[Infection as a cause of multiple organ failure. Definition, pathophysiology and diagnostic parameters].
BACKGROUND
Several clinical observations support the hypothesis that bacterial sepsis is the main aetiological factor in at least half of the patients developing multiple organ failure. Sepsis is defined as the pathophysiological alterations and life-threatening clinical consequences of the action of microorganisms or their products invading the blood stream from a focus of infection. The clinical course of sepsis is highlighted by initial multiorgan insufficiency progressing to severe multiple system organ failure.


METHODS
Pathogenetic bacteria and bacterial toxins arise from the septic focus, overcome the defence mechanisms of the body, continuously invade the blood stream, activate the biological cascade systems and initiate release of mediators from blood and tissue cells. Endotoxin and activated mediators cause endothelial and organ cell dysfunction and cell damage by at least three mechanisms: maldistribution of blood flow; cytotoxia; direct inhibition of oxygen-utilising cell enzymes.


METHODS
The septic disease begins with unspecific signs caused by invasion of bacteria, followed by alterations of the circulatory system, the blood clotting system, the metabolism, initiating vital organ dysfunctions and finally acute respiratory, renal, gastrointestinal, hepatic failure and septic encephalopathy.


METHODS
The clinical diagnosis of sepsis is based on the finding of an obvious septic focus with the presence of at least four of the following 5 criteria: (I) fever above 38.8 degrees C or hypothermia below 35.5 degrees C; (II) tachypnoea (greater than 24/min) or hypocapnia (PaCO2 less than 32 mmHg); (III) tachycardia (greater than 100 Bpm), (IV) leucocytosis (greater than or equal to 15.000/mm3) or leucopenia (greater than 5.000/mm3); (V) presence of at least one indicator for inadequate organ perfusion like mental alterations, hypoxaemia (PaCO2 less than 75 mmHg while breathing room air), hyperlactataemia (greater than 1,6 mmol/l), diuresis below 30 ml/h, drop in systolic blood pressure below 100 mmHg. A positive blood culture or a positive limulus test are frequent but are not considered to be obligatory for the diagnosis of sepsis.
Schuster
H P
HP
Medizinische Klinik I Städtisches Krankenhaus Hildesheim, Lehrkrankenhaus der Medizinischen Hochschule Hannover.
D001424:Bacterial Infections / Q000150:complications* / Q000503:physiopathology; D006801:Humans; D009102:Multiple Organ Failure / Q000209:etiology* / Q000503:physiopathology; D018805:Sepsis / Q000150:complications* / Q000503:physiopathology
Sepsis als Ursache des Multiorganversagens. Definition, Pathophysiologie und diagnostische Parameter.