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Biomedical subjects

H A Lyons

Publications and source records attributed to H A Lyons.

At least 19 recordsLinked to original sources
PubMed1979

A comparative study of bronchodilator effects of carbuterol and ephedrine.

The bronchodilator effect of carbuterol hydrochloride, a new adrenergic agonist, was compared with that of ephedrine sulfate in 12 patients with bronchial asthma. A 2-mg dosage of carbuterol hydrochloride, three times daily, was used in comparison with a 25-mg dosage of ephedrine sulfate, three times daily. The drugs were orally administered for ten-day periods in a double-blind, randomized manner. After carbuterol therapy, the mean increases in forced expiratory volume in one second and midmaximal expiratory flow rate were significantly greater in a four-hour period than those noticed with ephedrine. A decrease in bronchodilator response to both drugs was noticed on the tenth day. No side effects were noticed with carbuterol at the aforementioned dosage. The results of our study indicate that carbuterol is a safer and more effective bronchodilator than ephedrine.

Administration, Oral↗
PubMed1979

P pulmonale in status asthmaticus.

We studied 129 patients during acute, severe asthmatic attacks. Electrocardiograms showed P pulmonale in 49% of patients who had an arterial carbon dioxide tension (PaCo2) greater than or equal to 45 mm Hg and an arterial pH less than or equal to 7.37, whereas P pulmonale was present in only 2.5% of asthmatics who had a PaCO2 less than or equal to 44 mm Hg and a pH greater than or equal to 7.38 (p less than 0.001). P wave and QRS axes were 79 +/- 8 degrees and 80 +/- 20 degrees, respectively, in the presence of P pulmonale. When P pulmonale disappeared, the P wave and QRS axes shifted significantly to the left (p less than 0.001). Electrocardiographic P pulmonale persisted 12 to 60 hr after correction of hypoxemia, hypercapnia, and acidosis. In 7 patients with P pulmonale and respiratory acidosis, cardiac catheterization demonstrated normal artery pressures (PAPs) measured relative to atmospheric pressure. In 12 of these peak inspiratory pulmonary artery transmural pressures (PATPs) were increased. Since increased right heart transumural pressures could result in chamber distention, these data are consistent with the hypothesis that reversible P pulmonale in status asthmaticus is explainable on the basis of markedly negative tidal pleural pressures and increased right heart transmural pressures.

Adolescent↗
PubMed1979

Collateral ventilation in excised human lungs.

Collateral ventilation was determined in 13 isolated human lungs obtained at postmortem. These included lungs from patients with pneumonia (2 cases), metastatic breast carcinoma (3), emphysema (5), pulmonary fibrosis (2) and hemorrhagic abscess (1). The amount of collateral ventilation was variable and related to the pathological process within the lung. Flow and resistance of collateral pathways were determined for each studied lung. Demonstration of collateral flow was made with the use of 133Xe and recorded by radiographic imaging. Further demonstration of the collateral pathways was done by use of 1 micrometer sized particles of tantalum. Histological examination showed tantalum dust to accumulate at gaps in the alveolar wall at the lobar junction and to pass through this area. Although the sample population is small, no correlation was found for age and the amount of flow through the channels. This study demonstrated that alveolar pores play a role in collateral ventilation. No collateral flow was observed in six pediatric lungs tested. It is likely that collateral ventilation is an acquired phenomenon in humans.

Aged↗
PubMed1979

Pulmonary sarcoidosis: roentgenographic, functional, and pathologic correlations.

Discrepancies were observed between functional (PFT), chest roentgenographic, and open lung biopsy findings (granulomata, interstitial pneumonitis, angiitis, and fibrosis) in 81 patients with clinical diagnosis of sarcoidosis. A combination of normal PFT and Type 1 roentgenographic findings (hilar lymphadenopathy) was associated with minimal lung lesions without fibrosis. Type 1 findings alone did not preclude extensive lesions or fibrosis. Advanced roentgenographic and PFT abnormalities correlated with the presence of extensive lung lesions. The pulmonary diffusing capacity correlated best with specific and overall lung pathology, and roentgenographic types. Only this test differentiated the extent of granulomata and the roentgenographic types. Moderate degrees of other pathologic changes were not distinguished by any other PFT. Degrees of overall lung pathology correlated with an individual PFT and most significantly with overall PFT (p less than 0.001). Serial studies of PFT are a practical and valuable means for assessment of the disease process in sarcoidosis.

Adolescent↗
PubMed1978

Tuberculous mediastinal lymphadenitis in the adult.

The authors present the roentogenological findings and response to treatment of 10 patients with tuberculous mediastinal lymphadenitis (TML). The clinical presentation is usually nonspecific except for the positive tuberculin skin test. The roentgenographic appearance varies but very often includes right tracheobronchial involvement. Tissue diagnosis is often necessary to establish the diagnosis. Since the epidemiology of tuberculosis is shifting, TML will be encountered more frequently in the adult.

Adolescent↗
PubMed1978

Indications for the use of tranylcypromine and trifluoperazine (Parstelin).

Thirty-two patients were treated with the combination of tranylcypromine and trifluoperazine (Parstelin). The patients fell into 3 clinical groups, namely, endogenous depression (7 patients), neurotic depressive reaction (10 patients) and phobic anxiety with some depressive features (15 patients). Satisfactory response was found in 10 out of the 15 patients with phobic symptoms. The response in the other 2 groups was not significant. Side effects were troublesome in the neurotic depressive reaction group. In the phobic group the symptoms of the patients who responded were inclined to recur when the treatment was discontinued. It is considered that it is a useful preparation in the treatment of some phobic patients, but one must expect that the patients are likely to have to remain on the drug for long periods of time.

Adult↗
PubMed1978

Nongranulomatous interstitial pneumonitis in sarcoidosis. Relationship to development of epithelioid granulomas.

Nongranulomatous, nonspecific interstitial pneumonitis was a predominating or prominent histopathologic finding in 62 percent of 128 granuloma-containing specimens from open lung biopsies obtained from patients with sarcoidosis. Data from this study, combined with observations by others on the evolution of experimentally induced granulomas, indicate that interstitial pneumonitis represents a very early lesion, possibly the initial lesion, in pulmonary sarcoidosis. Because of the relatively large error of sampling inherent in the currently increasing practice of obtaining small specimens for lung biopsy via the flexible fiberoptic bronchoscope, we anticipate that interstitial pneumonitis will be seen as the only histopathologic finding in these specimens with increasing frequency. It is therefore important to recognize that interstitial pneumonitis is a characteristic, although nondiagnostic, morphologic feature of pulmonary sarcoidosis.

Adolescent↗
PubMed1977

A comparative study of subcutaneously administered terbutaline and epinephrine in the treatment of acute bronchial asthma.

Terbutaline, a new bronchodilator drug reported to have selective affinity for beta 2-adrenergic receptors, was compared with epinephrine in the treatment of 49 adult subjects with acute bronchial asthma. Under double-blind conditions, 24 subjects received 1.0 mg of terbutaline sulfate, and 25 subjects received 0.5 mg of epinephrine hydrochloride subcutaneously. Spirometric measurements, heart rate, and blood pressure, as well as subjective responses, were recorded prior to, and then at 5, 15, 30, 60, and 120 minutes after administration of the drug. The results indicate that terbutaline is an effective bronchodilator drug in subjects with acute asthma; however, the heart rate rose significantly after administration of terbutaline, with a maximal increase of 25 percent above control. Review of the literature reveals that tachycardia is a consistent finding when subcutaneous doses of terbutaline in excess of 0.25 mg are administered. Stimulation of beta 1-adrenergic receptors in the heart appears to be the most important factor involved in this response. A lesser cardioaccelerator effect was observed after administering epinephrine in a dose producing an equivalent degree of bronchodilatation.

Acute Disease↗
PubMed1977

Occurrence of lung granulomas in patients with stage I sarcoidosis.

Granulomas were found in the lungs of 21 consecutive patients with stage I sarcoidosis who underwent open lung biopsy. The extent of granulomatous disease and fibrosis was significantly less (P less than .05) than seen in open lung biopsies from larger groups of patients with stage II and stage III sarcoidosis. The results of this study support what had previously been widely suspected: that is, if sufficient lung tissue is studied microscopically, granulomas will be found in the lungs of all patients having sarcoidosis with mediastinal lymphadenopathy but not radiographically demonstrable lung abnormalities.

Granuloma↗
PubMed1977

Serum angiotensin converting enzyme in sarcoidosis: clinical significance.

The elevated activity of serum angiotensin converting enzyme (ACE) in sarcoidosis was usually reduced during steroid therapy but remained above the normal value (52 nmol-min-1-ml-1) in approximately a third of patients during the first year of therapy. ACE was elevated in 5 of 10 patients treated with steroids for at least four years. It was significantly higher in untreated patients (placebo group), who were subsequently placed on steroid therapy because of clinical deterioration, than in those remaining on placebo therapy. In general ACE tended to diminish with increasing duration of disease. The results suggest that serial study of ACE may be useful in the clinical management of sarcoidosis, including assessment of the degree of activity, the need for steroid therapy, therapeutic result and the prognosis.

Adult↗
PubMed1977

Increased serum angiotensin converting enzyme activity in sarcoidosis.

The activity of serum angiotensin converting enzyme (ACE), assayed fluorometrically with the substrate hippuryl-L-histidyl-L-leucine was significantly higher in 116 patients with sarcoidosis than in 415 patients with other diseases--pulmonary and nonpulmonary--and in 58 normal subjects. Serum ACE was elevated in 59% of 46 recently diagnosed, untreated patients with sarcoidosis and was significantly reduced following steroid therapy in three patients with sarcoidosis, but in only one of four patients treated with placebos. The results suggest that elevated serum ACE activity is a valuable, although not absolutely specific, diagnostic indicator of sarcoidosis. It should be stressed that a normal value does not rule out the disease, and that steroid therapy tends to reduce the serum ACE activity.

Adult↗
PubMed1977

Granulomatous pulmonary angiitis in sarcoidosis.

The occurrence and morphologic aspects of granulomatous pulmonary angiitis were evaluated in open lung biopsy specimens from 128 patients with sarcoidosis. All of the specimens showed parenchymal granulomas characteristic of sarcoidosis, and in 88(69%), granulomatous angiitis was seen. In the speclimens that exhibited granulomatous angiitis, venous involvement was mos common, seen in 92% of the cases. In 61% of these biopsy specimens, only venous involvement was seen; in 31%, both venous and arterial involvement was present. Only 8% of the positive specimens showed arterial lesions exclusively. The extent of angiitis was quantitated. Focal segmental elastic tissue destruction, partial or complete, was a common finding. No instances of aneurysm formation, endothelial erosion, or thrombosis were observed. Occlusive narrowing of small vessels was frequent. Bronchial blood vessels were not involved.

Adolescent↗