PubMed HealthSearch

SEARCH · PubMed Health

Results for “Functional Residual Capacity”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 37 records · Page 2Linked to original sources

[Oscillatory determination of functional residual capacity (FRC)].

The washing-in of a low density gas (80% He, 20% O2) into the lung is being eased by greater diffusibility and diminished work of breathing. Helium analysis was performed by means of the oscillation method with an equipment suitable for the assessment of resistance to breathing. The density of helium gas mixture is being compared to the density of ambient air.

Functional Residual Capacity

Functional residual capacity and body position in the dog.

Resting lung volumes in the supine position (FRCs) were determined by N2 washout method in 67 dogs under pentobarbital anesthesia and computed in ml/kg body weight (BW). In 21 other dogs, FRCs and the change in FRC from the supine to upright positions (deltaFRC) were determined; these lung volumes were expressed in ml/kg BW and in percentage of TLC40 (lung volume at 40 cmH2O positive-pressure inflation). It was found that a) FRCs averaged 38.6 plus or minus 8.2 and 42 plus or minus 5.9 ml/kg BW in the two groups of dogs; b) deltaFRC averaged 23 plus or minus 4 ml/kg BW resulted in large data dispersion, a large coefficient of variation (CV) and a poor correlation (r) of lung volume to BW; D) on the contrary, marked uniformity of FRCs and FRCu (upright FRC) was obtained by expressing the resting lung volumes in %TLC40, allowing an accurate prediction of FRC from the inspiratory capacity (IC). Relationship of FRCu to TLC was comparable to human data reported in the literature. FRCs (%TLC40) was smaller than values previously reported for awake human subjects, probably due to the FRCs reduction in our dogs by anesthesia.

Animals

The effect of artificial ventilation on functional residual capacity and arterial oxygenation. II. Comparison of spontaneous respiration and artificial ventilation at similar arterial carbon dioxide tensions, tidal volumes and inspiratory gas flow rates.

We have compared cardiac output, gas exchange and pulmonary mechanics during spontaneous breathing and artificial ventilaton under conditions which kept PaCO2 within the normal range and maintained constant tidal volume and inspired gas flow rate. In dogs anaesthetized with pentobarbitone and ventilated with air, artificial ventilation increased VD/VT but did not reduce Q angstrom, FRC, or CL. PaO2 increased and A-aDO2 decreased during aritificial ventilation, perhaps because of a small increase in Q angstrom and a small decrease in oxygen consumption. It appears that many of the reported deleterious effects of artificial ventilation may be due to the use of other anaesthetic agents and patterns of ventilation, and to changes in PaCO2.

Anesthesia

Lung volumes and closing capacity with continuous positive airway pressure.

Total lung capacity, vital capacity, residual volume, and functional residual capacity were determined by body plethysmography and the single-breath oxygen (SBO2) test was performed at 0, 5, and 11 cm H20 continuous positive airway pressure in healthy, awake, seated, spontaneously breathing subjects. Mean values for the absolute lung volume at which phase IV of the SBO2 test begins (closing capacity) did not change significantly with continous positive airway pressure at 5 or 11 cm H2O. Mean total lung capacity, functional residual capacity, and residual volume increased significantly, and the mean closing volume, the lung volume above residual volume at which phase IV begins, decreased significantly with 11 cm H20 continuous positive airway pressure; differences at 5 cm H20 were not significant. The slope of the alveolar nitrogen plateau (phase III) obtained during the SBO-2 test did not change with continuous positive airway pressure.

Adult

Lung volumes in scoliosis before and after correction by the Harrington instrumentation method.

Studies of static lung volumes were performed before and after surgery in 92 scoliotic patients, aged 10 to 25 years. The majority of the patients had idiopathic dorsal curves. Vital capacity, total lung capacity, functional residual capacity and residual volume were measured at least 18 months after surgery. A significant increase was observed in all static volumes, averaging 10 per cent; the pre- and postoperative values were expressed in per cent of predicted normal values according to age and height. Correction of body height was taken into consideration in the prediction of normal values. Patients with the more advanced scoliosis had the greatest improvement in lung volumes. The patients were treated postoperatively with a Milwaukee brace for an average of 15 months. The use of this brace, which allows for chest expansions, might account for the improved lung function compared to previous series where plaster body jackets were used. Thus the correction of idiopathic scoliosis by the standard posterior fusion with Harrinton instrumentation together with our postoperative routine provides a lasting reduction of the spinal deformity, prevents progression of respiratory impairment and, in fact, increases the lung volumes, vital capacity, total lung capacity and functional residual capacity by an average of 10 per cent.

Adolescent

Lung function in children with recurrent bronchitis.

Lung function was studied in 29 children suffering from recurrent bronchitis (average number of bronchitis attacks per year: 4.2 +/- 0.5). Most of them (73%) were 1--7 years old. The date of exploration in relation to the last acute bronchitis was on average 6 weeks. Lung mechanics, residual functional capacity, blood gases and regional lung function were measured. Most of the children were suffering from some kind of functional disorder; alteration of lung mechanics -- increase of lung resistance (22/29) decrease of dynamic compliance (15/23); increase of functional residual capacity (6/10), non specific bronchial hypersensitivity (12/17); regional ventilatory and perfusion malfunction. These functional disorders could be the first evidence of the bronchial lesions which cause chronic obstructive bronchitis in adults.

Bronchitis