The goal of this prospective nonrandomized study is to determine if a lung ultrasound exam improves diagnosis of respiratory distress in patients being treated by Emergency Medical Services. The main question it aims to answer is whether ultrasound use increases likelihood of correctly diagnosing heart failure. Additional questions include:

• How well can paramedics obtain and interpret ultrasound images?
• How does ultrasound use change treatment received by patients?
• How does ultrasound use impact patient outcomes? Participants will receive a lung ultrasound exam, but otherwise receive standard evaluation and care. Patients who receive ultrasound will be compared to those who did not receive ultrasound for logistical reasons and patients from before the use of ultrasound. Ultrasound will not be withheld from any patient for the purposes of the study.

Inclusion Criteria:

• Patient treated by Emergency Medical Services
• Complaint of dyspnea

At least one of the following:

• Oxygen saturation <94% on room air
• Abnormal lung sounds
• Increased work of breathing
• Pedal edema
• Orthopnea

Exclusion Criteria:

• Pediatric patients (<18)
• Traumatic etiology
• Cardiac arrest at any point prehospitally
• No ultrasound-trained paramedic involved in patient's care

Data that can be linked to individual patients will not be shared due to patient confidentiality.