ABSTRACT
Septic shock is the most fulminant expression of systemic sepsis in patients with pneumonia. Driven by an overwhelming proinflammatory response,1 there is complete cardiovascular collapse owing to a combination of loss of peripheral vascular resistance owing to low vascular tone and depressed myocardial function.2 Multiorgan failure is an extremely common sequelae and the reported mortality rates range from 30 to 50 percent.3-7
Getting an accurate estimation of the frequency of shock in patients with pneumonia is difficult, particularly in community-acquired pneumonia where the true denominator is unknown given the large number of patients treated as out-patients or possibly never treated at all. Cohort studies of patients with community-acquired pneumonia generally report an incidence of septic shock between 5 and 20 percent,8-12 although this is heavily influenced by the type of hospital and availability of intensive care unit facilities. In the setting of nosocomial pneumonia, shock is encountered less often,13-18 although, when it does, the mortality rate may be even higher than with community-acquired sepsis.15 Again, establishing the appropriate baseline for comparison is difficult owing to the large number of mild nosocomial pneumonia’s that are either not recognized, treated empirically, or treated outside of intensive care units where the vast majority of case series that have been reported were collected.
