title: The use of gastrointestinal cocktail for differentiating gastro-oesophageal reflux disease and acute coronary syndrome in the emergency setting: a systematic review.
abstract: BACKGROUND
  Differentiating acute chest pain caused by myocardial ischaemia from other, potentially more benign causes of chest pain is a frequent diagnostic challenge faced by Emergency Department (ED) clinicians. Only 30% of patients presenting with chest pain will have a cardiac origin for the pain, and gastro-oesophageal disorders are one of the common sources of non-cardiac chest pain, yet remain clinically difficult to differentiate from cardiac pain.
  
  
  OBJECTIVE
  A systematic review of the literature was conducted to locate and evaluate clinical trials comparing the use of an oral gastrointestinal (GI) cocktail (oral viscous lidocaine/ antacid ± anticholinergic) to standard diagnostic protocols (serial electrocardiograms (ECGs), serial biomarkers, imaging and/ or provocative testing) to differentiate emergency patients presenting with acute chest pain caused by gastro-oesophageal disease from those with other aetiologies.
  
  
  METHODS
  Studies were identified by searching electronic databases, scanning reference lists of articles, and searching clinical trial databases for relevantly currently registered trials. The search included PubMed (1966 - present), Embase (1980 - present) and Cochrane Central Register of Controlled Trials (CENTRAL). The identified studies were evaluated with a modified QUADAS tool.
  
  
  RESULTS
  A total of four studies were identified for inclusion in the review. Studies were of low methodological quality with heterogeneous results. There were no adequately powered and appropriately designed studies identified.
  
  
  CONCLUSIONS
  Current diagnostic protocols for Acute Coronary Syndrome (ACS) revolve around early and serial ECG monitoring and cardiac biomarker testing, imaging and careful clinical examination. In patients with chest pain and suspected ACS, the use of a GI cocktail compared with standard diagnostic protocols (serial ECG and biomarkers and provocative testing or imaging) is not proven to improve accuracy of diagnosis, and cannot reliably exclude myocardial ischaemia.
authors.affiliation: Heart and Lung Institute, The Prince Charles Hospital, Brisbane, Queensland, Australia; The University of Queensland, School of Medicine, Brisbane, Queensland, Australia. Electronic address: samuel.chan@uqconnect.edu.au.
authors.forename: Samuel
authors.initials: S
authors.lastname: Chan
authors.affiliation: Heart and Lung Institute, The Prince Charles Hospital, Brisbane, Queensland, Australia; The University of Queensland, School of Medicine, Brisbane, Queensland, Australia.
authors.forename: Andrew P
authors.initials: AP
authors.lastname: Maurice
authors.affiliation: The University of Tasmania, School of Medicine, Sydney Campus, Australia; The Distributed Research in Acute and Emergency Medicine (DREAM) Collaboration, Sydney, Australia.
authors.forename: Suzanne R
authors.initials: SR
authors.lastname: Davies
authors.affiliation: Heart and Lung Institute, The Prince Charles Hospital, Brisbane, Queensland, Australia; The University of Queensland, School of Medicine, Brisbane, Queensland, Australia.
authors.forename: Darren L
authors.initials: DL
authors.lastname: Walters
mesh_terms: D054058:Acute Coronary Syndrome / Q000150:complications / Q000175:diagnosis*; D000284:Administration, Oral; D000779:Anesthetics, Local / Q000008:administration & dosage; D000863:Antacids / Q000008:administration & dosage; D015415:Biomarkers / Q000097:blood; D002637:Chest Pain / Q000209:etiology*; D018680:Cholinergic Antagonists / Q000008:administration & dosage; D003937:Diagnosis, Differential; D004338:Drug Combinations; D004562:Electrocardiography; D004636:Emergency Service, Hospital; D005764:Gastroesophageal Reflux / Q000150:complications / Q000175:diagnosis*; D006801:Humans; D008012:Lidocaine / Q000008:administration & dosage
chemical_list: D000779:Anesthetics, Local; D000863:Antacids; D015415:Biomarkers; D018680:Cholinergic Antagonists; D004338:Drug Combinations; D008012:Lidocaine
keywords: Acute coronary syndromes; Cardiac; Chest pain; Cocktail; Gastrointestinal; Ischaemia