Other bulletins in this series include:

Breast Surgery

Thursday, 3 March 2011

Delirium in the ICU: time to probe the hard questions

Delirium in the ICU: time to probe the hard questions. Critical Care 2011 15:118

Stevens, R.D., et al.

Prevalent in critically ill patients, delirium remains poorly understood and difficult to treat. In a cross-sectional study conducted in 12 countries, delirium was identified in close to one third of patients and was independently associated with increased mortality. While such epidemiological accounts represent an important cornerstone for research, scientific efforts are needed to elucidate the causes of delirium and the mechanisms underlying its association with poor outcomes.

Sizing the lung of mechanically ventilated patients

Sizing the lung of mechanically ventilated patients. Critical Care 2011, 15:R60

Mattingley, J.S., et al

http://ccforum.com/content/15/1/R60

This small observational study was motivated by our belief that scaling the tidal volume in mechanically ventilated patients to the size of the injured lung is safer and more "physiologic" than scaling it to predicted body weight, i.e. its size before it was injured. We defined Total Lung Capacity (TLC) as the thoracic gas volume at an airway pressure of 40 cm H2O and tested if TLC could be inferred from the volume of gas that enters the lungs during a brief "recruitment" maneuver.

Blood purification for sepsis

Blood purification for sepsis. Critical Care 2011 15:205.

Kellum, J.

Sepsis is the primary cause of death in the intensive care unit. Extracorporeal blood purification therapies have been proposed for patients with sepsis in order to improve outcomes since these therapies can alter the host inflammatory response by non-selective removal of inflammatory mediators and/or bacterial products. Recent technological progress has increased the number of techniques available for blood purification and their performance.In this overview, we report on the latest advances in blood purification for sepsis, how they relate to current concepts of disease, and we review the current evidence for high-volume hemofiltration, cascade hemofiltration, hemoadsorption, coupled plasma filtration adsorption, high-adsorption hemofiltration and high cut-off hemofiltration/hemodialysis. Promising results have been reported with all these blood purification therapies showing that they are well tolerated, effective in clearing inflammatory mediators and/or bacterial toxins from the plasma and efficacious for improvement various physiologic outcomes (e.g. hemodynamics, oxygenation). However, numerous questions remain unanswered including the timing, duration and frequency of these therapies in the clinical setting. Large multicenter trials evaluating the ability of these therapies to improve clinical outcomes (i.e. mortality or organ failure), rather than surrogate markers such as plasma mediator clearance or transient improvement in physiologic variables, are required to define the precise role of blood purification in the management of sepsis.

Immunity, inflammation and sepsis: new insights and persistent questions

Immunity, inflammation and sepsis: new insights and persistent questions.
Critical Care 2011 15:124

Frazier, W.J.

Sepsis is now understood to affect a variety of changes in the host, chief among them being alterations in immune system function. Proper immune function involves a competent proinflammatory response to stimuli as well as a regulated counteracting force to restore homeostasis and prevent systemic inflammation and organ dysfunction. Broad-spectrum suppression of the inflammatory response has not been shown to be beneficial to patients suffering from septic disease. In fact, sepsis-related immune suppression has become increasingly recognized as an important contributor to late morbidity and mortality in the critically ill. Giamarellos-Bourboulis and colleagues detail the impaired ability of septic patients to produce proinflammatory cytokines upon ex-vivo stimulation, and introduce altered caspase-1activity as potentially contributory to this process. Proper understanding of the cellular and molecular events resulting in immune suppression following sepsis are important in the identification of new strategies for treatment and the ideal timing of therapy.