Biomedical subjects
Publications and source records attributed to P E Krumpe.
A patient with prior GBF and new-onset hemoptysis was diagnosed as having recurrent GBF by measurement of bronchial secretion pH. This is a previously unreported means of diagnosing this process. Bronchoscopic findings were substantiated by upper GI contrast study and surgical findings.
When evaluating diffuse lung infiltrates, the clinician should place special emphasis on the acuity of symptoms, nonpulmonary complaints and findings, environmental exposures, and risk factors for immunosuppressive diseases. Certain radiographic features, such as the distribution of opacities, hilar adenopathy, Kerley-B lines or pneumothorax, or pulmonary function tests demonstrating air flow limitation also narrow the differential diagnosis. One can direct the subsequent workup based on the narrowed differential diagnosis, the pace of disease, the activity of the ongoing inflammatory-immune process, and the age, overall medical condition, and wishes of the patient. Unless a specific diagnosis (for example, hypersensitivity pneumonitis, the treatment of which is withdrawal of the offending agent) can be made, therapy of noninfectious diffuse lung disease is quite unsatisfactory. Immunosuppressive therapy is indicated to arrest the active inflammatory process with the hope that objective signs of improvement will occur after a 3- to 12-month course. Important areas of basic research in pulmonary fibrosis include cell-cell and cell-matrix interactions in the lung interstitium and delineation of fibroblast biology and cytokine-mediated lung connective tissue pathology. More successful therapies will probably evolve from better understanding of the molecular and cellular biology of the lung fibrogenic process.
Explore the source record for details and available documents.
In this review article, the effects of old age on lung structure and function are discussed. Changes in lung morphology and biochemistry are correlated with changes in lung mechanics and gas exchange, as well as with the respiratory system's adaptability to the stresses of exercise and sleep. The effects of aging on the lungs' defense mechanisms are related to pulmonary diseases of the elderly.
Possible mechanisms by which alcohol may adversely affect the respiratory system are considered. Alcohol ingestion impairs glottic reflexes, and alcoholics are predisposed to pneumonias and lung abscesses from aspiration of oropharyngeal bacteria. Alcohol intoxication also increases the frequency of sleep apnea and may result in respiratory failure from oversedation.
Patients having lobar airway obstruction or consolidation usually have decreases of both ventilation and perfusion on lung scans. We report three patients in whom hypoxic vasoconstriction was apparently incomplete, resulting in a "reversed" ventilation-perfusion mismatch. Perfusion of the hypoxic lobe on the radionuclide scan was associated with metabolic alkalosis, pulmonary venous and pulmonary arterial hypertension in these patients.
Bronchial fistulae in communication with atmospheric pressure can be identified by the presence of a squeaking sound heard over the chest wall during a Valsalva maneuver. Furthermore, these leak sounds can help identify the size, location, and communications of the bronchial fistulae. The size of the leak can be inferred by the pitch of the leak sound. Large leaks produce low pitched sounds, smaller leaks (or partially obstructed leaks) produce high pitched squeaks , and multiple leaking sites produce polyphonic leak squeaks . The bronchus responsible for the leak can be identified by cessation of the leak sound during balloon occlusion of the correct bronchial stump. A communication of a bronchial fistula with the chest wall facial plane produces massive subcutaneous emphysema and an early inspiratory click. This click suggests a check valve mechanism of air exiting the leaking bronchus.
Tracheal sound recordings and O2 saturation were compared with conventional recordings of respiratory events (thermistors, strain gauges, and O2 saturation) in 14 patients referred for assessment of sleep apnea syndrome. There was no significant difference in the number of respiratory events associated with desaturation recorded during the sleep by the two methods. Tracheal sound recordings were more useful in analyzing the cause of the respiratory event. Hypopnea without desaturation was seen more often with tracheal sound recordings than with the conventional methods. The durations of apneic and hypopneic events were significantly longer when recorded by thermistors and strain gauges than by breath sounds.
Explore the source record for details and available documents.
We have evaluated the use of an acoustic gas analyzer (AGA) for the measurement of total lung capacity (TLC) by single-breath helium dilution. The AGA has a rapid response time (0-90% response = 160 ms for 10% He), is linear for helium concentration of 0.1-10%, is stable over a wide range of ambient temperatures, and is small and portable. We plotted the output of the AGA vs. expired lung volume after a vital capacity breath of 10% He. However, since the AGA is sensitive to changes in speed of sound relative to air, the AGA output signal also reports an artifact due to alveolar gases. We corrected for this artifact by replotting a single-breath expiration after a vital capacity breath of room air. Mean alveolar helium concentration (HeA) was then measured by planimetry, using this alveolar gas curve as the base line. TLC was calculated using the HeA from the corrected AGA output and compared with TLC calculated from HeA simultaneously measured using a mass spectrometer (MS). In 12 normal subjects and 9 patients with chronic obstructive pulmonary disease (COPD) TLC-AGA and TLC-MS were compared by linear regression analysis; correlation coefficient (r) was 0.973 for normals and 0.968 for COPD patients (P less than 0.001). This single-breath; estimation of TLC using the corrected signal of the AGA vs. Expired volume seems ideally suited for the measurement of subdivisions of lung volume in field studies.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Laryngeal sounds are produced by air flow across the glottis. We found that apnea could be identified by the cessation of laryngeal sounds during continuous monitoring. We recorded laryngeal sounds using a microphone coupled to a stethoscope head taped to the subject's lateral neck. This signal was conditioned using a commercially available amplifier and displayed on a time-based recorder. Laryngeal sound monitoring of apnea could be useful in sleep studies.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Continuous negative external chest pressure was used to increase the functional residual capacity in 6 dogs, and the effects were compared with the effects of increasing functional residual capacity using positive end-expiratory pressure. Cardiac index and mixed venous O2 stauration each decreased from control values during positive end-expiratory pressure, but did not decrease with continuous negative external chest pressure. Continuous negative external chest pressure may provide an alternative to positive end-expiratory pressure for increasing the functional residual capacity of patients in whom the latter causes unacceptable decreases in venous return and cardiac output.
Explore the source record for details and available documents.