American journal of respiratory and critical care medicine
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Am. J. Respir. Crit. Care Med. · Jul 1998
Multicenter StudyNoninvasive monitoring of cardiac output in critically ill patients using transesophageal Doppler.
Measurement of cardiac output using thermodilution technique in mechanically ventilated patients is associated with significant morbidity. The goal of the present study was to assess the validity of cardiac output measurement using transesophageal Doppler in critically ill patients. Forty-six patients from three different intensive care units underwent 136 paired cardiac output measurements using thermodilution (COTH) and transesophageal Doppler (COTED). ⋯ Variations in cardiac output between two consecutive measures using either transesophageal Doppler or thermodilution techniques were similar in direction and magnitude (bias = 0 L/min; limits of agreement = +/-1.7 L/min). Suprasternal Doppler and indirect calorimetry yielded similar correlations and agreements in the subset of patients in whom they were used. These results confirm that transesophageal Doppler can provide a noninvasive, clinically useful estimate of cardiac output and detect hemodynamic changes in mechanically ventilated, critically ill patients.
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Am. J. Respir. Crit. Care Med. · Jul 1998
Acute respiratory distress syndrome caused by pulmonary and extrapulmonary disease. Different syndromes?
To assess the possible differences in respiratory mechanics between the acute respiratory distress syndrome (ARDS) originating from pulmonary disease (ARDSp) and that originating from extrapulmonary disease (ARDSexp) we measured the total respiratory system (Est,rs), chest wall (Est,w) and lung (Est,L) elastance, the intra-abdominal pressure (IAP), and the end-expiratory lung volume (EELV) at 0, 5, 10, and 15 cm H2O positive end-expiratory pressure (PEEP) in 12 patients with ARDSp and nine with ARDSexp. At zero end-expiratory pressure (ZEEP), Est,rs and EELV were similar in both groups of patients. The Est,L, however, was markedly higher in the ARDSp group than in the ARDSexp group (20.2 +/- 5.4 versus 13.8 +/- 5.0 cm H2O/L, p < 0.05), whereas Est,w was abnormally increased in the ARDSexp group (12.1 +/- 3.8 versus 5.2 +/- 1.9 cm H2O/L, p < 0.05). ⋯ Increasing PEEP to 15 cm H2O caused an increase of Est,rs in ARDSp (from 25.4 +/- 6.2 to 31.2 +/- 11.3 cm H2O/L, p < 0.01) and a decrease in ARDSexp (from 25.9 +/- 5.4 to 21.4 +/- 55.5 cm H2O/L, p < 0.01). The estimated recruitment at 15 cm H2O PEEP was -0.031 +/- 0.092 versus 0.293 +/- 0.241 L in ARDSp and ARDSexp, respectively (p < 0.01). The different respiratory mechanics and response to PEEP observed are consistent with a prevalence of consolidation in ARDSp as opposed to prevalent edema and alveolar collapse in ARDSexp.
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Am. J. Respir. Crit. Care Med. · Jul 1998
Inhaled corticosteroids and the prevention of readmission to hospital for asthma.
Despite the proven efficacy of inhaled corticosteroids in reducing airway inflammation and their increasing use for the treatment of asthma since the mid 1980s, hospitalization for asthma has been increasing in frequency in several countries. Only few studies, reporting contradictory results, have investigated the role of inhaled corticosteroids in the prevention of hospitalizations for asthma. Using a cohort of 2,059 hospitalized asthmatic patients between 5 and 54 yr of age, we estimated the effectiveness of inhaled corticosteroids in preventing a readmission to hospital for asthma as a function of the duration of therapy. ⋯ Subjects treated regularly with inhaled corticosteroids for at least 16 d and as long as 6 mo were 40% less likely to be readmitted for asthma (RR = 0.6; 95% CI: 0.4-0.9), while after 6 mo of regular treatment the protective effect disappeared (RR = 1.3; 95% CI: 0.7-2.4). We conclude that regular therapy with inhaled corticosteroids can substantially reduce the risk of a readmission for asthma after only 15 d of use. Confounding by severity appears as the most likely explanation for the disappearance of the beneficial effect after 6 mo of regular therapy.
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Am. J. Respir. Crit. Care Med. · Jul 1998
Involvement of tachykinin NK3 receptors in citric acid-induced cough and bronchial responses in guinea pigs.
Aerosolized citric acid induces several pulmonary effects including bronchoconstriction, airway inflammation, and cough. Evidence from the use of tachykinin NK1 and NK2 receptor antagonists, as well as chronic treatment with high doses of capsaicin, have suggested that these effects are mediated through the release of tachykinins from sensory nerve endings. In the present study, we have investigated the effects of a tachykinin NK3 receptor antagonist, SR 142801 (osanetant), on cough, bronchoconstriction, and bronchial hyperresponsiveness induced by aerosolized citric acid (0.4 M) in guinea pigs. ⋯ A microvascular leakage hypersensitivity also occurred and was demonstrated by a potentiation of the plasma protein extravasation from bronchial vessels induced by histamine. When given once intraperitoneally at 1 mg . kg-1 30 min before the citric acid exposure, SR 142801 inhibited both hyperresponsiveness to acetylcholine and the potentiation of histamine-induced increase in microvascular permeability. The results suggest that tachykinin NK3 receptors are involved in citric acid-induced effects on airways.
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Am. J. Respir. Crit. Care Med. · Jul 1998
Analysis of HLA-DPB1 polymorphisms in African-Americans with sarcoidosis.
Several studies have found weak associations between certain human leukocyte antigen (HLA) alleles and sarcoidosis, but none have been conclusive. Glutamic acid at position 69 in HLA-DPB1 has been reported to be strongly associated with chronic beryllium disease. ⋯ Results indicate that Val36 (odds ratio [OR] = 2.30) and Asp55 (OR = 2.03) are associated with increased risk for sarcoidosis, but no association with Glu69 was found. These results suggest that although HLA-DPB1 Glu69 is not associated with sarcoidosis, other alleles may make some contribution to susceptibility to sarcoidosis in African-Americans.