The dynamic stages of sepsis
- A local infection overcomes the body’s local defense mechanisms, and pathogenic microorganisms and the toxins they produce invade the circulatory system from the original site of infection, triggering a general inflammatory response. The blood vessels around the infection focus expand and become more permeable. The release of messenger substances (mediators of inflammation) allows white blood cells to penetrate the vascular walls into the tissues to fight the pathogens. The blood in the micro-vessels surrounding the infection coagulates as a defence mechanism.
- This inflammatory response leads to collateral damage: circulating mediators affect the function of individual organs, which start to deteriorate and then completely fail.
- Several organs stop functioning, either sequentially or simultaneously. In severe cases, blood pressure drops dramatically, the heart races, the oxygen supply to the blood via the lungs deteriorates, the oxygen supply to the organs and tissues is choked, the kidneys stop producing urine, and the patient’s mental status is gravely impaired. The patient’s life is in acute danger. Doctors call this septic shock.