APACHE system developed in 1970s to address DRG limitations in ICU. System initially used single blood test with threshold-based classification. APACHE II was simplified to paper-based system for efficiency. System was unexpectedly well-received at critical care congress
ICU is a specialized hospital department providing intensive medical care. Florence Nightingale reduced Crimean War mortality from 60% to 2.2%. First global ICU established in Copenhagen by Bjørn Aage Ibsen in 1953. Dwight Harken opened first US ICU in 1951
Fat enters bloodstream causing symptoms within a day. Main symptoms include petechiae, decreased consciousness, and shortness of breath. Mortality rate is approximately 10-20%. Symptoms typically appear 12 hours to 3 days after diagnosis
Blood volume is the total blood in circulatory system. Typical adult has approximately 5 liters of blood. Blood volume is regulated by kidneys. Blood volume is 70 ml/kg in males, 65 ml/kg in females
ALF occurs when liver cells lose 80-90% function rapidly after initial jaundice. Disease severity classified as hyperacute (within 1 week), acute (8-28 days), or subacute (4-12 weeks)
PI is the ratio of pulsatile to non-pulsatile pulse wave in fingers. PI reflects blood volume changes with each heartbeat. Middle finger is most common PI monitoring site. PI values vary between healthy adults (0.3-10) and critically ill patients