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Physician staffed helicopter emergency medical systems can provide advanced trauma life support in mountainous and remote areas
Accepted Manuscript Title: Physician staffed helicopter emergency medical systems can provide advanced trauma life support in mountainous and remote areas Author: Ausserer Julia MD Moritz Elizabeth MD Stroehle Matthias MD Brugger Hermann MD Strapazzon Giacomo MD PhD Rauch Simon MD Mair Peter MD-group id="aug0010"> Bonsante Francesco Brandst¨atter Manfred Dal Cappello Tomas Druge ¨ Gerold Falk Markus Fop Ernst Frasnelli Andreas Gasteiger Lukas Gruber Elisabeth Hofer Georg Lunz Wolfgang Palma Martin Ploner Franz Rammlmair Georg Trincanato Alberto Turner Rachel Zanon Peter Voelckel Wolfgang Dengg Clemens Kettner Margareth PII: DOI: Reference:
S0020-1383(16)30435-1 http://dx.doi.org/doi:10.1016/j.injury.2016.09.005 JINJ 6891
To appear in:
Injury, Int. J. Care Injured
Received date: Revised date: Accepted date:
29-6-2016 17-8-2016 2-9-2016
Please cite this article as: Julia A, Elizabeth M, Matthias S, Hermann B, Giacomo S, Simon R, Peter M, Physician staffed helicopter emergency medical systems can provide advanced trauma life support in mountainous and remote areas, Injury (2016), http://dx.doi.org/10.1016/j.injury.2016.09.005 This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.
Physician staffed helicopter emergency medical systems can provide advanced trauma life support in mountainous and remote areas Authors: Ausserer Julia, MD a, Moritz Elizabeth, MD a, Stroehle Matthias, MD a, Brugger Hermann, MD b, Strapazzon Giacomo, MD PhD b, Rauch Simon, MD b, Mair Peter, MD a*; International Alpine Trauma Registry Study Group. a
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*Corresponding author: Peter Mair Department of Anaesthesiology and Critical Care Medicine Innsbruck Medical University Anichstrasse 35 6020 Innsbruck, Austria Email: [email protected] Tel: +43-512-504-80415
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Department of Anaesthesiology and Critical Care Medicine, Innsbruck Medical University, Anichstrasse 35, 6020 Innsbruck, Austria b EURAC Institute of Mountain Emergency Medicine, Drususallee 1, 39100 Bolzano, Italy
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International Alpine Trauma Registry Study Group: Bonsante Francesco1, Brandstätter Manfred2, Dal Cappello Tomas3, Drüge Gerold4, Falk Markus3, Fop Ernst2, Frasnelli Andreas5, Gasteiger Lukas1, Gruber Elisabeth6, Hofer Georg7, Lunz Wolfgang8, Palma Martin3, Ploner Franz9, Rammlmair Georg10, Trincanato Alberto3, Turner Rachel3, Zanon Peter1 , Voelckel Wolfgang11, Dengg Clemens12, Kettner Margareth13 1
Department of Intensive Care Medicine, Regional Hospital Bozen, Italy Emergency Dispatch Centre 118/115, Health Services of Bozen, Italy 3 EURAC Institute of Mountain Emergency Medicine, Bolzano, Italy 4 Department of Anesthesiology and Critical Care Medicine, General Hospital Meran, Italy 5 Regional Hospital, Visp, Switzerland 6 Department of Anesthesiology and Critical Care Medicine, General Hospital Bruneck, Italy 7 Department of Anesthesiology and Critical Care Medicine, General Hospital Schlanders, Italy 8 Department of Anaesthesiology and Critical Care Medicine, General Hospital Innichen, Italy 9 Department of Anaesthesiology and Critical Care Medicine, General Hospital Sterzing, Italy 10 Department of Anaesthesiology and Critical Care Medicine, General Hospital Brixen, Italy 11 Medical Director, Christophorus Air Rescue Service, Vienna, Austria 12 Department of Anaesthesiology and Critical Care Medicine, Regional Hospital Kufstein, Austria 13 Department of Anaesthesiology and Critical Care Medicine, Regional Hospital St. Johann, Austria
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Abstract Introduction In remote and mountainous areas, helicopter emergency medical systems (HEMS) are used to expedite evacuation and provide pre-hospital advanced trauma life support (ATLS) in major trauma victims. Aim of the study was to investigate feasibility of ATLS in HEMS mountain rescue missions and its influence on patient condition at hospital admission. Patients 58 major trauma victims (Injury Severity Score ≥16), evacuated by physician staffed HEMS from remote and mountainous areas in the State of Tyrol, Austria between 1.1.2011 and 31.12.2013. Results Pre-hospital time exceeded 90 minutes in 24 (44%) cases. 31 (53%) patients suffered critical impairment of at least one vital function (systolic blood pressure <90 mmHg, GCS <10, or respiratory rate <10 or >30). 4 (6.9%) of 58 patients died prior to hospital admission. Volume resuscitation was restrictive: 18 (72%) of 25 hypotensive patients received ≤500 ml fluids and blood pressure was increased >90 mmHg at hospital admission in only 9 (36%) of these 25 patients. 8 (50%) of 16 brain trauma patients with a blood pressure <90 mmHg remained hypotensive at hospital admission. Endotracheal intubation was accomplished without major complications in 15 (79%) of 19 patients with a Glasgow Coma Scale score <10. Rope operations were necessary in 40 (69%) of 58 cases and ATLS was started before hoist evacuation in 30 (75%) of them. Conclusions The frequent combination of prolonged pre-hospital times, with critical impairment of vital functions, supports the need for early ATLS in HEMS mountain rescue missions. Pre-hospital endotracheal intubation is possible with a high success and low complication rate also in a mountain rescue scenario. Pre-hospital volume resuscitation is restrictive and hypotension is reversed at hospital admission in only one third of patients. Prolonged pre-hospital hypotension remains an unresolved problem in half of all brain trauma Page 2 of 14
patients and indicates the difficulties to increase blood pressure to a desired level in a mountain rescue scenario. Despite technical considerations, on-site ATLS is feasible for an experienced emergency physician in the majority of rope rescue operations. (Word count: 330)
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Keywords Advanced trauma life support, Mountain rescue, Helicopter, Emergency physician, Trauma, Endotracheal intubation, Volume resuscitation.
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Introduction Major trauma occurring in remote and mountainous areas, specifically not accessible to equipped medical vehicles, are prime examples of a pre-hospital care scenario which will require the dispatch of a Helicopter Emergency Medical Service (HEMS) (1, 2, 3). Although data are limited, it is widely accepted that HEMS activation will dramatically reduce prehospital times and thereby mortality in this group of high risk patients (2). Furthermore, HEMS dispatch offers the possibility to provide advanced trauma life support (ATLS) at the scene of any incident, interventions which are not necessarily synonymous with rescue missions in mountainous and remote areas (2, 4). Currently the influence of ATLS at the scene on mortality of trauma victims remains controversial (5, 6). Nevertheless, early ALS treatment is increasingly used during HEMS mountain rescue missions (7, 8, 9), and included in consensus recommendations on the use of helicopters in mountain rescue published by the International Commission for Mountain Emergency Medicine (ICAR MEDCOM) (2, 4). To date, very little data have been published in peer reviewed literature investigating the feasibility of, and problems associated with ATLS interventions under difficult conditions of a mountain rescue mission. Equally, the influence of these interventions on patient condition on hospital admission has not been explored more in detail in remote and mountainous environments. Aim of the current study therefore was to investigate feasibility and consequences of ATLS interventions in HEMS mountain rescue missions in patients with major trauma. Patients and Methods Patients entered into the International Alpine Trauma Registry (IATR) (10) by the Innsbruck trauma centre from 1.1.2011 to 31.12.2013 were reviewed with the aim to identify victims sustaining major trauma during recreational activities in mountainous terrain. The IATR is a prospective, observational multi-centre study including patients sustaining major trauma in remote and mountainous areas not accessible to medical motor vehicles (10). Medical inclusion criteria for the IATR are an ISS ≥ 16; and/or systolic blood pressure < 90 mmHg; and/or respiratory rate < 10 or > 30, at the scene of the incident. Patients who suffered accidents on resort prepared ski slopes were excluded. The IATR has been approved by the Ethical Committee of Innsbruck Medical University and subjects gave informed consent to the study. Once inclusion criteria were met, patient data relating to accident characteristics and rescue mission considerations were retrieved from the registry; namely, type of activity and mechanism of injury, technical difficulty of terrain, terrestrial rescue, air rescue or combined rescue, and in case of air rescue necessity for rope operation. All related patient treatment data was reviewed, inclusive of: total pre-hospital time; Glasgow Coma Scale (GCS); systolic blood pressure and respiratory rate at the scene; incidence, type and timing of pre-hospital ATLS interventions; Glasgow Coma Scale (GCS); systolic blood pressure, respiratory rate and arterial oxygen saturation on hospital admission; Abbreviated Injury Scale (AIS) (11); Page 3 of 14
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Injury Severity Score (ISS) (11); pre-hospital and in-hospital mortality; body core temperature on admission; and necessity for immediate intervention (within 2 hours) post hospital admission. The Tyrolean Alps are served by a dense network of physician staffed emergency medical helicopters, 8 of which are operational in the summer season and up to 15 in the winter. HEMS teams are specifically positioned throughout Tyrol to ensure a comprehensive rescue service, with a response time of ≤ 15 minutes post activation, even in mountainous or remote locations. All helicopters are staffed with a pilot, a medically trained rescuer and an emergency physician. The medically trained rescuers have a standardised formal training in helicopter rope rescue operations and physician assistance, plus a varying experience in terrestrial mountain rescue techniques. All HEMS emergency physicians are certified by the Austrian Medical Association as standard and must be willing to take part in rope rescue operations. Additionally, they must complete annual formal training in helicopter rope rescue operations, maintain physical fitness and have some basic experience in moving in alpine terrain. Post HEMS activation the team flies directly to the scene of the accident to get an overview of the situation. On arrival, the crew must first decide whether the emergency physician and the rescuer can manage the situation alone, or whether they need further terrestrial support from the Tyrolean Mountain Rescue Service (TMRS). Median, interquartile range and range were calculated to describe continuous variables.
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Results During the 3 years study period a total of 65 patients, all of whom sustained major trauma during recreational activities in mountainous terrain, were included into the IATR by the Innsbruck trauma centre. Seven of these 65 patients (11%) were rescued and evacuated without helicopter support and therefore excluded from further analysis. The remaining 58 patients entered the study (47 men, plus 11 women; 49 ± 15 years ( mean age ± SD)). Accident and mission characteristics The majority of the accidents occurred in the summer season whilst hiking, mountaineering, rock climbing or paragliding (Table 1). Within 44 of 58 cases (76%), fall was by far the most common underlying mechanism for injury, whereas only one case of penetrating trauma was observed (2%). Of the 58 patients, only 16 patients (28%) were evacuated from ‘easy terrain’, where specific mountaineering skills were not required for successful evacuation. Whereas, thirty-six (62%) had to be extricated from ‘difficult terrain’, where basic mountaineering experience to access the victim was required; and in 6 cases (10%), belaying of the rescuers was necessary for the evacuation. In 40 patients (69%), evacuation from the scene was possible only with help of a rope rescue operation (winch or hoist operation). Forty-seven patients (81%) were rescued solely by the HEMS crew (pilot, rescuer and emergency physician). However, in the remaining 11 patients (19%) additional terrestrial support from the TMRS was necessary, either due to adverse weather conditions or terrain difficulty obstructing direct helicopter access to the rescue site. Median pre-hospital time (time from accident to hospital admission) was 80 ± 44 minutes (median ± interquartile range; range from 28 minutes to 17 hours). In 10 patients (18%) prehospital time exceeded 120 minutes either due to delayed HEMS activation (5 patients), or prolonged access time and/or time consuming evacuation process (5 patients) (Table 2). Injury pattern Median ISS of the 58 patients reviewed was 34 ± 18 (median ± interquartile range; range 2075). Life threatening injuries (AIS Score ≥ 4), were found predominantly in the head/neck and chest regions (Table 3). ATLS Interventions at scene
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ATLS interventions at scene were performed in 57 of the 58 (98%) patients reviewed (Table 4). Only one patient had a crash evacuation to hospital solely with basic life support (BLS) interventions. An intravenous line was inserted in 57 of the 58 patients (98%). In 48 patients (83%) volume resuscitation was started at scene, with 26 patients (45%) receiving up to 500 ml volume and only 10 patients (17%) receiving more than 1000 ml volume prior to hospital admission. More than half of all patients received intravenous analgesic drugs (opioids or ketamine or a combination of both). Twenty-one patients (36%) had an endotracheal tube inserted at the scene, in 17 of those (81%) endotracheal intubation was facilitated with muscle relaxant. In one further patient repeated attempts at endotracheal intubation failed, eventually the airway of the patient was successfully managed with a laryngeal tube. No major complications of endotracheal intubation were reported. Post hospital admission, two endotracheal tubes had to be retracted from the right main bronchus, with concomitant left sided lung atelectasis evident in CT scan in both patients. In 3 patients, admission CT scan showed marked distension of the upper gastrointestinal tract due to air inflation; thus indicating problems with bag mask ventilation or endotracheal intubation at scene. ATLS interventions in patients with critically impaired vital functions Twenty-seven of the 58 patients (47%) had no critical impairment of vital functions (systolic blood pressure ≥ 90 mmHg, GCS ≥ 10 and respiratory rate between 10 - 30 BPM); as assessed by the rescue team on arrival at scene. The remaining 31 patients (53%) had at least one vital function critically impaired. In 25 of the 58 patients (43%) systolic pressure was < 90 mmHg or unobtainable, 19 patients (33%) had a GCS < 10 and 2 patients (3%) had a respiratory rate < 10 BPM. Nine of the 25 patients (36%) with an initial systolic pressure < 90 mmHg at scene, had their systolic blood pressure increase ≥ 90 mmHg on arrival to the emergency room; in 13 patients (52%) systolic blood pressure remained < 90 mmHg; whereas, three (12%) sustained cardiorespiratory arrest prior to hospital admission and subsequently died. Only 7 of all 25 patients (28%) received volume resuscitation exceeding 500 ml prior to hospital admission. Sixteen of these 25 patients (64%) had concomitantly suffered traumatic brain injury, which was verified in all cases by CT scan. In 8 of these 16 patients (50%), systolic blood pressure was increased to ≥ 90 mmHg at hospital admission. In 3 further cases with a systolic blood pressure ≥90 mmHg at rescue team arrival, blood pressure subsequently fall < 90 mmHg prior to hospital admission. One of these 3 patients sustained cardio-respiratory arrest and died at scene. Seventeen of the 19 patients (89%) with an initial GCS ≤ 9 received advanced airway management at the scene (endotracheal intubation n = 15, laryngeal tube n = 2). Whereas, two patients had a ‘crash evacuation’ (rope rescue), directly to a hospital helipad less than 5 minutes flight time away. Both with BLS airway management. Those 2 patients whom on first examination had a respiratory rate below 10 BPM, also had a GCS < 10 and both received endotracheal intubation at the scene. All patients breathing spontaneously at hospital admission had a respiratory rate between 10 - 30 BPM, plus documented oxygen saturations above 85% on hospital admission. ATLS interventions in rope rescue operations In total, 10 of the 40 patients (25%) rescued with rope rescue techniques received only BLS interventions prior to evacuation out of difficult terrain. Whereas, the remaining 30 patients (75%) all received ATLS interventions directly prior to rope evacuation. All (75%) had an intravenous line inserted, 23 patients (58%) received analgesic drugs and/or volume resuscitation, and 5 patients (13%) had an endotracheal intubation (corresponding to 50% of all endotracheal intubations eventually performed in these 40 patients prior to hospital admission). In-hospital interventions and mortality
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Immediate life-saving interventions post hospital admission (within 2h), were necessary in 14 patients (24%). Interventions included: tube thoracostomy (n = 4), emergency surgery for bleeding control (n = 3), emergency intracranial surgery (n = 4), emergency radiological intervention for bleeding control (n = 3) and implantation of an extracorporeal life support system (n = 1). Overall, four patients (7%) presented with a body core temperature ≤ 28°C on admission. Out-of-hospital mortality was recorded as 6.9% (n = 4). Whereas, in-hospital mortality equalled 10.3% (n = 6), of which 5 patients died within 12 hours of admission. Cause of early in-hospital death was irreversible neurological injury in 4 patients, 1 patient died from uncontrolled bleeding. The sixth patient died from septic multi-organ failure after a prolonged ICU stay.
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Discussion Available data concerning the pattern of injury in major trauma victims involved in mountain rescue missions are limited. Previous publications analysing mountain rescue missions included only few cases of major trauma as in the majority of mountain rescue missions, severity of injury is low with a concomitant high rate of non-life-threatening limb injuries (12, 13). This is also true for HEMS mountain rescue missions (3, 14, 15). Even in accidents involving major falls in Alpine terrain, incidence of critical trauma with an ISS > 20 is estimated at only 17.5% (16). In a necropsy study of fatal trauma after mountaineering accidents Reid et al., found a rate of traumatic brain injury of over 50% (17). Brain trauma was also the leading cause of death in this study, whereas exsanguination was uncommon (17). In contrast, Hohlrieder et al. found a low rate of severe brain trauma, but a high rate of pelvic fractures, spine fractures and major thoracic injuries in victims of major Alpine falls (16). In a study analysing casualties rescued by the Scottish Mountain Rescue Service Hearns reported a 33% early mortality rate among 12 major trauma victims, due to the severity of the underlying trauma and hypothermia (18). In review, the 58 alpine major trauma victims included in this study depicted a similar trend. Early mortality (pre-hospital or within 12 h post hospital admission) was at 15.5% and was caused by brain trauma and occasional cases of exsanguination. Major life-threatening injuries were found predominantly in the head /neck and chest region. Severe hypothermia, with a core temperature ≤28°C was present in 7% of all patients. In summary, severe brain and chest trauma as well as concomitant accidental hypothermia are common in major trauma victims involved in mountain rescue missions significantly contributing to early mortality. It is widely believed that early admission to a trauma centre within the golden hour of shock is associated with a reduced mortality and 90 minutes is the upper acceptable limit for total prehospital time recommended in the guidelines released by the German Society for Trauma Surgery (19). In this study population, despite helicopter support, total pre-hospital time exceeded 90 minutes in 44% of all mountain rescue missions. In the majority of cases, prolonged pre-hospital time was due to the necessity for rope rescue manoeuvres whilst accessing and evacuating the patient. Further delays in patient retrieval were encountered when additional terrestrial support was required to extract the patient successfully, total prehospital time often exceeding 2 hours. Despite the use of helicopters, due to the difficult terrain and adverse weather conditions often encountered in these rescue missions, prehospital times remain prolonged in many HEMS mountain rescue missions. Prolonged prehospital time is an important factor when debating the early employment of ATLS by an emergency physician at the scene (20, 21). In these remote or mountainous environments a ‘scoop and run’ concept is not an option in the majority of cases, therefore the availability of HEMS provided ATLS in major trauma victims in mountain terrain is considered potentially beneficial (20, 21).
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In the event of traumatic brain injury, the importance of protecting the airway and avoiding hypoxia and hypercapnia in affected patients, is a major proponent for early ATLS at scene (20, 22, 23). However, to date outcome data are conflicting and the actual influence of prehospital advanced airway management on morbidity and mortality of traumatic brain injury remains controversial (23, 24). In 1993 Malacrida and co-workers reported a low morbidity and mortality rate for head injury patients after mountaineering accidents when rescued by a physician staffed helicopter (9). In this case, the authors concluded that ATLS provided by an emergency physician is an effective way to reduce secondary cerebral damage in brain trauma victims in remote mountain terrain (9). Likewise, 79% of major trauma patients in this study population with a Glasgow Come Score ≤9 had their airways supported by prehospital endotracheal intubation. Traumatic brain injury with a GCS score ≤9 is considered an indication for endotracheal intubation at the scene in many emergency medical systems (EMS) (9, 19, 22, 23). In European physician staffed EMS, endotracheal intubation is currently considered the gold standard for advanced pre-hospital airway management (25, 26, 27). Correspondingly, high success and low complication rates have been repeatedly reported for pre-hospital endotracheal intubation by experienced physicians (26, 27). Equally, results of this study demonstrated that for experienced emergency physicians, pre-hospital endotracheal intubation is associated with a 90% success rate and a low rate of minor complications despite the difficulties associated with ATLS in a mountain rescue mission. More than two thirds of all endotracheal intubations in this study population were muscle relaxant facilitated. Beside extensive training and regular experience in the procedure, the use of muscle relaxants is another known factor facilitating pre-hospital endotracheal intubation (20, 23, 25). Our data demonstrated a restrictive approach in volume resuscitation in HEMS mountain rescue missions as pre-hospital volume resuscitation was below 500 ml in almost half of patients and exceeded 1000 ml in only 17%. Recent publications investigating resuscitation strategies for traumatic shock in European EMS also document low volumes of fluids being administered during pre-hospital resuscitation of trauma victims (28, 29). Currently, restrictive volume resuscitation is a widely accepted approach in normotensive multi-system trauma victims, however it is still controversial in hypotensive patients with a systolic blood pressure below 90 mmHg (30, 31). Nevertheless, within this review, 72% of patients who were reportedly hypotensive at the scene also had low volume fluid resuscitation up to 500 ml. Furthermore, a quarter of all study patients had a blood pressure below 90 mmHg on hospital admission. Both suggest a preference for a “deliberate hypotension concept” for fluid resuscitation during HEMS mountain rescue missions. The concept of “deliberate hypotension” is particularly popular in military medicine (32), but has also been recommended as therapeutic approach of choice for situations with delayed evacuation like mountain rescue missions (33). However, it is likely that low volume resuscitation was not intentional in all patients, but in some of them reflected the inability to infuse sufficient amounts of fluids in a hostile environment or during rope rescue manoeuvres. Hypertonic saline is an option to achieve blood volume expansion with lower amounts of resuscitation solution (34, 35). Therefore it may be a reasonable choice in HEMS mountain rescue missions as reduced weight and infusion volume are obviously decisive factors for the choice of resuscitation solution. The benefits of small volume resuscitation with hypertonic solutions alone or combined with dextran have been outlined for military medicine (32), but have been questioned for civilian trauma victims (34, 35). Due consideration is necessary as there is evidence that the concept of deliberate hypotension may be harmful in patients with concomitant brain trauma (22, 23, 33). Systolic blood pressure in our study population was increased to values exceeding 90 mmHg in only half of all hypotensive patients with concomitant traumatic brain injury. This shows that the treatment of prolonged pre-hospital hypotension remains an unresolved problem and indicates Page 7 of 14
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the difficulties of increasing pressure to a desired level in many cases of brain injury in a mountain rescue scenario. Although evidence to support the use of vasopressors in the treatment of haemorrhagic shock is limited, the administration of vasopressors to reverse lifethreatening hypotension has been suggested for mountain emergency medicine (33). Rope rescue operations were necessary to access and evacuate the victim in more than two thirds of all missions reviewed. Therefore, providing ATLS at the scene in HEMS mountain rescue mission will regularly necessitate involving emergency physicians in rope rescue operations. The proficiency of emergency physician in winch and hoist operations has already been highlighted mostly as a consideration in analgesic drug administration at the scene for non-life-threatening, painful injuries (3, 14, 36). Equally, the effectiveness of intravenous analgesia in mountain rescue missions has been recently demonstrated by Ellerton et al. (37). Intravenous analgesic drug administration was also necessary in more than half of the major trauma patients reviewed in this study. Sufficient patient pain relief may be crucial to ensure a rapid rescue and evacuation from technically demanding terrain, and is thus an important contribution of an emergency physician to the success and safety of the mission. Previous publications (3, 14, 36) included only occasional cases of severe trauma and therefore reported low rates of major medical interventions in rope rescue operations. Our data indicate that in case of severe trauma in HEMS mountain rescue missions, major medical interventions like endotracheal intubation are necessary and feasible on a regular basis; both in roped or non-roped rescue operations. Providing ATLS support during HEMS mountain rescue missions requires some basic alpine skills and a reasonable physical fitness of the emergency physicians involved. In Tyrol, no formal minimal requirement for alpine skill set or physical fitness exist for operational emergency physicians involved in HEMS mountain rescue missions. In fact, qualifications vary over a wide range, from rather basic alpine training to mountain guide level. Previous publications analysing wilderness and mountain rescue missions reported that ~60% of all missions require only basic technical skills as the rescue teams operated solely within a terrain of moderate grade of difficulty (12, 38). Comparable to our data, these publications also report that a small number of missions occur in extreme terrain and need belaying of the rescue team (38). To also cover these uncommon scenarios, Kueppers et al. recommend that rescue personnel involved in HEMS mountain rescue missions should be competent in rock climbing up to a difficulty of UIAA scale grade IV (38). However, in most cases of major trauma a rapid evacuation to a less exposed terrain using basic trauma life support interventions is a reasonable, if not the preferable, alternative. ICAR MEDCOM recommendations do not stipulate the need for advanced climbing and mountaineering skills in HEMS physicians involved in mountain rescue missions. The recommendations rather point out the importance of basic technical skills and physical fitness, combined with distinct qualities; such as, “being able to work under extreme conditions”, “must be comfortable in exposed situations” or “must be conscious of own safety” (4). Conclusions In review, the frequent combination of prolonged pre-hospital times, with critical impairment of vital functions, supports the need for early prehospital ATLS by an emergency physician in HEMS rescue operations in mountainous and remote areas. Pre-hospital airway protection with endotracheal intubation is possible with a high success and low complication rate, and can be accomplished in the majority of patients with severe brain trauma. Prolonged prehospital hypotension remains an unresolved problem in half of all patients with brain injury and indicates the difficulties to increase pressure to a desired level in a mountain rescue scenario. Pre-hospital volume resuscitation of hypotensive patients is restrictive and hypotension is reversed at hospital admission in only one third of patients. Despite technical considerations, for an experienced emergency physician ATLS is also feasible in the majority of rope rescue operations.
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Acknowledgement We thank Ms Rachel Turner for her support in revising the manuscript.
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References 1. Floccare D, Stuhlmiller D, Braithwaite S, Thomas S, Madden J, Hankins D, et al. Appropiate and safe utilization of helicopter emergency medical services: a joint postion statement with resource document. Prehospital Emergency Care 2013; 59:521-5. 2. Tomazin I, Kovacs T. Medical Considerations in the use of helicopters in mountain rescue. High Alt Med Biol 2003; 4:479-83. 3. Pasquier M, Geiser V, De Riedmatten M, Carron PN. Helicopter rescue operations involving winching of an emergency physician. Injury 2012; 43:1377-80. 4) 4. Tomazin I, Ellerton J, Reisten O, Soteras I, Avbelj M. Medical standards for mountain rescue operations using helicopters: official consensus recommendations of the International Commission for Mountain Emergency Medicine (ICAR MEDCOM). High Alt Med Biol 2011; 12:335-41. 5. Bakalos G, Mamali M, Komninos C, Koukou E, Tsantilas A, Tzima S, et al. Advanced life support versus basic life support in the pre-hospital setting: a meta-analysis. Resuscitation 2011; 82: 1130-7. 6. Ryynanen OP, Iirola T, Reitala J, Palve H, Malmivaara A. Is advanced life support better than basic life support in prehospital care? A systematic review. Scand J Trauma Resusc Emerg Med 2010; 18:62-76. 7. Brugger H, Elsensohn F, Syme D, Sumann G, Falk M. A survey of emergency medical services in mountain areas of Europe and North America. High Alt Med Biol 2005; 6:226-237. 8. Mair P, Frimmel C, Vergeiner G, Hohlrieder M, Moroder L, Hoesl P, Voelckel W. Emergency medical helicopters operations for avalanche accidents. Resuscitation 2013; 84: 492-5. 9. Malacrida R, Anselmi L, Genoni M, Bogen M, Suter P. Helicopter mountain rescue of patients with head injury and/or multiple injuries in southern Switzerland 1980-1990. Injury 1993; 24:451-3. 10. Strapazzon G, Costanzi E, Bonsante E, Rilk C, Mair P, Brugger H. International Alpine Trauma Registry: preliminary results for trauma life support in the mountains. Resuscitation 2013; 84 (Suppl):S S8–9.
11. Camp LV and Yates DW. Trauma Scoring. In Soreide E and Grande CM, editors. Prehospital Trauma Care. 1st ed. New York: Marcel Dekker; 1993, p. 153-168. 12. Soteras I, Subirats E, Strapazzon G. Epidemiological and medical aspects of canyoning rescue operations. Injury 2015; 46:585-9. 13. Mort A, Godden D. UK mountain rescue casualties: 2002-2006. Emerg Med J 2010; 27:309-12. 14. Moeschler O, Refondini S, Hofliger C, Freeman J. Difficult aeromedical rescue situations: experience of Swiss pre-alpine helicopter base. J Trauma 1992; 33: 754-9. 15. Kaufmann M, Moser B, Lederer W. Changes in injury pattern and severity in a helicopter air-rescue system over a 6-year period. Wilderness Environ Med 2005; 17:44-50. 16. Hohlrieder M, Eschertzhuber S, Schubert H, Zinnecker R, Mair P. Severity and pattern of injury in alpine fall accidents. High Alt Med Biol 2004; 5:349-54. 17. Reid W, Doyle D. Necropsy study of mountaineering accidents in Scotland. J Clin Pathol 1986; 39:1217-20. 18. Hearns S. The Scottish mountain rescue casualty study. Emerg Med J 2003; 20:281-4. 19. Neugebauer E, Waydhas C, Lendermans S, Rixen D, Eikermann M, Pohlemann T. Clinical practice guidelines: the treatment of patients with severe and multiple traumatic injuries. Dtsch Arztebl Int 2012; 109:102-8.
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20. Lippert F and Soreide E. The role of the physician in prehospital trauma care. In Soreide E and Grande CM, editors. Prehospital Trauma Care. 1st ed. New York: Marcel Dekker; 2001, p. 153-68. 21. Smith MR, Alasdair KT. Prehospital care – scoop and run or stay and play? Injury 2009; 40 (Suppl 4): S23-6. 22. Hoogmartens O, Haselmans A, Van de Velde S, Crasten M, Sjölin H, Sabbe M, Aertgeerts B, Ramaekers D. Evidence-based prehospital management of severe traumatic brain injury. a comparative analysis of current clinical practice guidelines. Prehosp Emerg Care 2014; 18:265-73. 23. Hammell CL, Henning JD. Prehospital management of severe traumatic brain injury. BMJ 2009; 338:b1683. 24. Elm E, Schoettker P, Henzi I, Osterwalder J, Walder B. Pre-hospital tracheal intubation in patients with traumatic brain injury: systematic review of current evidence. Br J Anaesth 2009; 103:371-86. 25. Berlac B, Hyldmo P, Kongstad P, Kurola J, Nakstad A, Sandberg M, Scandinavian Society for Anaesthesiology and Intensive Care Medicine. Pre-hospital airway management: guidelines from a task force from the Scandinavian Society for Anaesthesiology and Intensive Care Medicine. Acta Anaesthesiol Scand 2008; 52:897-907. 26. Sunde GA, Heltne JK, Lockey D, B urns B, Sandberg M, Fredriksen K, et al. Airway management by physician staffed helicopter emergency medical services – a prospective, multicentre, observational study of 2,327 patients. Scand J Trauma Resusc Emerg Med 2015; 23:57-67. 27. Thoeni N, Piegeler T, Brueesch M, Sulser S, Haas T, Mueller SM, Seifert B, Spahn D, Ruetzler K. Incidence of difficult airway situations during prehospital airway management by emergency physicians – a retrospective analysis of 692 consecutive patients. Resuscitation 2015; 90:42-5. 28. Driessen A, Froehlich M, Schaefer N, Mutschler M, Defosse J, Brockamp T, et al. Prehospital volume resuscitation – did evidence defeat the crystalloid dogma? An analysis of the TraumaRegister DGU 2002-2012. Scand J Trauma Resusc Emerg Med 2016; 24:42-50. 29. Hampton D, Fabricant L, Differding J, Diggs B, Underwood S, La Cruz D, Holcomb J. Pre-hospital intravenous fluid is associated with increased survival in trauma patients. J Trauma Acute Care Surg 2013; 75:S9-S15. 30. Geeraedts L, Pothof L, Caldwell E, Klerk E, Amours S. Prehospital fluid resuscitation in hypotensive trauma patients: Do we need a tailored approach? Injury 2015; 46:4-9. 31. Brown J, Cohen M, Minei J, Maier R, West M, Billiar T, et al. Goal directed resuscitation in the prehospital setting: a propensity adjusted analysis. J Trauma Acute Care Surg 2013; 74:1207-14. 32. Butler F. Fluid resuscitation in tactical combat casualty care: brief history and current status. J Trauma 2011; 70 (Suppl 5):S11-S12. 33. Sumann G, Paal P, Mair P, Ellerton J, Dahlberg T, Zen-Ruffinen G, Zafren K, Brugger H. Fluid management in traumatic shock: a practical approach for mountain rescue. High Alt Med Biol 2009; 10:71-5. 34. Bulger E, May S, Kerby J, Emerson S, Stiell I, Schreiber M, et al. Out-of-hospital hypertonic resuscitation after traumatic hypovolemic shock: a randomized, placebo controlled trial. Ann Surg 2011; 253:431-41. 35. Bulger E, May S, Brasel K, Schreiber M, Kerby J, Tisherman S, et. Out-of-hospital resuscitation following severe traumatic brain injury: a randomized controlled trial. JAMA 2010; 304:1455-64. 36. Sherren PB, Hayes-Bradley C, Reid C, Burns B, Habig K. Are physicians required during winch rescue missions in an Australian helicopter emergency medical service. Emerg Med J 2014; 31:229-32.
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Table 1: Recreational activities (n = 58) Activity Hiking, mountaineering Rock climbing Off-piste and Backcountry skiing/boarding Paragliding Mountain biking
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number of patients n = 19 (33 %) n = 17 (29 %) n = 13 (22.5%) n = 7 (12 %) n = 2 (3.5 %)
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37. Ellerton JA, Greene M, Paal P. The use of analgesia in mountain rescue casualties with moderate or severe pain. Emerg Med J 2013; 30: 501-5. 38. Kuepper T, Hillebrandt D, Steffgen J, Schoeffl V. Safety in alpine helicopter rescue operations– minimal requirements of alpine skills for rescue personnel. Ann Occup Hyg 2013; 57:1180-8.
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Table 2: Total pre-hospital time (n = 54) Total pre-hospital time number of patients n = 29 (54%) ≤ 90 minutes 91-120 minutes n = 14 (26%) > 120 minutes n = 10 (18 %) unknown* n = 1 (2%)
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* time of accident unknown as accident was not witnessed
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Table 3: Distribution of 72 life-threatening injuries (AIS ≥ 4) over body regions in 54 patients admitted to hospital alive body region Number of injuries ≥ AIS 4 (%) Head/ neck n = 25 (35%) face n = 3 (4%) chest n = 27 (37%) abdomen n = 5 (7%) extremities n = 12 (17%) external none
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Table 4: ATLS interventions at scene (n = 58 patients) intervention patients (%) iv line n = 57 (98 %) volume resuscitation n = 48 (83 %) volume resuscitation ≤ 500 ml volume resuscitation 500 -1000 ml volume resuscitation > 1000 ml
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iv analgesic drugs n = 31 (53 %) endotracheal intubation n = 21 (36 %) laryngeal tube/mask n = 2 (3 %) tube thoracostomy n = 2 (3%) Abbreviations: ATLS = Advanced trauma life support, iv = intravenous.
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n = 26 (45%) n = 12 (21%) n = 10 (17%)
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S0020-1383(16)30435-1 http://dx.doi.org/doi:10.1016/j.injury.2016.09.005 JINJ 6891
To appear in:
Injury, Int. J. Care Injured
Received date: Revised date: Accepted date:
29-6-2016 17-8-2016 2-9-2016
Please cite this article as: Julia A, Elizabeth M, Matthias S, Hermann B, Giacomo S, Simon R, Peter M, Physician staffed helicopter emergency medical systems can provide advanced trauma life support in mountainous and remote areas, Injury (2016), http://dx.doi.org/10.1016/j.injury.2016.09.005 This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.
Physician staffed helicopter emergency medical systems can provide advanced trauma life support in mountainous and remote areas Authors: Ausserer Julia, MD a, Moritz Elizabeth, MD a, Stroehle Matthias, MD a, Brugger Hermann, MD b, Strapazzon Giacomo, MD PhD b, Rauch Simon, MD b, Mair Peter, MD a*; International Alpine Trauma Registry Study Group. a
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*Corresponding author: Peter Mair Department of Anaesthesiology and Critical Care Medicine Innsbruck Medical University Anichstrasse 35 6020 Innsbruck, Austria Email: [email protected] Tel: +43-512-504-80415
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Department of Anaesthesiology and Critical Care Medicine, Innsbruck Medical University, Anichstrasse 35, 6020 Innsbruck, Austria b EURAC Institute of Mountain Emergency Medicine, Drususallee 1, 39100 Bolzano, Italy
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International Alpine Trauma Registry Study Group: Bonsante Francesco1, Brandstätter Manfred2, Dal Cappello Tomas3, Drüge Gerold4, Falk Markus3, Fop Ernst2, Frasnelli Andreas5, Gasteiger Lukas1, Gruber Elisabeth6, Hofer Georg7, Lunz Wolfgang8, Palma Martin3, Ploner Franz9, Rammlmair Georg10, Trincanato Alberto3, Turner Rachel3, Zanon Peter1 , Voelckel Wolfgang11, Dengg Clemens12, Kettner Margareth13 1
Department of Intensive Care Medicine, Regional Hospital Bozen, Italy Emergency Dispatch Centre 118/115, Health Services of Bozen, Italy 3 EURAC Institute of Mountain Emergency Medicine, Bolzano, Italy 4 Department of Anesthesiology and Critical Care Medicine, General Hospital Meran, Italy 5 Regional Hospital, Visp, Switzerland 6 Department of Anesthesiology and Critical Care Medicine, General Hospital Bruneck, Italy 7 Department of Anesthesiology and Critical Care Medicine, General Hospital Schlanders, Italy 8 Department of Anaesthesiology and Critical Care Medicine, General Hospital Innichen, Italy 9 Department of Anaesthesiology and Critical Care Medicine, General Hospital Sterzing, Italy 10 Department of Anaesthesiology and Critical Care Medicine, General Hospital Brixen, Italy 11 Medical Director, Christophorus Air Rescue Service, Vienna, Austria 12 Department of Anaesthesiology and Critical Care Medicine, Regional Hospital Kufstein, Austria 13 Department of Anaesthesiology and Critical Care Medicine, Regional Hospital St. Johann, Austria
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Abstract Introduction In remote and mountainous areas, helicopter emergency medical systems (HEMS) are used to expedite evacuation and provide pre-hospital advanced trauma life support (ATLS) in major trauma victims. Aim of the study was to investigate feasibility of ATLS in HEMS mountain rescue missions and its influence on patient condition at hospital admission. Patients 58 major trauma victims (Injury Severity Score ≥16), evacuated by physician staffed HEMS from remote and mountainous areas in the State of Tyrol, Austria between 1.1.2011 and 31.12.2013. Results Pre-hospital time exceeded 90 minutes in 24 (44%) cases. 31 (53%) patients suffered critical impairment of at least one vital function (systolic blood pressure <90 mmHg, GCS <10, or respiratory rate <10 or >30). 4 (6.9%) of 58 patients died prior to hospital admission. Volume resuscitation was restrictive: 18 (72%) of 25 hypotensive patients received ≤500 ml fluids and blood pressure was increased >90 mmHg at hospital admission in only 9 (36%) of these 25 patients. 8 (50%) of 16 brain trauma patients with a blood pressure <90 mmHg remained hypotensive at hospital admission. Endotracheal intubation was accomplished without major complications in 15 (79%) of 19 patients with a Glasgow Coma Scale score <10. Rope operations were necessary in 40 (69%) of 58 cases and ATLS was started before hoist evacuation in 30 (75%) of them. Conclusions The frequent combination of prolonged pre-hospital times, with critical impairment of vital functions, supports the need for early ATLS in HEMS mountain rescue missions. Pre-hospital endotracheal intubation is possible with a high success and low complication rate also in a mountain rescue scenario. Pre-hospital volume resuscitation is restrictive and hypotension is reversed at hospital admission in only one third of patients. Prolonged pre-hospital hypotension remains an unresolved problem in half of all brain trauma Page 2 of 14
patients and indicates the difficulties to increase blood pressure to a desired level in a mountain rescue scenario. Despite technical considerations, on-site ATLS is feasible for an experienced emergency physician in the majority of rope rescue operations. (Word count: 330)
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Keywords Advanced trauma life support, Mountain rescue, Helicopter, Emergency physician, Trauma, Endotracheal intubation, Volume resuscitation.
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Introduction Major trauma occurring in remote and mountainous areas, specifically not accessible to equipped medical vehicles, are prime examples of a pre-hospital care scenario which will require the dispatch of a Helicopter Emergency Medical Service (HEMS) (1, 2, 3). Although data are limited, it is widely accepted that HEMS activation will dramatically reduce prehospital times and thereby mortality in this group of high risk patients (2). Furthermore, HEMS dispatch offers the possibility to provide advanced trauma life support (ATLS) at the scene of any incident, interventions which are not necessarily synonymous with rescue missions in mountainous and remote areas (2, 4). Currently the influence of ATLS at the scene on mortality of trauma victims remains controversial (5, 6). Nevertheless, early ALS treatment is increasingly used during HEMS mountain rescue missions (7, 8, 9), and included in consensus recommendations on the use of helicopters in mountain rescue published by the International Commission for Mountain Emergency Medicine (ICAR MEDCOM) (2, 4). To date, very little data have been published in peer reviewed literature investigating the feasibility of, and problems associated with ATLS interventions under difficult conditions of a mountain rescue mission. Equally, the influence of these interventions on patient condition on hospital admission has not been explored more in detail in remote and mountainous environments. Aim of the current study therefore was to investigate feasibility and consequences of ATLS interventions in HEMS mountain rescue missions in patients with major trauma. Patients and Methods Patients entered into the International Alpine Trauma Registry (IATR) (10) by the Innsbruck trauma centre from 1.1.2011 to 31.12.2013 were reviewed with the aim to identify victims sustaining major trauma during recreational activities in mountainous terrain. The IATR is a prospective, observational multi-centre study including patients sustaining major trauma in remote and mountainous areas not accessible to medical motor vehicles (10). Medical inclusion criteria for the IATR are an ISS ≥ 16; and/or systolic blood pressure < 90 mmHg; and/or respiratory rate < 10 or > 30, at the scene of the incident. Patients who suffered accidents on resort prepared ski slopes were excluded. The IATR has been approved by the Ethical Committee of Innsbruck Medical University and subjects gave informed consent to the study. Once inclusion criteria were met, patient data relating to accident characteristics and rescue mission considerations were retrieved from the registry; namely, type of activity and mechanism of injury, technical difficulty of terrain, terrestrial rescue, air rescue or combined rescue, and in case of air rescue necessity for rope operation. All related patient treatment data was reviewed, inclusive of: total pre-hospital time; Glasgow Coma Scale (GCS); systolic blood pressure and respiratory rate at the scene; incidence, type and timing of pre-hospital ATLS interventions; Glasgow Coma Scale (GCS); systolic blood pressure, respiratory rate and arterial oxygen saturation on hospital admission; Abbreviated Injury Scale (AIS) (11); Page 3 of 14
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Injury Severity Score (ISS) (11); pre-hospital and in-hospital mortality; body core temperature on admission; and necessity for immediate intervention (within 2 hours) post hospital admission. The Tyrolean Alps are served by a dense network of physician staffed emergency medical helicopters, 8 of which are operational in the summer season and up to 15 in the winter. HEMS teams are specifically positioned throughout Tyrol to ensure a comprehensive rescue service, with a response time of ≤ 15 minutes post activation, even in mountainous or remote locations. All helicopters are staffed with a pilot, a medically trained rescuer and an emergency physician. The medically trained rescuers have a standardised formal training in helicopter rope rescue operations and physician assistance, plus a varying experience in terrestrial mountain rescue techniques. All HEMS emergency physicians are certified by the Austrian Medical Association as standard and must be willing to take part in rope rescue operations. Additionally, they must complete annual formal training in helicopter rope rescue operations, maintain physical fitness and have some basic experience in moving in alpine terrain. Post HEMS activation the team flies directly to the scene of the accident to get an overview of the situation. On arrival, the crew must first decide whether the emergency physician and the rescuer can manage the situation alone, or whether they need further terrestrial support from the Tyrolean Mountain Rescue Service (TMRS). Median, interquartile range and range were calculated to describe continuous variables.
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Results During the 3 years study period a total of 65 patients, all of whom sustained major trauma during recreational activities in mountainous terrain, were included into the IATR by the Innsbruck trauma centre. Seven of these 65 patients (11%) were rescued and evacuated without helicopter support and therefore excluded from further analysis. The remaining 58 patients entered the study (47 men, plus 11 women; 49 ± 15 years ( mean age ± SD)). Accident and mission characteristics The majority of the accidents occurred in the summer season whilst hiking, mountaineering, rock climbing or paragliding (Table 1). Within 44 of 58 cases (76%), fall was by far the most common underlying mechanism for injury, whereas only one case of penetrating trauma was observed (2%). Of the 58 patients, only 16 patients (28%) were evacuated from ‘easy terrain’, where specific mountaineering skills were not required for successful evacuation. Whereas, thirty-six (62%) had to be extricated from ‘difficult terrain’, where basic mountaineering experience to access the victim was required; and in 6 cases (10%), belaying of the rescuers was necessary for the evacuation. In 40 patients (69%), evacuation from the scene was possible only with help of a rope rescue operation (winch or hoist operation). Forty-seven patients (81%) were rescued solely by the HEMS crew (pilot, rescuer and emergency physician). However, in the remaining 11 patients (19%) additional terrestrial support from the TMRS was necessary, either due to adverse weather conditions or terrain difficulty obstructing direct helicopter access to the rescue site. Median pre-hospital time (time from accident to hospital admission) was 80 ± 44 minutes (median ± interquartile range; range from 28 minutes to 17 hours). In 10 patients (18%) prehospital time exceeded 120 minutes either due to delayed HEMS activation (5 patients), or prolonged access time and/or time consuming evacuation process (5 patients) (Table 2). Injury pattern Median ISS of the 58 patients reviewed was 34 ± 18 (median ± interquartile range; range 2075). Life threatening injuries (AIS Score ≥ 4), were found predominantly in the head/neck and chest regions (Table 3). ATLS Interventions at scene
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ATLS interventions at scene were performed in 57 of the 58 (98%) patients reviewed (Table 4). Only one patient had a crash evacuation to hospital solely with basic life support (BLS) interventions. An intravenous line was inserted in 57 of the 58 patients (98%). In 48 patients (83%) volume resuscitation was started at scene, with 26 patients (45%) receiving up to 500 ml volume and only 10 patients (17%) receiving more than 1000 ml volume prior to hospital admission. More than half of all patients received intravenous analgesic drugs (opioids or ketamine or a combination of both). Twenty-one patients (36%) had an endotracheal tube inserted at the scene, in 17 of those (81%) endotracheal intubation was facilitated with muscle relaxant. In one further patient repeated attempts at endotracheal intubation failed, eventually the airway of the patient was successfully managed with a laryngeal tube. No major complications of endotracheal intubation were reported. Post hospital admission, two endotracheal tubes had to be retracted from the right main bronchus, with concomitant left sided lung atelectasis evident in CT scan in both patients. In 3 patients, admission CT scan showed marked distension of the upper gastrointestinal tract due to air inflation; thus indicating problems with bag mask ventilation or endotracheal intubation at scene. ATLS interventions in patients with critically impaired vital functions Twenty-seven of the 58 patients (47%) had no critical impairment of vital functions (systolic blood pressure ≥ 90 mmHg, GCS ≥ 10 and respiratory rate between 10 - 30 BPM); as assessed by the rescue team on arrival at scene. The remaining 31 patients (53%) had at least one vital function critically impaired. In 25 of the 58 patients (43%) systolic pressure was < 90 mmHg or unobtainable, 19 patients (33%) had a GCS < 10 and 2 patients (3%) had a respiratory rate < 10 BPM. Nine of the 25 patients (36%) with an initial systolic pressure < 90 mmHg at scene, had their systolic blood pressure increase ≥ 90 mmHg on arrival to the emergency room; in 13 patients (52%) systolic blood pressure remained < 90 mmHg; whereas, three (12%) sustained cardiorespiratory arrest prior to hospital admission and subsequently died. Only 7 of all 25 patients (28%) received volume resuscitation exceeding 500 ml prior to hospital admission. Sixteen of these 25 patients (64%) had concomitantly suffered traumatic brain injury, which was verified in all cases by CT scan. In 8 of these 16 patients (50%), systolic blood pressure was increased to ≥ 90 mmHg at hospital admission. In 3 further cases with a systolic blood pressure ≥90 mmHg at rescue team arrival, blood pressure subsequently fall < 90 mmHg prior to hospital admission. One of these 3 patients sustained cardio-respiratory arrest and died at scene. Seventeen of the 19 patients (89%) with an initial GCS ≤ 9 received advanced airway management at the scene (endotracheal intubation n = 15, laryngeal tube n = 2). Whereas, two patients had a ‘crash evacuation’ (rope rescue), directly to a hospital helipad less than 5 minutes flight time away. Both with BLS airway management. Those 2 patients whom on first examination had a respiratory rate below 10 BPM, also had a GCS < 10 and both received endotracheal intubation at the scene. All patients breathing spontaneously at hospital admission had a respiratory rate between 10 - 30 BPM, plus documented oxygen saturations above 85% on hospital admission. ATLS interventions in rope rescue operations In total, 10 of the 40 patients (25%) rescued with rope rescue techniques received only BLS interventions prior to evacuation out of difficult terrain. Whereas, the remaining 30 patients (75%) all received ATLS interventions directly prior to rope evacuation. All (75%) had an intravenous line inserted, 23 patients (58%) received analgesic drugs and/or volume resuscitation, and 5 patients (13%) had an endotracheal intubation (corresponding to 50% of all endotracheal intubations eventually performed in these 40 patients prior to hospital admission). In-hospital interventions and mortality
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Immediate life-saving interventions post hospital admission (within 2h), were necessary in 14 patients (24%). Interventions included: tube thoracostomy (n = 4), emergency surgery for bleeding control (n = 3), emergency intracranial surgery (n = 4), emergency radiological intervention for bleeding control (n = 3) and implantation of an extracorporeal life support system (n = 1). Overall, four patients (7%) presented with a body core temperature ≤ 28°C on admission. Out-of-hospital mortality was recorded as 6.9% (n = 4). Whereas, in-hospital mortality equalled 10.3% (n = 6), of which 5 patients died within 12 hours of admission. Cause of early in-hospital death was irreversible neurological injury in 4 patients, 1 patient died from uncontrolled bleeding. The sixth patient died from septic multi-organ failure after a prolonged ICU stay.
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Discussion Available data concerning the pattern of injury in major trauma victims involved in mountain rescue missions are limited. Previous publications analysing mountain rescue missions included only few cases of major trauma as in the majority of mountain rescue missions, severity of injury is low with a concomitant high rate of non-life-threatening limb injuries (12, 13). This is also true for HEMS mountain rescue missions (3, 14, 15). Even in accidents involving major falls in Alpine terrain, incidence of critical trauma with an ISS > 20 is estimated at only 17.5% (16). In a necropsy study of fatal trauma after mountaineering accidents Reid et al., found a rate of traumatic brain injury of over 50% (17). Brain trauma was also the leading cause of death in this study, whereas exsanguination was uncommon (17). In contrast, Hohlrieder et al. found a low rate of severe brain trauma, but a high rate of pelvic fractures, spine fractures and major thoracic injuries in victims of major Alpine falls (16). In a study analysing casualties rescued by the Scottish Mountain Rescue Service Hearns reported a 33% early mortality rate among 12 major trauma victims, due to the severity of the underlying trauma and hypothermia (18). In review, the 58 alpine major trauma victims included in this study depicted a similar trend. Early mortality (pre-hospital or within 12 h post hospital admission) was at 15.5% and was caused by brain trauma and occasional cases of exsanguination. Major life-threatening injuries were found predominantly in the head /neck and chest region. Severe hypothermia, with a core temperature ≤28°C was present in 7% of all patients. In summary, severe brain and chest trauma as well as concomitant accidental hypothermia are common in major trauma victims involved in mountain rescue missions significantly contributing to early mortality. It is widely believed that early admission to a trauma centre within the golden hour of shock is associated with a reduced mortality and 90 minutes is the upper acceptable limit for total prehospital time recommended in the guidelines released by the German Society for Trauma Surgery (19). In this study population, despite helicopter support, total pre-hospital time exceeded 90 minutes in 44% of all mountain rescue missions. In the majority of cases, prolonged pre-hospital time was due to the necessity for rope rescue manoeuvres whilst accessing and evacuating the patient. Further delays in patient retrieval were encountered when additional terrestrial support was required to extract the patient successfully, total prehospital time often exceeding 2 hours. Despite the use of helicopters, due to the difficult terrain and adverse weather conditions often encountered in these rescue missions, prehospital times remain prolonged in many HEMS mountain rescue missions. Prolonged prehospital time is an important factor when debating the early employment of ATLS by an emergency physician at the scene (20, 21). In these remote or mountainous environments a ‘scoop and run’ concept is not an option in the majority of cases, therefore the availability of HEMS provided ATLS in major trauma victims in mountain terrain is considered potentially beneficial (20, 21).
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In the event of traumatic brain injury, the importance of protecting the airway and avoiding hypoxia and hypercapnia in affected patients, is a major proponent for early ATLS at scene (20, 22, 23). However, to date outcome data are conflicting and the actual influence of prehospital advanced airway management on morbidity and mortality of traumatic brain injury remains controversial (23, 24). In 1993 Malacrida and co-workers reported a low morbidity and mortality rate for head injury patients after mountaineering accidents when rescued by a physician staffed helicopter (9). In this case, the authors concluded that ATLS provided by an emergency physician is an effective way to reduce secondary cerebral damage in brain trauma victims in remote mountain terrain (9). Likewise, 79% of major trauma patients in this study population with a Glasgow Come Score ≤9 had their airways supported by prehospital endotracheal intubation. Traumatic brain injury with a GCS score ≤9 is considered an indication for endotracheal intubation at the scene in many emergency medical systems (EMS) (9, 19, 22, 23). In European physician staffed EMS, endotracheal intubation is currently considered the gold standard for advanced pre-hospital airway management (25, 26, 27). Correspondingly, high success and low complication rates have been repeatedly reported for pre-hospital endotracheal intubation by experienced physicians (26, 27). Equally, results of this study demonstrated that for experienced emergency physicians, pre-hospital endotracheal intubation is associated with a 90% success rate and a low rate of minor complications despite the difficulties associated with ATLS in a mountain rescue mission. More than two thirds of all endotracheal intubations in this study population were muscle relaxant facilitated. Beside extensive training and regular experience in the procedure, the use of muscle relaxants is another known factor facilitating pre-hospital endotracheal intubation (20, 23, 25). Our data demonstrated a restrictive approach in volume resuscitation in HEMS mountain rescue missions as pre-hospital volume resuscitation was below 500 ml in almost half of patients and exceeded 1000 ml in only 17%. Recent publications investigating resuscitation strategies for traumatic shock in European EMS also document low volumes of fluids being administered during pre-hospital resuscitation of trauma victims (28, 29). Currently, restrictive volume resuscitation is a widely accepted approach in normotensive multi-system trauma victims, however it is still controversial in hypotensive patients with a systolic blood pressure below 90 mmHg (30, 31). Nevertheless, within this review, 72% of patients who were reportedly hypotensive at the scene also had low volume fluid resuscitation up to 500 ml. Furthermore, a quarter of all study patients had a blood pressure below 90 mmHg on hospital admission. Both suggest a preference for a “deliberate hypotension concept” for fluid resuscitation during HEMS mountain rescue missions. The concept of “deliberate hypotension” is particularly popular in military medicine (32), but has also been recommended as therapeutic approach of choice for situations with delayed evacuation like mountain rescue missions (33). However, it is likely that low volume resuscitation was not intentional in all patients, but in some of them reflected the inability to infuse sufficient amounts of fluids in a hostile environment or during rope rescue manoeuvres. Hypertonic saline is an option to achieve blood volume expansion with lower amounts of resuscitation solution (34, 35). Therefore it may be a reasonable choice in HEMS mountain rescue missions as reduced weight and infusion volume are obviously decisive factors for the choice of resuscitation solution. The benefits of small volume resuscitation with hypertonic solutions alone or combined with dextran have been outlined for military medicine (32), but have been questioned for civilian trauma victims (34, 35). Due consideration is necessary as there is evidence that the concept of deliberate hypotension may be harmful in patients with concomitant brain trauma (22, 23, 33). Systolic blood pressure in our study population was increased to values exceeding 90 mmHg in only half of all hypotensive patients with concomitant traumatic brain injury. This shows that the treatment of prolonged pre-hospital hypotension remains an unresolved problem and indicates Page 7 of 14
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the difficulties of increasing pressure to a desired level in many cases of brain injury in a mountain rescue scenario. Although evidence to support the use of vasopressors in the treatment of haemorrhagic shock is limited, the administration of vasopressors to reverse lifethreatening hypotension has been suggested for mountain emergency medicine (33). Rope rescue operations were necessary to access and evacuate the victim in more than two thirds of all missions reviewed. Therefore, providing ATLS at the scene in HEMS mountain rescue mission will regularly necessitate involving emergency physicians in rope rescue operations. The proficiency of emergency physician in winch and hoist operations has already been highlighted mostly as a consideration in analgesic drug administration at the scene for non-life-threatening, painful injuries (3, 14, 36). Equally, the effectiveness of intravenous analgesia in mountain rescue missions has been recently demonstrated by Ellerton et al. (37). Intravenous analgesic drug administration was also necessary in more than half of the major trauma patients reviewed in this study. Sufficient patient pain relief may be crucial to ensure a rapid rescue and evacuation from technically demanding terrain, and is thus an important contribution of an emergency physician to the success and safety of the mission. Previous publications (3, 14, 36) included only occasional cases of severe trauma and therefore reported low rates of major medical interventions in rope rescue operations. Our data indicate that in case of severe trauma in HEMS mountain rescue missions, major medical interventions like endotracheal intubation are necessary and feasible on a regular basis; both in roped or non-roped rescue operations. Providing ATLS support during HEMS mountain rescue missions requires some basic alpine skills and a reasonable physical fitness of the emergency physicians involved. In Tyrol, no formal minimal requirement for alpine skill set or physical fitness exist for operational emergency physicians involved in HEMS mountain rescue missions. In fact, qualifications vary over a wide range, from rather basic alpine training to mountain guide level. Previous publications analysing wilderness and mountain rescue missions reported that ~60% of all missions require only basic technical skills as the rescue teams operated solely within a terrain of moderate grade of difficulty (12, 38). Comparable to our data, these publications also report that a small number of missions occur in extreme terrain and need belaying of the rescue team (38). To also cover these uncommon scenarios, Kueppers et al. recommend that rescue personnel involved in HEMS mountain rescue missions should be competent in rock climbing up to a difficulty of UIAA scale grade IV (38). However, in most cases of major trauma a rapid evacuation to a less exposed terrain using basic trauma life support interventions is a reasonable, if not the preferable, alternative. ICAR MEDCOM recommendations do not stipulate the need for advanced climbing and mountaineering skills in HEMS physicians involved in mountain rescue missions. The recommendations rather point out the importance of basic technical skills and physical fitness, combined with distinct qualities; such as, “being able to work under extreme conditions”, “must be comfortable in exposed situations” or “must be conscious of own safety” (4). Conclusions In review, the frequent combination of prolonged pre-hospital times, with critical impairment of vital functions, supports the need for early prehospital ATLS by an emergency physician in HEMS rescue operations in mountainous and remote areas. Pre-hospital airway protection with endotracheal intubation is possible with a high success and low complication rate, and can be accomplished in the majority of patients with severe brain trauma. Prolonged prehospital hypotension remains an unresolved problem in half of all patients with brain injury and indicates the difficulties to increase pressure to a desired level in a mountain rescue scenario. Pre-hospital volume resuscitation of hypotensive patients is restrictive and hypotension is reversed at hospital admission in only one third of patients. Despite technical considerations, for an experienced emergency physician ATLS is also feasible in the majority of rope rescue operations.
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Acknowledgement We thank Ms Rachel Turner for her support in revising the manuscript.
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References 1. Floccare D, Stuhlmiller D, Braithwaite S, Thomas S, Madden J, Hankins D, et al. Appropiate and safe utilization of helicopter emergency medical services: a joint postion statement with resource document. Prehospital Emergency Care 2013; 59:521-5. 2. Tomazin I, Kovacs T. Medical Considerations in the use of helicopters in mountain rescue. High Alt Med Biol 2003; 4:479-83. 3. Pasquier M, Geiser V, De Riedmatten M, Carron PN. Helicopter rescue operations involving winching of an emergency physician. Injury 2012; 43:1377-80. 4) 4. Tomazin I, Ellerton J, Reisten O, Soteras I, Avbelj M. Medical standards for mountain rescue operations using helicopters: official consensus recommendations of the International Commission for Mountain Emergency Medicine (ICAR MEDCOM). High Alt Med Biol 2011; 12:335-41. 5. Bakalos G, Mamali M, Komninos C, Koukou E, Tsantilas A, Tzima S, et al. Advanced life support versus basic life support in the pre-hospital setting: a meta-analysis. Resuscitation 2011; 82: 1130-7. 6. Ryynanen OP, Iirola T, Reitala J, Palve H, Malmivaara A. Is advanced life support better than basic life support in prehospital care? A systematic review. Scand J Trauma Resusc Emerg Med 2010; 18:62-76. 7. Brugger H, Elsensohn F, Syme D, Sumann G, Falk M. A survey of emergency medical services in mountain areas of Europe and North America. High Alt Med Biol 2005; 6:226-237. 8. Mair P, Frimmel C, Vergeiner G, Hohlrieder M, Moroder L, Hoesl P, Voelckel W. Emergency medical helicopters operations for avalanche accidents. Resuscitation 2013; 84: 492-5. 9. Malacrida R, Anselmi L, Genoni M, Bogen M, Suter P. Helicopter mountain rescue of patients with head injury and/or multiple injuries in southern Switzerland 1980-1990. Injury 1993; 24:451-3. 10. Strapazzon G, Costanzi E, Bonsante E, Rilk C, Mair P, Brugger H. International Alpine Trauma Registry: preliminary results for trauma life support in the mountains. Resuscitation 2013; 84 (Suppl):S S8–9.
11. Camp LV and Yates DW. Trauma Scoring. In Soreide E and Grande CM, editors. Prehospital Trauma Care. 1st ed. New York: Marcel Dekker; 1993, p. 153-168. 12. Soteras I, Subirats E, Strapazzon G. Epidemiological and medical aspects of canyoning rescue operations. Injury 2015; 46:585-9. 13. Mort A, Godden D. UK mountain rescue casualties: 2002-2006. Emerg Med J 2010; 27:309-12. 14. Moeschler O, Refondini S, Hofliger C, Freeman J. Difficult aeromedical rescue situations: experience of Swiss pre-alpine helicopter base. J Trauma 1992; 33: 754-9. 15. Kaufmann M, Moser B, Lederer W. Changes in injury pattern and severity in a helicopter air-rescue system over a 6-year period. Wilderness Environ Med 2005; 17:44-50. 16. Hohlrieder M, Eschertzhuber S, Schubert H, Zinnecker R, Mair P. Severity and pattern of injury in alpine fall accidents. High Alt Med Biol 2004; 5:349-54. 17. Reid W, Doyle D. Necropsy study of mountaineering accidents in Scotland. J Clin Pathol 1986; 39:1217-20. 18. Hearns S. The Scottish mountain rescue casualty study. Emerg Med J 2003; 20:281-4. 19. Neugebauer E, Waydhas C, Lendermans S, Rixen D, Eikermann M, Pohlemann T. Clinical practice guidelines: the treatment of patients with severe and multiple traumatic injuries. Dtsch Arztebl Int 2012; 109:102-8.
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20. Lippert F and Soreide E. The role of the physician in prehospital trauma care. In Soreide E and Grande CM, editors. Prehospital Trauma Care. 1st ed. New York: Marcel Dekker; 2001, p. 153-68. 21. Smith MR, Alasdair KT. Prehospital care – scoop and run or stay and play? Injury 2009; 40 (Suppl 4): S23-6. 22. Hoogmartens O, Haselmans A, Van de Velde S, Crasten M, Sjölin H, Sabbe M, Aertgeerts B, Ramaekers D. Evidence-based prehospital management of severe traumatic brain injury. a comparative analysis of current clinical practice guidelines. Prehosp Emerg Care 2014; 18:265-73. 23. Hammell CL, Henning JD. Prehospital management of severe traumatic brain injury. BMJ 2009; 338:b1683. 24. Elm E, Schoettker P, Henzi I, Osterwalder J, Walder B. Pre-hospital tracheal intubation in patients with traumatic brain injury: systematic review of current evidence. Br J Anaesth 2009; 103:371-86. 25. Berlac B, Hyldmo P, Kongstad P, Kurola J, Nakstad A, Sandberg M, Scandinavian Society for Anaesthesiology and Intensive Care Medicine. Pre-hospital airway management: guidelines from a task force from the Scandinavian Society for Anaesthesiology and Intensive Care Medicine. Acta Anaesthesiol Scand 2008; 52:897-907. 26. Sunde GA, Heltne JK, Lockey D, B urns B, Sandberg M, Fredriksen K, et al. Airway management by physician staffed helicopter emergency medical services – a prospective, multicentre, observational study of 2,327 patients. Scand J Trauma Resusc Emerg Med 2015; 23:57-67. 27. Thoeni N, Piegeler T, Brueesch M, Sulser S, Haas T, Mueller SM, Seifert B, Spahn D, Ruetzler K. Incidence of difficult airway situations during prehospital airway management by emergency physicians – a retrospective analysis of 692 consecutive patients. Resuscitation 2015; 90:42-5. 28. Driessen A, Froehlich M, Schaefer N, Mutschler M, Defosse J, Brockamp T, et al. Prehospital volume resuscitation – did evidence defeat the crystalloid dogma? An analysis of the TraumaRegister DGU 2002-2012. Scand J Trauma Resusc Emerg Med 2016; 24:42-50. 29. Hampton D, Fabricant L, Differding J, Diggs B, Underwood S, La Cruz D, Holcomb J. Pre-hospital intravenous fluid is associated with increased survival in trauma patients. J Trauma Acute Care Surg 2013; 75:S9-S15. 30. Geeraedts L, Pothof L, Caldwell E, Klerk E, Amours S. Prehospital fluid resuscitation in hypotensive trauma patients: Do we need a tailored approach? Injury 2015; 46:4-9. 31. Brown J, Cohen M, Minei J, Maier R, West M, Billiar T, et al. Goal directed resuscitation in the prehospital setting: a propensity adjusted analysis. J Trauma Acute Care Surg 2013; 74:1207-14. 32. Butler F. Fluid resuscitation in tactical combat casualty care: brief history and current status. J Trauma 2011; 70 (Suppl 5):S11-S12. 33. Sumann G, Paal P, Mair P, Ellerton J, Dahlberg T, Zen-Ruffinen G, Zafren K, Brugger H. Fluid management in traumatic shock: a practical approach for mountain rescue. High Alt Med Biol 2009; 10:71-5. 34. Bulger E, May S, Kerby J, Emerson S, Stiell I, Schreiber M, et al. Out-of-hospital hypertonic resuscitation after traumatic hypovolemic shock: a randomized, placebo controlled trial. Ann Surg 2011; 253:431-41. 35. Bulger E, May S, Brasel K, Schreiber M, Kerby J, Tisherman S, et. Out-of-hospital resuscitation following severe traumatic brain injury: a randomized controlled trial. JAMA 2010; 304:1455-64. 36. Sherren PB, Hayes-Bradley C, Reid C, Burns B, Habig K. Are physicians required during winch rescue missions in an Australian helicopter emergency medical service. Emerg Med J 2014; 31:229-32.
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Table 1: Recreational activities (n = 58) Activity Hiking, mountaineering Rock climbing Off-piste and Backcountry skiing/boarding Paragliding Mountain biking
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number of patients n = 19 (33 %) n = 17 (29 %) n = 13 (22.5%) n = 7 (12 %) n = 2 (3.5 %)
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37. Ellerton JA, Greene M, Paal P. The use of analgesia in mountain rescue casualties with moderate or severe pain. Emerg Med J 2013; 30: 501-5. 38. Kuepper T, Hillebrandt D, Steffgen J, Schoeffl V. Safety in alpine helicopter rescue operations– minimal requirements of alpine skills for rescue personnel. Ann Occup Hyg 2013; 57:1180-8.
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Table 2: Total pre-hospital time (n = 54) Total pre-hospital time number of patients n = 29 (54%) ≤ 90 minutes 91-120 minutes n = 14 (26%) > 120 minutes n = 10 (18 %) unknown* n = 1 (2%)
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* time of accident unknown as accident was not witnessed
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Table 3: Distribution of 72 life-threatening injuries (AIS ≥ 4) over body regions in 54 patients admitted to hospital alive body region Number of injuries ≥ AIS 4 (%) Head/ neck n = 25 (35%) face n = 3 (4%) chest n = 27 (37%) abdomen n = 5 (7%) extremities n = 12 (17%) external none
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Table 4: ATLS interventions at scene (n = 58 patients) intervention patients (%) iv line n = 57 (98 %) volume resuscitation n = 48 (83 %) volume resuscitation ≤ 500 ml volume resuscitation 500 -1000 ml volume resuscitation > 1000 ml
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iv analgesic drugs n = 31 (53 %) endotracheal intubation n = 21 (36 %) laryngeal tube/mask n = 2 (3 %) tube thoracostomy n = 2 (3%) Abbreviations: ATLS = Advanced trauma life support, iv = intravenous.
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n = 26 (45%) n = 12 (21%) n = 10 (17%)
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