Renal failure in acute liver failure.

Renal failure develops in approximately 55% of all patients referred to specialized centres with acute liver failure. The renal failure may be secondary to the liver failure itself (and is termed the hepatorenal syndrome) or the renal failure may be a secondary insult that directly affects both liver and kidney alike (for example paracetamol overdose). The pathogenesis of the hepatorenal syndrome involves the development of a hyperdynamic circulation, with a lowering of renal perfusion pressure, the activation of the sympathetic nervous system, which renders the kidneys more susceptible to modest decreases in perfusion pressure, and increased synthesis of a variety of vasoactive mediators. These mediators can cause renal vasoconstriction, but more importantly they can also decrease the glomerular capillary ultrafiltration coefficient (Kf), thus causing a decline of glomerular filtration rate over and above that caused by renal vasoconstriction alone. The treatment of the renal failure in acute liver failure involves the optimization of renal haemodynamics and haemofiltration. Renal failure will always recover when there is recovery of liver function, and in the absence of a spontaneous hepatic recovery, liver transplantation will reverse the hepatorenal syndrome.     

Global left atrial failure in heart failure

The left atrium plays an important role in the maintenance of cardiovascular and neurohumoral homeostasis in heart failure. However, with progressive left ventricular dysfunction, left atrial (LA) dilation and mechanical failure develop, which frequently culminate in atrial fibrillation. Moreover, LA mechanical failure is accompanied by LA endocrine failure [deficient atrial natriuretic peptide (ANP) processing‐synthesis/development of ANP resistance) and LA regulatory failure (dominance of sympathetic nervous system excitatory mechanisms, excessive vasopressin release) contributing to neurohumoral overactivity, vasoconstriction, and volume overload (global LA failure). The purpose of the present review is to describe the characteristics and emphasize the clinical significance of global LA failure in patients with heart failure.     

Fulminant hepatic failure secondary to congestive heart failure

Summary An elderly female with an acute episode of congestive heart failure, unaccompanied by any periods of hypotension, developed fulminant hepatic failure with an accompanying coagulopathy. Attempts to establish an etiology for her acute hepatic insufficiency, other than cardiac failure, proved negative. Fulminant hepatic failure as a consequence of congestive heart failure, without prolonged periods of hypotension preceding alteration in hepatic function, has not heretofore been described. Liver function is adversely effected in congestive heart failure. Hepatic ammonia clearance is impaired in cardiac failure and may be diminished to the point of resulting in hepatic encephalopathy. Coagulopathy is a frequent concomitant of fulminant hepatic failure. Establishing a clear etiology for a coagulopathy in the face of concomitant liver disease is difficult, thus making any therapeutic intervention fraught with peril.Dr. Kisloff is supported by a training grant in gastroenterology AM 0567-08 from the National Institutes of Health. The authors wish to express their gratitude to Dr. Harold J. Fallon for his suggestions.     

Respiratory failure

Acute lung injury (ALI) and acute respiratory distress syndrome (ARDS) are common causes of hypoxemic respiratory failure. Multiple etiologies lead to direct and indirect pulmonary injury that progresses through an acute exudative phase, fibroproliferative phase, and recovery phase. Inflammatory mechanisms are thought to play a predominant role in the pathophysiology of ALI/ARDS. Mechanical ventilation with a lower tidal volume and an inspiratory plateau pressure of < or = 30 cm H2O is one intervention that has demonstrated a reduction in mortality. A clinical trial to determine the role of restrictive versus liberal fluid management is underway. Inhaled nitric oxide has been used to improve oxygenation but has not resulted in any outcome benefit. Glucocorticoids may be beneficial in the fibroproliferative phase of lung injury by suppressing chronic inflammation. Rigorous clinical trials of new and established interventions are required to determine optimum therapy and reduce mortality in ALI/ARDS.     

Heart failure

This article discusses the most important developments in heart failure reported during the last year. It contains a review of new findings on chronic heart failure, acute heart failure, cardiac resynchronization therapy, heart transplantation, with particular emphasis on the situation in Spain, and surgery in heart failure. In addition, the article describes progress in the treatment of anemia, vasopressin receptor antagonists, non-invasive ventilation, inotropic therapy, and resynchronization therapy in patients with heart failure and atrial fibrillation, and examines the current role of echocardiography in detecting asynchrony and in selecting patients.     

Heart failure

Heart failure is predominantly a disorder of older adults, and to a large extent the epidemiology of heart failure reflects the convergence of age-related changes in the cardiovascular system and the rising prevalence of age-related cardiovascular diseases. The diagnosis of heart failure in the elderly is often difficult because of the presence of atypical symptomatology and comorbid conditions. Similarly, optimal treatment frequently poses a therapeutic challenge because of the high prevalence of confounding medical, behavioral, psychosocial, and economic factors. In addition, there is a paucity of data on the pharmacotherapy of heart failure in the very elderly (over age 80), and in the large proportion of older patients with heart failure and preserved left ventricular systolic function. Despite these difficulties, a number of therapeutic options, including ACE inhibitors, digoxin, and possibly beta blockers and angiotensin receptor antagonists, have been shown to favorably affect the clinical course of heart failure in elderly patients. In addition, several studies have documented the efficacy of multidisciplinary heart failure disease management programs for reducing hospital admission rates, improving quality of life, and decreasing cost of care. At present, the three greatest challenges in managing older heart failure patients are: (1) to more effectively implement proven treatments, such as ACE inhibitors, disease management systems, and antihypertensive therapy; (2) to develop effective therapies for the treatment of diastolic heart failure; and (3) to develop more effective means for heart failure prevention. It is hoped that future studies will address each of these critically important issues.     

Baroreflex failure

The baroreflex receives less attention nowadays because most students of hypertension are convinced that faulty volume regulation by the kidneys is responsible for long-term blood pressure increases. However, unusual patients with bilateral destruction of the normal blood pressure-sensing mechanisms can develop profound chronic hypertension. We present 2 patients with baroreflex failure. Both had volatile hypertension with systolic readings up to 300 mm Hg documented over years. Both had muscle sympathetic nerve activity that was increased even while resting. Treating these patients was a stochastic challenge. The therapy is frequently based on medicines that are no longer commonly prescribed.     

Intestinal failure

Abstract The recognition of intestinal failure (IF) as a distinct clinical entity over the past 20 years has primarily come about through the emergence of increasingly successful treatment based on use of intravenous nutrition delivered both in hospital and at home. Intestinal failure has many and varied causes, and may be complete or partial, acute and short lived, or chronic and permanent. If the latter, lifetime dependence on parenteral nutrition will usually be indicated and where possible patients are trained in the techniques of home parenteral nutrition (HPN). The success of HPN is itself primarily dependent on meticulous catheter care protocols. Sufficient numbers of such patients have now been entered into randomized controlled trials for there to be an evidence base for this aspect of IF treatment. The balanced delivery of nutrients, especially when an enteral component is included, can prevent many of the complications, such as liver and bone disease, recorded as being associated with prolonged total parenteral nutrition. However, nutritional balance is difficult to achieve in the presence of total gut resection, multiple intestinal fistulas or persisting sepsis. Surgical approaches involving bowel lengthening and reversed loops are indicated in selected patients. They have limited success and carry with them the risk of further loss of precious residual bowel. Greatest promise is held out by intestinal transplantation, but the problems associated with the powerful immunosuppression required reduce the value of this treatment. Specialized referral units for patients with severe and persistent IF can produce a high percentage of clinically effective and cost-effective outcomes.     

Heart failure

Although heart failure is common, disabling, and deadly, there are now many effective treatments, at least for patients with low left-ventricular ejection fraction. For all, angiotensin-converting-enzyme inhibitors and beta blockers are the essential disease-modifying treatments, improving symptoms, reducing hospital admissions, and increasing survival. Implantable cardioverter defibrillators also improve survival. For patients with persistent symptoms, angiotensin-receptor blockers and aldosterone antagonists have additional benefits. These treatments are now preferred to digoxin, although this drug can still be useful at an earlier stage in patients with atrial fibrillation. In some patients with persistently severe symptoms and a wide QRS on the electrocardiogram, cardiac resynchronisation therapy also reduces mortality and morbidity. The role of other markers of ventricular dys-synchrony is under investigation. There is growing evidence that left-ventricular assist devices are indicated in some patients with end-stage heart failure. Organised delivery of care also improves outcome. However, there is still no firmly evidence-based treatment for heart failure with preserved ejection fraction. Many new pharmacological, device, and surgical treatments for heart failure are currently under evaluation in clinical trials, and other approaches, including stem-cell treatment, are at an earlier stage of investigation.