[Primary care hospital for a mass disaster MANV IV. Experience from a mock disaster exercise]

In Hannover and in nationwide contingency plans there are clear instructions for the medical care of mass casualties which are designed to cope with 50 to a maximum of 200 patients. Disaster simulations and practical exercises in Hannover regarding EXPO 2000 and the FIFA World Cup 2006 showed a very good and effective prehospital treatment and management up to a number of about 200 patients. Due to infrastructural settings a scenario with up to 1,000 (MANV IV) patients in the region of Hannover was beyond the capacity of existing concepts for the management of mass casualties, which comprised initial medical care at the on-site treatment area and subsequent transport to local or regional hospitals for definitive management. A new practicable and well trained model was necessary to improve the hospital admission and primary treatment capacity (Erstversorgungsklinik--EVK). In the case of MANV IV it was proposed that the tasks of on-site treatment area should be concentrated on triage and the stabilization of severely injured victims with immediate transport to special primary care hospitals. The main task of these hospitals was further stabilization of patients for inhospital care or further transport to other special facilities.

The main aim of the study was, after the initial trauma scenario, to provide the logistical and personal background for the fastest possible advanced life support and the further treatment of more than 60 severely injured patients at a city hospital with trauma centre level I experience. The timescale from the first alarm until the hospital was ready for action was approximately 60 min. To gain knowledge about the regional implementation of the whole logistic scenario in the case of MANV IV and to practice detailed questioning, a major casualty training was needed. This resulted in a large targeted disaster medical training with a realistic situation simulation on the 25.03.2006 including the Diakoniekrankenhaus Friederikenstift under the aspect of a special primary care hospital (EVK) working at full capacity.

The AWD arena in Hannover was the site of a simulated major casualty event resulting in 620 patients with various penetrating or blunt trauma injuries. Within 60 min of the first alarm call the admission and casualty treatment capacity at the Diakoniekrankenhaus Friederikenstift was increased up to approximately 60 patients including 30 ventilated patients. After initial inspection of 78 patients according to the ATLS criteria advanced life support was performed (airway management, volume resuscitation, basic diagnostic and surgical techniques) by flexible treatment teams (including physicians of all other faculties) in 3 treatment corridors within 135 min. Of the patients 69 were admitted to the wards and intensive care units, 5 were discharged after ambulant treatment and 3 patients were transferred to an eye and ENT hospital. Of the patients 10 had already been intubated on arrival, another 6 patients were intubated in the treatment corridors. Simulations of 4 urgent laparatomies, 2 trepanations, 1 artery seam, osteosynthesis of 3 perforating fractures was performed in the operating theatre. A total of 6 extremity fractures were immobilized by a fixateur externe, 7 chest tubes were placed and 43 surgical wound dressings were performed in the treatment corridors. There was no significant shortage of logistical or personal resources.

In a major disaster with more than 200 seriously injured patients the EVK model is a practicable and regional well tried solution that could increase the capacity of hospital admissions and advanced trauma life support, regardless of the type of casualty, season or weather conditions. It is possible to reduce the interval to advanced trauma life support, temporary fracture stabilization (damage control) and definitive surgical care by means of rapid and targeted utilization of resources and manpower. Physicians involved in the initial treatment play a key role and have to be highly trained (ATLS). The EVK model is variable and can easily be established and adapted to regional conditions at basic regional hospitals as well as at level I trauma centers.