Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0036690 (sepsis)
 59,461 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Treatment of hemodynamic instability in septic shock often demands the administration of vasopressor agents, although these may have deleterious effects on microcirculatory homeostasis. Inhibition of nitric oxide synthase (NOS) has been suggested as an alternative therapeutic approach, as NO formation may be excessively increased in sepsis. To compare the effects of epinephrine titration, non-selective NOS inhibition by L-NMMA and selective inhibition of inducible NOS (iNOS) by 1400W on hemodynamics and on the regulation of microcirculation in a rat model of endotoxic shock, we intravenously injected endotoxin (LPS) or saline to male Wistar rats and after 2 hours randomized LPS treated rats into four different groups that received either saline, norepinephrine, L-NMMA or 1400W (n = 6 per group). Three hours after LPS administration, rats presented with severe systemic arterial hypotension (64 +/- 3 vs. 115 +/- 4 mmHg, p < 0.001), unresponsiveness to volume treatment, lactate acidosis and a marked increase in plasmatic nitrite and nitrate levels (15 +/- 8 vs. 263 +/- 47 microM, p < 0.001). Measurement of the tissue oxygenation in the ileum mucosal layer by the Erlangen micro-lightguide spectrophotometer (EMPHO) technique demonstrated marked heterogeneity of hemoglobin saturation, with appearance of low oxygenated areas. Norepinephrine, usually stabilizing blood pressure (99 +/- 7 vs. 67 +/- 4 mmHg 60 min after infusion, p < 0.01), increased lactate formation (7.9 +/- 0.2 vs. 3.7 +/- 0.5 mM, p < 0.001) and drastically increased low oxygenated regions in the ileum mucosal layer. L-NMMA similarly increased blood pressure (92 +/- 6 vs. 67 +/- 4 mmHg 60 min after infusion, p < 0.05), but did not enhance lactate acidosis. However, some further deterioration of mucosa oxygenation was again noted. 1400W forwarded stabilization of blood pressure (88 +/- 5 vs. 67 +/- 4 mmHg 60 min after injection, p < 0.05), reduced plasmatic nitrite and nitrate levels similar to L-NMMA, without an aggravation of lactate acidosis. In addition, mucosal oxygenation did not deteriorate in response to this agent. Thereby, we conclude that in a rat model of endotoxic shock selective iNOS inhibitors are superior to non-specific NOS inhibitors and in particular to norepinephrine for the treatment of macro- and microcirculatory abnormalities in experimental septic shock.
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PMID:Effect of nitric oxide synthase (NOS) inhibition on macro- and microcirculation in a model of rat endotoxic shock. 1660 26

The objective of the present study was to assess the incidence, risk factors and outcome of patients who develop acute renal failure (ARF) in intensive care units. In this prospective observational study, 221 patients with a 48-h minimum stay, 18-year-old minimum age and absence of overt acute or chronic renal failure were included. Exclusion criteria were organ donors and renal transplantation patients. ARF was defined as a creatinine level above 1.5 mg/dL. Statistics were performed using Pearsons' chi2 test, Student t-test, and Wilcoxon test. Multivariate analysis was run using all variables with P < 0.1 in the univariate analysis. ARF developed in 19.0% of the patients, with 76.19% resulting in death. Main risk factors (univariate analysis) were: higher intra-operative hydration and bleeding, higher death risk by APACHE II score, logist organ dysfunction system on the first day, mechanical ventilation, shock due to systemic inflammatory response syndrome (SIRS)/sepsis, noradrenaline use, and plasma creatinine and urea levels on admission. Heart rate on admission (OR = 1.023 (1.002-1.044)), male gender (OR = 4.275 (1.340-13642)), shock due to SIRS/sepsis (OR = 8.590 (2.710-27.229)), higher intra-operative hydration (OR = 1.002 (1.000-1004)), and plasma urea on admission (OR = 1.012 (0.980-1044)) remained significant (multivariate analysis). The mortality risk factors (univariate analysis) were shock due to SIRS/sepsis, mechanical ventilation, blood stream infection, potassium and bicarbonate levels. Only potassium levels remained significant (P = 0.037). In conclusion, ARF has a high incidence, morbidity and mortality when it occurs in intensive care unit. There is a very close association with hemodynamic status and multiple organ dysfunction.
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PMID:Incidence, risk factors and prognostic factors of acute renal failure in patients admitted to an intensive care unit. 1690 22

Current therapy of septic/vasodilatory cardiovascular failure includes volume resuscitation and infusion of inotropic and vasopressor agents. Norepinephrine is the first-line vasoconstrictor, and can stabilize hemodynamic variables in most patients. Nonetheless, irreversible cardiovascular failure which is resistant to conventional hemodynamic therapies still is the main cause of death in patients with severe sepsis and septic shock. In such advanced, catecholamine-resistant shock states, arginine-vasopressin (AVP) has repeatedly caused an increase in mean arterial blood pressure, a decrease in toxic norepinephrine-dosages, as well as further beneficial hemodynamic, endocrinologic and renal effects. Although AVP exerted negative inotropic effects in previous clinical trials and in selected animal experiments, a continuous low-dose AVP infusion during advanced septic/vasodilatory shock caused a decrease in cardiac index only in patients with a hyperdynamic circulation. Adverse effects on gastrointestinal circulation and the systemic microcirculation can not be excluded, but have not yet been confirmed in clinical prospective trials. Negative side effects of a supplementary AVP therapy are an increase in total bilirubin concentrations, and a decrease in platelet count. A transient increase in hepatic transaminases during AVP infusion is most likely related to preceding hypotensive episodes. Important points which must be considered when using AVP as a "rescue vasopressor" in septic/vasodilatory shock states are: 1) AVP infusion only in advanced shock states that can not be adequately reversed by conventional hemodynamic therapy (e.g. norepinephrine >0,5-0,6 mug/kg/min), 2) presence of normovolemia, 3) AVP infusion only in combination with norepinephrine, 4) strict avoidance of bolus injections and dosages >4 IU/h. Effects of a supplementary AVP infusion in advanced vasodilatory shock on survival are currently examined in a large, prospective multicenter trial in North America and Australia.
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PMID:[Arginine-vasopressin in septic and vasodilatorial shock]. 1715 83

In patients with cirrhosis, acute renal failure is due to prerenal failure (a result of decreased renal perfusion) and tubular necrosis. There are 3 main causes of prerenal failure: 'true hypovolemia' (which complicates hemorrhage, gastrointestinal or renal fluid losses), sepsis, and type 1 hepatorenal syndrome (HRS). Prerenal failure may also be due to the administration of non-steroidal antiinflammatory drugs, or intravascular radiocontrast agents. Prerenal failure is reversible after restoration of renal blood flow. Treatments target the cause of hypoperfusion, and fluid replacement is used to treat 'non-HRS' prerenal failure. In patients with type 1 HRS with very low short-term survival rate, liver transplantation is the ideal treatment. Systemic vasoconstrictor therapy with terlipressin (combined with intravenous human albumin), noradrenaline (combined with albumin and furosemide) or midodrine (combined with octreotide and albumin) may improve renal function in patients with type 1 HRS waiting for liver transplantation. MARS (for Molecular Adsorbent Recirculating System) and the transjugular intrahepatic portosystemic shunt may also improve renal function in these patients. In patients with cirrhosis, acute tubular necrosis is mainly due to an ischemic insult to the renal tubules. Studies are needed on the natural course and treatment (e.g., renal-replacement therapy) of acute tubular necrosis in patients with cirrhosis.
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PMID:Diagnosis and treatment of acute renal failure in patients with cirrhosis. 1722

The use of catecholamines to defend and resuscitate patients with septic shock remains a cornerstone of intensive care medicine. The pharmacological support of the failing circulation during sepsis and septic shock should be directed at augmenting perfusion of vital organs and facilitating venous return, rather than peripheral arterial vasoconstriction. There appears to be a teleological rationale for primary use of catecholamines to augment failing endogenous neurohumoral and neuroendocrine cardiovascular systems. To this end, it seems intuitive to use the predominant naturally occurring catecholamine, noradrenaline, as the first-line agent for circulatory failure, although there are no definitive clinical trials to support this. Adrenaline has an established place in many parts of the world, particularly low-income countries, and appears to be equivalent to noradrenaline for reversing septic shock. There is increasing evidence for adverse neuroendocrine and immunological effects of dopamine, warranting circumspection about its use. The use of synthetic inotropes and vasopressors for septic shock remains limited, with little biological rationale. Clinicians should wait for definitive outcome-based trials of these expensive agents before incorporating them into practice. Supplemental endocrine replacement therapy with low-dose corticosteroids and vasopressin appears biologically plausible and has an emerging role. Results of large-scale, high-quality trials of endogenous catecholamines for sepsis and septic shock are awaited. These may provide additional, important information for evidence-based guidelines, which currently remain of limited clinical utility.
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PMID:An appraisal of selection and use of catecholamines in septic shock - old becomes new again. 1722 75

Volatile anesthetics such as isoflurane have been shown to offer anti-inflammatory effects during experimental endotoxemia whereas the alpha-adrenergic vasopressor norepinephrine exhibits proinflammatory properties on systemic cytokine release under the same conditions. However, during major surgery and in patients with systemic inflammatory response syndrome or sepsis both agents are frequently administered concurrently. We therefore aimed to investigate the influence of preexisting i.v. administration of noradrenaline or vasopressin on the anti-inflammatory effects of isoflurane during experimental endotoxemia. Anesthetized, ventilated Sprague-Dawley rats (n=7 per group) were randomly treated. In the LPS-only group, animals received lipopolysaccharide (LPS, 5 mg/kg, i.v.) with no further specific treatment. In the LPS-isoflurane group, isoflurane inhalation at 1 MAC was initiated simultaneously with induction of endotoxemia (LPS 5 mg/kg, i.v.). Animals in the LPS-isoflurane-norepinephrine group received norepinephrine infusion at 50 microg/kg/h 10 min prior to injection of LPS and inhalation of isoflurane. In the LPS-isoflurane-vasopressin group, vasopressin was administered at 0.5 IE/kg/h 10 min prior to LPS and isoflurane. In the LPS-norepinephrine and the LPS-vasopressin groups the infusion of each vasopressor was started prior to LPS injection without any application of isoflurane. A Sham group served as the control. After 4 h of endotoxemia, plasma levels of TNFalpha, IL-1beta and IL-10 were measured. Alveolar macrophages (AM) were cultured ex vivo for nitrite assay. Induction of endotoxemia resulted in a significant rise in measured plasma cytokines and nitrite production from cultured AM. Inhalation of isoflurane significantly attenuated plasma levels of TNFalpha (-65%) and IL-1beta (-53%) compared to the LPS-only group whereas it had no effect on nitrite production from cultured AM. Preexisting infusions of norepinephrine or vasopressin abolished the anti-inflammatory effects of isoflurane. The data demonstrate that the administration of norepinephrine or vasopressin both counteracted the anti-inflammatory effects of inhaled isoflurane on proinflammatory cytokine release during experimental endotoxemia in rats.
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PMID:Norepinephrine and vasopressin counteract anti-inflammatory effects of isoflurane in endotoxemic rats. 1778 93

Cardiovascular dysfunction in septic shock (SS) is ascribed to the release of inflammatory mediators. Norepinephrine (NE) is often administered to treat low MAP in SS. We recently found that lysozyme c (Lzm-S) released from leukocytes was a mediator of myocardial depression in an Escherichia coil model of SS in dogs. This effect can be blocked in an in vitro preparation by chitobiose, a competitive inhibitor of Lzm-S. In the present study, we examined whether chitobiose treatment can reverse myocardial depression and obviate NE requirements in two respective canine E. coli preparations. In a 6-h study, we administered chitobiose after 3.5 h of E. coli bacteremia and compared stroke work (SW) and MAP at 6 h with a sepsis control group. In a 12-h study, we determined whether chitobiose treatment can reduce the need for NE requirements during 12 h of bacteremia. In the latter study, either chitobiose or NE was given when MAP decreased approximately 20% from the presepsis value in respective groups. In anesthetized, mechanically ventilated dogs, we monitored hemodynamic parameters during continuous E. coli infusion. In the 6-h study, chitobiose improved SW and MAP at the 6-h period as compared with the nontreated sepsis group. In the 12-h study, SW and MAP increased after chitobiose without the necessity of NE administration. These results suggest that inhibitors of Lzm-S such as chitobiose may improve myocardial depression and reduce the need for NE requirements in SS.
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PMID:N,N'-diacetylchitobiose, an inhibitor of lysozyme, reverses myocardial depression and lessens norepinephrine requirements in Escherichia coli sepsis in dogs. 1788 42

Severe sepsis and septic shock have an increasing incidence and unchanged high mortality. Early diagnosis is necessary to slow the progression of organ dysfunction and improve outcome. Early administration of broad-spectrum antimicrobial therapy, early and aggressive hemodynamic therapy, and surgical source control are the most promising therapeutic approaches. Norepinephrine is the first choice as a vasopressor. Starches for volume resuscitation, intensive insulin therapy (aiming at 80-110 mg/dl), and low-dose hydrocortisone are not recommended outside randomized trials. Recombinant activated protein C is one choice for certain patients. The German Sepsis Competence Network (SepNet) is currently investigating other open questions.
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PMID:[Sepsis therapy: present guidelines and their application]. 1832 Jan 53

Catecholamines are frequently used in sepsis, but their interaction with mitochondrial function is controversial. We incubated isolated native and endotoxin-exposed swine liver mitochondria with either dopamine, dobutamine, noradrenaline or placebo for 1 h. Mitochondrial State 3 and 4 respiration and their ratio (RCR) were determined for respiratory chain complexes I, II and IV. All catecholamines impaired glutamate-dependent RCR (p = 0.046), predominantly in native mitochondria. Endotoxin incubation alone induced a decrease in glutamate-dependent RCR compared to control samples (p = 0.002). We conclude that catecholamines and endotoxin impair the efficiency of mitochondrial complex I respiration in vitro.
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PMID:Effects of endotoxin and catecholamines on hepatic mitochondrial respiration. 1960 62

Calcium plays an important role in determining vascular smooth muscle tone. Norepinephrine (NE)-induced vascular contraction contains two components: 1) Ca2+ release from the sarcoplasmic reticulum as the fast phase and 2) Ca2+ influx via a voltage-dependent calcium channel as the slow phase. This study used functional isometric tension recording to evaluate mediators contributing to abnormal NE-induced Ca2+ handling and reactivity in isolated thoracic aortas from septic rats. Sepsis was induced by cecal ligation and puncture (CLP), and thoracic aortas were removed at 18 h after CLP. Our results showed that rats that received CLP for 18 h manifested severe hypotension and vascular hyporeactivity to NE in vivo. This vascular hyporeactivity to NE was also observed in the aorta obtained from CLP-induced sepsis rat. Both the fast and slow phases of NE-induced contraction were reduced in aortas from sepsis rats. To clarify what possible mediators contribute to the abnormal Ca2+ handling in aortas from sepsis animals, inhibitors of Ca2+ channel and release were used. Inhibition by 2-aminoethoxy-diphenyl borane, ryanodine, and cyclopiazonic acid of the NE-induced contraction in Ca2+-free solution was greater in the aorta from sepsis rats and inhibitions of cyclopiazonic acid and ryanodine, but not of 2-aminoethoxy-diphenyl borane, were attenuated by NOS inhibitor N[omega]-nitro-l-arginine methyl ester. In addition, the attenuation of NE-induced contraction by nifedipine in the aorta was also greater in the CLP group. Our results suggest that abnormal NE-induced Ca2+ handling associated with vascular hyporeactivity in the CLP-induced sepsis is caused by a major decrease in sarcoplasmic reticulum function and a minor impairment of voltage-dependent Ca2+ channels on membrane to Ca2+ handling, at least, in the aorta, and this could be attributed to an overproduction of NO in sepsis.
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PMID:NO contributes to abnormal vascular calcium regulation and reactivity induced by peritonitis-associated septic shock in rats. 1974 6


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