Critical care medicine
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Critical care medicine · Apr 1996
Comparative StudyEffect of conventional mechanical ventilation and jet ventilation on airway pressure in dogs and plastic models with tracheal stenosis.
To evaluate the effect of jet ventilation on tracheal stenosis in dogs and plastic models. ⋯ The jet flow that struck the portion of the stenosed wall reversed direction, even during early expiration. Therefore, the expiration during jet ventilation was facilitated more by the reversed flow than by the expiration during conventional mechanical ventilation. This reversed flow may provide lower end-expiratory airway pressure at the poststenotic portion with jet ventilation than with conventional mechanical ventilation. We conclude that jet ventilation was a useful method of ventilation in cases with tracheal stenosis, especially nonfluid and short stenosis.
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Critical care medicine · Apr 1996
Meta AnalysisAdult respiratory distress syndrome: a systemic overview of incidence and risk factors.
To determine the published incidence of adult respiratory distress syndrome (ARDS) as well as the clinical evidence supporting a casual association between ARDS and its major risk factors. ⋯ The significant variation in the incidence of ARDS is attributed to differences in the type and strength of study designs, as well as definitions or ARDS. While a substantial body of evidence exists concerning a casual role of ARDS risk factors, such as sepsis, aspiration, and trauma, > 60% of clinical studies employed weak designs. The lack of reproducible definitions for ARDS or its potential risk factors in 49% of studies raises concerns about the validity of the conclusions of these studies regarding the association between ARDS and the supposed risk factors.
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Critical care medicine · Apr 1996
Randomized Controlled Trial Comparative Study Clinical TrialModulating effects of propofol on metabolic and cardiopulmonary responses to stressful intensive care unit procedures.
Patients in the intensive care unit (ICU) undergo acute increases in metabolic and cardiopulmonary demands in response to routine care interventions, such as chest physical therapy. This study examined whether the short-acting drug, propofol, could blunt the responses to chest physical therapy. ⋯ Propofol, in the doses administered in this study, significantly reduced the hemodynamic and metabolic stresses caused by chest physical therapy.
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Critical care medicine · Apr 1996
Comparative StudyPrediction of outcome in patients with anoxic coma: a clinical and electrophysiologic study.
To evaluate and compare the predictive powers of clinical examination, electroencephalography (EEG), and studies of short-latency somatosensory evoked potentials in determining the prognosis in anoxic coma. ⋯ Based on the present data and a literature review, we propose that clinical examination combined with the results of EEG and somatosensory evoked potentials can be used to establish an early, definitive prognosis in a significant proportion of patients in anoxic coma. On day 3 or thereafter, patients with motor response of extension to pain or worse and malignant EEG, or those patients with flexor posturing or worse and bilaterally absent cortical somatosensory evoked potentials invariably have poor outcome. However, some patients with initially malignant EEG and normal somatosensory evoked potentials may recover and should be supported until their prognoses become more definitive.
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Critical care medicine · Apr 1996
Comparative StudyRegional blood flow alterations after bovine fumaryl beta beta-crosslinked hemoglobin transfusion and nitric oxide synthase inhibition.
a) To determine whether isovolemic exchange transfusion with cell-free, bovine fumaryl beta beta-crosslinked hemoglobin results in a different pattern of regional blood flow distribution than transfusion with a poor oxygen-carrying, colloidal solution. b) Because of potential nitric oxide scavenging by plasma-based hemoglobin, to determine whether blood flow differences are reduced after nitric oxide synthase inhibition. ⋯ Transfusion with cell-free, bovine crosslinked hemoglobin in cats can selective reductions in blood flow in the intestines, kidneys, and adrenal glands without evidence of renal dysfunction by a mechanism consistent with nitric oxide scavenging. In skeletal and cardiac muscle, the increase in blood flow persisted after nitric oxide inhibition in the albumin group relative to the hemoglobin-transfused group at equivalent hematocrit values. This finding is consistent with compensatory vasoconstriction with hemoglobin transfusion due to improved oxygenation by this oxygen carrier.