PubMed Health⌕ Search

Biomedical subjects

F Ruff

Publications and source records attributed to F Ruff.

At least 55 records · Page 3Linked to original sources
PubMed1975

[Determination of the closing volume and its value in the early detection of chronic obstructive lung disease].

The determination of the closing volume appears as a good test for the early detection of obstructive lung diseases and of disorders in the ventilation distribution. Easy to perform, its use should become extensive. To make use of this investigation under the better possible conditions, it is strictly necessary to respect methodologic norms and an excellent technology and to be aware of some morphologic anomalies in the curves.

Age Factors↗
PubMed1975

[Continuous measurement, using 2 isotopes, of extravascular pulmonary water. Application of a new method or the analysis of supply and pulmonary capillary filtration in normal man].

Measurement of pulmonary interstitial fluid may be useful in clinical medicine for early diagnosis or measurement of interstitial and/or alveolar pulmonary edema. A modification of the double dilution method of CHINARD and GORESKY is proposed. Compared to previous methods, this technique, using two isotopes gamma emitters, is rapid, simple, reproductible and may be repeated. The values obtained in normal subjects at rest 3.5 +/- 0.5 ml/kg, are comparable with those of other authors. They increase considerably in cases of fluid load.

Body Water↗
PubMed1975

[Regional distribution of pulmonary perfusion during fluid overload in man].

The effects of a fluid vascular overload (Dextran 40,000, 10 p. 100, 44 +/- ml/kg/45 min) were studied in 9 normal subjects in the upright position. The following were found: an increase in pulmonary blood volume (+30 p. 100), and in extravascular pulmonary water (+ 70 p. 100), a significant fall in pulmonary compliance and an increase in bronchial resistance. Radio-isotopic study of the regional distribution of pulmonary perfusion showed a clear inversion with decrease in perfusion at the bases and increase at the apices. From the theoretical standpoint, this inversion of distribution of perfusion can be due to hypoxic vasoconstriction in the lung bases, to an increase in flow and entry pressures recruiting apical vessels or to a perivascular compressive edema in the lower parts of the lungs. Different modifications complementing the initial experimental protocol tend to prove that it is this latter reason which is essentially at the origin of the inversion in regional distribution of pulmonary perfusion.

Adult↗
PubMed1974

Effects of age and posture on closing volume.

Closing volume and closing capacity increased linearly with age. In the seated position, the closing volume exceeded the expiratory reserve volume in subjects older than about 65 years, while in the supine position, as the expiratory reserve volume is markedly reduced, this occurred at about 44 years. Above these two "critical ages", ventilation to the dependent parts of the lungs is reduced during the normal tidal volume breathing. Thus, in seated subjects older than 65 years and in supine individuals older than 44 years there is significant impairment of ventilation distribution to the dependent lung zones, which necessiarly causes impaired gas exchange within the lungs.

Adolescent↗
PubMed1971

Regional lung function in patients with hepatic cirrhosis.

The lung volume at which the dependent lung zones begin to trap gas as a result of airway closure (i.e., the "closing volume") was measured with (133)Xe in 10 seated patients with hepatic cirrhosis. In all of them the closing volume was increased above normal, and in eight it was greater than the functional residual capacity, indicating the presence of airway closure and gas trapping during resting tidal volume breathing. Direct measurements made with (133)Xe in five cirrhotic patients (a) confirmed the presence of increased gas trapping in the lower lung zones both at residual volume and at functional residual capacity, and (b) indicated that in liver cirrhosis the ventilation-perfusion ratio of the dependent lung zones may be very low, primarily as a result of decreased ventilation due to airway closure. It is concluded that in hepatic cirrhosis, gas trapping in the dependent lung zones may be an important cause of impaired gas exchange within the lungs. It is suggested that the premature airway closure observed in this disease may be due to mechanical compression of small airways by dilated blood vessels and/or interstitial pulmonary edema.

Adolescent↗