Biomedical subjects

Tore Amundsen

Publications and source records attributed to Tore Amundsen.

4 recordsLinked to original sources

PubMed2006

Heparin resistance and increased platelet activation in coronary surgery patients treated with enoxaparin preoperatively.

OBJECTIVE: Patients with unstable coronary disease have changes in the hemostatic system. These patients are often treated with low molecular weight heparin. In patients who are accepted for coronary artery bypass grafting, treatment with low molecular weight heparin is frequently continued until surgery. We hypothesized that in coronary artery bypass grafting, the hypercoagulable state seen in unstable patients persists into the intra- and postoperative phase despite preoperative treatment with low molecular weight heparin. The aim of this study was to explore and describe the perioperative hemostatic process in patients with unstable coronary artery disease undergoing coronary artery bypass grafting. METHODS: Thirty-two patients with unstable coronary disease treated preoperatively with enoxaparin, and 32 stable control patients not treated with enoxaparin, were included. All patients were taking low dose aspirin until the day before surgery. Before cardiopulmonary bypass, all patients were given tranexamic acid as a bolus injection. Blood samples for analysis of platelet counts, international normalized ratio, activated partial thromboplastin time, fibrinogen, protein S, protein C, prothrombin fragment 1 + 2, thrombin-antithrombin complex, antithrombin, plasmin-antiplasmin complex, D-dimer, neutrophil-activating peptide 2, platelet-monocyte complexes, and heparin concentrations were drawn preoperatively, after 30 min on cardiopulmonary bypass, and 30 min, 3 h, and 20 h postoperatively. Heparin was given during cardiopulmonary bypass to maintain an activated clotting time above 480 s. RESULTS: Patients in the enoxaparin group needed more heparin to maintain an activated clotting time above 480 s, and had higher heparin concentrations and lower antithrombin values compared with control patients. Neutrophil-activating peptide 2 concentrations were higher in the enoxaparin group. CONCLUSIONS: Patients treated with enoxaparin before coronary artery bypass grafting showed signs of heparin resistance intraoperatively. Enoxaparin-treated patients also had increased perioperative platelet activation. Reasons for the observed difference in platelet activation remain unclear.

Aged↗

PubMed2002

[Lead poisoning--a case report].

Lead poisoning may cause irreversible health defects, including anaemia, central nervous system problems and various organ defects. We describe a patient with lead poisoning. A 54-year-old woman was admitted to hospital with anaemia and unspecific gastrointestinal symptoms. Peripheral blood smear and bone marrow aspirate showed basophilic stippling of erythrocytes suggestive of lead poisoning, which was confirmed by high concentrations of lead in her blood. The lead source was the glazing of a ceramic wine jug. Chelating therapy was started. Haemoglobin was normalised; the patient returned to work after nine months. Correct diagnosis and treatment can prevent serious health problems caused by lead poisoning.

Bone Marrow Examination↗

PubMed2002

[Lead poisoning--an overview].

MATERIAL AND METHODS: We present a review of the history, pathophysiology, diagnosis and treatment of lead poisoning based on relevant literature. RESULTS AND INTERPRETATION: The human body does not metabolize lead, and lead accumulation may cause organ failure. Lead poisoning may cause serious health defects, including anaemia, central nervous system problems and various organ defects. Sources of lead may be found in the home as well as in the workplace or elsewhere in our environment, but lead poisoning is an infrequent condition. Prevention is important, but manifest lead poisoning can be treated effectively.

Acute Disease↗

PubMed2002

Perfusion abnormalities in pulmonary embolism studied with perfusion MRI and ventilation-perfusion scintigraphy: an intra-modality and inter-modality agreement study.

PURPOSE: To compare perfusion magnetic resonance imaging (MRI) and ventilation-perfusion scintigraphy (V-P scan) in the study of perfusion abnormalities in pulmonary embolism (PE) and to compare the PE results to the findings previously reported for pneumonia and chronic obstructive pulmonary disease (COPD), in terms of perfusion abnormalities. MATERIALS AND METHODS: Dynamic contrast-enhanced MR images and V-P scans of 20 patients with PE, 11 patients with acute pneumonia, and 13 patients with exacerbation of COPD were studied. Five categories of perfusion abnormalities within each imaging modality were defined. Intra- and inter-modality agreement (kappa values) in the evaluation of perfusion abnormalities were calculated, based on the two observers of each imaging modality (all blinded to each other and true diagnosis). Finally, three categories of perfusion MRI diagnosis (PE, pneumonia, and COPD) were also defined and the inter-observer agreement (kappa value) was calculated. RESULTS: For PE, the intra-modality agreement (kappa value) in the evaluation of perfusion abnormalities was 0.77 for MRI and 0.65 for V-P scan. The inter-modality agreement varied from 0.52 to 0.57, respectively, and was observer-dependent. For the pooled group of PE, pneumonia, and COPD, the intra-modality agreement of perfusion abnormalities was 0.76 for MRI and 0.65 for V-P scan, and the inter-modality agreement varied from 0.51 to 0.56. The kappa value for inter-observer agreement for MRI diagnosis was 0.92. CONCLUSION: Evaluation of perfusion abnormalities in PE, pneumonia, and COPD using perfusion MRI and V-P scan showed a high intra-modality agreement that was higher than the inter-modality agreement. Further studies are now needed in patients presenting with possible PE to evaluate the sensitivity and specificity of the method.

Acute Disease↗