Critical care : the official journal of the Critical Care Forum
-
Metabolic alkalosis is a commonly encountered acid-base derangement in the intensive care unit. Treatment with the carbonic anhydrase inhibitor acetazolamide is indicated in selected cases. According to the quantitative approach described by Stewart, correction of serum pH due to carbonic anhydrase inhibition in the proximal tubule cannot be explained by excretion of bicarbonate. Using the Stewart approach, we studied the mechanism of action of acetazolamide in critically ill patients with a metabolic alkalosis. ⋯ A single dose of acetazolamide effectively corrects metabolic alkalosis in critically ill patients by decreasing the serum SID. This effect is completely explained by the increased renal excretion ratio of sodium to chloride, resulting in an increase in serum chloride.
-
Comparative Study
Lactate versus non-lactate metabolic acidosis: a retrospective outcome evaluation of critically ill patients.
Acid-base abnormalities are common in the intensive care unit (ICU). Differences in outcome exist between respiratory and metabolic acidosis in similar pH ranges. Some forms of metabolic acidosis (for example, lactate) seem to have worse outcomes than others (for example, chloride). The relative incidence of each type of disorder is unknown. We therefore designed this study to determine the nature and clinical significance of metabolic acidosis in critically ill patients. ⋯ In critically ill patients in which a measurement of lactate level was ordered, lactate and SIG were strong independent predictors of mortality when they were the major source of metabolic acidosis. Overall, patients with metabolic acidosis were nearly twice as likely to die as patients without metabolic acidosis.
-
Traditional teaching suggests that corticosteroids should be avoided during acute infectious episodes for fear of compromising the immune response. However, the outcome benefit shown through steroid administration in early septic shock implies this paranoia may be misplaced. We therefore performed a systematic review of the literature to identify the current strength of evidence for the use of corticosteroids in specified infections, and to make appropriate graded recommendations.
-
Changes in hemodynamic monitoring over the past 10 years have followed two paths. First, there has been a progressive decrease in invasive monitoring, most notably a reduction in the use of the pulmonary artery catheter because of a presumed lack of efficacy in its use in the management of critically ill patients, with an increased use of less invasive monitoring requiring only central venous and arterial catheterization to derive the same data. Second, numerous clinical trials have documented improved outcome and decreased costs when early goal-directed protocolized therapies are used in appropriate patient populations, such as patients with septic shock presenting to Emergency Departments and high-risk surgical patients before surgery (pre-optimization) and immediately after surgery (post-optimization). Novel monitoring will be driven more by its role in improving outcomes than in the technical abilities of the manufacturers.
-
During the past decade, critical care in the out-of-hospital setting has transcended the original emphasis on on-scene advanced life support interventions by doctors, paramedics, and nurses. Many of the life-saving efforts and advances in critical care situations have now begun to focus more and more on how, through evolving technology, the average person can save lives and perhaps even spare precious intensive care unit (ICU) resources. A striking example was the recent study conducted at the Chicago airports at which automated external defibrillators (AEDs) were deployed throughout the airline terminals for use by the public at large. ⋯ Thus, this technology-assisted intervention, performed by an average person, pre-empted the need for many other critical care interventions and prolonged care in the ICU. Equipped with automated prompts to improve performance, new technology also exists to help to monitor the inadequacies and too-frequent interruption of life-saving chest compressions during basic cardiopulmonary resuscitation. As a result of these technological advances, survival rates for cardiac arrest are now expected to improve significantly.