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J van der Meer

Publications and source records attributed to J van der Meer.

14 recordsLinked to original sources

Logistical problems in prehospital thrombolysis.

In this study we compared efficacy and safety of prehospital with in-hospital thrombolytic treatment with anistreplase in patients with acute myocardial infarction (AMI). Three-hundred and fifty patients with chest pain were screened for eligibility by the municipal ambulance staff and/or the general practitioner. Patients were included in the absence of contraindications and if the telephone-transmitted ECG showed AMI. In a 6 month period 16 patients (5%) were eligible, but only seven (2%) were randomized. Age over 70 years, duration of chest pain for longer than 4 h and logistic problems were the major factors responsible for the low inclusion rate. The mean time spent at home with and without the ECG procedure was 38 +/- 14 and 14 +/- 8 min, respectively (P less than 0.001). These results demonstrate that in a medium sized town prehospital delivery of intravenous thrombolytic therapy by paramedics and/or the general practitioner is not feasible, leads to unnecessary time delay and may therefore yield no clinical benefits.

Adult

Complement activation and the production of inflammatory mediators during the treatment of severe sepsis in humans.

Sepsis or septic shock is frequently associated with activation of the complement system, coagulation and fibrinolytic changes and the release of several cytokines. In this study we analyzed the relation of complement activation to the inflammatory mediators, hemodynamic and biochemical parameters and severity of illness and outcome in 20 consecutive patients with clinically defined sepsis. Levels of C3a and C3d were elevated in 90% of the patients (median levels 0.19 mg/l and 8.6 mg/l respectively) in comparison to 14% and 42%, respectively of 7 patients with non-septic shock. Levels of C4 were decreased in only 1 of the 20 septic patients. Levels of TNF and IL-6 were elevated in 94% and 100% of the patients, Levels of TNF and IL-6 were elevated in 94% and 100% of the patients, respectively (median levels 122 ng/l and 1300 U/ml) and were clearly interrelated (r = 0.67, p less than 0.01). C3a levels correlated with the APACHE II score (r = 0.57, p less than 0.05) and high C3a levels were associated with fatal outcome (p less than 0.05). C3a was also correlated inversely with mean arterial pressure (r = 0.50, p less than 0.01). Levels of complement C3a and C3d significantly correlated with levels of plasminogen activator inhibitor-1 (PAI) and correlated inversely with AT-III levels. We found no correlation between these complement products and leukocyte counts or lactate levels, nor was there a correlation between C3a or C3d and the cytokines TNF and IL-6. Levels of C3a and C3d did not decrease significantly during the first 24 h of treatment, in contrast to a clear decrease in IL-6 levels in all patients and a decrease in TNF in the surviving patients. TNF levels remained stable or increased in the non-survivors. We conclude that both the complement system and the cytokine system are involved in the pathogenesis of septic shock and may be involved in the development of some of the fatal complications like hypotension and disseminated intravascular coagulation.

Aged

Rheological properties of blood in Raynaud's phenomenon.

Rheological tests were performed in four rigorously defined groups of patients with Raynaud's phenomenon: primary family-related (n = 21), primary family-unrelated (n = 30), 'possible scleroderma' (n = 26), and scleroderma (n = 19). Whole blood and plasma viscosity, and hematocrit were significantly higher in the 'possible scleroderma' group. We conclude that the contribution of central rheological abnormalities in the pathogenesis of Raynaud's phenomenon is limited.

Blood Viscosity

Vascular proliferation as an unusual cause of hemorrhagic diathesis in myelofibrosis.

One year after splenectomy, a patient with myelofibrosis developed spontaneously large hematomas that were not due to coagulation abnormalities or functionally defective platelets. At autopsy, the liver, muscle, and skin showed extramedullary hematopoiesis associated with capillary proliferation and extravasation of blood. These findings indicate that neovascularization can be an additional cause of bleeding in myeloproliferative disorders and might be induced by neoplastic hematopoietic cells.

Aged