Paramedic identification of acute pulmonary edema In a metropolitan ambulance service

Abstract

Introduction. Acute pulmonary edema (APE) is a commoncause of acute dyspnea. In the prehospital setting, it is oftendifficult to differentiate APE from other causes of shortnessof breath (SOB). Radiography and echocardiography aid inthe identification of APE but are often not available. There islittle information on how accurately ambulance paramedicsidentify patients with APE. Objectives. This study aimed to1) describe the prehospital clinical presentation and managementof patients with a clinical diagnosis of APE and 2) comparethe accuracy of coding of APE by paramedics againstthe emergency department (ED) medical discharge diagnosis.Methods. This study included a retrospective cohort ofall patients who had episodes identified as APE by ambulanceparamedics and were transported to a metropolitanhospital ED in 2011. Two databases were used: an ambulancedatabase and the Emergency Department InformationSystem. The ED medical discharge diagnosis (using InternationalStatistical Classification of Diseases and Related Problems,10th Revision, Australian Modification [ICD-10-AM]codes) was used as the comparator with paramedic-assignedproblem codes for APE. The outcomes for the study were thepositive predictive value, i.e., the proportion of patients identifiedas having APE in the ambulance database who alsoof paramedic identification of APE, i.e., the proportion of patientswith an ED discharge diagnosis of APE that were correctlyidentified as APE by the ambulance paramedics. Results.Four hundred ninety-five patients were transported toan ED with APE identified by the paramedics as the primaryproblem code. Shortness of breath, crepitations, high systolicblood pressure, and chest pain were the most common presentingsigns and symptoms. Pink frothy sputum was rare(3% of patient episodes of APE). One hundred eighty-six patientsreceived an ED discharge diagnosis of APE, i.e., a positivepredictive value of 41%. Of 631 ED presentations withAPE, paramedics identified 186, i.e., a sensitivity of 29%.Conclusion. Acute pulmonary edema is difficult to identifyin the prehospital setting because of the variability inthe signs and symptoms associated with this condition. Improvedidentification of APE is essential in the initiation ofappropriate and timely care. Ambulance paramedics need tobe aware of such variability when considering patients whomay be suffering from APE