1. Surgical Biology Flashcards
Define SIRS, SEPSIS and MODS and give a brief example of each.
Describe the process of MODS.
SIRS = systemic inflammatory response syndrome; clinical syndrome of inflammation that may occur with or without infection (i.e. septic vs non-septic SIRS). Pathogenesis is complex and incompletely understood. Based on 4 criteria, being temperature, heart rate, respiratory rate and white blood cell count or percentage of band neutrophils.
SEPSIS = life-threatening organ dysfunction caused by a dysregulated host response to infection. New definition emphasises the primacy of non-homeostatic host response to infection, potential lethality in excess of straightforward infection, with the need for urgent recognition, effectively moving the new definition into the slot previously held by ‘severe sepsis’.
MODS = multiple organ dysfunction; multifactorial clinical syndrome the result of many insults and injuries that have occurred throughout the body secondary to sepsis. Can lead to AKI, ARDS, DIC, CARS and/or CIRCI.
PROCESS OF MODS:
1. BEGINS WITH * Overwhelming proinflammatory cytokines **
Also lead to:
2. Endothelial activation causing clotting cascade activation and microthrombosis, causing ischaemia and tissue hypoxia. Progression to DIC.
3. Direction injury by ROS and complement resulting in further loss of functional tissue
4. Direct tissue damage from initial injury
5. Oedema formation by modification of Starling forces (albumin leaves and endothelial gaps increase), resulting in increased distance for oxygen transfusion
6. Apoptosis, programmed cell death, triggered by multiple pathways including proinflammatory cytokines
7. Impaired oxygen delivery to tissues from hypoperfusion, anaemia and/or hypoxaemia
