Shock : molecular, cellular, and systemic pathobiological aspects and therapeutic approaches : the official journal the Shock Society, the European Shock Society, the Brazilian Shock Society, the International Federation of Shock Societies
-
Assessment of regional blood flow changes is difficult in the clinical setting. We tested whether conventional pulmonary artery catheters (PACs) can be used to measure regional venous blood flows by inverse thermodilution (ITD). Inverse thermodilution was tested in vitro and in vivo using perivascular ultrasound Doppler (USD) flow probes as a reference. ⋯ No significant correlation was found for cerebral and femoral flows. Inverse thermodilution using conventional PAC compared moderately well with USD for renal but not for other flows despite good in vitro correlation in various conditions. In addition, this method has significant technical limitations.
-
Hemoglobin glutamer-200 (HbG) might be an alternative to human blood. However, artificial oxygen carriers are initially successful to restore oxygen supply but may induce organ dysfunction and increase mortality several days after application in terms of delayed side effects. Impairment of microcirculation and an inflammatory cytokine response through induction of endothelin (ET) 1 may contribute. ⋯ Application of bosentan after HbG but not after vehicle pretreatment significantly improved PDRICG and liver perfusion, whereas NAD(P)H and hepatocellular injury decreased. Furthermore, cytokine release changed to an anti-inflammatory response. These data suggest an HbG-dependent increase of ET-1, which may contribute to delayed side effects under shock conditions.
-
High-mobility group box 1 (HMGB1) is a late mediator of the systemic inflammation associated with sepsis. Recently, HMGB1 has been shown in animals to be a mediator of hemorrhage-induced organ dysfunction. However, the time course of plasma HMGB1 elevations after trauma in humans remains to be elucidated. ⋯ Plasma HMGB1 is significantly increased within 1 h of trauma in humans with marked elevations occurring from 2 to 6 h postinjury. These results suggest that, in contrast to sepsis, HMGB1 release is an early event after traumatic injury in humans. Thus, HMGB1 may be integral to the early inflammatory response to trauma and is a potential target for future therapeutics.
-
We sought to determine (a) if early lactate clearance is associated with improved survival in emergency department patients with severe sepsis and (b) the concordance between central venous oxygen saturation (ScvO2) optimization and lactate clearance during early sepsis resuscitation. Within a multicenter shock research network that uses quantitative resuscitation for severe sepsis, we analyzed prospectively collected registries of consecutive emergency department patients diagnosed with severe sepsis at three urban hospitals. Inclusion criteria are as follows: (a) age older than 17 years, (b) two or more systemic inflammation criteria, (c) systolic blood pressure 90 mmHg or less after fluid challenge or initial lactate of 4 mmol/L or greater, and (d ) initial and repeat lactate measurement within 6 h of resuscitation initiation. ⋯ We found discordance between ScvO2 optimization and lactate clearance; 79% of lactate non-clearance had concomitant ScvO2 of 70% or greater. In this multicenter cohort of sepsis patients, failing to clear lactate during resuscitation carried a high risk of death, and ScvO2 optimization did not reliably exclude lactate non-clearance. These data provide rationale for a clinical trial of lactate clearance as a distinct end point of early sepsis resuscitation.
-
Toll-like receptor 4 (TLR4) plays a major role in regulating the innate immune response, which is related to postoperative complications. Although inflammatory capacity and TNF-alpha synthesis were altered on monocytes after cardiopulmonary bypass (CPB), whether the CPB and the CPB-induced TNF-alpha affect TLR4 expression on monocytes have not yet clarified. We speculate that the changing of TNF-alpha level during CPB may be involved in monocytic TLR4 expression. ⋯ We also demonstrated in clinical samples with confocal microscopy and flow cytometry that CPB led to an elevation of TTP in monocytes. In conclusion, CPB and TNF-alpha decrease TLR4 expression on monocytes; TTP expression and mitogen-activated protein kinase-signaling pathways play critical roles in CPB- and TNF-alpha-mediated decreases of TLR4 on monocytes. Our results suggest that using TTP to control cytokine message decay rate may be a promising approach for controlling system inflammation and preventing post-CPB complications.