Surgery
-
The use of beta blockers in surgical patients has been suggested to decrease perioperative cardiac events. However, the overall risk reduction, on the basis of solely aggregate data from randomized studies, is unknown. The objective is to evaluate the effect of perioperative beta blockade in noncardiac surgery for protection against mortality or cardiac events. ⋯ This report highlights for the first time the aggregated risk reduction from all published randomized controlled trials, and shows the protection of perioperative beta blockade against both short-term complications and mortality.
-
Comparative Study
Ketamine attenuates liver injury attributed to endotoxemia: role of cyclooxygenase-2.
Endotoxic shock can cause end-organ dysfunction and liver injury. Critically ill patients frequently require surgical intervention under general anesthesia for source control. However, the effects of anesthetics on organ function during sepsis and their influence on inflammatory mediators such as cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS) remain to be fully elucidated. Because ketamine anesthesia has anti-inflammatory effects in some tissues, we hypothesized that it would attenuate lipopolysaccharide (LPS)-induced liver injury. ⋯ These data indicate that anesthetics differ in their effects on liver injury caused by LPS. Ketamine has hepatoprotective effects, while isoflurane does not. Moreover, the protective effects of ketamine are mediated, at least in part, through a reduction in COX-2 and iNOS protein that could be regulated via changes in NF-kappaB-binding activity.
-
Conventional resuscitation (CR) from hemorrhagic shock (HS) does not restore intestinal blood flow. Indicators of anaerobic metabolism suggest that cellular energy production also is compromised. We hypothesize that the direct intravenous delivery of lipid-encapsulated high-energy phosphates to cells improves intestinal perfusion during HS and resuscitation (RES). ⋯ Our data confirms that CR causes progressive intestinal hypoperfusion. Cellular resuscitation with direct intravenous energy delivery improves intestinal perfusion after CR and results in improved survival and less tissue edema.
-
Crystalloid infusion has been the standard prehospital fluid resuscitation in the United States for the past 35 years, but the emergence of a safe and effective hemoglobin-based oxygen carrier (HBOC) may change that practice. The purpose of this in vivo study is to simulate an existing multicenter prehospital trial of HBOC versus crystalloid to determine the effects in a controlled 2-event construct of postinjury multiple organ failure. ⋯ The findings in this controlled in vivo study suggest prehospital HBOC resuscitation improves the recovery from postshock oxygen debt and reduces postinjury organ dysfunction.
-
Evidence is emerging that the endoplasmic reticulum (ER) participates in initiation of apoptosis induced by the unfolded protein response and by aberrant Ca(++) signaling during cellular stress such as ischemia/reperfusion injury (I/R injury). ER-induced apoptosis involves the activation of caspase-12 and C/EBP homologous protein (CHOP), and the shutdown of translation initiated by phosphorylation of eIF2alpha. Sodium 4-phenylbutyrate (PBA) is a low molecular weight fatty acid that acts as a chemical chaperone reducing the load of mutant or unfolded proteins retained in the ER during cellular stress and also exerting anti-inflammatory activity. It has been used successfully for treatment of urea cycle disorders and sickle cell disease. Thus, we hypothesized that PBA may reduce ER-induced apoptosis triggered by I/R injury to the liver. ⋯ Reduction in ER stress-induced hepatocellular injury was achieved by the administration of PBA. Targeting the ER-associated cell death pathway might offer a novel approach to reduce I/R injury to the liver.