SEVERE SEPSIS

Infection has become a common cause of morbidity and mortality in inte nsive care. The syndromes seen have recently been defined by the Ameri can College of Chest Physicians to clarify the nomenclature used and p otentially to unify research projects. Sepsis is predisposed to by a n umber of co-existing pathologies and these will influence prognosis, a s will any pre-morbid condition. In addition, the infecting agent invo lved will influence outcome. Sepsis may produce multi-organ dysfunctio n via alterations in the endothelium with widespread vasodilatation an d altered permeability. These changes are mediated via a large array o f mediators produced either directly by the infecting agent or indirec tly from their action on host cells. Clinical changes include widespre ad vasodilatation with myocardial dysfunction, adult respiratory distr ess syndrome, reduced gastrointestinal perfusion with bacterial transl ocation across the gut wall and impaired renal, liver and endocrine fu nction. The management of patients with sepsis syndrome includes contr ol of the triggering infection both with antibiotics and surgical drai nage of infected sites. General supportive therapy is aimed at ensurin g adequate oxygen delivery by providing intraventricular filling and a ugmentation of cardiac output with inotropes and vasoactive drugs. Mec hanical ventilation may be required for respiratory support, continuou s dialysis for renal failure and nutritional support. The measurement of intraluminal pH, use of pulmonary artery catheters and goal-directe d therapy are recent issues that have been discussed. Together with in novative treatments, including the use of specific antibodies to media tors, these provide new approaches to sepsis which are currently being evaluated. In this arena of new therapy the importance of preventing sepsis should be emphasized.