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
-
We investigated in rats the influence of the lymphatic system and of tumor necrosis factor (TNF) on the lung inflammation resulting from intestinal ischemia/reperfusion (I/R) performed by 45-min occlusion of the superior mesenteric artery followed by 2 h of reperfusion. A group of rats had the thoracic lymph duct ligated before I/R. In lungs, intestinal I/R evoked a significant neutrophil recruitment, and enhanced microvascular permeability, in addition to generation of TNF in serum. ⋯ Similarly, intestinal LDH activity and serum TNF levels were unaffected. Overall, our data show that the pulmonary and gut injuries induced by intestinal I/R are partially dependent on TNF, which is conceivably generated in the injured gut tissue due to intestinal I/R and carried by the lymphatic system. Thus, the mesenteric lymphatic drainage seems to play a role as a path modulator of the pulmonary and intestinal dysfunctions that follow a gut trauma.
-
We tested whether nitric oxide (NO) could synergize with hypoxia to induce damage to the aorta isolated from rat. We found that 4 h of mild hypoxia (5% O2) caused substantial necrosis of isolated rat aortae (measured as lactate dehydrogenase release) if inducible NO synthase (iNOS) had previously been induced by endotoxin plus interferon-gamma. Mild hypoxia caused no significant necrosis in the absence of this inflammatory activation, and inflammatory activation caused little damage at a higher oxygen levels (21% oxygen). ⋯ A specific inhibitor of mitochondrial respiration, myxothiazol, caused necrosis of aortae over a similar time course to NO. DETA/NO plus mild hypoxia-induced cell death was substantially reduced by a glycolytic intermediate 3-phosphoglycerate, suggesting that necrosis resulted from energy depletion secondary to respiratory inhibition. This NO-induced sensitization of aorta to mild hypoxia may be important in sepsis and other pathologies where iNOS is expressed.
-
After asphyxia, it is standard to resuscitate the newborn with 100% oxygen, which may create a hypoxia-reoxygenation process that may contribute to subsequent myocardial dysfunction. We examined the effects of graded reoxygenation on cardiac function, myocardial glutathione levels, and matrix metalloproteinase (MMP)-2 activity during recovery. Thirty-two piglets (1-3 days old, weighing 1.5-2.1 kg) were anesthetized and instrumented for continuous monitoring of cardiac index, and systemic and pulmonary arterial pressures. ⋯ The hypoxia-reoxygenated (21%-100%) hearts had similarly increased MMP-2 activity and decreased glutathione levels (P < 0.05, 100% vs. controls), which correlated significantly with cardiac index and stroke volume during reoxygenation, and similar features of early myocardial necrosis. In neonatal resuscitation, if used with caution because of a slower resolution of pulmonary hypertension, 21% reoxygenation results in similar cardiac function and early myocardial injury as 50% or 100%. The significance of higher oxidative stress with high oxygen concentration is unknown, at least in the acute recovery period.
-
Hypotensive resuscitation (Hypo) has been considered an alternate resuscitation strategy in clinical settings that prevent the application of standard Advanced Trauma Life Support care. However, validation of this approach when used for prolonged periods of time remains to be demonstrated. The purpose of this study was to evaluate prolonged Hypo as an alternative to standard resuscitation using various currently available resuscitative fluids. ⋯ HEX required significantly less intravenous fluid (0.7x total estimated blood volume [EBV]) compared with HypoLR (1.9x EBV) and StandLR (3.2x EBV) (P < 0.05). Although HBOC required the smallest fluid volume (0.4x EBV), survival was no better than C and it resulted in the most significant acidosis. These results support the decision to use Hextend for Hypo, a strategy currently being applied on the battlefield.
-
Randomized Controlled Trial Clinical Trial
Effects of high-dose of intravenous immunoglobulin and antibiotics on survival for severe sepsis undergoing surgery.
The objective of this study was to assess the impact on outcome of adjuvant therapy (high-dose of immunoglobulin [Ig] M-enriched intravenous Ig, IVIG) in intensive care unit (ICU) patients who underwent surgery by abdominal sepsis. This was a prospective, randomized, double-blind, controlled study set in the medical/surgical ICUs of seven teaching hospitals. Patients with severe sepsis and septic shock of intra-abdominal origin admitted to the ICU within 24 h after the onset of symptoms were included in the study. ⋯ IAT was the only variable independently associated with death (odds ratio, 19.4) in a logistic regression model. We conclude that IVIG administration, when used in combination with adequate antibiotics, improved the survival of surgical ICU patients with intra-abdominal sepsis. The initial choice of antibiotic has a dramatic impact on outcome.