Prehospital treatment of TBI: general principles
Prehospital treatment of TBI focuses on rapid rescue of entrapped patients (e.g. from car wrecks), on immobilization of the spinal column to prevent further injury, on rapid medical treatment to stabilize vital functions to prevent secondary brain injury, and on rapid transport to definite medical treatment. This requires a close cooperation between ambulance, police and fire brigade units.
The first step in prehospital management of a trauma victim is to establish a safe environment for rescuers and patients alike. Herein, police personnel play a key role for directing traffic away from the accident location, or to enforce safety in violent surroundings. Likewise, fire brigade play an important role not only to protect victims and rescuers from smoke and fire, but also in controlling electrical, chemical or mechanical hazards.
When safe approach to the patient is possible, ambulance personnel will assess the patient‘s consciousness, airway, breathing and circulation, and will immobilize the cervical spinal column as soon as feasible. First basic therapeutic steps include administration of oxygen to prevent hypoxia and establishing venous access to allow application of infusions and medications.
Often, the patient may not be freely accessible but may be entrapped in a motor vehicle or other confined space (e.g. building pit). Removal of the patient from the accident site to allow further treatment and transport is often not trivial: On the one hand extrication should be as quickly as possible and on the other hand it should be as gentle as possible to prevent further injury especially to the spinal column. Choice of the right extrication technique is hence crucial and may determine further course and outcome of the patient. Again, fire brigade personnel play a key role in patient salvage and extrication as they have the necessary equipment and skills to recover entrapped victims. Herein, close collaboration between ambulance and fire brigade personnel is necessary to chose the right technique, depending on the patient‘s condition and on whether there is an ongoing threat to the patient in the current position. In exceptional circumstances, when the patient is unstable but cannot be extricated immediately, advanced life support measures such as endotracheal intubation must be attempted under very challenging conditions while the patient is still entrapped.
As soon as the patient is extricated and freely accessible, ambulance personnel will reassess the patient‘s vital functions, commence therapeutic steps as indicated and rapidly prepare the patient for transport to a trauma center. A main focus of prehospital medical management of TBI patients is to prevent and treat factors known to aggravate secondary brain injury (see section on general TBI information), especially hypoxia and hypotension. The American Brain Trauma Foundation published detailed guidelines for pre- an in-hospital treatment of TBI, which can be downloaded here. These guidelines are internationally accepted and form the basis of treatment recommendations in the Netherlands. However, although much research has been published on TBI treatment, the scientific evidence underlying the recommendations is low. Hence, current guidelines reflect an expert consensus but optimal prehospital treatment is still basically unknown. More information and examples of this dilemma along with a description on how the BRAIN-PROTECT project will contribute in filling this gap of knowledge is described in the Research section.
Emergency Medical Services (EMS) in the Netherlands
For the purpose of emergency management, civil protection and disaster control, the Netherlands have been portioned in 25 regions, in which ambulance services, police, fire brigade and civil protection collaborate closely. Each region (except for one) operates an ambulance dispatch center, which responds to an emergency call and dispatches ambulances as well as other units as required. The Netherlands counts approximately one million ambulance missions each year, of which about two thirds are emergency missions while the rest are less urgent ambulance duties such as inter-hospital transfers. For high urgency emergency situations, the targeted response time until the ambulance reaches the patient is 15 minutes or less. This target has been reached in 92.3% in 2010. For some types of emergencies, the ground ambulance service is supplemented by a physician staffed helicopter ambulance (MMT, see below).
An ambulance in the Netherlands is staffed by a specially qualified driver and a specially qualified registered nurse. The ambulance driver has a background as professional driver and qualifies for ambulance service in a special training in which he acquires proficiency to drive with optic and acoustic signaling under emergency conditions. Moreover, the driver receives medical training which enables him to competently assist the ambulance nurse in patient treatment.
Ambulance nurses must successfully have absolved advanced training in a medical unit pertaining to emergency medicine such as an intensive care unit or emergency department. Subsequently, the nurse can qualify as ambulance nurse in a special national training program. Ambulance nurses in the Netherlands are allowed to administer a broad range of emergency drugs and to perform emergency interventions (including endotracheal intubation in patients with a GCS score of 3), as specified in national ambulance protocols.
A broad variety of information on EMS and ambulance services in the Netherlands can be found on the official website of the number one sector organization for ambulance care.
Mobile Medical Team (MMT)
To support ground ambulance staff, 4 ambulance helicopters called „Lifeliners“ are available in the Netherlands. Lifeliners provide 24-7 service and their primary aim is to transport a Mobile Medical Team (MMT) as quickly as possible to the accident location. Lifeliner helicopters are also capable of transporting patients to a trauma center, however this is only done infrequently because in the Netherlands ground ambulance transport is usually quicker due to short distances to one of the 11 trauma centers.
Lifeliner 1 is based in Amsterdam (VU University Medical Center), Lifeliner 2 in Rotterdam (Rotterdam Airport, medical staff from Erasmus Medical Center), Lifeliner 3 in Nijmegen (Volkel military airbase, medical staff from University Medical Center St. Radboud Nijmegen) and Lifeliner 4 is based in Groningen (University Medical Center Groningen).
A helicopter MMT basically consists of a pilot, flight nurse and an emergency physician. Lifeliner helicopters are operated by Medical Air Ambulance (MAA), who provide aircraft (currently type Eurocopter EC 135) and pilots. Pilots hold a commercial pilot license (CPL-H) or airline transport pilot license (ATPL-H) for helicopters. Since flying under ambulance conditions is more challenging than regular helicopter operations, e.g. due to time pressure, night operations and due to the necessity to land in difficult off airport terrain, MMT pilots are required to have a considerable experience and receive additional training to meet the demands of ambulance helicopter operations .
Flight nurses are either ambulance nurses or emergency department nurses with a special training as HEMS Crew Member (HCM, helicopter EMS crew member). The flight nurse assumes co-pilot duties in preparation for flight and during flight, for example by handling aviation checklists and by assisting the pilot in navigation and communication with air traffic control. At the accident location, the flight nurse is involved in patient treatment together with the emergency physician and ground ambulance personnel.
MMT-physicians are most often medical specialists in anesthesiology or surgery. In the Netherlands, both specialties require a training of five years, including training in trauma anesthesia and intensive care medicine (for anesthesiologists) or traumatology (for surgeons). Moreover, MMT physicians are trained in the peculiarities of the prehospital and helicopter work environment. Hence, all MMT emergency physicians have ample expertise in acute management of trauma patients.
In MMT-bases located on a hospital roof (Amsterdam and Groningen), a heli landing officer (HLO) assumes fire fighter duties to ensure safety during take-off and landing of the helicopter. The HLO is a specially trained ambulance driver, who also drives the MMT by car ambulance when the helicopter cannot fly (e.g. due to weather conditions or technical defects), or when the accident location is in close proximity to the hospital.
The MMT is either primarily dispatched by the dispatch center or can be secondarily requested by ambulance personnel. Primary dispatch criteria for trauma include severe trauma mechanism, trauma with reported unconsciousness or respiratory or hemodynamic instability, as well as traumatic resuscitations. An MMT helicopter basically carries the same equipment and medication as a ground ambulance, but offers a broader range of special instruments and medications.
The MMT physician is well trained to perform emergency interventions such as endotracheal intuabtion with the use of neuromuscular blocking agents, cricothyrotomies or placement of chest drains. Moreover, the MMT physician is not bound to ambulance treatment protocols but can commence treatments at his or her judgement as medical specialist, such as administration of hypertonic saline or mannitol for control of increased intracranial pressure. Hence, the role of the MMT is not to replace, but to supplement ground ambulance personnel by contributing special expertise in airway management, pharmacotherapy and surgical techniques.