Critical care medicine
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Critical care medicine · May 1996
End-tidal carbon dioxide during cardiopulmonary resuscitation in humans presenting mostly with asystole: a predictor of outcome.
To determine whether continuous semiquantitative assessment of end-tidal CO2 could provide a highly sensitive predictor of return of spontaneous circulation during cardiopulmonary resuscitation (CPR). ⋯ End-tidal CO2 represents a valuable tool for monitoring patients presenting with asystole during prehospital CPR. Fluctuations in end-tidal CO2 during CPR and the utility of end-tidal CO2 in detecting return of spontaneous circulation justify its continuous measurement. In addition, a high sensitivity (>90%) in predicting return of spontaneous circulation is prospectively demonstrated using the maximal end-tidal CO2 during the first 20 mins after tracheal intubation, with a cutoff value of 10 torr. Such a prognostic indicator could be used for a more rational approach to prolonged CPR.
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Critical care medicine · May 1996
Accuracy and reliability of disposable pressure transducers coupled with modern pressure monitors.
To determine the bedside accuracy of direct patient pressure monitoring when used with new and clinically used disposable blood pressure (BP) transducers. ⋯ All disposable BP transducers tested were much more accurate than the American National Standards Institute standard for accuracy. Even the worst case transducers were twice as accurate as required by the American National Standards Institute standard. Only one bedside monitor was outside the +/- 2% accuracy range (103 mm Hg). Based on these findings, this author recommends that fixed calibration disposable transducers and fixed calibration bedside pressure monitoring systems be used. The clinical risks of air embolism and infection from the calibrating mercury manometer and the complexity of the calibration task are the overriding factors for making these recommendations.
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Critical care medicine · May 1996
Evaluation of the effects of autotransfusion of unprocessed blood on hemodynamics and oxygen transport in anesthetized pigs.
To examine the hemodynamic effects and the oxygen transport pattern of autotransfusion of unprocessed blood on hemodynamics and oxygen transportation. ⋯ Reinfusion of large amounts of unprocessed blood (up to 40% of blood volume), collected with compresses from a noncontaminated surgical field is a cheap method, which may be of potential benefit in trauma patients, when more sophisticated autotransfusion devices are lacking. In the present study, this method resulted in transient but significant hemodynamic changes in the pulmonary circulation. Impairment of oxygen transport was noticed after the end of hemorrhage, but this impairment cannot be attributed to the autotransfusion technique alone, but also to factors such as hemorrhagic shock, surgical trauma, etc.
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Critical care medicine · May 1996
Comparative StudyInspired oxygen concentration alters the phospholipids and protein content in the bronchoalveolar lavage-accessible space.
To examine the effect of FIO2 on the contents of total protein, total phospholipids, phosphatidylcholine, and phosphatidylglycerol in the bronchoalveolar lavage-accessible space in male and female rats in vivo. ⋯ Our findings support the hypothesis that hyperoxia alters surfactant composition. Further investigation is warranted to determine the mechanisms affecting secretion of phosphatidylcholine and phosphatidylglycerol into the bronchoalveolar space and to explore the gender difference in secretion.
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Critical care medicine · May 1996
Correction of blood pH attenuates changes in hemodynamics and organ blood flow during permissive hypercapnia.
To determine whether changes in cardiac output, regional blood flow, and intracranial pressure during permissive hypercapnia are blood pH-dependent and can be attenuated by correction of intravascular acidemia. ⋯ Acute hypercapnia, induced within 1 hr, is associated with significant increases in cardiac output, organ blood flow, and intracranial pressure. These changes can be significantly attenuated by correction of blood pH with the administration of sodium bicarbonate, without adverse effects on hemodynamics.