Critical care medicine
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Critical care medicine · May 1991
Unaccounted for anion in metabolic acidosis during severe sepsis in humans.
To quantitate the contribution of lactate, phosphate, urate, total serum proteins, and unidentified anions to the anion gap in patients with severe sepsis. ⋯ These data indicate that lactic acidosis does not entirely account for the metabolic acidosis during severe sepsis. Furthermore, the increased corrected anion gap suggests the presence of an unidentified anion (or anions) that is (or are) responsible, in large part, for the development of metabolic acidosis in patients with sepsis.
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Critical care medicine · May 1991
Comparative StudyOxygen transport measurements to evaluate tissue perfusion and titrate therapy: dobutamine and dopamine effects.
Increased cardiac index, oxygen delivery (DO2), and oxygen consumption (VO2) patterns were shown to characterize the physiologic status of surviving high-risk surgical patients, and indicate increased metabolic needs; relatively normal DO2 and VO2 values were found to characterize the sequential pattern of nonsurvivors who developed an early oxygen debt followed by lethal organ failure. The cardiac index, DO2, and VO2 values empirically determined from survivors' patterns were shown to improve outcome in prospective randomized trials. The present study considers these criteria to evaluate the tissue perfusion status as well as the effects of therapy on tissue perfusion and oxygenation. ⋯ The monitored patterns of cardiac index, DO2, and VO2 may be used to evaluate the adequacy of tissue perfusion as well as the relative effectiveness of alternative therapies. Second, these physiologic criteria may be used to titrate therapy in order to achieve optimal outcome. Third, after colloids optimally expand the plasma volume, dobutamine may be used to enhance flow and the distribution of flow in order to improve tissue oxygenation. Vasodilators may be used when hypertensive episodes occur or there is an inadequate response to inotropic agents. Vasopressors are used as a last resort, usually in the terminal or preterminal state.
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This review article examines the pathophysiology of septic shock, with special attention to the concept of supply-dependent consumption and the implications this concept has for therapy. Patients with septic shock require higher levels of oxygen delivery (DO2) to maintain aerobic metabolism. When DO2 is inadequate, peripheral tissues switch to anaerobic metabolism and oxygen consumption decreases. ⋯ Maximizing DO2 is an important part of the hemodynamic resuscitation of patients with septic shock. To achieve this goal, intravascular volume must be restored and the myocardial depression associated with sepsis must be treated to optimize cardiac output. The normalization of arterial lactate concentration is a reasonable goal of resuscitative efforts.
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Critical care medicine · May 1991
Cardiovascular adjustments and gas exchange during extreme hemodilution in humans.
To examine the cardiovascular adjustments and pattern of gas exchange that occur during hemodilution. ⋯ The data suggest that, during hemodilution, tissue autoregulation of VO2 and utilization are not impaired, but gas exchange function (Qsp/Qt) is impaired.