Pre-Hospital Lung Ultrasound Impact on Diagnosis

Acute heart failure (AHF) is a major reason patients seek emergency care and is a significant public health burden. The ability to differentiate AHF from other etiologies of dyspnea remains a challenge as symptoms and physical exam findings overlap, especially in the pre-hospital setting where diagnostic tools are not readily available. The inability to differentiate AHF from other causes of dyspnea leads to misdiagnosis, delays in diagnosis, and ultimately delays in appropriate treatment. Delays in initiating HF therapies is associated with poor outcomes including higher rates of in-hospital mortality and longer hospital length of stay. Optimizing treatment for AHF in the pre-hospital setting is associated with increased survival and lower rates of hospital re-admission. Thus, accurate diagnosis and early treatment for AHF in the pre-hospital setting remains a critical unmet need. Lung ultrasound (LUS), through assessment of B-lines, allows for an easy and accurate method for detection of pulmonary congestion seen in AHF patients. Although multiple studies have shown LUS is easy to learn, there is a paucity of data assessing clinical impact of LUS in the pre-hospital setting. The investigators hypothesize that the use of LUS by pre-hospital personnel will improve accuracy for detecting AHF in the pre-hospital setting when compared to usual care (no LUS).

Specific Aims: To determine if the use of pre-hospital LUS improves diagnostic accuracy for detecting AHF in patients transported by emergency medical services (EMS) for acute dyspnea when compared to usual care (no LUS).

Study Overview

• Status: Suspended
• Conditions: Acute Heart Failure
• Intervention / Treatment: Other: Usual Care; Diagnostic test: Lung Ultrasound

Detailed Description

Prospective, randomized study using a phased implementation on patients being transported by EMS to the hospital for acute dyspnea. The investigators will include adults (>17yo) with a chief complaint of dyspnea and at least one of the following: bilateral lower extremity edema, orthopnea, wheezing or rales on auscultation, increased work of breathing, tachypnea (RR>20) or hypoxia (oxygen saturation <92%). Patients with fever (>100.4F), systolic blood pressure <90mmHg, those requiring immediate intubation, those found to have ST elevation myocardial infarction on EKG, or pregnant will be excluded. Eligible patients will be enrolled in the pre-hospital setting over a 12-month period. Randomization that will occur at the ambulance level using a stepped wedge cluster randomization trial design. Twenty-six full-time paramedics previously trained in LUS will perform a 2 or 4-view imaging protocol and interpret images in real-time to guide acute management. The diagnosis of AHF on LUS will be defined as bilateral B-lines (>2 B-lines in a zone in each hemi-thorax). A hospital diagnosis of AHF versus not HF will be determined through independent chart review by two blinded physicians and will serve as the criterion standard for final diagnosis. Diagnosis by paramedics, whether LUS was used, and treatment given pre-hospital will be tracked in ESO (an online EMS clinical documentation system). For the primary aim the investigators will compare pre-hospital provider diagnosis to final diagnosis to determine accuracy with and without the use of LUS.

Expected Results: The investigators anticipate the use of prehospital LUS will improve diagnostic accuracy for detecting AHF. This pilot study will set the groundwork for future larger studies assessing the clinical impact of prehospital LUS.

• Study Type: Interventional
• Enrollment (Estimated): 107
• Phase: Not Applicable

Contacts and Locations

Study Locations

• United States
  • Indiana
    • Indianapolis, Indiana, United States, 46203
      • Methodist Hospital

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Adult patients (>17yo) with a chief complaint of shortness of breath.

Exclusion Criteria:

• We will exclude patients with hypotension (SBP <90), an EKG showing ST-segment elevation, fever >100.4F, trauma or who are pregnant.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Diagnostic
• Allocation: Randomized
• Interventional Model: Single Group Assignment
• Masking: None (Open Label)

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Other: Usual Care	Other: Usual Care; Usual care to decide diagnosis and treatment
Experimental: Lung Ultrasound	Diagnostic test: Lung Ultrasound; LUS will be performed and interpreted in real-time to guide acute management.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Diagnostic accuracy of pre-hospital providers for identifying AHF versus not AHF	Pre-hospital providers will diagnose AHF or not HF with and without LUS. Diagnostic accuracy will be determined by comparing pre-hospital diagnosis to hospital diagnosis of AHF versus not AHF through independent chart review.	3 years

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Rate of initiation of AHF therapies in patients with AHF	The rate of AHF therapy initiation in patients who are transported by EMS will be assessed by comparing therapy initiation in patients with and without LUS.	12 months
Timing of AHF therapies in patients with AHF	The timing of AHF therapy in patients who are transported by EMS will be assessed by comparing therapy timing in patients with and without LUS.	12 months

Collaborators and Investigators

• Sponsor: Indiana University

Study record dates

Study Major Dates

• Study Start (Actual): February 9, 2023
• Primary Completion (Estimated): June 1, 2028
• Study Completion (Estimated): June 1, 2028

Study Registration Dates

• First Submitted: June 30, 2022
• First Submitted That Met QC Criteria: July 13, 2022
• First Posted (Actual): July 18, 2022

Study Record Updates

• Last Update Posted (Estimated): June 25, 2025
• Last Update Submitted That Met QC Criteria: June 19, 2025
• Last Verified: June 1, 2025

More Information

Terms related to this study

• Keywords: ultrasound; prehospital
• Additional Relevant MeSH Terms: Cardiovascular Diseases; Heart Diseases; Heart Failure
• Other Study ID Numbers: 15954

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: Yes
• product manufactured in and exported from the U.S.: No