Critical care : the official journal of the Critical Care Forum
-
Reade et al. studied 20 agitated intubated patients in a pilot open-label trial comparing the efficacy of dexmedetomidine versus haloperidol in facilitating extubation. While the study design had limitations, which are outlined by the authors themselves in the paper published in this issue of Critical Care, the study demonstrated an impressive reduction in time to extubation and length of stay. Dexmedetomidine is a promising sedative agent that acts via alpha2-receptors and has been shown to decrease prevalence and duration of delirium in mechanically ventilated patients. ⋯ Agitated delirious patients are at risk of immediate adverse events as well as prolonged respiratory support. All delirious patients are at risk of poor cognitive outcomes. Further research is needed into the pharmacological management of delirium, including the use of dexmedetomidine in the management of agitation and the clinical efficacy of haloperidol.
-
A recent observational study in a large cohort of critically ill patients confirms the association between hyperlactatemia and mortality. The mechanisms regulating the rates of lactate production and clearance in critical illness remain poorly understood. ⋯ Possible mechanisms include regional hypoperfusion, an inflammation-induced upregulation of the glycolitic flux, alterations in lactate-clearing mechanisms, and increases in the work of breathing. Understanding how these complex processes interact to produce elevations in lactate continues to be an important area of research.
-
Hydroxyethyl starch (HES) solutions are widely used for volume replacement therapy but are also known to compromise coagulation, impair renal function and increase long-term mortality. To test the hypotheses that HES 130/0.4 has fewer adverse effects than HES 200/0.5 and exerts anti-inflammatory properties, we compared the effects of HES 130/0.4, HES 200/0.5 and saline on in vitro haemostasis and pro-inflammatory platelet function. ⋯ Our data demonstrate that HES 130/0.4 has similar adverse effects as HES 200/0.5. In particular, both types of HES impair coagulation capacity and stimulate, rather than attenuate, pro-inflammatory platelet function.
-
Muscle weakness is highly prevalent during acute critical illness, with the poor exercise performance that occurs after critical illness being recognized as a consequence of skeletal muscles weakness. Advanced techniques to measure peripheral muscle strength are available, but they have limited use in the clinical setting. ⋯ At present, the mechanisms that underlie skeletal muscle wasting and weakness are poorly understood, but use of rehabilitation early in critical illness appears to have beneficial effects on outcome. The future direction will be to determine the underlying mechanisms as well as developing rehabilitation programmes during both the acute and the post critical illness stages.
-
Sepsis, a systemic inflammatory response to infective etiologies, has a high mortality rate that is linked both to excess cytokine activity and apoptosis of critical immune cells. Dexmedetomidine has recently been shown to improve outcome in a septic cohort of patients when compared to patients randomized to a benzodiazepine-based sedative regimen. We sought to compare the effects of dexmedetomidine and midazolam, at equi-sedative doses, on inflammation and apoptosis in an animal model of severe sepsis. ⋯ Sedation with midazolam and dexmedetomidine both improve outcome in polymicrobial severely septic rats. Possible benefits conveyed by one sedative regimen over another may become evident over a more prolonged time-course as both IL-6 and apoptosis were reduced by dexmedetomidine but not midazolam. Further studies are required to evaluate this hypothesis.