Chest
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It is maintained that pulmonary angiography is required for confirmation or exclusion of pulmonary embolism in the majority of patients suspected of having pulmonary embolism. The aim of this study was to reappraise the role of perfusion scan in conjunction with clinical assessment in the diagnosis of pulmonary embolism and to identify subsets of patients in whom angiography is strictly required for definitive diagnosis. At the time of referral, each of 252 consecutive patients was assigned a clinical probability of pulmonary embolism (very likely, possible, unlikely). ⋯ Sensitivity and specificity of PE+ perfusion scan were 89 and 92%, respectively. Pulmonary embolism was present in all 37 patients with very likely or possible clinical presentation and PE+ scan (positive predictive value 100%) and in 2 of 17 cases with low likelihood of pulmonary embolism and PE- scan (negative predictive value of 88%). These preliminary results indicate that pulmonary embolism can be diagnosed noninvasively in the majority of cases and that angiography is strictly required only for a minority of patients (21% in this study) in whom clinical and perfusion scan assessment are discordant.
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To describe the hemodynamic and oxygen transport patterns in survivors and nonsurvivors following liver transplantation (LT) and to assess their relationship to organ failure and mortality. ⋯ Nonsurvivors of LT have less cardiac reserve pretransplant; postoperatively, they demonstrate early myocardial depression and subsequently lower levels of cardiac index and oxygen delivery. Patients who develop these hemodynamic patterns are more prone to organ failure and death.
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Recently we showed that work of breathing was higher in the immediate period after extubation as compared with spontaneous breathing through an endotracheal tube. In this study, we evaluated the glottis and trachea as potential sites of increased airway resistance after extubation. We measured breathing pattern, work of breathing, and pressure time product in eight patients during weaning from mechanical ventilation. ⋯ This value was larger than the mean cross-sectional area of the endotracheal tubes used in these patients (50 mm2). We conclude that neither tracheal nor laryngeal disease caused the increase in work of breathing after extubation. Our data suggest that upper airway narrowing at a more proximal site, such as the oropharynx or velopharynx may be the cause of the increase in respiratory work.
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Independent lung ventilation using two ventilators has been attempted in the treatment of acute respiratory failure due to unilateral lung disease. However, this method has been found to be cumbersome and difficult to use. We reasoned that a bifurcated endotracheal tube with a variable resistance valve may enable us to change the inspiratory airway pressures and, hence, the inspired tidal volume to one lung using a single ventilator. ⋯ With a ventilator-generated peak inspiratory pressure of 31 +/- 2 cm H2O, the airway pressure distal to the valve was randomly changed from 31 cm H2O to 23 +/- 2, 15 +/- 1, 8 +/- 1, and 0 cm H2O. This resulted in progressive diversion of tidal volume from the experimental lung to the control lung and an increase in exhaled tidal volume due to a decrease in air leak from the bronchopleural fistula. These data suggest that a variable resistance valve may be used for independent lung ventilation using a single ventilator.
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Case Reports
Reversal of 'refractory septic shock' by infusion of amrinone and angiotensin II in an anthracycline-treated patient.
A 53-year-old granulocytopenic woman with malignant lymphoma treated with cyclophosphamide, doxorubicin, vincristine, and prednisone (CHOP) chemotherapy, including doxorubicin (Adriamycin) and autologues bone marrow transplantation, presented in the clinical state of "refractory septic shock" caused by Escherichia coli. Despite inotropic treatment with dopamine, dobutamine, and norepinephrine infusion, the patient's condition did not improve, but during treatment with amrinone and angiotensin II infusion, the septic shock was reversed. The patient was monitored with a pulmonary artery catheter and underwent repeated echocardiographic examinations. ⋯ Apparently these beta-receptors were bypassed via the enzymatic action of amrinone upon cyclic monoadenosine phosphate. This is, to our knowledge, the first doxorubicin-treated patient with septic shock refractory to conventional vasopressor therapy whose condition reversed by inotropic treatment with amrinone and angiotensin II. This treatment may prove to be an alternative choice for patients developing "refractory septic shock" unresponsive to treatment with norepinephrine, dobutamine, and dopamine.