Critical care : the official journal of the Critical Care Forum
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Comparative Study
Initial distribution volume of glucose can be approximated using a conventional glucose analyzer in the intensive care unit.
We previously reported that initial distribution volume of glucose (IDVG) reflects central extracellular fluid volume, and that IDVG may represent an indirect measure of cardiac preload that is independent of the plasma glucose values present before glucose injection or infusion of insulin and/or vasoactive drugs. The original IDVG measurement requires an accurate glucose analyzer and repeated arterial blood sampling over a period of 7 min after glucose injection. The purpose of the present study was to compare approximated IDVG, derived from just two blood samples, versus original IDVG, and to test whether approximated IDVG is an acceptable alternative measure of IDVG in the intensive care unit. ⋯ Our findings demonstrate that there was good correlation between each approximated IDVG and original IDVG, although the two measures are not interchangeable. This suggests that approximated IDVG is clinically acceptable as an alternative calculation of IDVG, although approximated and original IDVGs are not equivalent; plasma rather than whole blood measurements are preferable.
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The use of a nursing-directed and/or respiratory therapist-directed protocol in many intensive care units for weaning from mechanical ventilation is associated with a shorter duration of ventilation and length of stay in the ICU. Most protocols have two formal components: the daily screening of a set of simple observations or interventions to identify readiness to proceed, followed by a spontaneous breathing trial that tests the patient's ability to breathe independently. The daily screen is designed to identify potential barriers regarding medical stability, level of consciousness, oxygenation, ventilation, and airway patency and protection. However, one must avoid selecting criteria that are too restrictive, potentially delaying the discontinuation of ventilation.
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Comment Comparative Study
Extracorporeal therapies in acute rhabdomyolysis and myoglobin clearance.
Rhabdomyolysis is a pathogenetic cause of acute kidney injury. In such circumstances, not only should therapeutic strategies to replace the failing kidney be implemented, but measures should also be explored to prevent further damage by circulating myoglobin. Volume expansion and forced diuresis have been used, but when a kidney fails, renal replacement therapies are instituted. ⋯ The removal of myoglobin was greater than in than any previous report. Thus, if the removal of myoglobin is desirable, a combination of continuous hemofiltration and hyperpermeable membranes seems to be the most effective. However, care must be exercised to prevent unwanted albumin losses.
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Comparative Study
Increased blood flow prevents intramucosal acidosis in sheep endotoxemia: a controlled study.
Increased intramucosal-arterial carbon dioxide tension (PCO2) difference (DeltaPCO2) is common in experimental endotoxemia. However, its meaning remains controversial because it has been ascribed to hypoperfusion of intestinal villi or to cytopathic hypoxia. Our hypothesis was that increased blood flow could prevent the increase in DeltaPCO2. ⋯ In this model of endotoxemia, intramucosal acidosis was corrected by increased blood flow and so might follow tissue hypoperfusion. In contrast, anion-gap metabolic acidosis was left uncorrected and even worsened with aggressive volume expansion. These results point to different mechanisms generating both alterations.
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Impaired health-related quality of life after critical illness has been demonstrated in a number of studies. It is not clear exactly how or why critical illness and intensive care lead to impaired health status, but understanding this association is an important step to improving long-term outcomes of the critically ill. ⋯ This commentary examines a recent study and places this study in the context of previous studies suggesting that both amnesia and persisting nightmares of the ICU experience are associated with impaired quality of life. Further research is needed if we are effectively to understand, prevent and treat the negative sequelae of critical illness.