Prehospital Lung Ultrasound: Impact on Diagnosis and Management in Patients with Acute Heart Failure

Background/Objective: In the United States, one million hospitalizations occur each year due to acute heart failure (AHF), with a one-year mortality rate of 27%. Recent literature suggests that early diagnosis and treatment is associated improved prognosis. We investigated diagnostic accuracy prehospital paramedic-performed lung ultrasound (LUS) its impact on initial patients AHF.
 Methods: Paramedics, previously trained in LUS, performed 4-zone LUS protocol evaluate for presence or absence pulmonary edema. Per protocol, bilateral B-lines was AHF included nitroglycerin. Inclusion criteria were (>18 years old) shortness breath at least following: lower extremity edema, orthopnea, wheezing rales auscultation, increased work breathing, tachypnea (RR>20) hypoxia (oxygen saturation <92%). Patient data collected hospital setting evaluated by 2 separate physicians determine final diagnoses AHF. Paramedic analyzed image quality, diagnosis, treatment.
 Results: Prehospital 27 meeting inclusion criteria. Diagnostic yielded sensitivity 66.7% (95% CI 29.9%-92.5%) specificity 100% 81.5%-100%). Of 9 AHF, 3 not correctly identified despite having (33%) received Median quality 4 (range 3-5) 5-point scale.
 Conclusion: highly specific moderately sensitive which an improvement over without use (prior showing 14% sensitivity, 98% specificity). slightly initiation HF therapy (33% vs 28% reported). More training needed improve increase therapies setting.