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Results for “Functional Residual Capacity”

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PubMed1986

Effect of short and long term antibiotic response on lung function in bronchiectasis.

In a study designed to show whether purulent bronchial secretions damage the lung reversibly or irreversibly, 18 patients with bronchiectasis underwent lung function tests before and after two weeks' antibiotic treatment to convert their sputum from purulent to mucoid, and 10 of them also after four months' treatment. After two weeks FEV1, forced vital capacity, vital capacity, functional residual capacity, and total lung capacity showed small but statistically significant (though not clinically useful) improvements. In the 10 patients studied after four months only FVC (of the four indices with significant improvements at two weeks in this group) was still higher than before treatment. These results contrast with those of an earlier study, in which large acute changes were found, perhaps because of differences in the patients studied. It is concluded that the absence of major changes in lung function points to physiological abnormality that is largely irreversible in these patients with chronic bronchial sepsis.

Adult↗

PubMed1979

Serum factor in cystic fibrosis: correlation with clinical parameters.

The relationship between the activity of the cystic fibrosis serum ciliary dyskinesia factor, detected by the rabbit tracheal bioassay, and clinical status of the patient has been investigated in children, 1-24 years old, with cystic fibrosis. No significant correlation was found between the amount of serum factor activity and age, clinical status assessed by the Schwachman score, pulmonary function (vital capacity, functional residual capacity, total lung capacity, residual volume, maximum breathing capacity, maximal midinspiratory flow, and maximal midexpiratory flow) or blood gas levels (pCO2, pO2). The activity showed no significant relationship to serum galactosyltransferase activity in children with cystic fibrosis.

Adolescent↗

PubMed1997

Therapeutic effects of diuretics and paracentesis on lung function in patients with non-alcoholic cirrhosis and tense ascites.

BACKGROUND/AIMS: Ascites may cause or aggravate pulmonary dysfunction in patients with liver cirrhosis. Diuretics and paracentesis are the main therapies for ascites. The aim of the present study was to evaluate and compare the therapeutic effects of diuretics and large-volume paracentesis on lung function in 26 male patients with non-alcoholic cirrhosis and tense ascites. METHODS: The patients were divided into two groups. Group A was composed of 13 subjects who were treated with diuretics including spironolactone (100-400 mg/day) and furosemide (80-320 mg/day). In group B, 13 subjects received large-volume paracentesis plus intravenous albumin (6-8 g/l ascites removed). Pulmonary function tests including spirometry, plethysmography, single-breath carbon-monoxide diffusing capacity (DLco) and arterial blood gases, were done 1 day before diuretic treatment and 1 day after termination of the study in group A patients, and 1 day before and after large-volume paracentesis in group B subjects. RESULTS: Before treatment, the clinical and laboratory data were comparable between the two groups. After treatment, ventilatory function as evidenced by forced expiratory volume in 1 s, forced vital capacity, total lung capacity, functional residual capacity and expiratory reserve volume, and DLco increased significantly in both groups. Arterial PO2 and PCO2 increased significantly and AaPO2 (alveolar-arterial PO2 difference) decreased significantly in the subjects treated with diuretics. Nevertheless, paracentesis did not improve arterial blood gases. The changes in lung volumes, DLco and PaO2 after treatment (the data after minus those before treatment) were comparable, except that a significant decrease in AaPO2 was observed in the diuretic group. CONCLUSIONS: Both diuretic therapy and large-volume paracentesis significantly improved the ventilatory function in patients with tense cirrhotic ascites. In terms of oxygenation improvement as evaluated by AaPO2, diuretic treatment may be superior to large-volume paracentesis.

Aged↗

PubMed1991

Influence of excessive weight loss on respiratory function. A study of obese patients following gastroplasty.

The influence of excessive weight loss, with decreased muscle mass, on pulmonary function was evaluated in 16 obese patients without clinical evidence of respiratory disease. Weight loss was induced with vertical banded gastroplasty. Six nonobese age-matched patients undergoing elective cholecystectomy acted as controls. Preoperative values for static and dynamic lung function variables and for pulmonary gas distribution and respiratory muscle strength were compared with postoperative values after approximately 10% and 18% weight reduction. Before gastroplasty the dominant abnormality of respiratory function was slight restrictiveness, with reduced lung volumes. Body weight and lean body mass decreased significantly during the study period, and respiratory muscle strength was significantly reduced after 10% weight loss. Lung function tests nevertheless showed significant increase of vital capacity, functional residual capacity, total lung capacity and maximal voluntary ventilation. No correlation was found between the reduction of respiratory muscle strength and that of lean body mass. The controls did not diminish the body weight after surgery and the lung volumes and respiratory muscle strength was not changed.

Adult↗

PubMed1996

Postoperative pulmonary function after laparoscopic and open cholecystectomy.

In this prospective, randomized study, we compared 42 patients undergoing laparoscopic cholecystectomy and 40 undergoing open cholecystectomy to determine if laparoscopic cholecystectomy results in less respiratory impairment and fewer respiratory complications. Pulmonary function tests, arterial blood-gas analysis and chest radiographs were obtained in both groups before operation and on the second day after operation. Postoperative pain scores and analgesic requirements were also recorded. After operation, a significant reduction in total lung capacity, functional residual capacity (FRC), forced expiratory volume in 1 s (FEV1), forced vital capacity (FVC) and mid-expiratory flow (FEF25-75%) occurred after both laparoscopic and open cholecystectomy. The reductions in FRC, FEV1, FVC and FEF25-75% were smaller after laparoscopic (7%, 22%, 19% and 23%, respectively) than after open (21%, 38%, 32% and 34%, respectively) cholecystectomy. Laparoscopic cholecystectomy was also associated with a significantly lower incidence (28.6% vs 62.5%) and less severe atelectasis, better oxygenation and reduced postoperative pain and analgesia use compared with open cholecystectomy. We conclude that postoperative pulmonary function was impaired less after laparoscopic than after open cholecystectomy.

Adult↗

PubMed2002

Postoperative pulmonary function in coronary artery bypass graft surgery patients undergoing early tracheal extubation: a comparison between short-term mechanical ventilation and early extubation.

OBJECTIVE: To evaluate the effect of a short period of mechanical ventilation (3 hours) versus immediate extubation (within 1 hour of surgery) on pulmonary function, gas exchange, and pulmonary complications after coronary artery bypass graft (CABG) surgery. DESIGN: Prospective randomized study. SETTING: University teaching hospital. PARTICIPANTS: Thirty-five patients undergoing CABG surgery. INTERVENTIONS: Patients were randomized into 2 groups. Patients in group I were extubated as soon as possible after surgery. Patients in group II were ventilated for a minimum of 3 hours after surgery. Patients in both groups were extubated only after achieving predetermined extubation criteria. Patients who did not meet the criteria for extubation within the predetermined set time limit (90 minutes in group I and 6 hours in group II) were withdrawn from the study. Pulmonary function tests (vital capacity, forced expiratory volume in 1 second, total lung capacity, functional residual capacity), arterial blood gases, and chest radiographs were done preoperatively and postoperatively. Pulmonary complications were recorded. MEASUREMENTS AND MAIN RESULTS: Demographic data were similar between groups. The mean time to extubation in group I was 45.7 plus minus 27.6 minutes and in group II was 201.4 plus minus 21 minutes (p < 0.01). Two patients in group I and 1 patient in group II did not meet the extubation criteria within the predetermined set time limit and were excluded from the study. In both groups, there was a significant decline in pulmonary function but no differences between groups at 24 or 72 hours after surgery. There were no differences between groups in blood gases, atelectasis scores, or pulmonary complications. CONCLUSION: The data suggest that extending mechanical ventilation after CABG surgery does not affect pulmonary function. Provided that routine extubation criteria are met, patients can be safely extubated early (within 1 hour) after major cardiac surgery without concerns of further pulmonary derangement.

Anesthesia Recovery Period↗

PubMed1994

Effect of large-volume paracentesis on pulmonary function in patients with cirrhosis and tense ascites.

The effect of large-volume paracentesis on lung function was evaluated in 12 male patients with cirrhosis. All underwent pulmonary function tests including spirometry, plethysmography and single-breath carbon-monoxide diffusing capacity 1 day before and after paracentesis. The amount of ascitic fluid removed ranged from 3.6 to 131 (mean +/- SD, 7.4 +/- 3.01). After paracentesis, forced vital capacity, forced expiratory volume at 1 s, total lung capacity, functional residual capacity, inspiratory capacity, expiratory reserve volume, diffusing capacity and alveolar volume increased significantly. In contrast, Kco (diffusing capacity corrected by alveolar volume) decreased significantly. After paracentesis, the increase in diffusing capacity was highly correlated with lung volumes and the amount of removed ascitic fluid. Nevertheless, a significantly negative correlation was found between the change of Kco before and after paracentesis and that of lung volumes. The increase in lung volumes and ventilation to the lower lungs with unfavorable ventilation-perfusion matching might explain the discrepancy between changes in diffusing capacity and Kco after large-volume paracentesis. In conclusion, these results suggest that pulmonary function in patients with cirrhosis and tense ascites is partly improved by large-volume paracentesis. Large-volume paracentesis might be useful for symptomatic relief in selected patients with tense ascites.

Ascites↗

PubMed1985

Phrenic and diaphragm function after coronary artery bypass grafting.

We studied respiratory mechanics and phrenic nerve and diaphragm function in 12 patients on the day before and eight to 13 days after coronary artery bypass grafting. The average vital capacity, functional residual capacity, and total lung capacity decreased by 20.5%, 9.5%, and 14.7% respectively after operation. Eleven patients showed less negative maximum inspiratory mouth pressures at any given lung volume after surgery and the magnitude of the change correlated with the reduction in total lung capacity. In 11 of the 12 patients the conduction times of the right and left phrenic nerves did not change substantially after operation and the ratio of inspiratory electrical activity (Edi) of left and right hemidiaphragms was similar before and after the procedure. One patient, however, showed a considerable increase in left phrenic nerve conduction time and a reduction in the left to right Edi ratio postoperatively. In three patients diaphragm function was also assessed by changes in transdiaphragmatic pressure during supramaximal phrenic nerve stimulation and voluntary increase in inspired volume; in none of the three patients did the transdiaphragmatic pressure swings show any significant change in the postoperative period. These data indicate that phrenic nerve paralysis only occasionally accounts for the postoperative loss of lung volume after coronary artery bypass grafting surgery. The mechanism of these abnormalities therefore remains to be determined.

Coronary Artery Bypass↗

PubMed1997

Respiratory status and allergy nine to 10 years after acute bronchiolitis.

In order to evaluate further the relationship between acute bronchiolitis in infancy and subsequent respiratory problems, children prospectively followed up from the time of their admission to hospital were reviewed along with a group of matched controls recruited at the previous five and a half year assessment. Sixty one index children and 47 controls took part. The groups were well matched for age, height, parental smoking, and social class. Although the prevalence of respiratory symptoms had fallen when related to the previous review, there remained an excess of coughing (48 and 17% in index and control children respectively; odds ratio 4.02) and wheezing (34 and 13% in index and control children respectively; odds ratio 3.59). Bronchodilator therapy was used by 33% of index children compared with 3% of controls. Lung function tests revealed no significant differences in the measurements of lung growth-for example, forced vital capacity, functional residual capacity, and total lung capacity-but the index children had significant reductions in measurements of airways obstruction-for example, forced expiratory volume in one second, maximum expiratory flow at 75, 50 and 25% of vital capacity, and airways resistance. Family history and personal skin tests showed no excess of atopy in the index group. This study supports the claim that the excess respiratory symptoms after acute bronchiolitis are not due to familial or personal susceptibility to atopy.

Acute Disease↗

PubMed1978

Pulmonary artery pressure in thoracic scoliosis during and after exercise while breathing air and pure oxygen.

Pulmonary artery catheterisation was carried out in 25 scoliotics aged 13 to 67 years (mean 30.7). Each then performed a progressive exercise test breathing air, and 11 performed a similar test breathing pure oxygen. The mean pulmonary artery pressure (PAP) increased linearly with oxygen uptake (VO2) and with the work rate. The pressure responses have been described in terms of ther intercept and rate of rise of pressure (sPAP/VO2 and sPAP/work rate). sPAP/VO2 was unrelated to the anatomical features of the scoliosis, or to PaO2. It was inversely related to vital capacity, functional residual capacity, and total lung capacity. Inspiration of pure oxygen lowered the resting pressure by a mean of 3.2 mmHg but only decreased sPAP/work rate by 9%. The maximum pressure reached during exercise was diminished by a mean of 5.2 mmHg when pure oxygen was breathed. The mean pressures were shown to fall exponentially after exercise. The time constants were proportional to sPAP/VO2 and to the final pressure reached during exercise. Inspiration of pure oxygen did not effect the time constants but decreased the post-exercise pressure load by lowering the final pressure during exercise.

Adolescent↗

PubMed1987

Effect of ozone exposure on lung functions and plasma prostaglandin and thromboxane concentrations in guinea pigs.

Male Hartley guinea pigs were exposed either to filtered air or to 1 ppm ozone (O3) for 1 hr. At 2, 8, 24, or 48 hr after exposure we measured ventilation, respiratory mechanics, lung volumes, diffusing capacity for carbon monoxide (DLCO), and alveolar volume (VA) in anesthetized, tracheotomized animals. Respiratory frequency and tidal volume were unchanged in all groups. Pulmonary resistance was increased 2 hr after O3 but returned to control at 8 hr and thereafter. Prolonged reductions in lung volumes (total lung capacity, vital capacity, functional residual capacity, and residual volume) as well as in DLCO and VA occurred after O3, with maximum decreases at 8 and 24 hr postexposure. Increased ratios of wet lung weight to body weight were seen at 2, 8, and 24 hr. In separate groups of animals, also exposed either to filtered air or to 1 ppm O3, plasma eicosanoid (EC) concentrations were measured at 2, 8, 24, 48, or 72 hr after exposure. Significant increases in thromboxane B2 concentrations were seen at 2, 24, and 48 hr after exposure. Plasma concentrations of 6-keto prostaglandin F1 alpha (PGF1 alpha) and prostaglandin E1 (PGE1) were increased at 24 hr and at 24, 48, and 72 hr, respectively. The nature of this long-term pulmonary response to a short-term exposure to O3 suggests alveolar involvement, including probable alveolar duct constriction and localized pulmonary edema. Although changes in plasma EC concentrations were observed concurrent with impaired lung functions, no simple causal relationship was apparent from these studies.

6-Ketoprostaglandin F1 alpha↗

PubMed2002

Effects of noninvasive ventilation on lung hyperinflation in stable hypercapnic COPD.

Two previous uncontrolled studies have suggested that noninvasive mechanical ventilation (NIMV) in patients with hypercapnic chronic obstructive pulmonary disease (COPD) improves arterial blood gas tensions by decreasing lung hyperinflation with the consequent reduction in inspiratory loads and changes in ventilatory pattern. The aim of this randomised placebo-controlled study was to determine whether these mechanisms play a pivotal role in the effects of NIMV on arterial blood gases. Thirty-six stable hypercapnic COPD patients were randomly allocated to NIMV or sham NIMV. A 2-week run-in period was followed by a 3-week study period, during which ventilation was applied 3 h x day(-1), 5 days a week. Arterial blood gases, spirometry, lung volumes, and respiratory mechanics were measured before and after application of NIMV. Patients submitted to NIMV showed changes (mean (95% confidence interval)) in daytime arterial carbon dioxide tension (Pa,CO2) and arterial oxygen tension of -1.12 (-1.52-0.73) kPa (-8.4 (-11.4-5.5) mmHg) and 1.14 (0.70-1.50) kPa (8.6 (5.3-11.9) mmHg), respectively. Total lung capacity, functional residual capacity (FRC) and residual volume were found to be reduced by 10 (7-13), 25 (18-31), and 36 (27-45)% of their predicted value, respectively, whereas forced expiratory volume in one second and forced vital capacity increased by 4 (1.5-6.9) and 9 (5-13)% pred, respectively. Tidal volume (VT) increased by 181 (110-252) mL. All of the above changes were significant compared with sham NIMV. Changes in Pa,CO2 were significantly related to changes in dynamic intrinsic positive end-expiratory pressure, inspiratory lung impedance, VT and FRC. It was concluded that the beneficial effects of noninvasive mechanical ventilation could be explained by a reduction in lung hyperinflation and inspiratory loads.

Aged↗

PubMed1980

Abnormalities in maximum flow volume curve and closing volume in patients with hepatic cirrhosis.

Pulmonary functions were measured in 53 patients with hepatic cirrhosis in whom there was no clinical or radiographic evidence of pulmonary involvement. Spirometric tests such as total lung capacity, vital capacity, functional residual capacity, residual volume and forced expiratory volume during one second were within normal ranges, in all subjects. Flow volume curve and closing volume tests, however, were abnormal in the majority. The maximal expiratory flow at 50 per cent of vital capacity was not altered but the maximal expiratory flow at 25 percent of vital capacity was decreased significantly in patients with hepatic cirrhosis. The closing volume in patients with hepatic cirrhosis was also significantly increased. The abnormalities in flow volume curve and closing volume curve were also demonstrated in non-smokers, and at any age, in cases of hepatic cirrhosis. These results suggested that the narrowing or closure in small airways may occur in patients with hepatic cirrhosis. These changes may be due to mechanical compression of small airways but interstitial edema which was induced by presence in the circulating blood of vasoactive substances and endotoxins.

Adult↗

PubMed1985

Functional and morphologic changes in the lungs of guinea pigs exposed to freshly generated ultrafine zinc oxide.

Guinea pigs were exposed by nose only for 3 hr/day for 6 days to freshly formed zinc oxide (ZnO) particles (projected area diameter = 0.05 micron, sigma g = 2.0) at 5 mg/m3, the currently recommended threshold limit value (TLV). Ventilation, lung mechanics, lung volumes, and diffusing capacity for carbon monoxide (DLCO) in anesthetized, tracheostomized animals at 1, 24, 48, or 72 hr after the end of the last exposure were evaluated. At the same time intervals lung weight, lung fluid content, respiratory epithelial permeability to horseradish peroxidase, gross and microscopic appearance, and [3H]thymidine labeling of nuclei of bronchial and bronchiolar epithelial cells in other groups of animals were measured. Vital capacity, functional residual capacity, alveolar volume, and DLCO were all decreased following the last exposure and did not return to normal values by 72 hr. Increases in flow resistance and decreases in compliance and total lung capacity returned to normal by 72 hr. Lung weights were elevated due to inflammation involving the proximal portion of the alveolar ducts and adjacent alveoli. These changes were still present at 72 hr. [3H]Thymidine labeling of bronchiolar epithelial cell nuclei was increased for 48 hr. Respiratory epithelial permeability to horseradish peroxidase was not affected by the exposures. These results suggest that the current TLV for ZnO may not be adequate.

Animals↗

PubMed1987

Functional changes in the lungs of guinea pigs exposed to sodium sulfite aerosols.

Guinea pigs were exposed head only for 1 hr to submicrometer sodium sulfite aerosols (mass median aerodynamic diameter = 0.36 micron, sigma g = 2.96) at 474, 669, and 972 micrograms SO3(2-)/m3. Respiratory mechanics were measured in unanaesthetized animals before, during, and after exposure. Dose-related increases in resistance and decreases in compliance were observed. At 972 micrograms SO3(2-)/m3, the sodium sulfite aerosol caused a 50% increase in resistance and a 19% decrease in compliance. These changes were still present 1 hr after the end of exposure. The results were used to assess the irritant potency of sodium sulfite aerosol. Another group of guinea pigs was exposed whole body for 1 hr to the same aerosol at 0, 204, 395, and 1152 micrograms SO3(2-)/m3. Immediately after the exposures, lung volume, diffusion capacity for carbon monoxide (DLCO), and wet lung weight were evaluated in anesthetized, tracheotomized animals. As compared to controls, total lung capacity, vital capacity, functional residual capacity, residual volume, and DLCO were all decreased with increasing concentrations of sodium sulfite. Dose-related increases in wet lung weights were also observed. These results were compared with the irritant responses of animals exposed to zinc oxide and sulfur dioxide mixed under different conditions of temperature and humidity.

Aerosols↗

PubMed1988

Oronasal obstruction, lung volumes, and arterial oxygenation.

The effects were studied on lung volumes of partial (chronic) nasal obstruction, total overnight nasal occlusion with a nasal pack, and interdental wiring for 6-8 weeks. Total lung capacity, functional residual capacity, and residual volume decreased significantly with total nasal occlusion and with surgical relief of chronic nasal obstruction. All three volumes increased with interdental wiring. It is concluded that these effects are a result of changes in oronasal resistance: lung volume is enlarged by an overall increase in resistance and diminished by a decrease in resistance. These findings imply that the resistance to expiration provided by the nose helps maintain lung volumes and so may indirectly determine arterial oxygenation.

Adolescent↗

PubMed1987

Augmentation of elastase-induced emphysema by cigarette smoke: effects of reducing tar and nicotine content.

The effects of reducing the tar and nicotine concentration of cigarette smoke were examined in a rat model of smoke-augmented, porcine pancreatic elastase- (PPE-) induced, pulmonary emphysema. Sixty-eight female Long-Evans rats were divided approximately evenly into seven groups: control, PPE, PPE plus sham smoke, high-tar/nicotine cigarette smoke (2R1; 38.8 mg total particulate matter and 2.2 mg nicotine per cigarette), low-tar/nicotine cigarette smoke (1R4F; 10.8 mg total particulate matter and 0.8 mg nicotine per cigarette), PPE + 2R1, and PPE + 1R4F. Three days after intratracheal administration of PPE (400 IU/kg), animals in the smoke-treated groups were exposed to 8-10 puffs of cigarette smoke daily, 7 d/wk for 12 wk. Sham-treated animals received room air in place of cigarette smoke. At the conclusion of the exposures, pulmonary function tests were performed under general anesthesia. Cigarette-smoke exposure alone did not produce significant changes in pulmonary function. Elastase-treated groups demonstrated significant increases in total lung capacity, functional residual capacity, and dynamic and static compliance, as well as significant decreases in carbon monoxide (CO) diffusing capacity and CO diffusion coefficient. Morphometric measurements of mean linear intercept demonstrated a loss of alveolar fine structure with enlargement of distal airspaces in PPE-treated rats. Exposure to either 2R1 or 1R4F cigarette smoke significantly enhanced many of the emphysematous changes produced by PPE, but there were no significant differences between the effects of the two smokes. These data indicate that reducing the tar and nicotine concentration of cigarette smoke does not lessen its ability to augment PPE-induced pulmonary emphysema in the rat.

Animals↗

PubMed1985

Effects of pneumothorax or pleural effusion on pulmonary function.

The effects of pneumothorax or pleural effusion on respiratory function as measured by the commonly applied tests were investigated by studying 13 patients (six with pneumothorax, seven with effusion) with and, as far as possible, without air or fluid in the pleural cavity. Measurements included spirometric volumes, carbon monoxide transfer factor (TLCO), and KCO by the single breath method, maximum expiratory flow-volume curves, and subdivisions of lung volume estimated by both inert gas dilution and body plethysmography. In patients with pneumothorax "pleural volume" was estimated as the difference between lung volumes measured by dilution and thoracic gas volume measured by plethysmography. In patients with effusion the change in "pleural volume" was equated with the volume of fluid subsequently aspirated. "Total thoracic capacity" (TTC) was estimated by adding total lung capacity (TLC) measured by dilution and "pleural volume." Both effusion and pneumothorax produced a restrictive ventilatory defect with reductions of vital capacity, functional residual capacity, and TLC. In the patients with effusion TTC fell after aspiration, suggesting that the pleural fluid produced relative expansion of the chest wall as well as compression of the lung. In patients with pneumothorax, however, there was no difference in TTC with and without air in the pleural space. In the presence of pleural air or fluid there was a slight decrease in TLCO and increase in KCO, with a small but significant increase in the rate of lung emptying during forced expiration.

Adolescent↗