Critical care : the official journal of the Critical Care Forum
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The benefit of albumin administration in the critically ill patient is unproven. Epidemiological evidence suggests that there is an increase in death among patients with burns, hypoalbuminaemia, and hypotension treated with human albumin solution (HAS). ⋯ When treating patients with hypoalbuminaemia, efforts must be centred around correction of the underlying disorder rather than reversal of hypoalbuminaemia. Problems with using albumin arise because it is an expensive blood product, and can result in systemic changes that include cardiovascular, haematological, renal, pulmonary, and immunological effects.
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According to the Frank-Starling relationship, a patient is a 'responder' to volume expansion only if both ventricles are preload dependent. Mechanical ventilation induces cyclic changes in left ventricular (LV) stroke volume, which are mainly related to the expiratory decrease in LV preload due to the inspiratory decrease in right ventricular (RV) filling and ejection. In the present review, we detail the mechanisms by which mechanical ventilation should result in greater cyclic changes in LV stroke volume when both ventricles are 'preload dependent'. We also address recent clinical data demonstrating that respiratory changes in arterial pulse (or systolic) pressure and in Doppler aortic velocity (as surrogates of respiratory changes in LV stroke volume) can be used to detect biventricular preload dependence, and hence fluid responsiveness in critically ill patients.
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Our current state of knowledge on noninvasive positive pressure ventilation (NPPV) and technical aspects are discussed in the present review. In patients with chronic obstructive pulmonary disease, NPPV can be considered a valid therapeutic option to prevent endotracheal intubation. ⋯ The conventional use of NPPV in hypoxaemic acute respiratory failure still remains controversial, however. Large randomized studies are still needed before extensive clinical application in this condition.
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Hemofiltration as an adjunct to therapy for sepsis is now 10 years old. Despite early successes and significant theoretical advantages, the treatment remains experimental. ⋯ Clinical as well as technical difficulties remain important considerations to future studies. These issues are discussed and the brief history of hemofiltration in sepsis is reviewed.
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Recent meta-analyses have created uncertainties regarding the appropriate clinical role of colloid resuscitation fluids in critically ill patients and prompted changes in fluid management practice. Such changes may not be justified in view of methodological limitations inherent in the meta-analyses. Further research is nevertheless needed to resolve the questions raised concerning the relationship between choice of resuscitation fluid and patient outcome. ⋯ The results of the randomized animal studies, along with other preclinical data, could also be evaluated using accepted principles of 'critical appraisal' commonly applied to clinical trial results. This critical appraisal might, where appropriate, include meta-analysis of animal study findings. This alternative preclinical pathway to new product evaluation should be completed before the commencement of large-scale clinical trials.