; 98(7): e759-e768, 2022 02 15.
Article in English | MEDLINE | ID: mdl-34921101

ABSTRACT

BACKGROUND AND OBJECTIVES: Cerebral venous sinus thrombosis (CVST) as a part of the thrombosis and thrombocytopenia syndrome is a rare adverse drug reaction of severe acute respiratory syndrome coronavirus disease 2 (SARS-CoV-2) vaccination. Estimated background rate of CVST with thrombocytopenia is 0.1 per million per month. We assessed the age-stratified risk of CVST with and without thrombocytopenia after SARS-CoV-2 vaccination. METHODS: We estimated the absolute risk of CVST with and without thrombocytopenia within 28 days of a first dose of 4 SARS-CoV-2 vaccinations using data from the European Medicines Agency's EudraVigilance database (until June 13, 2021). As a denominator, we used data on vaccine delivery from 31 European countries. For 22.8 million adults from 25 countries, we estimated the absolute risk of CVST after the first dose of ChAdOx1 nCov-19 per age category. RESULTS: The absolute risk of CVST within 28 days of first-dose vaccination was 7.5 (95% confidence interval [CI] 6.9-8.3), 0.7 (95% CI 0.2-2.4), 0.6 (95% CI 0.5-0.7), and 0.6 (95% CI 0.3-1.1) per million of first doses of ChAdOx1 nCov-19, Ad26.COV2.S, BNT162b2, and mRNA-1273, respectively. The absolute risk of CVST with thrombocytopenia within 28 days of first dose vaccination was 4.4 (95% CI 3.9-4.9), 0.7 (95% CI 0.2-2.4), 0.0 (95% CI 0.0-0.1), and 0.0 (95% CI 0.0-0.2) per million of first doses of ChAdOx1 nCov-19, Ad26.COV2.S, BNT162b2, and mRNA-1273, respectively. In recipients of ChAdOx1 nCov-19, the absolute risk of CVST, both with and without thrombocytopenia, was the highest in the 18- to 24-year-old group (7.3 per million, 95% CI 2.8-18.8 and 3.7 per million, 95% CI 1.0-13.3, respectively). The risk of CVST with thrombocytopenia in ChAdOx1 nCov-19 recipients was the lowest in the age group ≥70 years (0.2, 95% CI 0.0-1.3). Age <60 years compared to ≥60 years was a predictor for CVST with thrombocytopenia (incidence rate ratio 5.79, 95% CI 2.98-11.24, p < 0.001). DISCUSSION: The risk of CVST with thrombocytopenia within 28 days of first-dose vaccination with ChAdOx1 nCov-19 was higher in younger age groups. The risk of CVST with thrombocytopenia was slightly increased in patients receiving Ad26.COV2.S compared with the estimated background risk. The risk of CVST with thrombocytopenia was not increased in recipients of SARS-CoV-2 mRNA vaccines.


Subject(s)
COVID-19 Vaccines , Sinus Thrombosis, Intracranial , 2019-nCoV Vaccine mRNA-1273/adverse effects , Ad26COVS1/adverse effects , Adolescent , Adult , Age Distribution , Aged , BNT162 Vaccine/adverse effects , COVID-19 Vaccines/administration & dosage , COVID-19 Vaccines/adverse effects , ChAdOx1 nCoV-19/adverse effects , Humans , Middle Aged , Risk Assessment , Sinus Thrombosis, Intracranial/epidemiology , Young Adult
6.
PLoS Pathog ; 5(5): e1000447, 2009 May.
Article in English | MEDLINE | ID: mdl-19461880

ABSTRACT

The causative agent of Lyme borreliosis, the spirochete Borrelia burgdorferi, has been shown to induce expression of the urokinase receptor (uPAR); however, the role of uPAR in the immune response against Borrelia has never been investigated. uPAR not only acts as a proteinase receptor, but can also, dependently or independently of ligation to uPA, directly affect leukocyte function. We here demonstrate that uPAR is upregulated on murine and human leukocytes upon exposure to B. burgdorferi both in vitro as well as in vivo. Notably, B. burgdorferi-inoculated C57BL/6 uPAR knock-out mice harbored significantly higher Borrelia numbers compared to WT controls. This was associated with impaired phagocytotic capacity of B. burgdorferi by uPAR knock-out leukocytes in vitro. B. burgdorferi numbers in vivo, and phagocytotic capacity in vitro, were unaltered in uPA, tPA (low fibrinolytic activity) and PAI-1 (high fibrinolytic activity) knock-out mice compared to WT controls. Strikingly, in uPAR knock-out mice partially backcrossed to a B. burgdorferi susceptible C3H/HeN background, higher B. burgdorferi numbers were associated with more severe carditis and increased local TLR2 and IL-1beta mRNA expression. In conclusion, in B. burgdorferi infection, uPAR is required for phagocytosis and adequate eradication of the spirochete from the heart by a mechanism that is independent of binding of uPAR to uPA or its role in the fibrinolytic system.


Subject(s)
Borrelia burgdorferi/immunology , Lyme Disease/immunology , Receptors, Urokinase Plasminogen Activator/metabolism , Animals , Arthritis, Infectious/microbiology , Cell Movement , Heart/microbiology , Histocytochemistry , Humans , Leukocytes/metabolism , Lyme Disease/microbiology , Mice , Mice, Inbred C57BL , Mice, Knockout , Myocarditis/microbiology , Phagocytosis , Receptors, Urokinase Plasminogen Activator/genetics , Skin/metabolism , Skin/microbiology , Statistics, Nonparametric , Up-Regulation , Urinary Bladder/metabolism , Urinary Bladder/microbiology , Urokinase-Type Plasminogen Activator/genetics , Urokinase-Type Plasminogen Activator/metabolism
7.
BMC Geriatr ; 11: 34, 2011 Jul 05.
Article in English | MEDLINE | ID: mdl-21729284

ABSTRACT

BACKGROUND: With an ageing population, older persons become a larger part of the hospital population. The incidence of delirium is high in this group, and experiencing delirium has major short- and long-term sequelae, which makes prevention crucial. During delirium, a disruption of the sleep-wake cycle is frequently observed. Melatonin plays an important role in the regulation of the sleep-wake cycle, so this raised the hypothesis that alterations in the metabolism of melatonin might play an important role in the development of delirium. The aim of this article is to describe the design of a randomised, placebo controlled double-blind trial that is currently in progress and that investigates the effects of melatonin versus placebo on delirium in older, postoperative hip fracture patients. METHODS/DESIGN: Acutely hospitalised patients aged 65 years or older admitted for surgical repair of hip fracture are randomised (n=452) into a treatment or placebo group. Prophylactic treatment consists of orally administered melatonin (3 mg) at 21:00 h on five consecutive days. The primary outcome is the occurrence of delirium, to be diagnosed according to the Confusion Assessment Method, within eight days after start of the study medication. Secondary outcomes are delirium severity, measured by the Delirium Rating Scale; duration of delirium; differences in subtypes of delirium; differences in total length of hospital stay; total dose of antipsychotics and/or benzodiazepine use during delirium; and in-hospital complications. In the twelve-month follow up visit, cognitive function is measured by a Mini-Mental state examination and the Informant Questionnaire on Cognitive Decline in the Elderly. Functional status is assessed with the Katz ADL index score (patient and family version) and grip strength measurement. The outcomes of these assessments are compared to the outcomes that were obtained during admission. DISCUSSION: The proposed study will contribute to our knowledge because studies on the prophylactic treatment of delirium with long term follow up remain scarce. The results may lead to a prophylactic treatment for frail older persons at high risk for delirium that is safe, effective, and easily implementable in daily practice. TRIAL REGISTRATION: Dutch Clinical Trial Registry: NTR1576.


Subject(s)
Delirium/drug therapy , Delirium/psychology , Hip Fractures/drug therapy , Hip Fractures/psychology , Melatonin/therapeutic use , Aged , Delirium/complications , Double-Blind Method , Female , Follow-Up Studies , Hip Fractures/complications , Humans , Male , Placebo Effect , Prospective Studies
8.
JAMA Neurol ; 78(11): 1314-1323, 2021 11 01.
Article in English | MEDLINE | ID: mdl-34581763

ABSTRACT

Importance: Thrombosis with thrombocytopenia syndrome (TTS) has been reported after vaccination with the SARS-CoV-2 vaccines ChAdOx1 nCov-19 (Oxford-AstraZeneca) and Ad26.COV2.S (Janssen/Johnson & Johnson). Objective: To describe the clinical characteristics and outcome of patients with cerebral venous sinus thrombosis (CVST) after SARS-CoV-2 vaccination with and without TTS. Design, Setting, and Participants: This cohort study used data from an international registry of consecutive patients with CVST within 28 days of SARS-CoV-2 vaccination included between March 29 and June 18, 2021, from 81 hospitals in 19 countries. For reference, data from patients with CVST between 2015 and 2018 were derived from an existing international registry. Clinical characteristics and mortality rate were described for adults with (1) CVST in the setting of SARS-CoV-2 vaccine-induced immune thrombotic thrombocytopenia, (2) CVST after SARS-CoV-2 vaccination not fulling criteria for TTS, and (3) CVST unrelated to SARS-CoV-2 vaccination. Exposures: Patients were classified as having TTS if they had new-onset thrombocytopenia without recent exposure to heparin, in accordance with the Brighton Collaboration interim criteria. Main Outcomes and Measures: Clinical characteristics and mortality rate. Results: Of 116 patients with postvaccination CVST, 78 (67.2%) had TTS, of whom 76 had been vaccinated with ChAdOx1 nCov-19; 38 (32.8%) had no indication of TTS. The control group included 207 patients with CVST before the COVID-19 pandemic. A total of 63 of 78 (81%), 30 of 38 (79%), and 145 of 207 (70.0%) patients, respectively, were female, and the mean (SD) age was 45 (14), 55 (20), and 42 (16) years, respectively. Concomitant thromboembolism occurred in 25 of 70 patients (36%) in the TTS group, 2 of 35 (6%) in the no TTS group, and 10 of 206 (4.9%) in the control group, and in-hospital mortality rates were 47% (36 of 76; 95% CI, 37-58), 5% (2 of 37; 95% CI, 1-18), and 3.9% (8 of 207; 95% CI, 2.0-7.4), respectively. The mortality rate was 61% (14 of 23) among patients in the TTS group diagnosed before the condition garnered attention in the scientific community and 42% (22 of 53) among patients diagnosed later. Conclusions and Relevance: In this cohort study of patients with CVST, a distinct clinical profile and high mortality rate was observed in patients meeting criteria for TTS after SARS-CoV-2 vaccination.


Subject(s)
COVID-19 Vaccines/therapeutic use , Drug-Related Side Effects and Adverse Reactions/mortality , Registries , Sinus Thrombosis, Intracranial/mortality , Thrombocytopenia/mortality , Venous Thromboembolism/mortality , Ad26COVS1 , Adult , Aged , BNT162 Vaccine , COVID-19 Vaccines/adverse effects , ChAdOx1 nCoV-19 , Cohort Studies , Female , Hospital Mortality , Humans , Male , Middle Aged , Outcome Assessment, Health Care , Sex Factors , Sinus Thrombosis, Intracranial/blood , Sinus Thrombosis, Intracranial/chemically induced , Syndrome , Thrombocytopenia/blood , Thrombocytopenia/chemically induced , Venous Thromboembolism/blood , Venous Thromboembolism/chemically induced , Young Adult
9.
Crit Care ; 14(2): R65, 2010.
Article in English | MEDLINE | ID: mdl-20398279

ABSTRACT

INTRODUCTION: Influenza accounts for 5 to 10% of community-acquired pneumonias and is a major cause of mortality. Sterile and bacterial lung injuries are associated with procoagulant and inflammatory derangements in the lungs. Activated protein C (APC) is an anticoagulant with anti-inflammatory properties that exert beneficial effects in models of lung injury. We determined the impact of lethal influenza A (H1N1) infection on systemic and pulmonary coagulation and inflammation, and the effect of recombinant mouse (rm-) APC here on. METHODS: Male C57BL/6 mice were intranasally infected with a lethal dose of a mouse adapted influenza A (H1N1) strain. Treatment with rm-APC (125 microg intraperitoneally every eight hours for a maximum of three days) or vehicle was initiated 24 hours after infection. Mice were euthanized 48 or 96 hours after infection, or observed for up to nine days. RESULTS: Lethal H1N1 influenza resulted in systemic and pulmonary activation of coagulation, as reflected by elevated plasma and lung levels of thrombin-antithrombin complexes and fibrin degradation products. These procoagulant changes were accompanied by inhibition of the fibrinolytic response due to enhanced release of plasminogen activator inhibitor type-1. Rm-APC strongly inhibited coagulation activation in both plasma and lungs, and partially reversed the inhibition of fibrinolysis. Rm-APC temporarily reduced pulmonary viral loads, but did not impact on lung inflammation or survival. CONCLUSIONS: Lethal influenza induces procoagulant and antifibrinolytic changes in the lung which can be partially prevented by rm-APC treatment.


Subject(s)
Anticoagulants/antagonists & inhibitors , Anticoagulants/therapeutic use , Blood Coagulation/drug effects , Influenza A Virus, H1N1 Subtype/pathogenicity , Orthomyxoviridae Infections/blood , Protein C/antagonists & inhibitors , Protein C/therapeutic use , Animals , Anticoagulants/metabolism , Down-Regulation/genetics , Influenza A Virus, H1N1 Subtype/genetics , Lung/drug effects , Lung/immunology , Male , Mice , Mice, Inbred C57BL , Models, Animal , Orthomyxoviridae Infections/physiopathology , Protein C/genetics , Protein C/metabolism , Recombinant Proteins , Viral Load
10.
Allergy Asthma Clin Immunol ; 6(1): 22, 2010 Jul 28.
Article in English | MEDLINE | ID: mdl-20667125

ABSTRACT

Hereditary angioedema (C1 inhibitor deficiency, HAE) is associated with intermittent swellings which are disabling and may be fatal. Effective treatments are available and these are most useful when given early in the course of the swelling. The requirement to attend a medical facility for parenteral treatment results in delays. Home therapy offers the possibility of earlier treatment and better symptom control, enabling patients to live more healthy, productive lives. This paper examines the evidence for patient-controlled home treatment of acute attacks ('self or assisted administration') and suggests a framework for patients and physicians interested in participating in home or self-administration programmes. It represents the opinion of the authors who have a wide range of expert experience in the management of HAE.

11.
J Clin Med ; 9(4)2020 Mar 25.
Article in English | MEDLINE | ID: mdl-32218127

ABSTRACT

BACKGROUND: Pulmonary hypercoagulopathy is intrinsic to inhalation trauma. Nebulized heparin could theoretically be beneficial in patients with inhalation injury, but current data are conflicting. We aimed to investigate the safety, feasibility, and effectiveness of nebulized heparin. METHODS: International multicenter, double-blind, placebo-controlled randomized clinical trial in specialized burn care centers. Adult patients with inhalation trauma received nebulizations of unfractionated heparin (25,000 international unit (IU), 5 mL) or placebo (0.9% NaCl, 5 mL) every four hours for 14 days or until extubation. The primary outcome was the number of ventilator-free days at day 28 post-admission. Here, we report on the secondary outcomes related to safety and feasibility. RESULTS: The study was prematurely stopped after inclusion of 13 patients (heparin N = 7, placebo N = 6) due to low recruitment and high costs associated with the trial medication. Therefore, no analyses on effectiveness were performed. In the heparin group, serious respiratory problems occurred due to saturation of the expiratory filter following nebulizations. In total, 129 out of 427 scheduled nebulizations were withheld in the heparin group (in 3 patients) and 45 out of 299 scheduled nebulizations were withheld in the placebo group (in 2 patients). Blood-stained sputum or expected increased bleeding risks were the most frequent reasons to withhold nebulizations. CONCLUSION: In this prematurely stopped trial, we encountered important safety and feasibility issues related to frequent heparin nebulizations in burn patients with inhalation trauma. This should be taken into account when heparin nebulizations are considered in these patients.

12.
J Vasc Interv Radiol ; 20(7): 951-8, 2009 Jul.
Article in English | MEDLINE | ID: mdl-19481472

ABSTRACT

PURPOSE: Arteriovenous (AV) graft thrombosis is a frequent complication in patients undergoing hemodialysis. Thrombolytic therapy with tissue plasminogen activator (TPA) is hampered by the risk of bleeding complications. Locally delivered plasmin may have similar thrombolytic efficacy with a superior safety profile, so herein it was compared with TPA in a porcine model of AV graft thrombosis. MATERIALS AND METHODS: AV grafts were created bilaterally between the carotid artery and jugular vein. Graft thrombosis was induced by clamping the grafts for 1 hour. On day 3, one graft was treated with a 2-mL local recombinant plasmin injection (10 mg; n = 10) with the contralateral graft being infused with TPA (10 mg, n = 8) or saline solution (n = 2). Thrombolytic efficacy was assessed by weighing the residual clot and released clot fragments. RESULTS: After saline solution injection, the mean residual clot weight in the graft was 618 mg. Local administration of TPA showed the least residual clot in the graft (69 mg +/- 26), with large clot particles reaching the venous outflow (241 mg +/- 23). Plasmin treatment significantly reduced the released clot mass versus TPA (52 mg +/- 23; P < .05), whereas residual clot weight was greater compared with TPA treatment (140 mg +/- 22; P < .05). Overall thrombolytic activity of plasmin (ie, residual clot plus released clot) was significantly better than that of TPA (193 mg +/- 25 vs 310 mg +/- 35; P < .05). CONCLUSIONS: The thrombolytic efficacy of recombinant plasmin was shown to be superior to that of TPA in this study.


Subject(s)
Anastomosis, Surgical/adverse effects , Disease Models, Animal , Thrombolytic Therapy/methods , Thrombosis/etiology , Thrombosis/prevention & control , Animals , Fibrinolysin/administration & dosage , Fibrinolysin/genetics , Fibrinolytic Agents/administration & dosage , Humans , Recombinant Proteins/administration & dosage , Swine , Thrombosis/diagnosis , Treatment Outcome
13.
J Aerosol Med Pulm Drug Deliv ; 30(2): 91-99, 2017 Apr.
Article in English | MEDLINE | ID: mdl-27977318

ABSTRACT

BACKGROUND: Critically ill patients are at a constant risk of direct (e.g., by pneumonia) or indirect lung injury (e.g., by sepsis). Excessive alveolar fibrin deposition is a prominent feature of lung injury, undermining pulmonary integrity and function. METHODS: We examined the effect of local administration of recombinant human tissue factor pathway inhibitor (rh-TFPI), a natural anticoagulant, in two well-established models of lung injury in rats. Rats received intratracheal instillation of Pseudomonas aeruginosa, causing direct lung injury, or they received an intravenous injection of Escherichia coli lipopolysaccharide (LPS), causing indirect lung injury. Rats were randomized to local treatment with rh-TFPI or placebo through repeated nebulization. RESULTS: Challenge with P. aeruginosa or LPS was associated with increased coagulation and decreased fibrinolysis in bronchoalveolar lavage fluid (BALF) and plasma. Rh-TFPI levels in BALF increased after nebulization, whereas plasma rh-TFPI levels remained low and systemic TFPI activity was not affected. Nebulization of rh-TFPI attenuated pulmonary and systemic coagulation in both models, without affecting fibrinolysis. Nebulization of rh-TFPI modestly reduced the inflammatory response and bacterial growth of P. aeruginosa in the alveolar compartment. CONCLUSIONS: Local treatment with rh-TFPI does not alter systemic TFPI activity; however, it attenuates both pulmonary and systemic coagulopathy. Furthermore, nebulized rh-TFPI modestly reduces the pulmonary inflammatory response and allows increased bacterial clearance in rats with direct lung injury caused by P. aeruginosa.


Subject(s)
Anti-Inflammatory Agents/pharmacology , Anticoagulants/pharmacology , Lipoproteins/pharmacology , Lung Injury/drug therapy , Animals , Anti-Inflammatory Agents/administration & dosage , Anticoagulants/administration & dosage , Blood Coagulation/drug effects , Bronchoalveolar Lavage Fluid , Disease Models, Animal , Fibrinolysis/drug effects , Humans , Inflammation/drug therapy , Lipopolysaccharides/toxicity , Lipoproteins/administration & dosage , Lung Injury/pathology , Male , Pseudomonas aeruginosa , Random Allocation , Rats , Rats, Sprague-Dawley , Recombinant Proteins
14.
J Hypertens ; 33(3): 627-33, 2015 Mar.
Article in English | MEDLINE | ID: mdl-25426567

ABSTRACT

BACKGROUND: Hyponatraemia is a common, potentially life-threatening, complication of thiazide diuretics. The mechanism of thiazide-induced hyponatraemia is incompletely understood. Previous experiments have suggested a direct effect of thiazide diuretics on the plasma membrane expression of aquaporin (AQP)2. METHODS: We examined the effects of a single re-exposure to hydrochlorothiazide (HCTZ) 50 mg on water balance, renal sodium handling and osmoregulation in 15 elderly hypertensive patients with a history of thiazide-induced hyponatraemia and 15 matched hypertensive controls using thiazide diuretics without previous hyponatraemia. RESULTS: Patients with thiazide-induced hyponatraemia had significantly lower body weight and lower plasma sodium and osmolality at baseline. After HCTZ administration, plasma sodium and osmolality significantly decreased and remained lower in patients compared with controls (P < 0.001). Plasma antidiuretic hormone (ADH) and urine AQP2 were low or suppressed in patients, whereas solute and electrolyte-free water clearance was significantly increased compared with controls. Ad libitum water intake was significantly higher in patients (2543 ±â€Š925 ml) than in controls (1828 ±â€Š624 ml, P < 0.05), whereas urinary sodium excretion did not differ. In contrast, urea excretion remained significantly lower in patients (263 ±â€Š69 mmol per 24 h) compared with controls (333 ±â€Š97 mmol per 24 h, P < 0.05) and predicted the decrease in plasma sodium following HCTZ administration. CONCLUSION: Thiazide diuretics are associated with markedly impaired free water excretion at low ADH and AQP2 in elderly patients. The higher water intake and lower urea excretion in patients points to an important role for polydipsia and urea-mediated water excretion in the pathogenesis of thiazide-induced hyponatraemia.


Subject(s)
Aquaporin 2/urine , Drinking/physiology , Hydrochlorothiazide/administration & dosage , Hyponatremia/metabolism , Sodium Chloride Symporter Inhibitors/adverse effects , Urea/metabolism , Vasopressins/blood , Aged , Aged, 80 and over , Drinking/drug effects , Electrolytes , Female , Humans , Hydrochlorothiazide/therapeutic use , Hypertension/drug therapy , Hypertension/metabolism , Hyponatremia/chemically induced , Kidney/metabolism , Male , Middle Aged , Osmolar Concentration , Sodium/metabolism , Sodium Chloride Symporter Inhibitors/therapeutic use , Water-Electrolyte Balance
15.
PLoS One ; 10(5): e0127261, 2015.
Article in English | MEDLINE | ID: mdl-25992779

ABSTRACT

Pulmonary coagulopathy is intrinsic to pulmonary injury including pneumonia. Anticoagulant strategies could benefit patients with pneumonia, but systemic administration of anticoagulant agents may lead to suboptimal local levels and may cause systemic hemorrhage. We hypothesized nebulization to provide a safer and more effective route for local administration of anticoagulants. Therefore, we aimed to examine feasibility and safety of nebulization of recombinant human tissue factor pathway inhibitor (rh-TFPI) in a well-established rat model of Streptococcus (S.) pneumoniae pneumonia. Thirty minutes before and every 6 hours after intratracheal instillation of S. pneumonia causing pneumonia, rats were subjected to local treatment with rh-TFPI or placebo, and sacrificed after 42 hours. Pneumonia was associated with local as well as systemic activation of coagulation. Nebulization of rh-TFPI resulted in high levels of rh-TFPI in bronchoalveolar lavage fluid, which was accompanied by an attenuation of pulmonary coagulation. Systemic rh-TFPI levels remained undetectable, and systemic TFPI activity and systemic coagulation were not affected. Histopathology revealed no bleeding in the lungs. We conclude that nebulization of rh-TFPI seems feasible and safe; local anticoagulant treatment with rh-TFPI attenuates pulmonary coagulation, while not affecting systemic coagulation in a rat model of S. pneumoniae pneumonia.


Subject(s)
Anticoagulants/administration & dosage , Blood Coagulation/drug effects , Bronchoalveolar Lavage Fluid/chemistry , Lipoproteins/administration & dosage , Pneumonia, Pneumococcal/drug therapy , Administration, Intranasal , Animals , Anticoagulants/adverse effects , Disease Models, Animal , Feasibility Studies , Humans , Lipoproteins/adverse effects , Male , Nebulizers and Vaporizers , Pneumonia, Pneumococcal/blood , Pneumonia, Pneumococcal/microbiology , Rats , Rats, Sprague-Dawley
16.
Int J Hematol ; 76 Suppl 2: 139-44, 2002 Aug.
Article in English | MEDLINE | ID: mdl-12430914

ABSTRACT

Pro-hemostatic therapy aims at an improvement of hemostasis, which may be achieved by amelioration of primary hemostasis, stimulation of fibrin formation or inhibition of fibrinolysis. These treatment strategies may be applied to specifically correct a defect in one of the pathways of coagulation, but have in some situations also been shown to be effective in reducing bleeding in patients without a primary defect in coagulation. Besides the transfusion of platelets in case of thrombocytopenia or severe platelet disorders, a pharmacological improvement of primary hemostasis may be achieved by the administration of desmopressin. The administration of DDAVP results in a marked increase in the plasma concentration of Von Willebrand factor (and associated coagulation factor VIII) and (also by yet unexplained additional mechanisms) a remarkable potentiation of primary hemostasis as a consequence. DDAVP is used for the prevention and treatment of bleeding in patients with von Willebrand disease or mild hemophilia A, and further in patients with an impaired function of primary hemostasis, such as in patients with uremia, liver cirrhosis or in patients with aspirin-associated bleeding. Based on the current insight that activation of coagulation in vivo predominantly proceeds by the tissue factor/factor VII(a) pathway, recombinant factor VIIa has been developed as a prohemostatic agent and has recently become available for clinical use. Indeed, in uncontrolled clinical studies this compound has been shown to exert a potent procoagulant activity and appeared to be highly effective in the prevention and treatment of bleeding, although most experience so far has been obtained in patients with severe and complicated coagulation defects. At present, a more general use of this agent for bleeding patients without an apparent coagulation defect is the subject of a number of ongoing clinical trials. Agents that exert anti-fibrinolytic activity are aprotinin and the group of lysine analogues. The pro-hemostatic effect of these agents proceeds not only by the inhibition of fibrinolysis (thereby shifting the procoagulant/anticoagulant balance towards a more procoagulant state), but also due to a protective effect on platelets, as has been demonstrated at least for aprotinin. The mechanism of this platelet-protective effect has, besides a potential prevention of plasmin-mediated loss of platelet receptors not been elucidated. Whether the pro-hemostatic effect of the anti-fibrinolytic agents will eventually result in a higher incidence of thromboembolic complications is still a matter of debate (see further), however, this has so far not been shown in straightforward clinical trials.


Subject(s)
Hemorrhage/drug therapy , Coagulants/therapeutic use , Disease Management , Hemorrhage/prevention & control , Hemorrhage/therapy , Hemostasis/drug effects , Humans
18.
Trials ; 15: 91, 2014 Mar 25.
Article in English | MEDLINE | ID: mdl-24661817

ABSTRACT

BACKGROUND: Pulmonary coagulopathy is a hallmark of lung injury following inhalation trauma. Locally applied heparin attenuates lung injury in animal models of smoke inhalation. Whether local treatment with heparin benefits patients with inhalation trauma is uncertain. The present trial aims at comparing a strategy using frequent nebulizations of heparin with standard care in intubated and ventilated burn patients with bronchoscopically confirmed inhalation trauma. METHODS: The Randomized Controlled Trial Investigating the Efficacy and Safety of Nebulized HEParin versus Placebo in BURN Patients with Inhalation Trauma (HEPBURN) is an international multi-center, double-blind, placebo-controlled, two-arm study. One hundred and sixteen intubated and ventilated burn patients with confirmed inhalation trauma are randomized to nebulizations of heparin (the nebulized heparin strategy) or nebulizations of normal saline (the control strategy) every four hours for 14 days or until extubation, whichever comes first. The primary endpoint is the number of ventilator-free days, defined as days alive and breathing without assistance during the first 28 days, if the period of unassisted breathing lasts for at least 24 consecutive hours. DISCUSSION: As far as the authors know, HEPBURN is the first randomized, placebo-controlled trial, powered to investigate whether local treatment with heparin shortens duration of ventilation of intubated and ventilated burn patients with inhalation trauma. TRIAL REGISTRATION: NCT01773083 (http://www.clinicaltrials.gov), registered on 16 January 2013.Recruiting. Randomisation commenced on 1 January 2014.


Subject(s)
Anticoagulants/administration & dosage , Heparin/administration & dosage , Lung/drug effects , Nebulizers and Vaporizers , Research Design , Respiration, Artificial , Smoke Inhalation Injury/therapy , Administration, Inhalation , Anticoagulants/adverse effects , Belgium , Clinical Protocols , Double-Blind Method , Heparin/adverse effects , Humans , Intubation, Intratracheal , Lung/pathology , Lung/physiopathology , Netherlands , Recovery of Function , Respiration , Smoke Inhalation Injury/diagnosis , Smoke Inhalation Injury/physiopathology , Time Factors , Treatment Outcome , Ventilator Weaning
19.
Ned Tijdschr Geneeskd ; 156(42): A5515, 2012.
Article in Dutch | MEDLINE | ID: mdl-23075778

ABSTRACT

The 'multimorbidity generalist' is the future. Such doctors will prove to be key to sustainable healthcare systems in the 21st century. The multimorbidity generalist combines preventive, generalist (i.e. system-based), and coaching competencies to treat the increasingly multimorbid patient populations in a patient-centred, effective and efficient way. The medical profession must now dare to take the lead and employ self-regulating policies that will legitimise and strengthen the role of the multimorbidity generalist within in the Dutch healthcare system.


Subject(s)
Chronic Disease/epidemiology , Primary Health Care/trends , Aging/physiology , Comorbidity , Forecasting , Humans , Netherlands , Primary Health Care/methods , Primary Health Care/standards , Quality of Health Care
20.
Ned Tijdschr Geneeskd ; 155: A2306, 2011.
Article in Dutch | MEDLINE | ID: mdl-21291576

ABSTRACT

Severe haemorrhage is a significant cause of death in trauma patients. In the case of massive blood loss a combination of coagulation defects, acidosis and hypothermia arise, which are accompanied by high morbidity and mortality rates unless properly corrected. Research in wounded military showed that a high ratio of fresh frozen plasma to packed red blood cells (FFP:PRBC) seemed to have a positive effect on survival. These studies do not provide a definition of the ideal ratio FFP:PRBC; the ratio in which a positive effect is seen varies from 1:1 to 1:3. Unnecessary FFP transfusions in trauma patients without imminent severe haemorrhage increase the risk of complications such as multi-organ failure and acute respiratory distress syndrome. Additional research is required into the accuracy of diagnosis of acute coagulation disorders.


Subject(s)
Blood Component Transfusion/mortality , Blood Component Transfusion/methods , Hemorrhage/mortality , Hemorrhage/therapy , Hospital Mortality , Blood Coagulation Disorders/mortality , Blood Coagulation Disorders/therapy , Erythrocyte Transfusion , Humans , Injury Severity Score , Multiple Trauma/mortality , Multiple Trauma/therapy , Treatment Outcome
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