7/25/2019 Smartphone Application for Transmission of ECG Images in Pre-Hospital STEMI Treatment - Poster

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Project Overview

STEMI: S-T segment elevation

myocardial infarction:

A severe heart attack that kills

heart muscle quickly

Every 30 minute delay in treatment

increases 1-year mortality rate by

7.5%

Requires surgery in a specialized lab

that is not always open

UVA Hospital Protocol and Workflow

EMS and physicians work together

to make a pre-hospital diagnosis by

transmitting ECGs from the

ambulance while en route to the

hospital

If the surgical lab is activated while

patient is still in transport, surgery

can begin as soon as possible

Peter Bradley, Michael Durej, Alexander Gessner, Andrew Gould, Imran Khan, Bethany Martin, Marisa Mutty, Erin Myers, and Stephen Patek

Department of Systems and Information Engineering, University of Virginia

Software Design Notes:

Green boxes are layers of the softwarestack

Orange boxes are background processes

that do not require user input Start Pinging consistently checks

the server to see if there is

connectivity. Ping results are kept in a

database and used by the

applications predictive algorithm

Run Prediction Algorithm runs in

parallel to estimate the probability of

a successful transmission based on

the iPhones current location and the

percentage of successful pings

contained in a one-kilometer radius

Update Indicator uses the resultsfrom the prediction algorithm for

visual feedback to the user

The purple box is the user workflow ofcapturing an ECG photo and deciding

whether or not to send it

Question Iteration 1 Iteration 2

Find the application? 4.6 4.9

Start the camera? 4.8 4.9

Align and take a picture of the 12-

lead ECG?

4.3 4.2

View the image before sending? 4.7 4.4

Send the image? 4.8 4.9

Find the setting page? 4.7 5.0

5-point scale: 1 = Very Difficult, 3 = Neither Easy nor Difficult, 5 = Very Easy.

Screen #2

After a user takes the

picture, the confirmation

screen appears

If the picture is not

satisfactory, the user can

retake the picture

If the picture is

satisfactory, the user

presses send to initiate

transmission

The user can also exitcapture mode and go

back to the home screen

Screen #1

Automatically opens the

camera tab

Green check indicates

there is a 90% chance

that a transmission will

succeed (threshold is

adjustable in settings)

On-screen instructionsguide EMS how to align

the ECG strip

Users press Click toBegin when they are

ready to take the picture

Screen #3

Transmission status

screen allows users to

know a transmission is

taking place

Displays elapsed time

since initiation

Displays maximum time

allowed for attempting

to transmission

(adjustable in settings)

When a transmissionsucceeds or fails, the

user is alerted on

screen and with sound

iPhone Operating System

Our Application

Camera View Controller

ECG PhotoCapture

Workflow

RunPrediction

Algorithm

UpdateIndicator

StartPinging

Problem Definition

Currently, ambulances that serve the

UVA hospital are equipped with

proprietary systems that transmit

ECGs over voice networks via modem.

These systems have several

drawbacks:

Expensive upfront and monthly

costs ($30,000+ per ambulance)

Low reliability (estimates of 20-

50% of transmissions are

successful)

Zero feedback for EMS

How likely is a transmission at a

given point in time?

Has the transmission arrived at

the hospital?

Lack of information can cause

confusion over when an EMS provider

should attempt to contact the

hospital. Any delay in diagnosis is

detrimental to the patient.

Software Design Stack Transmission and Data CoverageCoverage Map Notes:

Provided by AT&T

Darkest blue areas on themap represent 4G LTE

coverage Light blue areas represent 2G

and 3G coverage.

White areas have zero datacoverage

Transmission Data:

Green points on the mapshow where test

transmissions sent to a UVA

server successfully

Red points on the map show

where test transmissions

failed to send to a UVA server

Emergency Responder User Experience

Results We have created an application that is inexpensive, informative, and user-centered while

integrating with EMT protocol.

During testing, users were asked to complete a series of tasks and to rate how easy it was tocomplete these tasks on a scale from 1-5

Testing results (table on right) reveal that users generally found the application easy to use Future work includes:

Transmission testing in many locations throughout Charlottesville to create an ROC

curve comparing the rate of true vs. false positives

Implementing the system at the UVA hospital, on a server protected by firewall.

Training EMS personnel Creating a business plan to market the application in other areas

AcknowledgmentsWe would like to thank Dr. David Burt,

director of the Chest Pain Center and

cardiologist at the University of

Virginia Emergency Medicine

Department, as well as Dr. Mark

Sochor, Associate Professor of

Emergency Medicine at University of

Virginia. Their technical expertise and

leadership were crucial to the project.

Smartphone Application for Transmission of

ECG Images in Pre-Hospital STEMI Treatment

Solution

An iPhone app providing an EMT the ability to:

Snap a photo of an ECG printout

Compress and transmit the image

Assess whether the transmission of the image at that time will be

succesfully received within two minutes