Acute lung injury in septic shock.

Over the past 20 years, substantial information has been gained concerning sepsis-associated ALI. Although the mortality from ARDS remains unchanged, the spectrum of disease has altered. Patients rarely die acutely from the direct sequelae of ALI, including hypoxemia, but most commonly demonstrate a protracted clinical course that eventuates in MSOF. Further, with improved resuscitation of medical and surgical emergencies, the profile of patients who develop ARDS has changed and now reflects an older and more complex patient. While the pathophysiology and mediators of tissue injury in septic ARDS is now better understood, effective therapeutic interventions have not yet resulted from early multicenter trials. It is clear from the recent multicenter trials on the effects of methylprednisolone dose that apparently useful therapies in animal models must undergo this form of investigation before widespread clinical dissemination. Without an effective and singular "golden bullet" for the treatment of the varied presentation of ARDS, it remains our contention that basic management principles of ARDS must continue to emphasize an aggressive approach to the identification and treatment of the septic focus while all efforts are concurrently exploited to reduce the potentially aggravating effects of secondary injury on microvascular function. Currently research into the diagnosis, prevention, and treatment of nosocomial pneumonia is an example of how secondary injury may be minimized in ALI. Further, it is important to recognize the potentially detrimental effects of various therapies on the microvascular membrane in ARDS.