What is sepsis?

Sepsis has been known by a lot of different names in the past, from blood poisoning and septicaemia to ‘blood rot’ back in the 11th Century. But these terms all refer to the same dangerous condition, where the body’s exaggerated reaction to an infection causes severe collateral damage to its own organs and tissues. It’s a medical emergency, and the WHO estimates that it kills around 11 million people each year. Thankfully, prompt diagnosis and treatment can turn the tables on the condition. Eva Higginbotham spoke to Suzanne, a sepsis survivor, to hear her story...

Eva - Suzanne was a healthy 40 year old woman who, like many of us, seemed to catch a bit of a cold in the stressful run-up to Christmas three years ago.

苏珊娜——我只是开始变得更糟,更糟的是,一个nd I thought I was developing the flu. It came round to Christmas day and I was feeling really, really unwell but I managed to get to my family and my parents' house to spend an hour with them, when I was meant to be spending the whole day. I had to go home, just feeling really unwell. I was feeling terrible. Couldn't sleep. At four o'clock in the morning I was Googling symptoms about flu and for some reason thought maybe it's not flu, maybe I've got pneumonia. Quite quickly realised that my symptoms were much more like pneumonia rather than influenza. The advice was you must go and see your GP as soon as possible.

Eva - By this point she was so weak her husband had to drive her the hundred meters to her GPS office for her appointment the next morning

苏珊娜——她看上去的确有点担心,我认为,when she saw me, but she put their sensor on my finger that measures your blood oxygen. It was in the 80 something percent, which is not good at all. I very clearly remember her saying, "I don't mean to alarm you, but I will be calling an ambulance and we'll be taking you to the Queen Elizabeth. You're not very well. You need to get to hospital as soon as possible."

Eva - Although Suzanne remembers the GP appointment, her memory pretty much goes blank for the next two weeks. She's had to rely on friends and family's descriptions of what happened next. She was rushed to hospital and put in intensive care before being put on a ventilator with her family waiting outside.

Suzanne - The consultant came back and said that things had spiralled out of control. I guess at some point in all of that, that's when it became apparent that I had sepsis. I don't really know at what point it was first diagnosed. I was on the ventilator, but my body had just kind of gone out of control and the oxygen that I was receiving through the ventilator wasn't enough to sustain me, to keep me going...

So, let’s explore what sepsis actually is, and how doctors treat it. Chris Smith spoke to Colin Begg from the Paediatric Intensive Care Unit in Glasgow...

Colin - The straight medical definition is essentially where your body gets an infection and then your immune system's reaction to that infection causes damage to your organs.

Chris - And how would a person who's going down that path know it's happening to them?

Colin - That's the million dollar question Chris. Really the initial signs of sepsis can be quite nonspecific. What we as medical professionals try to do is separate those people who have sepsis from those people who perhaps just have a bad infection. All sepsis starts with an infection and it's trying to identify those people who are going to progress on to sepsis. That is probably the hardest part of our job at times.

Chris - How quickly is it clear that someone is on that slippery slope from just what could be a trivial infection for most people to life-threatening overwhelming sepsis in that person?

Colin - It can be very fast. Sepsis is one of the few conditions in the modern world that can kill a healthy adult in a matter of hours. Globally it's still the number one cause of preventable death. Often we can get an idea within minutes by looking at somebody's vital signs and certain other simple tests that they are progressing to a more severe case of sepsis.

Chris - When we make the diagnosis, do we actually know, right this person's definitely got sepsis? Is that more a judgment call on the part of a doctor like you, who's putting together various measures and thinking, this person's not going in the right direction, they're heading towards this situation? Or are there some clear indicators this person has got sepsis?

Colin - There are clear indicators, but those can be quite non-specific. What I teach my registrars is, can they say for certain that this is not sepsis? Because the treatment is really broadly simple measures. By initiating those measures you can stop the cascade of sepsis very early and prevent people progressing to multiorgan failure, which is what you want to do. Really it's almost a 'shoot first ask questions later' approach a lot of the time in terms of the simple things we deliver like - oxygen, antibiotics, intravenous fluids. Then it's a question of going back and constantly reassessing the patient. It's one of those situations where expertise can be key, bringing a senior person in to see the patient can often make a difference.

Chris - Are there certain groups of patients that are particularly vulnerable to this happening that we need to watch out for?

Colin - Yeah. Like many diseases. Sepsis affects disproportionately the very young and the very old, particularly the preschool toddler/infant group and also the elderly, people over the age of 70, and people that have got any sort of immune problems. Patients who are immunosuppressed because of cancer, HIV, rheumatological disease, they're all more vulnerable to sepsis than the general.

Chris - Are there any particular diseases that we associate with sepsis happening more frequently? If one person is diagnosed with them we know to watch out?

Colin - Particularly simple things like pneumonia, a chest infection, or certain types of skin infection like cellulitis, certain urine infections. All of those can progress towards sepsis fairly easily depending on the bug that is involved.

Chris - How long does it take for a person to turn the corner and then recover after a bout of sepsis?

Colin - Again, that varies. It very much depends on the person's premorbid state. If they were healthy beforehand then generally they will recover quicker but that is not always the case. Sepsis can take a terrible toll, particularly the multiorgan failure aspect of it. If you spend a fortnight in ICU on support, that takes a toll on your muscle strength, on your physical ability to do simple things like move and breathe. It can take a long process of rehabilitation before you get back to your normal self and some people say they never fully recover.

Chris - What fraction of people don't make it?

Colin - Globally, the fatality from sepsis varies. In the UK it's probably in the order of 15 to 25% mortality, which is high. That's in adults. In my own field in paediatrics our baseline mortality is in the order of 3%. For every hundred people who come into children's intensive care; sadly three of them will not make it through. For sepsis the fatality rate, the mortality is much higher than that, probably in the order of about 10 to 15%.