119 research outputs found
Does phase 2 of the expiratory PCO2 versus volume curve have diagnostic value in emphysema patients?
It has been postulated that serial inhomogeneity of ventilation in the
peripheral airways in emphysema is represented by the shape of expiratory
carbon dioxide tension versus volume curve. We examined the diagnostic
value of this test in patients with various degrees of emphysema. The
volumes between 25-50% (V25-50) and 25-75% (V25-75) of the expiratory
carbon dioxide tension versus volume curve were determined in 29
emphysematous patients (20 severely obstructed and 9 moderately
obstructed), 12 asthma patients in exacerbation of symptoms, and 28
healthy controls. Discriminant analysis was used to examine whether these
diagnostic groups could be separated. With regard to phase 2 of the
expiratory CO2 versus volume curve (mixture of anatomic deadspace and
alveolar air), a plot of intercept versus slope of the relationships of
(V25-50) and (V25-75) versus inspiratory volume (VI) from functional
residual capacity (FRC), obtained during natural breathing frequency,
proved to be most discriminating in the separation between healthy
controls and severely obstructed emphysema patients. Separating healthy
controls and severely obstructed emphysema patients on the basis of the
discriminant line for V25-50, 9 of the 12 asthma patients in exacerbation
were classified as normal, and only 5 of the 9 moderately obstructed
emphysema patients as emphysematous. For V25-75 involvement of phase 3 of
the curve (alveolar plateau) in asthma patients in exacerbation caused a
marked overlap with the severely obstructed emphysema patients. In the
healthy controls, a fixed breathing frequency of 20 breaths.min-1 led to
an increase of both volumes.(ABSTRACT TRUNCATED AT 250 WORDS
Pulmonary hypertension after transjugular intrahepatic portosystemic shunt (TIPS)
We reported the case of a patient in whom severe, and ultimately fatal,
pulmonary hypertension developed 1.5 yrs after transjugular intrahepatic
portosystemic shunt (TIPS). Pulmonary artery pressures were not affected
by 100% oxygen, prostacyclin or nifedipine. Postmortem examinations showed
pulmonary and vascular abnormalities typical of pulmonary hypertension.
Pulmonary artery pressures should be measured in each patient with
otherwise not readily explained dyspnoea following transjugular
intrahepatic portosystemic shunt
The Cloning and Expression of Human Monoclonal Antibodies: Implications for Allergen Immunotherapy
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