The concept of empirical antimicrobial agents in treatment of serious infection of critical ill patients

Abstract

Sepsis is defined as life-threatening organ dysfunction caused by a dysregulated host response to infection. This new definition emphasizes the primacy of the nonhomeostatic host response to infection, the potential lethality that is considerably in excess of a straightforward infection, and the need for urgent recognition. Septic shock is defined as a subset of sepsis in which underlying circulatory and cellular metabolism abnormalities are profound enough to substantially increase mortality. The 2001 task force definitions described septic shock as “a state of acute circulatory failure.” The task force favored a broader view to differentiate septic shock from cardiovascular dysfunction alone and to recognize the importance of cellular abnormalities. History taking and physical examination should be used to identify possible foci of source control. A critical action at this point is the measurement, documentation, and evaluation of vital signs, including temperature, blood pressure (BP), heart rate (HR), respiratory rate (RR) and oxygen saturation (if below 90% then supplemental oxygen should be immediately applied). Repeated recording of these parameters will be used to gauge clinical improvement or deterioration and trigger specific interventions. Consistently analysing the vital signs for the presence of SIRS criteria in any possible patient with sepsis will aid in the early recognition of critical illness. Initial laboratory and radiographic testing is aimed at locating a source of infection and identifying evidence of organ dysfunction. Common laboratory studies include a complete blood count (white blood cell count including a differential of subtypes and measure of bands, haemoglobin and haematocrit, platelets), chemistries (electrolytes, bicarbonate, creatinine, glucose), prothrombin time (PT)/international normalized ratio (INR), liver transaminases, bilirubin, and either arterial or venous blood gas analysis with the inclusion of a serum lactate level. Urinalyses are of high-yield, particularly in patients older than 65. Prompt recognition of the septic patient is critical, and early localization along the sepsis spectrum of illness (sepsis, severe sepsis, septic shock) helps to define the early goals of management. The initial evaluation of patients with sepsis includes the rapid establishment of multiple points of intravenous (IV) access with anticipation for the need for fluid