Critical care medicine
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Critical care medicine · May 1999
Utility of deadspace and capnometry measurements in determination of surfactant efficacy in surfactant-depleted lungs.
To investigate if bronchoalveolar lavage leads to increased alveolar and physiologic deadspace or a deadspace/ tidal volume ratio and if surfactant replacement restores the lung to its prelavage condition. ⋯ Bronchoalveolar lavage elevates the alveolar and physiologic deadspace and the deadspace/tidal volume ratios and is combined with a fall in the arterial/alveolar PO2 ratio. Surfactant treatment improves the gas exchange but does not restore the lung to its prebronchoalveolar lavage condition, which indicates that the exogenous surfactant affects only partly the recruitment of the atelectatic areas.
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Critical care medicine · May 1999
Nosocomial infections in medical intensive care units in the United States. National Nosocomial Infections Surveillance System.
To describe the epidemiology of nosocomial infections in medical intensive care units (ICUs) in the United States. ⋯ The distribution of sites of infection in medical ICUs differed from that previously reported in NNIS ICU surveillance studies, largely as a result of anticipated low rates of surgical site infections. Primary bloodstream infections, pneumonia, and urinary tract infections associated with invasive devices made up the great majority of nosocomial infections. Coagulase-negative staphylococci were more frequently associated with primary bloodstream infections than reported from NNIS ICUs of all types in the 1980s, and enterococci were a more frequent isolate from bloodstream infections than S. aureus. Fungal urinary tract infections, often asymptomatic and associated with catheter use, were considerably more frequent than previously reported. Invasive device-associated infections were associated with specific pathogens. Although device-associated site-specific infection rates are currently our most useful rates for performing comparisons between ICUs, the considerable variation in these rates between ICUs indicates the need for further risk adjustment.
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Critical care medicine · May 1999
Salutary effects of ATP-MgCl2 on the depressed endothelium-dependent relaxation during hyperdynamic sepsis.
Studies have shown that endothelium-dependent relaxation (mediated by endothelium-derived nitric oxide) is depressed during the early, hyperdynamic stage of sepsis. Although it is known that ATP-MgCl2 produces beneficial effects following various adverse circulatory conditions, it remains unknown whether this agent attenuates the depressed endothelium-dependent relaxation during early sepsis. The aim of this study, therefore, was to determine whether or not the administration of ATP-MgCl2 early after the onset of sepsis improves or maintains endothelium-dependent relaxation. ⋯ Since administration of ATP-MgCl2 prevents the impaired vascular relaxation to the endothelium-dependent vasodilator ACh, this agent may be a useful adjunct for maintaining endothelial cell function during the hyperdynamic stage of sepsis.
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Critical care medicine · May 1999
Phase-related changes in right ventricular cardiac output under volume-controlled mechanical ventilation with positive end-expiratory pressure.
To examine determinants of right ventricular function throughout the ventilatory cycle under volume-controlled mechanical ventilation with various positive end-expiratory pressure (PEEP) stages. ⋯ Increases in PEEP during volume-controlled mechanical ventilation leads to respiration-phase-specific reduction of right ventricular cardiac output, with a significantly pronounced decrease during the inspiration phase. This decrease in cardiac output should be taken into particular consideration for patients with already critically reduced cardiac output.