American journal of respiratory and critical care medicine
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Am. J. Respir. Crit. Care Med. · Jul 2000
Relation between respiratory changes in arterial pulse pressure and fluid responsiveness in septic patients with acute circulatory failure.
In mechanically ventilated patients with acute circulatory failure related to sepsis, we investigated whether the respiratory changes in arterial pressure could be related to the effects of volume expansion (VE) on cardiac index (CI). Forty patients instrumented with indwelling systemic and pulmonary artery catheters were studied before and after VE. Maximal and minimal values of pulse pressure (Pp(max) and Pp(min)) and systolic pressure (Ps(max) and Ps(min)) were determined over one respiratory cycle. ⋯ VE-induced changes in CI closely correlated with DeltaPp before volume expansion (r(2) = 0. 85, p < 0.001). VE decreased DeltaPp from 14 +/- 10 to 7 +/- 5% (p < 0.001) and VE-induced changes in DeltaPp correlated with VE-induced changes in CI (r(2) = 0.72, p < 0.001). It was concluded that in mechanically ventilated patients with acute circulatory failure related to sepsis, analysis of DeltaPp is a simple method for predicting and assessing the hemodynamic effects of VE, and that DeltaPp is a more reliable indicator of fluid responsiveness than DeltaPs.
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Am. J. Respir. Crit. Care Med. · Jul 2000
Glucocorticoid receptor alpha and beta in glucocorticoid dependent asthma.
Patients with glucocorticoid (GC)-dependent asthma present an ongoing inflammation of the airways despite chronic long-term treatment with oral GC. Interleukin (IL)-8 and granulocyte/macrophage colony-stimulating factor (GM-CSF) have been implicated in airway inflammation in severe asthma and their synthesis is normally repressed by GC. To further characterize the inflammatory process in GC-dependent asthma, we measured the release of IL-8 and GM-CSF by peripheral blood mononuclear cells (PBMC) of eight normal subjects, six untreated controlled asthmatics, six untreated uncontrolled asthmatics, and nine GC-dependent asthmatics. ⋯ GRalpha and GRbeta are, respectively, the functional receptor and a putative dominant negative form of the receptor. Western blot and polymerase chain reaction (PCR) analyses indicated that GRalpha was expressed at similar level in all groups and was largely predominant over GRbeta. Thus, persistent release of IL-8 and GM-CSF in GC-dependent asthma is not associated with low expression of GRalpha or overexpression of GRbeta.
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Am. J. Respir. Crit. Care Med. · Jul 2000
Case ReportsTreatment of nosocomial pneumonia and tracheobronchitis caused by multidrug-resistant Pseudomonas aeruginosa with aerosolized colistin.
Gram-negative bacilli including multidrug-resistant (MDR) Pseudomonas aeruginosa are responsible for a significant proportion of episodes of nosocomial pneumonia. Since the development of new antibiotics with activity against gram-negative organisms has not kept pace with the increase in prevalence of MDR pathogens, there has been renewed interest in antimicrobial agents that had previously been used but had been abandoned because of toxic side effects. This report describes three patients with nosocomial pneumonia or tracheobronchitis due to multiresistant strains of P. aeruginosa for whom aerosolized colistin proved beneficial as supplemental therapy. Aerosolized colistin merits further consideration as a therapeutic intervention for patients with pulmonary infections due to MDR P. aeruginosa.
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Am. J. Respir. Crit. Care Med. · Jul 2000
Selective NOS inhibition restores myocardial contractility in endotoxemic rats; however, myocardial NO content does not correlate with myocardial dysfunction.
The role of nitric oxide (NO) in lipopolysaccharide (LPS)-induced myocardial dysfunction remains controversial as some investigators concluded that inhibition of NO synthesis improves left ventricular (LV) contractility, whereas others did not. We investigated the relationship between LPS-induced LV dysfunction and LV NO production. We postulated that high myocardial NO concentrations would correspond to decreased contractility and low NO concentrations would correspond to recovery. ⋯ Myocardial NO content in the SMT was lower than that of the LPS only group, but higher than the L-NAME group. We conclude that SMT is beneficial to myocardial contractility in this model of endotoxemia, whereas pretreatment with L-NAME is associated with further deterioration of contractility and increased mortality. Moreover, our data indicate that high myocardial NO concentrations do not necessarily correlate with decreased contractility.