title: Prehospital factors associated with an acute life-threatening condition in non-traumatic chest pain patients - A systematic review.
abstract: BACKGROUND
  Chest pain is a common symptom among patients contacting the emergency medical services (EMS). Risk stratification of these patients is warranted before arrival in hospital, regarding likelihood of an acute life-threatening condition (LTC).
  
  
  OBJECTIVE
  To identify factors associated with an increased risk of acute LTC among patients who call the EMS due to non-traumatic chest pain.
  
  
  METHODS
  Several databases were searched for relevant articles. Identified articles were quality-assessed using the Scottish Intercollegiate Guidelines Network checklists. Extracted data was analysed using a semi-quantitative synthesis evaluating the level of evidence of each identified factor.
  
  
  RESULTS
  In total, 10 of 1245 identified studies were included. These studies provided strong evidence for an increased risk of an acute LTC with increasing age, male gender, elevated heart rate, low systolic blood pressure and ST elevation or ST depression on a 12-lead ECG. The level of evidence regarding the history of myocardial infarction, angina pectoris or presence of a Q wave or a Left Bundle Branch Block on the ECG was moderate. The evidence was inconclusive regarding dyspnoea, cold sweat/paleness, nausea/vomiting, history of chronic heart failure, smoking, Right Bundle Branch Block or T-inversions on the ECG.
  
  
  CONCLUSIONS
  Factors reflecting age, gender, myocardial ischemia and a compromised cardiovascular system predicted an increased risk of an acute life-threatening condition in the prehospital setting in cases of acute chest pain. These factors may form the basis for prehospital risk stratification in acute chest pain.
authors.affiliation: Department of Ambulance and Prehospital Care, Region Halland, Sweden; School of Health Sciences, Department of Nursing, Jönköping University, Jönköping, Sweden. Electronic address: kristoffer.wibring@regionhalland.se.
authors.forename: Kristoffer
authors.initials: K
authors.lastname: Wibring
authors.affiliation: The Pre-hospital Research Centre of Western Sweden, Prehospen, University College of Borås, Borås, Sweden.
authors.forename: Johan
authors.initials: J
authors.lastname: Herlitz
authors.affiliation: School of Health Sciences, Department of Nursing, Jönköping University, Jönköping, Sweden.
authors.forename: Lennart
authors.initials: L
authors.lastname: Christensson
authors.affiliation: Department of Medicine, Region Halland, Sweden.
authors.forename: Markus
authors.initials: M
authors.lastname: Lingman
authors.affiliation: The Pre-hospital Research Centre of Western Sweden, Prehospen, University College of Borås, Borås, Sweden.
authors.forename: Angela
authors.initials: A
authors.lastname: Bång
mesh_terms: D054058:Acute Coronary Syndrome / Q000175:diagnosis* / Q000453:epidemiology* / Q000628:therapy; D000208:Acute Disease; D002637:Chest Pain / Q000175:diagnosis* / Q000453:epidemiology* / Q000628:therapy; D004632:Emergency Medical Services / Q000639:trends*; D006801:Humans; D012307:Risk Factors
keywords: Acute coronary syndrome; Chest pain; Emergency medical services; Prehospital; Risk assessment