This is the network of smart defibrillators circulating in Madrid: they are on EMT buses and they call 112 for you.

In the face of cardiorespiratory arrest, every minute counts. That’s why they are always looking for each other New points for placing a defibrillator It acts as first aid until emergency personnel arrive.

These easy-to-use devices are found in buildings, subways, airports, and even then they are not enough. In addition to placing them at strategic points, they are increasingly stationed at mobile points, e.g Bus or drone.

Madrid’s municipal transport company (EMT) now has 2,200 connected defibrillators in its fleet, one on each bus. Double the novelty, for For deployment and its IoT technology That allows them to sound the alarm before anyone else.

If the driver or passenger removes the support equipment, an automatic warning is activated. This network GPS combines geolocation, Internet of Things (IoT) communication and an alert system to emergency services so that they can know the location of the vehicle without making a manual call to the driver.

The project, developed by Bexen Cardio in collaboration with UnaBiz, aims to convert municipal buses into a cardioprotection network that travels through the city and can provide assistance. Both passengers and anyone suffering from an emergency on the road. The installation was completed in October, according to information provided by the responsible agencies.

A magnet activates the alert

The solution is based on a device Tracker or tracker. The equipment has connectivity for GPS geolocation, defibrillator discharge detection and emergency communications.

The operation begins with a simple physical process. The defibrillator is connected to the bus Via a wire attached to a magnet attached to the tracker. When someone removes the device from its holder, the magnet is released and automatically activates the alarm sequence.

From that moment on, the system receives and transmits Vehicle GPS location With a certain frequency, it sends an alert SMS and places a call to the 112 emergency service. You can receive calls when communication is interrupted.

Thus, the removal of the device initiates an alerting process, which prevents the driver or any other passenger from wasting time searching for the phone, as well as haphazardly communicating the location of the bus, as is usually the case in extreme situations.

GPS is particularly important because it allows Locate the vehicle in an emergency. This is the main technical innovation of the project, because it solves a problem that does not exist in fixed installations with defibrillators: quickly identifying medical equipment that constantly changes position.

The second component is the Internet of Things, known as IoT for its acronym in English. This concept includes physical devices equipped with sensors and connections that can send information to other systems without the need for a human intervention in each communication.

In this case, the tracker transforms medical equipment transported on a bus into a connected device capable of automatically communicating an event and its location. Bexen Cardio I was already using UnaBiz’s Sigfox 0G network To monitor your defibrillator. Based on this experience, specific solutions have been developed for EMT Madrid.

Another requirement was energy autonomy. The tracker bus does not rely on batteries And, according to its developers, it can stay on standby for up to 12 months, saving enough energy to run alarm sequences. This allows the system to operate without connecting to vehicle power and reduces the need to interfere with electrical installations already existing in the bus fleet.

The solution also includes two configurable buttons for calling local emergency numbers, which, according to UnaBiz, facilitates its adaptation to other cardioprotection projects and transport networks.

The city council presented the project in July 2026 and announced that the installation would be completed in October. According to information published by EMT Madrid, the supply, installation, maintenance and event management contract was awarded to Bexen Cardio for 2.9 million euros without VAT.

How a defibrillator works

Tracker equipment solves the problem of detecting and alerting emergency services, but It does not replace the intervention of a caregiver.. A defibrillator is quite easy to use for those who have never had to use it.

Cardiorespiratory arrest is when the heart stops Pumping blood effectively. In some cases, the problem is caused by an electrical disturbance that can be corrected by a shock.

The defibrillator analyzes the heart rhythm through adhesive electrodes placed on the chest and detects if there are any arrhythmias that could lead to shock.

Equipment does not conduct electricity arbitrarily. If it detects a rhythm for which defibrillation is not indicated, it does not recommend shock delivery. If it is deemed necessary, it tells the user how to proceed and when to ensure that no one touches the affected person.

The public use model is designed to Can be used by people without health training Once specialized, they provide auditory instructions that guide the rescuer through the procedure, including placing electrodes and delivering shocks if appropriate.

Thanks to them, cardiopulmonary resuscitation (CPR), which combines chest compressions with other techniques as indicated, continues to be properly applied when healthcare arrives.

EMT fleet defibrillators are ready to help Both adults and small childAccording to project information. Bexen Cardio has provided training to municipal companies and each piece of equipment includes a quick guide to its components and operation of the connected system.

Dynamic equipment network

This initiative changes the usual logic of cardioprotection programs. Instead of relying exclusively on defibrillators installed in specific locations, it takes advantage of a fleet that moves through different neighborhoods and can be closer to an emergency.

The idea of ​​bringing a defibrillator close to the scene of an emergency is not limited to public transport. In Sweden, researchers at the Karolinska Institute conducted the study The use of drones capable of transporting this equipment In the event of possible cardiac arrest, aim to arrive before the ambulance.

In a study published in December 2023 in the scientific journal The Lancet Digital Health, researchers analyzed deliveries during a program run in two regions of Sweden and covered nearly 200,000 residents. Of the 211 alerts for possible cardiac arrest recorded during the study period, drones were deployed on 72 occasions and Defibrillators were distributed in 58 cases.

Of the 55 cases where drone and ambulance arrival times could be compared, the aerial device arrived earlier on 37 occasions, 67% of the total. D The average lead was three minutes and 14 seconds. The study also documented cases where defibrillators delivered by drones were used before medical services arrived.

This is another example of a trend that is increasingly spreading around the world: connecting health resources with systems capable of detecting emergencies, determining where help is needed and quickly mobilizing the appropriate equipment.