Feature | July 20, 2009| Dave Fornell

Prehospital ECGs HaveBig Impact on Door-to-Balloon Times

Remote, EMS transmission of STEMI ECGs leads to earlier cath lab activation.

The LIFENET system can send ECGs to physicians PDA devices so a STEMI diagnosis can be made prior to a patients arrival.

The Philips HeartStart MRx defibrillator/monitor allows paramedics to send 12-lead ECGs to the ED for evaluation and activation of the cath lab prior to a patients arrival.

Zolls E-Series defibrillator/monitors are Bluetooth-enabled to allow paramedics to transmit ECGs using a Bluetooth-enabled cell phone.

Physio-Control's LIFEPAK12

The use of remote, prehospital ECG transmission systems by emergency medical services (EMS) can help quickly identify ST-elevated myocardial infarctions (STEMI) and allow earlier activation of the cath lab prior to the patient’s arrival at the hospital. Users of these systems say earlier diagnosis and cath lab activation is key to significantly reduce door-to-balloon (D2B) times.

In 2006 the American College of Cardiology (ACC) and the American Heart Association (AHA) created a joint recommendation to urge hospitals nationwide to adopt D2B of 90 minutes or less for STEMI patients. Many hospitals are now moving to a more comprehensive model of measuring EMS-to-balloon (EMS2B) times, which accounts for total time elapsed since first responders picked up the patient, given that EMS2B can vary greatly based on distances and possible transfer from hospitals without cath labs.

The companies offering prehospital ECG transmission systems include Physio-Control, Zoll, Philips and General Devices. All of these systems allow EMS to send a 12-lead defibrillator/monitor ECG from the field to a hospital emergency department (ED) so physicians can decide if the patient needs emergency PCI. The systems save time by allowing the cath lab and hospital staff to prepare for the patient prior to their arrival.

Hartford Hospital Slashes D2B with LIFENET

Hartford Hospital implemented the Physio-Control LIFENET system in June 2008. In the past year 61 ECG cases were transmitted by EMS to Hartford’s ED. Paramedics use a Physio-Control LIFEPAK 12, defibrillator/monitor equipped with Bluetooth wireless communications to transmit 12- lead ECGs from the ambulance to the ED while the patient is en route.

“All pure STEMI and qualified ECGs are transmitted to the emergency department and then screened by ED doctors, then they send a message to activate the cath lab,” said Marcin Dada, M.D., associate director, CPC, cardiology administration, Hartford Hospital, in Hartford, Conn. “We did not have any false activations, because we had the ED doctors doing the screening. If EMS was screening we would have more.”

Prior to implementing the system, D2B times started at about 80 minutes, and EMS2B times were well over 90 minutes. Since implementing the system Dr. Dada said off-hour STEMI D2B times dropped to 58 minutes and EMS2B dropped to an average of 93 minutes. During the day when the cath lab is staffed, D2B dropped to about 30 minutes, and EMS2B dropped to 65 minutes.

“It takes a while to work out all the bugs, and you need to get comfortable with the system,” Dr. Dada said.

While the remote ECG transmission technology by itself seems to have had a major impact, Dr. Dada said there is much more to the success at Hartford. He said the success of any STEMI system is based 25 percent on equipment and technology and 75 percent on training, logistics, reports, and EMS training.

“Technology is the first step, but you need a system to build around it to succeed,” he said. “The system itself will not solve all your problems with STEMI care. You can put forward the most advanced technology, but you need the education to go with it.”

For starters, Dr. Dada created an ongoing training program for area paramedics on how and when to use the LIFENET system. Paramedics also get a crash course in cardiac anatomy, what causes AMI, treatment options, and then watch stenting procedures in the cath lab. He said this helped build more of a team mentality with EMS and showed them why their early identification of STEMI is so critical in better patient outcomes. EMS is also trained to identify ST-elevations and STEMI imposters on ECGs. Dr. Dada said this helps narrow the number of ECGs transmitted to the ED to the most likely STEMI candidates.

Paramedics are also asked to fill out a simple STEMI form and put it in a box in the EMS room. Dr. Dada enters this information into a more comprehensive STEMI check list report, which includes patient information, response times, EMS agency, paramedics’ names, and information from both the ED and the cath lab. Prehospital ECGs and post procedure ECGs and pre- and post-procedure angiograms are included in the reports to show the effectiveness of the program and patient outcome. All members of the “team,” including EMS, triage nurses, ED and cath lab personnel, receive an e-mail copy of the reports.

“We want them to understand why this is so important,” Dr. Dada said.

Hartford Hospital wanted to expand its STEMI program to other EMS agencies and hospitals to create a regional STEMI network. However, building this network was not as simple as just purchasing some equipment. Dr. Dada said it takes a lot of coordination between area EMS, fire departments and hospitals. Hartford Hospital helped set up the regional STEMI network with all these groups, but he said politics and competition can easily get in the way of putting together a team that has all its players on the same page.

“If I was doing this again I would have approached other hospitals to create a STEMI system first,” he said, instead of creating a system and asking others to join in later.

Hartford Hospital looked at remote ECG transmission systems from Zoll, Philips, Physio-Control and General Devices. Physio-Control was chosen because the two EMS services Hartford Hospital owns were already equipped with Physio-Control LIFEPAK 12 defibrillator/monitors. These monitors are Bluetooth wireless-enabled for remote transmission of 12-lead ECG via Physio-Control’s LIFENET system. The ECG data can be saved as a PDF, TIFF, GIF or JPEG.

Dr. Dada’s biggest criticism of all the available remote transmission ECG systems is their proprietary software, which makes them incompatible with one another. He said that is a big issue when attempting to set up a regional STEMI system, which may involve several hospitals and EMS organizations that may use different manufactures’ defibrillator/monitors or remote transmission systems. “It’s not about who makes the equipment and who makes the money, its about how many lives these systems can save,” Dr. Dada said.

Philips’ HeartStart MRx Helps Cut D2B

Banner Thunderbird Medical Center in Glendale, Ariz., wanted to reduce its D2B times and adopted Philips HeartStart MRx 12-lead defibrillator/monitors for its STEMI system in 2007.

Laurie Wood, the prehospital coordinator for Banner Thunderbird Medical Center, said the Glendale Fire Department was purchasing new defibrillator/monitors to equip its EMS when the hospital partnered with it to create a regional STEMI network. The Fire Department chose the Philips system and the hospital purchased a server to host the network. Other hospitals in the Glendale area have designated fax machines to receive pre-hospital ECGs rerouted though Banner’s STEMI network server.

The HeartStart MRx defibrillator/monitors are Bluetooth enabled, allowing them to be linked with a paramedic’s Bluetooth-enabled cell phone to transmit a 12-lead ECG via cell transmission, over the Internet, into a receiving station that resides on a server in the emergency room. The ECG is sent as an encyrpted XML file. Wood said the medical center was sold on the system when they saw the quality of a test ECG image arriving through the system. “It was clear and it was the same quality of something we could have printed out here in the hospital,” she said.

Paramedics conduct a 12-lead ECG on all chest pain patients, but only transmit the ECGs that show an ST-elevation or other abnormality to the emergency room. “The chances of it being a false-STEMI is reduced with this system,” she said.

Wood said EMS usually sends the ECG first and then calls the ER, because it may take one to two minutes to transmit. “Usually by the time they call us the ECG has already arrived,” she said. The ER doctors then decide if the cath lab should be activated. Wood said since using the system, the cath lab staff arrived at the same time or just before the patient did in some after-hours STEMI cases.

“The times to get the patient into the cath lab were phenomenal,” she said. Banner Thunderbird witnessed almost a 45-minute reduction in D2B times. In January 2007, the hospital recorded an average time of 134 minutes, but reduced this close to the recommended 90 minutes or less by May 2007.
In the past year, two more area fire departments from the neighboring towns of Goodyear and Peoria purchased HeartStart MRx equipment for its ambulances so they could be a part of the regional STEMI network.

Zoll Offers Low-Cost Option

Jon Cloutier, Zoll Medical Corp. STEMI management product manager, said Zoll is competitive in price compared to Philips and Physio-Control, with system set ups costing less than $3,000.

“In this economy we need to do this as economically as possible,” Cloutier said. “The thing customers look for is the cost of ownership and its ease of use.”

He said Zoll’s E-Series defibrillator/monitors are Bluetooth-enabled so they can transmit 12-lead ECGs using a Bluetooth-enabled cell phone. The call is made to a Zoll server, which translates the ECG data into a PDF. The server can be configured to automatically send the PDF to PDA devices, e-mail or fax machines. Up to 30 different contacts can be added to the system for instant notification. Cloutier said the PDF format was chosen because it can be opened by any PDA or computer, which is not true of proprietary coding or formats such as DICOM or HL7.

He said the system needs to be simple for paramedics, otherwise they will not use it. That was one reason why Zoll uses a cell phone interface. In addition, cell phones are usually replaced every year or so, which allows users to keep up with the latest advances in cell phone technology, Cloutier said. He said the only limitation of the Zoll system is that Bluetooth-enabled iPhones and PDAs will not work for EMS to transmit data, but can be used to receive the ECG.

General Devices Offers Connectivity
General Devices offers the CAREpoint EMS Workstation, a system that integrates and documents all EMS activities taking place in the ED. The system can also receive prehospital 12-lead ECGs from most monitors over radio, cell phone or the Internet.

The company also offers the Rosetta-Lt, a 12-lead data translator, which the manufacturer said allows the transmission of prehospital 12-lead reports from Zoll, Physio-Control and Philips defibrillator/monitors.

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