Sepsis, also known as blood poisoning, is a severe infection that can cause organ failure. If not identified and treated quickly, the condition can be fatal.

A common condition in acute medicine

Sepsis is a frequent problem in acute medicine, whether you work outside or inside a hospital. Sepsis-related causes account for approximately 1% of all hospital admissions and consequently a significant proportion of hospital bed-days (1). It is also a common cause of intensive care stays, as sepsis often leads to multiple organ failure.

High mortality in sepsis

Sepsis is a deadly condition with an in-hospital mortality of over 10%. Mortality rises to over 40% if the patient develops septic shock (2).

Incidence is increasing

The number of patients with sepsis also appears to be increasing, which may be linked to factors such as a growing number of elderly and multi-morbid individuals, more immunomodulatory treatment, and increasing antibiotic resistance (2).

Early treatment saves lives

In other words, sepsis is a very serious condition with higher mortality than, for example, severe myocardial infarction (3–8). Research shows that early identification of sepsis and initiation of appropriate treatment improves the patient's prognosis and survival (9,10).

What is sepsis?

So, what is sepsis? Sepsis is defined as a life-threatening organ dysfunction caused by a dysregulated host response to infection (2). The origin of sepsis, in other words, is an infection accompanied by a large and inappropriate inflammatory response. Instead of the body's defense mechanisms fighting the infection locally where it is, the immune response becomes systemic and spreads throughout the body. The regulatory mechanisms that should have stopped this inappropriate immune response fail, leading to a self-perpetuating, uncontrollable, and life-threatening organ failure.

This organ failure is defined in the sepsis definition as an acute increase of ≥ 2 points in a scoring tool called SOFA (2). SOFA score is mainly used in intensive care units and grades organ dysfunction from 1 to 4 (see table).

SIRS criteria

To help healthcare personnel outside intensive care units define, and crucially, recognize sepsis, simpler tools such as qSOFA, SIRS, and NEWS have been adopted.

The SIRS criteria were previously part of both the definition and diagnosis of sepsis. However, the SIRS criteria often captured other inflammatory conditions. They were considered too sensitive and not specific enough, and so they were abandoned (2).

Although the SIRS criteria are no longer included in the definition of sepsis, they are still useful in assessing inflammatory conditions in patients.

qSOFA

After the new definition of sepsis in 2016, extra focus was placed on the SOFA score as the definition of organ dysfunction. It is defined by an acute increase in SOFA score ≥ 2 points.34 As SOFA criteria are cumbersome to use in prehospital and acute settings, the use of quickSOFA (qSOFA) was recommended (2).

qSOFA scores are easy to use and only require a clinical examination, which makes them useful prehospital and in acute settings. However, studies have shown mixed results on qSOFA's ability to predict mortality, and in the latest version of the international guidelines, the Surviving
Sepsis Campaign, it has been recommended not to use qSOFA alone (9).

Sources:

1. Knoop ST, Skrede S, Langeland N, Flaatten HK. Epidemiology and impact on all-cause mortality of sepsis in Norwegian hospitals: A national retrospective study. Brakenridge S, ed. PLOS ONE. 2017;12(11):e0187990. doi:10.1371/journal.pone.0187990

2. Singer M, Deutschman CS, Seymour CW, et al. The Third International Consensus Definitions for Sepsis and Septic Shock (Sepsis-3). JAMA. 2016;315(8):801. doi:10.1001/jama.2016.0287

3. Tobbia P, Brodie BR, Witzenbichler B, et al. Adverse event rates following primary PCI for STEMI at US and non-US hospitals: three-year analysis from the HORIZONS-AMI trial. EuroIntervention JEur Collab Work Group Interv Cardiol Eur Soc Cardiol. 2013;8(10):1134-1142. doi:10.4244/EIJV8I10A176

4. Jernberg T, Johanson P, Held C, et al. Association between adoption of evidence-based treatment and survival for patients with ST-elevation myocardial infarction. JAMA. 2011;305(16):1677-1684. doi:10.1001/jama.2011.522

5. McManus DD, Gore J, Yarzebski J, Spencer F, Lessard D, Goldberg RJ. Recent trends in the incidence, treatment, and outcomes of patients with STEMI and NSTEMI. Am J Med.2011;124(1):40-47. doi:10.1016/j.amjmed.2010.07.023

6. Bagai A, Lu D, Lucas J, et al. Temporal Trends in Utilization of Cardiac Therapies and Outcomes for Myocardial Infarction by Degree of Chronic Kidney Disease: A Report From the NCDR Chest Pain-MI Registry. J Am Heart Assoc. 2018;7(24):e010394. doi:10.1161/
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7. Roe MT, Messenger JC, Weintraub WS, et al. Treatments,Trends, and Outcomes of Acute Myocardial Infarction and Percutaneous Coronary Intervention. J Am Coll Cardiol. 2010;56(4):254-263. doi:10.1016/j.jacc.2010.05.008

8. Rosamond WD, Chambless LE, Heiss G, et al. Twenty-two-year trends in incidence of myocardial infarction, coronary heart disease mortality, and case fatality in 4 US communities, 1987-2008. Circulation. 2012;125(15):1848-1857. doi:10.1161/
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9. Evans L, Rhodes A, Alhazzani W, et al. Surviving Sepsis Campaign: International Guidelines for Management of Sepsis and Septic Shock 2021. Crit Care Med. 2021;49(11):e1063-e1143. doi:10.1097/CCM.0000000000005337

10. Weiss SL, Peters MJ, Alhazzani W, et al. Surviving SepsisnCampaign International Guidelines for the Management of Septic Shock and Sepsis-Associated Organ Dysfunction in Children. PediatrCrit Care Med. 2020;21(2):e52-e106. doi:10.1097/PCC.0000000000002198