Biomedical subjects

C Jadue

Publications and source records attributed to C Jadue.

5 recordsLinked to original sources

PubMed1986

A comparison of the bronchodilating effects of a beta-2 adrenergic agent (albuterol) and an anticholinergic agent (ipratropium bromide), given by aerosol alone or in sequence.

We evaluated the effect of anticholinergic and beta-adrenergic inhaled bronchodilators, alone or in sequence, in 11 patients with chronic obstructive pulmonary disease. We compared the agents albuterol and ipratropium bromide when each was used as a single aerosol in the maximal dose. After giving a maximal dose of one agent, we compared the effect of adding the other with that of adding a placebo. When used alone, both bronchodilators significantly increased airflow and relieved hyperinflation, and there was no significant difference between the two. After the improvement with the initial bronchodilator, the subsequent effect of a second inhaled bronchodilator was not greater than that of placebo. These results suggest that in the treatment of chronic obstructive pulmonary disease, these two aerosols are usually equipotent in maximal doses and the addition of a second agent is of no practical value. The data support the prescription of a single inhaled agent in most cases but do not rule out the value of combinations of agents under special circumstances.

Aerosols↗

PubMed1985

Forced expiration and HeO2 response in canine peripheral airway obstruction.

We examined the effect of peripheral airway obstruction on parameters of maximum expiratory flow (Vmax) in a canine model of bronchiolitis obliterans (B). B was produced by the repeated intrabronchial instillations of a 1% nitric acid solution in seven dogs (group B). In seven control dogs (group C), a normal saline solution was used. During forced vital capacity deflation, Vmax on air, the relative increase in Vmax on 80% He-20% O2 (delta Vmax), and airway sites of flow limitation "choke points" (CP) were determined at multiple lung volumes (VL). The findings were interpreted in terms of the wave-speed theory of flow limitation. Wave-speed parameters were identified with a pressure-measuring device positioned in the airway. Compared with the findings for group C, Vmax decreased substantially at the lower VL (less than 50% vital capacity) in group B, whereas there were no changes in delta Vmax at any VL. CP were identified in central airways in both groups but were slightly more upstream in group B. Our analysis indicated that the reduction in Vmax in group B was due to an increase in upstream frictional pressure losses (Pfr) that caused a relative reduction in the pressure head, so that choking occurred in slightly upstream airways. delta Vmax did not change in group B because with CP identified in central airways, Pfr were density dependent, and significant differences in head loss on the two gas mixtures did not occur. Choking therefore occurred with similar wave-speed variables on the two gas mixtures, and delta Vmax was maintained.

Airway Obstruction↗

PubMed1985

Effects of upper or lower airway anesthesia on hypercapnic ventilation in humans.

To evaluate the contribution of vagal airway receptors to ventilatory control during hypercapnia, we studied 11 normal humans. Airway receptor block was induced by inhaling an aerosol of lidocaine; a preferential upper oropharyngeal block was also induced in a subgroup by gargling a solution of the anesthetic. Inhalation of lidocaine aerosol adequate to increase cough threshold, as measured by citric acid, did not change the ventilatory response to CO2, ratio of the change in minute ventilation to change in alveolar PCO2 (delta VI/delta PACO2), compared with saline control. Breathing pattern at mean CO2-stimulated ventilation of 25 l/min showed significantly decreased respiratory frequency, increased tidal volume, and prolonged inspiratory time compared with saline. Resting breathing pattern also showed significantly increased tidal volume and inspiratory time. In nine of the same subjects gargling a lidocaine solution adequate to extinguish gag response without altering cough threshold did not change delta VI/delta PACO2 or ventilatory pattern during CO2-stimulated or resting ventilation compared with saline. These results suggest that lower but not upper oropharyngeal vagal airway receptors modulate breathing pattern during hypercapnic as well as resting ventilation but do not affect delta VI/delta PACO2.

Adult↗

PubMed1984

Pulmonary function tests in the detection of small airway obstruction in a canine model of bronchiolitis obliterans.

We compared parameters of maximal expiratory flow with other tests used in the detection of small airways obstruction (SAD) in a canine model of bronchiolitis obliterans. Bronchiolitis was produced by instilling a 1% solution of nitric acid into the airways of 8 dogs (Group N). In 5 control dogs, a normal saline solution was instilled (Group C). Plethysmographic lung volumes, oscillatory airway resistance (RL), and tests for SAD were examined after bronchiolitis was produced. To evaluate peripheral airway function, the single-breath nitrogen washout curve was used to obtain the slope of phase III and to estimate the lung volume at which a terminal increase in N2 concentration was observed (closing capacity). Maximal expiratory flow-volume curves while the dogs breathed air and 80:20 helium:oxygen (HeO2) were performed to obtain the air flow rate at 50% vital capacity (V50), the corresponding HeO2 flow rate (delta Vmax), and the lung volume at which air and HeO2 flow rates were equal (Viso). After injury, the histologic aspects of the lung in Group N showed acute and chronic inflammation of the small airways. The RL did not change in Group N, despite a relative increase in peripheral airway resistance, which when measured increased about 4 times. Compared with Group C, significant increases in closing capacity and Viso and significant decreases in V50 were observed in Group N. Although predicted to decrease in SAD, delta Vmax did not change. We conclude that delta Vmax is relatively insensitive to SAD. Possible mechanisms resulting in reduced V50 but maintained delta Vmax in this model were further examined in terms of the concepts outlined by the wave-speed theory of flow limitation.

Airway Obstruction↗

PubMedDate not supplied

[Thoracic actinomycosis].

Thoracic actinomycosis was identified in a 14 year old girl. The disease is infrequent in children and diagnosis is difficult. The occurrence of a protracted pulmonary lesion, together with osteomyelitis of several ribs and by fistulae formation in the chest wall, with production of characteristic "sulfur granules", were the key elements to suspect the right diagnosis, which was confirmed by a bacteriological and histological studies. Treatment with high doses of intravenous penicillin, 3 million U four times a day for 4 weeks, followed by long term oral therapy with the same drug was done, with remission of pulmonary, osseous and cutaneous lesions.

Actinomycosis↗