Predict Sepsis; the Predictive Value of Bedside Measures in the Ambulance

Introduction

Sepsis affects at least 19 000 people in Sweden each year. Despite being a time critical condition with a high mortality, sepsis is often not identified in a timely fashion. The current study aims to identify predictors of sepsis in the ambulance setting. Early treatment is a cornerstone in sepsis. Time to treatment in the emergency department (ED) has been shown to be shortened by identification of the septic patient in the ambulance. Identification of the septic patient in the ambulance may also move the treatment to the prehospital setting.

At present, identification is dependent on the suspicion of sepsis and by health care professionals applying clinical judgment. Traditionally, the definition of sepsis has been based on the presence of infection and a minimum of two SIRS criteria (Systemic Inflammatory Response Syndrome), which have, however, been shown to be both un-sensitive and non-specific. The investigators have in previous studies proved proof of principle that a screening tool increases the identification of the septic patient and is superior to clinical judgment among both ambulance personnel and ED doctors. Moreover, these studies also illustrate that current screening tools do not identify all septic patients.

Information from the patients' medical history has not previously been incorporated in a screening tool. The investigators have previously identified keywords related to the septic patients' medical history as presented to the emergency medical services (EMS). Eight keywords showed a prevalence exceeding 20% for all septic patients, and examples were gastrointestinal symptoms and a history of abnormal temperature. However, the specificity of these keywords with respect to sepsis remains to be determined.

Also, point of care blood tests may add value in sepsis identification in the ambulance when combined with other measures. Glucose is currently measured by the Swedish EMS. Lactate testing is standard in Swedish EDs, but yet not in all ambulance services, and is used as a marker of hypoperfusion and response to treatment in sepsis. Soluble urokinase-type plasminogen activator (suPAR) has been shown to be a prognostic marker in sepsis. Heparin-binding protein (HBP) is a promising biomarker and as an early indicator of circulatory failure in sepsis. To date, no studies have analyzed the added value of suPAR or HBP to history and vital parameters.