The world’s largest ambulance (and the world’s smallest X-ray unit)

May 14, 2009 "Scalpel please! " is a sentence that might in future not only be heard in a hospital operating theatre, but also in one of the three new, large-capacity Mercedes-Benz ambulances handed over to the Centre of Ambulance Services of the Government of Dubai. From now on, it is the hospital that comes to the patient in Dubai. The clinic buses were ordered so that rapid medical assistance can be rendered in the event of major emergencies with large numbers of injury victims. As is well-known, the survival chances of very seriously injured persons in large measure depend on rapid first treatment, and this is the purpose of the large-capacity ambulances.

Particularly owing to the chaotic traffic conditions in and around disaster areas, there are often delays in getting patients to a hospital. Equally often, there are an insufficient number of ambulances available. While a two-man crew is normally only able to care for one patient in an emergency ambulance, up to 20 persons can receive care from four specialist personnel in the Mercedes-Benz large-capacity ambulance. These new emergency vehicles now offer the unique possibilities of a fully equipped, mobile clinic with an intensive-care unit and an operating theatre.

These vehicles now entering service on the roads of Dubai are nothing short of mobile superlatives. On the basis of the Mercedes-Benz Citaro regular service bus and the Citaro G, the vehicle conversion specialists Gebr. Heymann GmbH working with the international research and consultancy company " Von Bergh Global Medical Consulting " have developed vehicles that meet the very highest medical requirements. It is not without a measure of pride that the companies concerned describe them as the world’s largest ambulances. A tour of these buses quickly shows that this is no exaggeration.

Three variants have been produced: Bus variant A is designed as a mobile intensive care unit, variant B for the large-scale treatment and transport of medium to slightly injured patients, and variant C as a combination of the two. This variant alone has enough treatment and transport capacity for more than 80 patients.

There are three observation bays in the interior of the intensive-care bus, and one of these can be converted into a fully-functioning operating theatre. The technical equipment used to monitor patients covers the entire range, including an ECG and – as a genuine world first – an InSpectra shock monitor with which the oxygen saturation in tissue-matter can be monitored by simply placing a sensor on the palm. This development breakthrough is able to warn doctors of the onset of shock minutes before it occurs, so that appropriate countermeasures can be taken. Internal bleeding can also be detected and monitored with this unit.

Further diagnosis is possible using X-rays and ultrasonic equipment. The Mercedes-Benz large-capacity ambulances are equipped with the world’s smallest X-ray unit, whose output is so low that precautions such as lead screens are unnecessary. The X-ray images are shown on a computer monitor in real time. During treatment the patient lies on an operating table which is lit by a fully-fledged operating theatre lights. A wide variety of operations and treatments can be carried out using disposable instrument sets. The Mercedes-Benz large-capacity ambulances are also well-equipped if the need for a caesarian birth arises. Not only are the necessary obstetrical instruments on board, but the newborn or premature baby can also be given the proper care in an incubator.

The onboard supply of oxygen for patients posed a particular challenge, as this is a major factor in the treatment of injured persons. Each of the buses carries 12,000 litres of oxygen, ensuring a reliable supply for up to three days. The gas is fed to the different seating areas by separate lines. Pressing a button causes oxygen masks to fall from special holders, and the oxygen flow to each mask can be individually controlled.An operator station at the front of these vehicles allows external communication by telephone, radio, internet and fax. A laptop is included in the equipment, as is a large LCD monitor which enables the individual areas in the large-capacity ambulance to be monitored.

Converting the Mercedes-Benz Citaro buses into ambulances took around 700 hours. In addition to widest possible range of medical functions, great attention was paid to quality of craftsmanship and visual appearance. The mediboards, i.e. the walls to which the medical equipment is attached, are in a carbon-fibre look, and brushed stainless steel is used in numerous places. The buses are also the only large-capacity ambulances to feature roll-in systems for stretchers such as those used by paramedical services, so that patients can be rolled into the vehicle in a prone position.

The buses can also be equipped with a rear-mounted equipment box containing generators, tents for the treatment of more injury victims, decontamination systems with the relevant protective suits and an oxygen concentrator. This system enables oxygen to be produced for several weeks without recourse to gas suppliers.

The Mercedes-Benz Citaro regular service bus and the Citaro G were used as the basis for the large-capacity ambulances. The Citaro is powered by clean diesel engines, natural gas engines and – as a fuel cell bus – the drive system of tomorrow. It is the backbone of urban public transport, and an alternative to light-rail systems in the guise of the CapaCity bus. The modular design of the Citaro provides a high degree of flexibility, both in terms of operating profiles and the production process. This not only allows the use of different drive systems, but also forms the basis for numerous special versions. Special conversions into fire service command vehicles, police buses, mobile television studios or large-capacity emergency vehicles for events are by no means rare.

The large-capacity ambulances for Dubai are two buses with a length of 12 metres and an articulated bus with a length of 18 metres. Comprehensive corrosion protection even under the extreme operating conditions of the Middle East is ensured by cathodic dip priming.

The two solo vehicles are powered by an OM M 457 (h)LA engine with an output of 220 kW (299 hp) and an OM 457 (h)LA with an output of 260 kW (354 hp). Specifically for the hot conditions in Dubai, both buses feature high-performance air conditioning systems, and air curtains at the doors prevent warm air from entering and cool air from escaping. Vehicle safety is ensured by the Electronic Braking System (EBS), disc brakes all-round, ABS and side impact protection.