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
-
The coronavirus disease (COVID-19) pandemic has threatened millions of lives worldwide with severe systemic inflammation, organ dysfunction, and thromboembolic disease. Within our institution, many critically ill COVID-19-positive patients suffered major thrombotic events, prompting our clinicians to evaluate hypercoagulability outside of traditional coagulation testing. We determined the prevalence of fibrinolysis shutdown via rotational thromboelastometry (ROTEM, Instrumentation Laboratories, Bedford, Mass) in patients admitted to the intensive care unit over a period of 3 weeks. ⋯ Eight of 9 (73%) of the VTE patients met criteria for fibrinolysis shutdown. Given the high rate of fibrinolysis shutdown in these patients, our data support using viscoelastic testing to evaluate for the presence of impaired fibrinolysis. This may help identify patient subsets who might benefit from the administration of fibrinolytics.
-
Comparative Study
ERK1/2 has Divergent Roles in LPS-Induced Microvascular Endothelial Cell Cytokine Production and Permeability.
Endothelial cells play a major role in inflammatory responses to infection and sterile injury. Endothelial cells express Toll-like receptor 4 (TLR4) and are activated by LPS to express inflammatory cytokines/chemokines, and to undergo functional changes, including increased permeability. The extracellular signal-regulated kinase 1/2 (ERK1/2) mediates pro-inflammatory signaling in monocytes and macrophages, but the role of ERK1/2 in LPS-induced activation of microvascular endothelial cells has not been defined. ⋯ The activation of ERK1/2 limits LPS-induced IL-6 production by HMVEC, while at the same time promoting HMVEC permeability. Conversely, ERK1/2 activation promotes IL-6 production by human monocytes. Our results suggest that ERK1/2 may play an important role in the nuanced regulation of endothelial cell inflammation and vascular permeability in sepsis and injury.
-
We hypothesize that a patient (pt) with accelerated thrombin generation, time to peak height (ttPeak), will have a greater odds of meeting critical administration threshold (CAT) criteria (> 3 packed red blood cell [pRBC] transfusions [Tx] per 60 min interval), within the first 24 h after injury, independent of international normalized ratio (INR). ⋯ Pts in hemorrhagic shock, who meet CAT+ criteria, are characterized by accelerated thrombin generation. In our multivariable analysis, both ttPeak and PT/INR have a complementary role in predicting those injured patients who will require a high rate of Tx.
-
Multicenter Study
Shock Index and Postpartum Hemorrhage in Vaginal Deliveries: A Multicenter Retrospective Study.
Shock index (SI), calculated by dividing heart rate by systolic blood pressure, is used to detect hemodynamic instability and hypovolemia. In obstetric practice, limited evidence is available regarding its usefulness in detecting postpartum hemorrhage (PPH). We aimed to evaluate the usefulness of SI in detecting PPH in vaginal deliveries using clinical data from 12 primary maternity care units in Japan. ⋯ SI is a better parameter for PPH detection in vaginal deliveries than other vital signs. However, clinical judgment must incorporate other vital signs and symptoms associated with hypovolemic shock due to the low sensitivity of SI.
-
Cell necroptosis, a form of regulated inflammatory cell death, is one of the mechanisms that controls cell release of inflammatory mediators from innate immune cells, such as polymorphonuclear neutrophils (PMNs), and critically regulates the progress of inflammation. Cell necroptosis features receptor-interacting protein (RIPK) 1 activation and necroptosome formation. This leads to loss of plasma membrane integrity, the release of cell contents into the extracellular space, and subsequent increased inflammation. ⋯ Using an in vivo mouse model of intratracheal injection (i.t.) of LPS and in vitro LPS stimulation of mouse PMN, we found that LPS-TLR4 signaling in PMNs activates and phosphorylates TBK1 and IKKε, which in turn suppress LPS-induced formation of the RIPK1-RIPK3-MLKL (necrosome) complex. TBK1 dysfunction by knockdown or inhibitor significantly increases the phosphorylation of RIPK1 (∼67%), RIPK3 (∼68%), and MLKL (∼50%) and promotes RIPK1-RIPK3 and RIPK3-MLKL interactions and increases PMN necroptosis (∼83%) in response to LPS, with subsequent augmented lung inflammation. These findings suggest that the LPS-TLR4-TBK1 axis serves as a negative regulator for PMN necroptosis and might be a therapeutic target for modulating PMN death and inflammation.