The European respiratory journal : official journal of the European Society for Clinical Respiratory Physiology
-
Clinical Trial Controlled Clinical Trial
Lung and chest wall mechanics in patients with acquired immunodeficiency syndrome and severe Pneumocystis carinii pneumonia.
The aim of this study was to assess the mechanical characteristics of the respiratory system in patients with acquired immune deficiency syndrome (AIDS) and acute respiratory distress syndrome (ARDS) caused by Pneumocystis carinii pneumonia (PCP). In 12 mechanically ventilated patients, total respiratory system mechanics was assessed using the technique of rapid airway occlusion during constant flow inflation, and was partitioned into lung and chest wall components using the oesophageal balloon technique. We measured interrupter resistance (Rint), which mainly reflects airway resistance, additional resistance (deltaR) due to viscoelastic behaviour and time constant inequalities, and static elastance (Est). ⋯ At variance with common observations in the latter patients, none of the AIDS patients with PCP exhibited an inflection point on the static inflation V-P curve, suggesting little or no alveolar recruitment during lung inflation. This finding could be related to the distinctive histopathology of Pneumocystis carinii pneumonia. Indeed, computed tomography revealed homogeneous diffuse interstitial and alveolar infiltration rather than the dense, dependent opacities observed in other studies on acute respiratory distress syndrome of different aetiologies.
-
Clinical Trial Controlled Clinical Trial
Cardiopulmonary exercise testing following hay exposure challenge in farmer's lung.
In patients experiencing an acute episode of hypersensitivity pneumonitis (HP), the alveoli and interstitium show a marked inflammation. The effects of this infiltration with effector cells on gas exchange and the cardiopulmonary system are not well characterized, and there are no data regarding cardiopulmonary exercise testing during hypersensitivity pneumonitis. The aim of this study was to gain new insights into the pathophysiology of acute farmer's lung using cardiopulmonary exercise testing. ⋯ In addition, 40% of the asymptomatic farmers demonstrated a pathological increase of the alveolar to arterial oxygen difference during exercise following exposure. In conclusion, our data signify that acute hypersensitivity pneumonitis induces significant changes in pulmonary gas exchange during exercise. Cardiopulmonary exercise testing may help to identify individuals with possible subclinical farmer's lung disease.
-
Pharmacological ovarian stimulation is an accepted technique for amplifying the normal process of follicular development and maturation. It has been in use for the past decade, especially in cases of infertility. Pleural effusion associated with ovarian hyperstimulation syndrome (OHSS), a complication of this therapy, may be more prevalent than is commonly accepted. ⋯ All of these patients required fluid evacuation for symptomatic relief. Resolution was achieved with supportive measures and rest. Ovarian hyperstimulation syndrome may be common enough to warrant routine consideration in the differential diagnosis of pleural effusion in young women.
-
Comparative Study
Mucociliary clearance in cystic fibrosis knockout mice infected with Pseudomonas aeruginosa.
In this study, we examined whether mucociliary clearance differed between cystic fibrosis (CF) knockout mice and wildtype controls. Additionally, we investigated whether infection with Pseudomonas aeruginosa, a common pathogen in the CF lung, affected this important host defence mechanism. Ciliary beat frequency (fcb) and particle transport (PT) were recorded using an in vitro lung explant preparation. ⋯ While there were no differences detectable in fcb between CFTR -/- mice and their +/+ controls either in the presence or absence of P. aeruginosa, PT rates were different between these groups; interestingly, PT rates appeared dependent on both CFTR and infection status, with uninfected CFTR +/+ animals demonstrating higher rates of PT than their -/- littermates, while CFTR +/+ P. aeruginosa-infected mice demonstrated lower PT than knockout mice. These data demonstrate differences in mucociliary clearance between cystic fibrosis transmembrane conductance regulator knockout mice and controls, and further that Pseudomonas aeruginosa infection affects mucociliary clearance in the peripheral airways of mice. Additionally, the observed differences in particle transport suggest that cystic fibrosis transmembrane conductance regulator knockout mice demonstrate different mucociliary responses to infection.
-
Randomized Controlled Trial Clinical Trial
Lack of effect of high doses of inhaled morphine on exercise endurance in chronic obstructive pulmonary disease.
Systemic opiates may relieve dyspnoea and improve exercise tolerance in patients with chronic obstructive pulmonary disease (COPD). Small doses of inhaled opiates may have similar effects; however, recent studies have shown no benefit. We studied higher doses of inhaled morphine and measured systemic absorption to determine whether any beneficial actions are local or systemic. ⋯ The highest plasma concentration was measured immediately after nebulization, and this decreased steadily in the hour thereafter (p<0.002). There was no correlation between the change in walk distance and the change in plasma morphine concentration after either dose of nebulized morphine. We conclude that higher doses of nebulized morphine do not improve exercise endurance or relieve dyspnoea in patients with chronic obstructive pulmonary disease, and that morphine is rapidly absorbed systemically after inhalation.