ABSTRACT
Focus on visible macrophysiology (systems and organs) has increasingly been replaced by recognition that disease processes originate primarily at microphysiological levels; organ/system failure follows widespread cell failure. Cell function relies on chemical reactions, which require both oxygen and energy. Absence of oxygen and energy sources (mainly blood glucose) therefore quickly leads to cell damage and failure. Inflammation is cell-tissue’s homeostatic response to protect itself, but exaggerated and inappropriate inflammatory responses cause life-threatening disease such as systemic inflammatory response syndrome (SIRS – see Chapter 33). Restoring oxygen and energy supplies to failing cells may enable cell survival, reversing critical illness.
