ISSN:1070-5295    

出版商:OVID    

年代:2001

数据来源: OVID

ISSN:1070-5295    

出版商:OVID    

年代:2001

数据来源: OVID

摘要:

The sympathetic-parasympathetic balance may be altered in critically ill patients. Assessment of autonomic function provides information concerning prognosis, pathogenesis, and treatment strategies in ICU-relevant disorders. Proven tools are heart rate variability, baroreflex sensitivity, and, with limitations, cardiac chemoreflex sensitivity. New nonlinear methods are being evaluated that may predict risk more precisely in critically ill patients. This article summarizes application of these tools in the ICU. In addition, a model is introduced for investigating the impaired autonomic function in multiple organ dysfunction syndrome and sepsis, integrating extrinsic mechanisms and factors that are intrinsic to the cardiac tissue. By this combined approach, the authors hope to gain insight into the pathogenesis of multiple organ dysfunction syndrome. New pathophysiologic concepts are needed for the development of treatment strategies for this life-threatening disease.

ISSN:1070-5295    

出版商:OVID    

年代:2001

数据来源: OVID

摘要:

Nitric oxide regulates many aspects of myocardial function, not only in the normal heart but also in ischemic and nonischemic heart failure, septic cardiomyopathy, cardiac allograft rejection, and myocarditis. Accumulating evidence implicates the endogenous production of nitric oxide in the regulation of myocardial contractility, distensibility, heart rate, coronary vasodilation, myocardial oxygen consumption, mitochondrial respiration, and apoptosis. The effects of nitric oxide promote left ventricular mechanical efficiency,ie, appropriate matching between cardiac work and myocardial oxygen consumption. Most of these beneficial effects are attributed to the low physiologic concentrations generated by the constitutive endothelial or neuronal nitric oxide synthase. By contrast, inducible nitric oxide synthase generates larger concentrations of nitric oxide over longer periods of time, leading to mostly detrimental effects. In addition, the recently identified &bgr;3-adrenoceptor mediates a negative inotropic effect through coupling to endothelial nitric oxide synthase and is overexpressed in heart failure. An imbalance between &bgr;1and &bgr;2-adrenoceptor and &bgr;3-adrenoceptor, with a prevailing influence of &bgr;3-adrenoceptor, may play a causal role in the pathogenesis of cardiac diseases such as terminal heart failure. Likewise, changes in the expression of endothelial nitric oxide synthase or inducible nitric oxide synthase within the myocardium may alter the delicate balance between the effects of nitric oxide produced by either of these isoforms. New treatments such as selective inducible nitric oxide synthase blockade, endothelial nitric oxide synthase promoting therapies, and selective &bgr;3-adrenoceptor modulators may offer promising new therapeutic approaches to optimize the care of critically ill patients according to their stage and specific underlying disease process.

ISSN:1070-5295    

出版商:OVID    

年代:2001

数据来源: OVID

摘要:

Some evidence suggests that light to moderate alcohol consumption protects against cardiovascular diseases. However, this cardioprotective effect of alcohol consumption in adults is absent at the population level. Approximately 20 to 30% of patients admitted to a hospital are alcohol abusers. In medical practice, it is essential that patients' levels of consumption are known because of the many adverse effects that might result in the course of routine care. Ethanol damage to the heart is evident if alcohol consumption exceeds 90 to 100 g/d. Heavy ethanol consumption leads to increased risk for sudden cardiac death and cardiac arrhythmias. In patients with coronary heart disease, alcohol use was associated with increased mortality. An early response to drinking was an increased ventricular wall thickness to diameter ratio, possibly proceeding with continuous drinking to alcoholic cardiomyopathy, which had a worse outcome compared with idiopathic dilative cardiomyopathy if drinking was not stopped or at least reduced (< 60 g/d). In the ICU, patients with chronic alcoholism have more cardiac complications postoperatively. These complications probably are caused by biventricular dysfunction, particularly with the occurrence of severe infections or septic shock, events that are three to four times more frequent among chronic alcoholics than occasional drinkers or nondrinkers. To prevent further complications from drinking and for long-term management of drinking, patients with alcohol abuse and heart failure should be treated in brief intervention and follow-up programs. Prognosis is good even in patients with New York Heart Association class IV heart failure caused by cardiomyopathy if complete abstinence is accomplished. Noncompliance to smoking and alcohol restrictions, which are amenable to change, dramatically increases the risk for hospital readmissions among patients with heart failure.

ISSN:1070-5295    

出版商:OVID    

年代:2001

数据来源: OVID

ISSN:1070-5295    

出版商:OVID    

年代:2001

数据来源: OVID

摘要:

Derangements in coagulation and fibrinolysis are frequent complications of systemic infection, and septic shock is the most common recognized cause of disseminated intravascular coagulation. Anticoagulant therapy has been used as a treatment strategy for severe sepsis for several decades without compelling evidence of efficacy until the 2001 publication of the phase III trial with recombinant human activated protein C. Major phase III international trials with antithrombin and tissue factor pathway inhibitor also have been completed recently. The molecular mechanisms by which the clotting system interacts with the innate immune response have greatly facilitated the understanding of coagulation and the pathophysiology of septic shock. Anticoagulants such as recombinant human activated protein C and related agents may become the mainstay of adjuvant therapies for severe sepsis in the near future.

ISSN:1070-5295    

出版商:OVID    

年代:2001

数据来源: OVID

摘要:

Intravenous immunoglobulins (IVIg) are widely used as prophylaxis against and as supplemental treatment of sepsis and septic shock, although this concept does not belong to the currently approved medical indications for IVIg products. A reduction in mortality by pooled IVIgGMA more than by IVIgG alone was reported in the recent Cochrane database (eight trials, 492 patients). However, the failure to reduce mortality by IVIgG in the score-based immunoglobulin treatment in sepsis study (653 patients) seriously questions whether IVIgG may reduce mortality. Patients with streptococcal toxic shock syndrome might benefit from IVIg, although it remains questionable whether large controlled trials will ever be available. Intravenous immunoglobulin prophylaxis can undoubtedly reduce the occurrence of infections—especially pneumonias—in at-risk patients. More data are necessary to ascertain whether this beneficial effect is linked with a reduction of infection-related morbidity and mortality. Ongoing studies will document whether cardiac surgery patients with escalating systemic inflammatory response syndrome or mediastinitis will benefit from IVIg. IgM-specific complement inactivation may further stimulate the discussion of IVIgGMA superiority over IVIgG.

ISSN:1070-5295    

出版商:OVID    

年代:2001

数据来源: OVID

摘要:

Bone marrow transplantation and stem cell transplantation have become standard therapies offering potential cures for a number of hematologic malignancies and immunologic disorders. Severe infection remains a life threatening complication after transplantation, contributes significantly to morbidity, and may necessitate admission to the ICU. It is estimated that between 20 and 40% of patients receiving bone marrow transplant will require ICU admission in the initial posttransplantation phase. Historically, survival rates after admission to the ICU are dismal, particularly if mechanical ventilation is required for respiratory failure. Other organ involvement worsens the prognosis still further and has led to proposals for rationing or restricting access to critical care units and supportive measures. Recent studies have reported small but significant improvements in outcome after critical illness. Whether this improvement is a result of changes in levels of supportive care or a more defined patient selection is uncertain. Moreover, risk factors identifying patients who will benefit most from intensive support are poorly defined. However, it is generally accepted that respiratory failure requiring invasive mechanical ventilation is associated with a poor prognosis in this patient group. Early involvement of intensivists in the management of critical illness in transplant recipients is likely to continue to improve survival in this group of patients.

ISSN:1070-5295    

出版商:OVID    

年代:2001

数据来源: OVID

摘要:

The current clinical management of surgical patients with sepsis is governed by two principles: control of the source of infection and supportive management of the patient until recovery. Recently, there has been renewed interest in the concept of source control—in particular, its importance for evaluating and comparing clinical trials. This brief review highlights some of the developments in the surgical literature. Important recent publications center on source control, the management of systemic inflammatory response syndrome, necrotizing pancreatitis, acute diverticulitis, gastrointestinal fistulas, and the role of laparoscopy in surgical infections. Novel interventions in supportive care are being developed, and their clinical applicability and effectiveness will be improved with increased understanding of the pathophysiology of systemic inflammation.

ISSN:1070-5295    

出版商:OVID    

年代:2001

数据来源: OVID