PubMed Health⌕ Search

Biomedical subjects

B Make

Publications and source records attributed to B Make.

13 recordsLinked to original sources
PubMed1995

Quantitative chest computed tomography as a means of predicting exercise performance in severe emphysema.

RATIONALE AND OBJECTIVES: We assessed the value of quantitative high-resolution computed tomography (CT) as a diagnostic and prognostic tool in smoking-related emphysema. METHODS: We performed an inception cohort study of 14 patients referred with emphysema. The diagnosis of emphysema was based on a compatible history, physical examination, chest radiograph, CT scan of the lung, and pulmonary physiologic evaluation. RESULTS: As a group, those who underwent exercise testing were hyperinflated (percentage predicted total lung capacity +/- standard error of the mean = 133 +/- 9%), and there was evidence of air trapping (percentage predicted respiratory volume = 318 +/- 31%) and airflow limitation (forced expiratory volume in 1 sec [FEV1] = 40 +/- 7%). The exercise performance of the group was severely limited (maximum achievable workload = 43 +/- 6%) and was characterized by prominent ventilatory, gas exchange, and pulmonary vascular abnormalities. The quantitative CT index was markedly elevated in all patients (76 +/- 9; n = 14; normal < 4). There were correlations between this quantitative CT index and measures of airflow limitation (FEV1 r2 = .34, p = 09; FEV1/forced vital capacity r2 = .46, p = .04) and between maximum workload achieved (r2 = .93, p = .0001) and maximum oxygen utilization (r2 = .83, p = .0007). CONCLUSION: Quantitative chest CT assessment of disease severity is correlated with the degree of airflow limitation and exercise impairment in pulmonary emphysema.

Aged↗
PubMed1991

COPD: management and rehabilitation.

Chronic obstructive pulmonary diseases include emphysema, chronic bronchitis and asthma. Patients with mild disease may remain asymptomatic for many years. In patients with a sedentary lifestyle, 60 percent of lung function may be lost before shortness of breath occurs during daily activity. Spirometry may detect mild to moderate airflow obstruction in asymptomatic patients. Goals of therapy include reduction of airflow obstruction, prevention or treatment of complications, and improvement in quality of life.

Bronchodilator Agents↗
PubMed1989

Controlled trial of external negative pressure ventilation in patients with severe chronic airflow obstruction.

The effect of intermittent external negative pressure ventilation (ENPV) with the Emerson Pulmowrap ventilator upon leg cycle endurance time (ET), maximal transdiaphragmatic pressure (Pdimax), breathing pattern as expressed by the tension time index (TTdi), and sense of well being was studied in 16 patients with severe chronic airflow obstruction (CAO). The patients were randomized to 3 wk of in-hospital pulmonary rehabilitation (Group I, seven patients) or the same program plus ENPV (Group II, nine patients). Both groups were similar in terms of age (65 +/- 8 versus 61 +/- 13 yr), severity of CAO (FEV1 of 0.64 +/- 0.14 versus 0.59 +/- 0.18 L), and PaCO2 (44 +/- 9 versus 45 +/- 7 mm Hg). Blood theophylline levels and nutritional status were also similar in both groups. Baseline ET (2.9 +/- 0.6 versus 3.8 +/- 1.6 min) and Pdimax (45 +/- 15 versus 56 +/- 18 cm H2O) were decreased in both groups. Baseline TTdi was high but similar in both groups; at rest the values were 0.15 +/- 0.05 versus 0.16 +/- 0.04, and at end-exercise they were 0.17 +/- 0.06 versus 0.21 +/- 0.12. After treatment FEV1 and Pdimax remained unchanged, but the patients in both groups manifested clinical improvement and had a significant increase in mean ET (Group I from 2.9 to 6.9 and Group II from 3.8 to 6 min, p less than 0.01). TTdi decreased both at rest (0.14 +/- 0.07 versus 0.13 +/- 0.04) and at end-exercise (0.14 +/- 0.06 versus 0.15 +/- 0.09) with no difference between groups.(ABSTRACT TRUNCATED AT 250 WORDS)

Airway Obstruction↗
PubMed1987

Respiratory muscle dysfunction secondary to chronic tracheostomy tube placement.

In patients requiring periodic mechanical ventilation, a deflated, fenestrated tracheostomy tube may impair respiratory muscle performance during spontaneous breathing. We describe a patient with severe chronic airflow obstruction (CAO) whose respiratory muscle performance and exercise duration improved after tracheostomy tube removal. Duty cycle, Pdi/Pdi max, and the tension time index were all lower during exercise after tracheostomy tube removal. We conclude that a deflated and fenestrated tracheostomy tube significantly increases airways resistance and can further limit ventilatory muscle performance in patients with airflow obstruction. Patients requiring intermittent ventilatory support may benefit from permanent tracheostomy fistulas that allow for intermittent self cannulation. This would avoid loading of the respiratory muscles when breathing spontaneously.

Airway Obstruction↗
PubMed1985

Respiratory consequences of abdominal hernia in a patient with severe chronic obstructive pulmonary disease.

The diaphragm is the most important muscle of respiration. It is believed that the abdominal contents affect diaphragmatic contraction by helping determine its length tension state and by acting as a fulcrum for this muscle to lift the rib cage and thereby increase lung volume. In support of these concepts we describe a patient with severe chronic obstructive pulmonary disease and a large midline hernia of the abdomen who, when standing, had a gastric pressure (Pg) of 4 cm H2O and a maximal transdiaphragmatic pressure (Pdimax) of 14 cm H2O. This was associated with an O2 saturation of 82%, lower thoracic and upper abdominal paradoxical breathing, and severe dyspnea. Once the hernia was reduced there was a rise in Pg to 12 cm H2O, of Pdimax to 27 cm H2O, and of O2 saturation to 89%. There was normalization of the breathing pattern and a decrease in dyspnea. Reduction of this patient's abdominal hernia resulted in an increase in her exercise tolerance.

Abdomen↗
PubMed1985

Physiologic closure of a symptomatic patent foramen ovale with oxygen therapy.

Surgery is required for correction of a physiologically significant patent foramen ovale. We report a patient with poliomyelitis and respiratory failure in whom a patent foramen ovale became symptomatic because of hypoxemia-induced pulmonary hypertension. Oxygen therapy and mechanical ventilation reversed the pulmonary hypertension, resulting in physiologic termination of the patent foramen ovale without surgery.

Aged↗
PubMed1984

Rehabilitation of ventilator-dependent subjects with lung diseases. The concept and initial experience.

Sixteen ventilator-dependent patients were enrolled in an in-patient pulmonary rehabilitation (PR) program in a university medical center with the goals of achieving independent self-care, mobility and discharge home. Ten patients had chronic obstructive pulmonary disease and six had restrictive respiratory disorders. PR by a multi-disciplinary team consisted of five phases: 1) stabilization; 2) evaluation; 3) rehabilitation planning including motivation by allowing speech and mobility; 4) rehabilitation training encouraging independent performance of activities of daily living (ADL); and 5) discharge planning with training of patients and families in home respiratory care techniques. A key aspect of the program is improving independence early in the program through the use of mobile ventilators. Periods of weaning from ventilatory support for two or more hours per day were of great importance in improving patient mobility and independence in ADL. Twelve patients were discharged home; except for two individuals who were severely limited by neuromuscular disease, all patients were largely independent in ADL in the home. This preliminary report demonstrates the feasibility of training ventilator-dependent persons to be independent and to participate in their own care in the home.

Activities of Daily Living↗
PubMed1978

Diagnosis and management of hypoxemia.

The following steps are necessary in the successful management of hypoxia: 1. Establish the presence of hypoxemia with measurements of arterial blood gases. 2. Search for signs of tissue hypoxia. 3. Assign a physiologic cause for hypoxemia. 4. Begin oxygen therapy by a method appropriate to underlying pathophysiologic mechanism, as outlined in Table 2. 5. Repeat arterial blood gas measurements to assure adequate reversal of hypoxemia. 6. Treat any underlying disease(s).

Humans↗
PubMed1975

Factors influencing the measurement of closing volume.

The various factors influencing closing volume were studied by performing the single-breath N2 test on 9 healthy nonsmokers. Time of day, day of the week, and preceding volume history had no effect on either closing volume or alveolar plateau. Slow inspiratory flow resulted in larger ratio of closing volume to vital capacity, ratio of closing capacity to total lung capacity, and change in N2 concentration than fast inspiratory flow. Voluntary regulation of the expiratory flow resulted in smaller ratios of closing volume to vital capacity and closing capacity to total lung capacity than when flow was regulated by a resistance. Prolonged breath holding of the inspired O2 led to larger ratio of closing volume to vital capacity and ratio of closing capacity to total lung capacity. To obtain uniform, comparable closing volumes, it is suggested that the subject inspire slowly, control expiratory flow (preferably voluntarily), and not pause between inspiration and expiration.

Adult↗
PubMed1975

Medical surveillance for occupational respiratory diseases.

Three simple procedures should be used to monitor industrial populations for the development of respiratory disease: (1) History, (2) chest x-ray, and (3) spirometry. The history should be complete and include occupational as well as medical information. Only a P-A x-ray examination of the chest is necessary. Accurate performance of spirometry with reliable equipment can provide useful evidence of physiologic impairment. Serial test results from each employee should be carefully compared to best assess the early development of occupational respiratory disease.

Forced Expiratory Volume↗