Chest
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Clinical Trial
Is tracheal gas insufflation an alternative to extrapulmonary gas exchangers in severe ARDS?
Tracheal gas insufflation (TGI) of pure oxygen combined with mechanical ventilation decreases dead space and increases CO2 clearance. In the present study, TGI was used in six patients with ARDS who met extracorporeal membrane oxygenation criteria and who were severely hypoxemic and hypercapnic despite optimal pressure-controlled ventilation. This open clinical study aimed to investigate the effects of 4 L/min continuous flow of oxygen given via an intratracheal catheter. ⋯ There was no change in airway pressures and hemodynamic variables. A slight increase in end-expiratory and end-inspiratory volumes with TGI possibly occurred, as seen on tracings from respiratory inductive plethysmography (Respitrace). We conclude that TGI improves tolerance of limited pressure ventilation by removing CO2, but it may induce changes in lung volumes that are not detected by ventilator measurements.
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We undertook the present study with the following objectives: (1) to compare the difference between the end-tidal and the arterial carbondioxide concentration (P[ETa] CO2) gradients at rest and during exercise in normal subjects and patients with COPD; and (2) to analyze the factors contributing to this gradient. We studied seven normal subjects and seven patients with COPD using a symptom-limited exercise test on a cycle ergometer. Our results show that the P(ET-a)CO2 increased progressively as the individuals went from rest to higher workloads in both the normal group and in the COPD group. ⋯ The PaCO2 in normal subjects and in the COPD group correlated significantly with the partial pressure of end-tidal carbon dioxide (PETCO2). Using multiple regression analysis, with the PaCO2 as the dependent variable and the PETCO2 (along with other physiologic measures) as the independent variables, we found that the standard error of the estimate was still above 2.1 mm Hg in normal subjects and in patients with COPD. We conclude that (1) during exercise, the P(ET-a)CO2 in normal subjects and in patients with COPD increases significantly, (2) the P(ET-a)CO2 gradient is more closely correlated with the VD/VT than any other physiologic variable, and (3) changes in the PETCO2 during exercise are not correlated closely with changes in the PaCO2.
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Multicenter Study Clinical Trial Controlled Clinical Trial
Clarithromycin in the treatment of Mycobacterium avium lung infections in patients without AIDS. Clarithromycin Study Group of France.
Mycobacterium avium complex infections, common in patients with AIDS as either pulmonary or disseminated disease, are infrequent in patients without AIDS. Participants were 45 HIV-negative patients with lung disease and positive sputum cultures for M avium; 10 had documented immunocompromise, and 24 had preexisting lung disease. Clarithromycin dosage was 500 to 2,000 mg daily (mean +/- SD = 1,633 +/- 432 mg). ⋯ During the follow-up, one patient suffered a relapse with peripheral lymph nodes. A daily dose of 30 mg/kg of clarithromycin in the treatment of M avium infections appears to be effective and safe. Concomitant drug therapy should be assessed for its ability to prevent relapse.
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Randomized Controlled Trial Clinical Trial
The effect of short-term instillation of a mucolytic agent (mesna) on airway resistance in mechanically ventilated patients.
To determine whether bolus instillation of a mucolytic agent (mesna) could diminish airway resistance, endotracheal tube resistance, or both in patients mechanically ventilated for acute respiratory failure. ⋯ In our patients, bolus tracheal instillation of mesna does not improve airway resistance; in fact, mesna instillation induces episodes of bronchospasm that disappear 2 h later.