Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0034067 (emphysema)
 11,506 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The effects of variations in the volume conductor properties of the torso on the electrocardiogram were studied by means of a theoretical eccentric spheres model. The model includes a blood cavity, cardiac muscle layer, pericardium, lung region, skeletal muscle layer, and subcutaneous fat. The source of the field is a double-layer spherical cap located within the myocardium. The following effects regarding the electrocardiogram (ECG) potentials were determined: (1) blood augments the potential, but less than predicted by simpler published models; (2) in anemia, high potentials are expected, whereas in polycythemia, voltages are reduced; (3) abnormally low lung conductivity (emphysema) causes low surface potentials whose magnitude is controlled by the low conductivity skeletal muscle layer; (4) low voltages result both from low and high pericardial conductivities; (5) the surface potential increases with increasing myocardial conductivity; (6) low skeletal muscle conductivity (Pompe's disease) causes high surface potentials; (7) obesity lowers the potential only slightly; (8) a thick myocardium, protruding into the lung region, slightly augments the potential; (9) an increase in the thickness of the myocardium at the expense of the blood cavity causes a decrease in potential; (10) the potential increases with increasing heart size; and (11) the location of the heart within the torso has a very significant effect on the surface potential distribution.
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PMID:The effects of variations in conductivity and geometrical parameters on the electrocardiogram, using an eccentric spheres model. 75 26

We report a case of subcutaneous and mediastinal emphysema in a 39-year-old woman with late-onset Pompe disease who was undergoing non-invasive positive pressure ventilation (NPPV). Although the patient had a history of pneumothorax, she did not present with pneumothorax at the time of admission. She had not undergone adequate respiratory rehabilitation, which resulted in decreased respiratory compliance. We speculated that the emphysema had been caused by an increase in the airway pressure due to NPPV. Decrease in inspiratory pressure of NPPV from 14 cm H2O to 9 cm H2O made the patient dyspneic and hypoxic. Cuirass ventilation by itself resulted in dyspnea and hypoxia. By using a combination of cuirass ventilation (control mode) and NPPV (assist/control mode), we were able to decrease the inspiratory pressure to 7 cm H2O. After 26 days of treatment, the patient recovered from subcutaneous and mediastinal emphysema. After the treatment, her maximum inspiratory capacity was increased from 400 ml to 600 ml, which indicates increased thoracic compliance. Thus, a combination of cuirass ventilation and NPPV is beneficial in managing barotrauma that may occur during NPPV in a respirator-dependent patient.
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PMID:[Treatment of subcutaneous and mediastinal emphysema with cuirass ventilation in a patient with Pompe disease undergoing non-invasive positive pressure ventilation]. 2053 78