Hello and welcome to the zero to finals podcast. My name is Tom and in this episode I'm going to be talking to you about sepsis.

If you want to follow along with written notes on this topic, you can follow along at serodafinals.com

in the infectious diseases section or in the infectious diseases section of the zero finals medicine book.

Let's get straight into it.

Sepsis is a condition where the body launches a large immune response to an infection that

causes systemic inflammation and organ dysfunction.

Let's start this episode off by understanding the pathophysiology of sepsis.

The pathogens are recognised by macrophages, lymphocytes and mass cells in the immune system.

These cells then respond by releasing vast amounts of cytokines,

like interleukins and tumour necrosis factor, and these cytokines

alert the immune system to an invader. These cytokines activate other parts of the immune system,

and this other immune system activation leads to further release of chemicals, such as nitrous oxide,

that causes vasodilation. And it's the immune response that causes inflammation throughout the body.

Many of these cytokines cause the endothelial lining of blood vessels

or the inner lining of the blood vessels to become more permeable.

And this allows fluid to shift across the lining of the blood vessel,

leaking out of the blood vessel into the extracellular space.

This leads to edema, and it also reduces the intravascular volume.

So it reduces the amount of fluid that's in the blood vessels,

and that fluid shifts to the tissues causing edema.

Now this edema around the blood vessels creates a space between the blood and the tissues.

So this reduces the amount of oxygen that can travel from the blood into the tissues

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