Journal of critical care
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Journal of critical care · Sep 1993
Infusion of ultrafiltrate from endotoxemic pigs depresses myocardial performance in normal pigs.
We previously showed a beneficial effect of hemofiltration on hemodynamics of endotoxic shock pigs. To test the hypothesis that this effect of hemofiltration is caused by convective removal of factors that adversely affect hemodynamics during endotoxemia, we infused ultrafiltrate from endotoxic shock pigs into healthy pigs. Their hemodynamics were compared with those of pigs who were infused with ultrafiltrate from healthy pigs. ⋯ The decrease in cardiac output in group 1 was greater than in group 2 (3.3 +/- 0.2 L/min v 0.3 +/- 0.3 L/min, P < .02) and was due to a decrease in stroke volume. The decrease in right ventricular ejection fraction was also greater (0.15 +/- 0.02 v 0.01 +/- 0.00, P < .01). Systemic vascular resistance, right atrial pressure, right ventricular end-diastolic volume, pulmonary wedge pressure and heart rate did not differ between groups.(ABSTRACT TRUNCATED AT 250 WORDS)
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Emphasis in medical training is laid on therapeutic approaches that prolong life at all costs. This training is reinforced by current medical practices in the United States and by an ever-expanding medical technology, such that it becomes difficult, if not impossible, to "let the patient go." In response, individuals promote the "right-to-die" and euthanasia, so that patients may maintain their human dignity during the dying process. A more rational and nonpolarized approach to this issue would be to strive for the preservation of human function, not physiological function alone. ⋯ On this basis, therapies can be withheld and withdrawn when they no longer reflect these goals. Caution regarding potential abuses of this approach need to be raised, however, when considering care for the very vulnerable of society. In that regard, therapeutic goals directed at maintaining human function need to be developed in parallel with global societal values regarding quality of life issues.
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Journal of critical care · Jun 1993
Comparative StudyOrgan blood flow and distribution of cardiac output in dopexamine- or dobutamine-treated endotoxemic rats.
Endotoxemia causes a decrease of blood flow to most organs. If this could be prevented, chances of survival might improve. In endotoxemic rats, we studied the effect of a therapeutic infusion of dopexamine (dopaminergic, beta 2-adrenergic) on blood flow and percentage of the cardiac output distributed to heart, brain, hepatic artery, stomach, intestines, spleen, pancreas, kidneys, adrenals, diaphragm, skeletal muscle, and skin. ⋯ Dopexamine and dobutamine similarly improved cardiac output in endotoxemic rats. All organs benefitted to the same extent from the increased cardiac output. Therapeutic infusion of dopexamine during endotoxemia did not favor flow to any particular organ; redistribution of cardiac output changed little after administration of dopexamine, and its effects were not significantly different from those of dobutamine.
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Journal of critical care · Jun 1993
Comparative StudyPositive end-expiratory pressure increases capillary pressure relative to wedge pressure in the closed and open chest.
The pulmonary arterial wedge pressure is used as a measure of left atrial pressure and frequently as an estimate of pulmonary capillary pressure. The arterial occlusion concept has recently been used to derive a pressure that is thought to be more representative of capillary pressure (Pcap) than wedge pressure (Pw). The object of this study was to measure the arterial occlusion Pcap at different positive end-expiratory pressure (PEEP) levels and to compare it with Pw. ⋯ Increasing PEEP between 0 to 15 mm Hg caused a gradual decline in cardiac output in the closed and open chest conditions. Despite this decline, all three pressures (Pa, Pcap, and Pw) rose gradually in the closed chest. However, in the open chest, increasing PEEP from 0 to 4.7 mm Hg had no effect on the pressures, but between 4.7 and 13.4 mm Hg of PEEP, Pa and Pcap increased markedly with minimal change in Pw.(ABSTRACT TRUNCATED AT 250 WORDS)
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Journal of critical care · Jun 1993
Allocation of critical care resources: entitlements, responsibilities, and benefits.
Determination of allocation of limited critical care resources appears to be an inevitable development. Criteria proposed to assign such limited resources among patients are not defined. It has been argued that allocation of critical care resources could be based on the principals of patient entitlements to health care, responsibilities of the physician to the critically ill patient, and beneficence. However, based on an analysis of the philosophical tenants of the Hippocratic Oath, there is little to support the concept of "sin" taxes or patient triage on the basis of judgment on the moral merit of the patient.