Unit Chief Pilot Mario Carretta gives an insight into the tasking and deployment of our Helicopter Emergency Medical Service (HEMS) and highlights the great work of the HEMS desk team.

A lifeline in emergency care

Dorset and Somerset Air Ambulance (DSAA) is a vital part of the Helicopter Emergency Medical Services (HEMS) network within the South Western Ambulance Service NHS Foundation Trust (SWAST). This network includes five air ambulance charities - DSAA, Cornwall, Devon, Great Western, and Wiltshire - that collaborate to deliver critical emergency care across the region.

Coordinated deployment from the HEMS Desk

A dedicated HEMS desk is located in ambulance control in Exeter and they are responsible for deploying air ambulances across the south west. This desk is funded by the five air ambulance charities and up to two people are on duty throughout the combined operational hours of the six aircraft (7am – 3am).

Throughout their shift, the HEMS desk team monitor 999 calls, to see if any of the patients would benefit from the enhanced or critical care that we provide. Additionally, our ambulance service colleagues working on the road may contact the HEMS desk if they believe their patient requires additional pre-hospital care.

Seamless communication and deployment

Once the HEMS desk is aware that we are required, they’ll contact us directly. However, if we are already committed, they will contact the next nearest air ambulance in the region. This is why we are sometimes deployed to our neighbouring counties and visa-versa.

Preparing for day and night operations

At the start of each shift, we brief fully and cover items such as the weather, hazards and aircraft details. During the day, that enables us to walk to the aircraft once the necessary details have been received and we aim to be airborne within 5-7 minutes of the initial call. At night, there is a requirement for more in-depth planning and we will choose at least two landing sites as close as possible to the incident. We choose at least one spare site, just in case the primary option has livestock, crops, or anything else that could stop us landing not shown via a satellite image. At night, we aim to launch within about 10 minutes of receiving a call.

Dynamic tasking and safety monitoring

Tasking by the HEMS desk, is based mainly on details gathered from the initial 999 call. Sometimes the land crews will arrive first and find that the patient is not as injured or ill as first thought, so the desk will stand us down, making us available for other patients who need the specialist care that DSAA provide.

We are often re-tasked in the air, usually via ACANS and can fly directly there during the day. At night, we may need to set up a holding pattern, to allow us to plan further, before heading in the direction of the incident. The desk also monitors our progress on ACANS via an aircraft symbol, which means that they fulfil a safety function too. They would be our first point of contact in an emergency, when normal air traffic services are not available; after 2200hrs, the majority of our local airfields no longer provide a service.

Emergency response across the South West

Dorset and Somerset Air Ambulance, in collaboration with the HEMS network, plays an essential role in delivering life-saving care. Through innovative technology, seamless communication, and efficient tasking, DSAA ensures patients across the south west receive the critical support they need when it matters most.