Sepsis @ acute-illness.com

There has recently been an interesting article published in the Critical care journal.  The effect of treatment with vasopressin during sepsis has been investigated.

Vasopressin

First a bit of background.  One of the problems during sepsis is leakage of plasma from the blood vessels which leads to a low blood pressure.  Vasopressin is of interest for two reasons.  Firstly it is an anti-diuretic, a fancy way of saying it makes you urinate less, and so you loose less water.  Secondly it is a vasoconstrictor, it narrows the blood vessels, which means you need less fluid to maintain a pressure.  Think of it as pinching the end of a garden hose.

Use in practice 

From the above it would be reasonable to think it may well be useful in sepsis.  Unfortunately it is not without problems as this recent article demonstrates.  Narrowing the blood vessels reduces the amount of blood which can flow.  If the blood flow is reduced too far then the organs won’t get the nutrients and oxygen they need to function and they will be injured.

The article claims that blood flow to the pancreas and the kidneys, which are frequently damaged during sepsis, is reduced.  No treatment is perfect and it may be that vasopressin still has a use in the treatment of sepsis but it should be used with caution.

Don’t forget to take a look at the article.  It is another one with open access which is great.

A recent paper has been published in which mice with severe sepsis when treated with EGCG, the major antioxidant in green tea, had a significantly lower death rate than controls. Initially I had dismissed it as all hype but on closer examination there may be something to it.

Why should we be sceptical?

Before I get into why this result is potentially interesting I’ll explain why I was (and you should be) initially sceptical. There have been a wide variety of compounds found to be amazingly successful in treating sepsis in animal models when administered prior to the onset of sepsis. Despite this out of 20 clinical trials (involving 10,000 patients) only 5 treatments have been shown to work. Only 2 of the 5 involved medicinal agents. I’ll probably go into more detail on this in a future post but the take home message here is that positive results in animal studies rarely transfer wel to humans.

Reasons for interest

1. The dose of EGCG was sensible. A significant increase in survival was seen with 4 mg/kg bodyweight. A cup of green tea contains between 15 and 50 mg so working from my weight (90 kg) it would be equivalent to approx. 11 cups of green tea.
2. EGCG was administered after the onset of sepsis. A problem with previous studies has been that a compound is shown to be effective if administered before onset of sepsis but not afterwards. In the clinic administering a compound before sepsis isn’t possible so these compounds have been of no use.

This is a very preliminary study but it is undoubtedly potentially interesting.

Thanks to eatingfabulous.com for prompting me to take a second look at this.

The paper is freely available. Hooray!

Sepsis is a massive challenge in modern medicine.  Despite significant investment in researching the condition the mortality rate, the percentage of people who die, is still shockingly high.  During this short post I’m going to try and answer the question, “What is sepsis?”

Over-reaction

The prevailing theory is that sepsis represents an uncontrolled inflammatory reaction to some insult.  Usually this insult would be an infection.  An almost identical condition, termed SIRS, systemic inflammatory response syndrome, can occur without infection and typically follows some form of trauma.

A lack of an agreed upon a definition plagued clinical trials and patient treatment until a little over a decade ago a consensus conference defined sepsis as ‘infection with evidence of systemic inflammation’.  Systemic inflammation was considered to be present if two or more of the following conditions were met

- Increased or decreased temperature
- Increased or decreased leukocyte (white blood cell) count
- Tachycardia (rapid heart beat)
- Rapid breathing

This was the first time the term SIRS was needed.  By including infection in the definition of sepsis a new term was needed for ’sepsis’ without infection and SIRS was coined.

Severe sepsis and septic shock

The term sepsis was further broken up with severe sepsis and septic shock used.  Severe sepsis is sepsis with organ dysfunction, frequently the lungs or kidneys.  The more organs that fail the higher the mortality rate.

Septic shock is severe sepsis with hypotension, low blood pressure, that persists after the administration of intravenous fluid.  The blood vessels are dilatated (widened) and the capillaries are more permeable than they should be.  This causes there to be less resistance to blood flow and the pressure drops.  The best analogy would be the garden hose.  If you pinch the end the water shoots out a good distance because it is under pressure but if you don’t pinch the end you get just a trickle.

That trickle isn’t enough to supply oxygen and nutrients to the body fast enough and you get hypoperfusion, hypoxia and organ dysfunction.

These are issues from basic sepsis onwards getting worse with severe sepsis until in septic shock the body is unresponsive to fluid administration.

In future articles I’ll discuss the symptoms of sepsis in greater detail and talk about the appropriate treatments.

Before I really get started with posting I thought it would be worthwhile writing a short post to explain what I hope to achieve with the site.

I’m currently researching sepsis as part of my degree and I was disappointed by the poor state of information on the web dealing with this topic.  There are thousands of academic articles dealing with this subject but unless you are part of an academic institution with a subscription research could cost a not so small fortune.  At $30 an article the price could quickly skyrocket.  In the past 3 months alone I would have burnt through $6000 in fees at this rate.

My aim with this site is to offer a wealth of information covering not only the background to sepsis but also the latest research.

I  have a decent list of ideas for background articles and I’m sure there will be plenty in the news I’ll want to cover but if you have any specific questions you want answering please send them to admin [at] acute-illness.com.  I can’t guarantee I’ll be able to reply to every question that I get but where possible I’ll aim to cover them in future posts.