Advances in Pre-hospital Care

1. Advances in Pre-hospital Care Cdrgirard Poirier, mc usn

2. Introduction • Trauma is the leading cause of death for patients up to their 4th decade of life. • Essential to optimize care for trauma patients both outside and inside the hospital setting. • Emergency Medical Services rely on advances in therapy and management. Such advances usually start in the hospital and are then carried on to the EMS system.

3. History • The concept of the modern pre-hospital care system for trauma patients goes back to the introduction of the “flying ambulances” by Napoleon's private surgeon, Dominique-Jean Larrey, in 1792. • The “flying ambulances” were horse drawn carriages, bringing physicians or medical supplies to the battlefield and transporting wounded soldiers away from the front line. • All modern EMS systems still follow this early idea of either bringing the physician to the patient or bringing the patient to the physician.

4. History • The care of trauma patients is significantly influenced by military conflicts. • Korean and Vietnam wars saw the first airborne rescue missions by helicopters on a large scale. The civilian EMS systems quickly implemented this new concept into the rescue of civilian trauma patients. • Low volume resuscitation, the revival of tourniquets, and hemostatic agents will clearly influence the care of civilian trauma patients in the future.

5. Design • Most EMS systems utilize some sort of a multi-tier approach • Some countries like Germany and France are using EMS systems which are based on the idea of bringing the physician to the patient. • EMS systems in the US are based on the premise of bringing paramedic providers, who are trained to perform a limited number of medical procedures in the field to the patients. • The emphasis is focused on rapid transport to the hospital, after the basic rescue techniques, such as airway management and fluid resuscitation, were performed at the scene.

6. Airway Management • Loss of airway or breathing is the most rapid cause of death. • The airways of severely injured patients need to be secured as soon as possible. • Airway management in the field is often more difficult than intubations in the operating room or the emergency department • Different provider training and experience, patient location, and coexisting medical or surgical problems are all factors. • Devices used in anesthesiology have been introduced to pre-hospital care providers. These devices range from laryngoscopes and different laryngoscope blades to oral and nasal airways. More recently introduced devices include the elastic bougie, and even more recently, supraglottic devices.

7. Airway Management • Endotracheal Intubation: As stated, can be difficult in the field setting Standard equipment may not be adequate to secure an airway Devices have been developed to aid in difficult and failed intubation attempts.

8. Airway Management • Glidescope Provides direct visualization of airway structures. Rigid, preformed Stylet used with ETT

9. Airway Management • Multiple other visually assisted devices are available. • Ambu® Pentax Airway Scope • C-MAC® Video Laryngoscope • McGrath® Video Laryngoscope

10. Airway Management • Elastic Bougie. Used by anesth. Since 1949. Now readily available to EMS providers to aid in intubations. • “ride” the glottis into the trachea • Can easily feel tracheal rings with tip of bougie. • ETT placed over bougie

11. Airway Management • Supraglottic Device. Laryngeal Mask Airway (LMA). No visualization required. Easily inserted • Tip over esoph with balloon inflating over glottis • Not a definitive airway

12. Airway Management • CombiTube: Dual balloon device Easy inertion Not definitive

13. Airway Management • King LT Dual balloon, supraglottic device Single inflation port as compared to the Combitube. Not definitive Gastric access available

14. Airway Management • Studies in the US showing increased risk of morbidity and mortality with pre-hospital RSI / intubation • Increased in pediatric and TBI populations • Paradigm may shift to non-definitive airways in these poplations • Further study required

15. Circulatory Access • Paramedics and other prehospital providers have been placing intravenous access as a standard treatment since the beginning of pre-hospital care. • Certain patients such as hypovolemic patients, intravenous drug abusers, burn patients, and children, peripheral intravenous access may not be possible

16. Circulatory Access • Intraosseous Access: FAST IO

17. Circulatory Access Intra-Osseous Easy IO Proximal and distal Tibia, ProxHumerus

18. Circulatory Access • Pitfalls to intraosseousaccess: • is the increased infection risk • blood products cannot be given through this access. • the patient still requires intravenous access one at the hospital and the intraosseousneedle (or needles) needs to be removed. For this reason, intraosseous access is often used as a last resort when peripheral IV access can not be established in the field.

19. Hemorrhage Control • Tourniquets : • Are experiencing a revival after they were all but eliminated in the early 80s when the fear of extended soft tissue damage, nerve damage and the potential loss of the extremity was feared if the tourniquet was used for too long. • The different types of tourniquets (rubber, cloth, and windlass) are successful in eliminating distal pulses when applied above and below the knee or elbow. The location of the tourniquet may allow a lower amputation with preservation of the joint

20. Hemorrhage Control • Hemostatic Dressings: • HemCon®bandage: becoming extremely adherent when in contact with blood. This adhesive-like action seals the wound and controls bleeding. Multiple patch sizes.

21. Hemorrhage Control • QuickClot®ACS / CombatGauze (Hemostatic Dressing) • Fluid molecules are adsorbed by the QuikClotACS™material. This causes rapid localized coagulation and the formation of a stable blood clot • Exothermic reaction may occur if excessive water is present on wound site. • Utilized by US Military

22. Hemorrhage Control • Granular Agent: WoundStat: Absorbs water and forms a claylike seal within the wound Found to be superior at hemostatis However, further studies have shown signif inflammatory rxn, neurovasc changes. Granules have the potential of traveling intravasc. Removed from use by US military

23. Monitoring • End Tidal CO2 Monitoring: • Introduced in many EMS systems and the emergency room as a way to verify tracheal position of an ETT. • Also useful in guiding mechanical ventilation, especially when transport ventilators are used in which the minute volume can be better controlled than in manual bag ventilation. • Assessment of effectiveness of cardio pulmonary resuscitation (CPR), as larger volumes of end-tidal CO2 indicate not only effective ventilation but also better cardiac output

24. Monitoring • End Tidal CO2 (continued): • End-tidal capnography in the prehospital setting can reduce the incidence of severe inadvertent hyperventilation by over 50% Davis DP, Dunford JV, Ochs M, Park K, Hoyt DB. The use of quantitative end-tidal capnometry to avoid inadvertent severe hyperventilation in patients with head injury after paramedic rapid sequence intubation. J Trauma. 2004;56:808–14 • In intubated patients with traumatic brain injury, the survival rate was increased twofold when the arrival pCO2 was between 30 and 49 mm Hg Davis DP, Idris AH, Sise MJ, Kennedy F, Eastman AB, Velky T, et al. Early ventilation and outcome in patients with moderate to severe traumatic brain injury. Crit Care Med. 2006;34:1202–8

25. Artificial Blood Products • “Every minute of every day, someone needs blood.” • The Military use was the primary driver to develop blood substitutes. • Public concern over blood safety, particularly from an infectious diseases standpoint. • Increased utilization of blood products by a growing and ageing population, compounded by increasing complexity of medical and surgical treatments

26. Artificial Blood Products Advantages of Blood Substitutes • Universally compatible • Pure and non‐toxic • Stability and shelf life • Rapid and widespread availability

27. Artificial Blood Products Two major oxygen‐based substitutes 1) BiomimeticApproach: Hemoglobin Based Oxygen Carriers (HBOCs) 2) Abiotic Approach: Perfluorocarbon Emulsion (PFCEs)

28. Artificial Blood Products HBOC’s • Hemopure – crosslinked bovine polyHb • Hemolink – crosslinked human oligoHb • PolyHeme – crosslinked human polyHb • Hemospan –PEG modified human Hb • HemoZyme – polynitoxylated human Hb • Optro – recombinant human Hb

29. Artificial Blood Products Hemopure in the Trauma Setting • Currently in use in South Africa, approved 2001 • In U.S., found not to be inferior to blood • FDA suspended human trials due to safety concerns mainly from vasoconstrictive responses to infusion. • Studies have been proposed to co-infuse a nitric oxide donor such as nitroglycerin in a fixed ratio, in a single-bag compound, or as a separate infusion. There is little likelihood that trauma surgeons will accept a product developed to treat shock that requires co-infusion of a vasodilator.

30. Artificial Blood Products • Other HBOC’s • Sixteen trials involving 5 different products and 3711 patients in varied patient populations were identified. Overall, there was a statistically significant increase in the risk of death (164 deaths in the HBBS-treated groups and 123 deaths in the control groups; relative risk [RR], 1.30; 95% confidence interval [CI], 1.05-1.61) and risk of MI (59 MIs in the HBBS-treated groups and 16 MIs in the control groups; RR, 2.71; 95% CI, 1.67-4.40) with these HBBSs. Subgroup analysis of these trials indicated the increased risk was not restricted to a particular HBBS or clinical indication. • CONCLUSION: Based on the available data, use of HBBSs is associated with a significantly increased risk of death and MI. Nathanson C. Cell-free hemoglobin-based blood substitutes and risk of myocardial infarction and death: a meta-analysis. JAMA 2008 May 21;299(19):2304-12

31. Artificial Blood Products • Perflurocarbon Emulsions: • Current PFCE products are referred to as second generation PFCE's and are marketed as oxygen therapeutics for patients at risk of acute hypoxia resulting from transient anemia, blood loss or ischemia. • Data from numerous studies, including a European Phase III study of 492 patients investigating the use of Oxygent™ in general surgery, showed that the product reduced the need for transfused blood. While a Phase III trial involving CABG in the US was halted due to high stroke rates in both the experimental and control groups, Alliance is hoping to initiate further Phase III studies involving general surgery. • Currently, there are four US clinical sites involved and SYBD hopes to eventually have six. Future Phase II trials will involve the use of Oxycyte™ in CABG, and heart valve replacement surgery, among others.

32. A Few Controversial Topics • EMS / Field Intubation: • The effect of paramedic rapid sequence intubation on outcome in patients with severe traumatic brain injury. • J Trauma. 2003 Mar;54(3):444‐53. Davis DP, Hoyt DB, Ochs M, Fortlage D, Holbrook T, Marshall LK, Rosen P.Department of Emergency Medicine, UC San Diego, CA 92103‐8676, USA.

33. Controversies • OBJECTIVE: To evaluate the effect of paramedic rapid sequence intubation (RSI) on outcome in patients with severe traumatic brain injury. • • METHODS: Adult major trauma victims were prospectively enrolled over two years • RESULTS: A total of 209 trial patients were hand matched to 627 controls. The groups were similar with regard to all matching parameters, admission vital signs, frequency of specific head injury diagnoses, and incidence of invasive procedures.

34. Controversies • Results : • Mortality was significantly increased in the trial cohort versus controls for all patients (33.0% versus 24.2%, p < 0.05) • Factors that may have contributed to the increase in mortality include transient hypoxia, inadvertent hyperventilation, and longer scene times associated with the RSI procedure

35. Controversies • Cochrane Review (9 studies to date) • Quite a few studies have been conducted to address the question of prehospital endotracheal intubation in major trauma victims needing airway management. All of them are of retrospective design • most of them show that there is increased mortality • longer transit times with prehospital endotracheal intubation. The reasons could be difficulty in ascertaining tube position, • paramedic experience, • hyperventilation, • transient hypoxia, or • lack of sufficient pre‐oxygenation prior to RSI. • Clinical Bottom Line ‐ Prehospital endotracheal intubation is associated with increased mortality in patients with moderate to severe traumatic brain injury

36. Controversies • Spine Immobilization • Previous studies have suggested that prehospital spine immobilization provides minimal benefit in pts with penetrating trauma • Haut ER, et al. Spine Immobilization in Penetrating Trauma: More Harm Than Good? J Trauma. 2010 Jan;68(1):115‐121

37. Controversies • 45,284 pts with penetrating trauma retrospectively analyzed8.1% overall mortality • 4.3% underwent spine immobilization. Unadjusted mortality was double in spine‐immobilized pts (14.7% vs 7.2%, p<0.001) • OR of death those was 2.06 (95% CI: 1.35‐3.13) • Only 30 pts (0.01%) had incomplete spinal cord injury and needed operative treatment • NNT to potentially benefit one pt = 1032 • NNH to potentially contribute to one death = 66

38. Controversies Harmful or Helpful ? • Comes down to EMS medical treatment protocols • Good decision making by ALS providers • Nexus Criteria for Spine Immobilization • Midline cervical pain • Neurologic deficit • Mental status change • Distracting injury • ETOH or Drug use association

39. Controversies • Does Helicopter Transport of trauma patients improve outcomes? • A topic of much discussion • Multitude of studies with results for and against. • Which has the best studies • Number of medical helicopters has doubled in the last 4 years in the US.

40. Controversies • Air versus ground transport of the major trauma patients: a natural experiment McVey J, Petrie DA, Tallon JM. Department of Emergency Medicine, Dalhousie University, Nova Scotia, Canada. mcveyj@dal.caPrehospitalEmerg Care. 2010 Jan-Mar;14(1):45-50 • compared the outcomes of adult trauma patients transported to a level I trauma center by helicopter vs. ground ambulance. • Retrospective database review • Air transport of the adult major trauma patient is associated with significantly improved survival as compared with ground transport.

41. Controversies • Air versus ground transport of major trauma patients to a tertiary trauma centre: a province‐wide comparison using TRISS analysis Alex D. Mitchell,* John M. Tallon,† and Beth Sealy†From the *Division of General Surgery and the †Nova Scotia Trauma Program, Queen Elizabeth II Health Sciences Centre, Dalhousie University, Halifax, NS. Can J Surg. 2007 April; 50(2): 129–133 • The transport of trauma patients with an ISS ≥ 12 by a provincially dedicated rotor wing air medical service was associated with statistically significantly better outcomes than those transported by standard ground ambulance. This is the first large Canadian study to specifically compare the outcome of patients transported by ground with those transported by air. • Retrospective analysis of 823 trauma patients

42. Controversies • Shatney CH, Homan SJ, Sherek JP, et al. The utility of helicopter transport of trauma patients from the injury scene in an urban trauma system. J Trauma. 2002;53(5):817-22 • 10-year retrospective review of 947 consecutive trauma patients transported to the Santa Clara Valley trauma center. • Blunt trauma: 911 • Penetrating trauma: 36

43. Controversies • Only 17 patients (1.8%) underwent surgery for immediately life-threatening injuries. • Helicopter arrival faster = 54.7% • Helicopter arrival slower = 45.3% • Only 22.4% of the study population were possibly helped by helicopter transport. • CONCLUSION: The helicopter is used excessively for scene transport of trauma victims in our metropolitan trauma system. New criteria should be developed for helicopter deployment in the urban trauma environment

44. Controversies • Eckstein M, Jantos T, Kelly N, et al. Helicopter transport of pediatric trauma patients in an urban emergency medical services system: a critical analysis. J Trauma, 2002;53:340-344. • Retrospective review of 189 pediatric trauma patients (<15) transported by helicopter from the scene in LA. • Median age: 5 years • RTS > 7 = 82% • ISS < 15 = 83% • Admitted to ICU = 18% • Discharged from ED = 33%

45. RTS - Revised Trauma Score GCS Points SBP Points RR Points 15-13 4 >89 4 10-29 4 12-9 3 76-89 3 >29 3 8-6 2 50-75 2 6-9 2 5-4 1 1-49 1 1-5 1 3 0 0 0 0 0 The score range is 0-12. In STARTtriage, a patient with an RTS score of 12 is labeled delayed, 11 is urgent , and 10-3 is immediate. Those who have an RTS below 3 are declared dead and should not receive certain care because they are highly unlikely to survive without a significant amount of resources.

46. ISS – Injury Severity Score • The Injury Severity Score (ISS) is an anatomical scoring system that provides an overall score for patients with multiple injuries. Each injury is assigned an Abbreviated Injury Scale (AIS) score and is allocated to one of six body regions (Head, Face, Chest, Abdomen, Extremities (including Pelvis), External). Only the highest AIS score in each body region is used. The 3 most severely injured body regions have their score squared and added together to produce the ISS score • The ISS scores ranges from 1 to 75 (i.e. AIS scores of 5 for each category). If any of the three scores is a 6, the score is automatically set at 75. Since a score of 6 ("unsurvivable") indicates the futility of further medical care in preserving life, this may mean a cessation of further care in triage for a patient with a score of 6 in any category.

47. Controversies • CONCLUSION: The majority of pediatric trauma patients transported by helicopter in our study sustained minor injuries. A revised policy to better identify pediatric patients who might benefit from helicopter transport appears to be warranted

48. Controversies • Helicopter emergency medical services for adults with major trauma Galvagno SM. Cochrane Database Syst Review. 2013 Mar 28;3 • 25 studies reviewed • No randomized trials, significantly flawed methodology in most. Groups not well matched and heterogeneous. • 5 studies focused on TBI, no change in mortality with HEMS • Other studies were mixed • Difficult to draw conclusions.

49. Controversies • Majority of data does show that helicopters are over utilized for trauma scene responses especially in pediatric patients. • Over triage of trauma patients primary factor • Costs and risks may not justify benefit for the vast majority of trauma patients. • Triage criteria should be based on physiological parameters and not mechanism of injury.

50. Controversies • Medical helicopters accept the most dangerous missions in commercial aviation. They fly unplanned routes a few hundred feet above the ground, often below radar. They land on highways, mountains and farms, miles from the nearest airport weather stationThe majority have no autopilot system or co-pilot to assist the pilot in emergencies. Medical helicopters are not required to have terrain awareness and warning systems (TAWS), night-vision goggles, flight data recorders, detailed weather reporting or ground personnel in charge of flight dispatch and in-flight tracking. medical helicopters crash at twice the rate of other air taxis and are exponentially more dangerous than commercial airliners, according to a 2009 study by Ira Blumen, medical and program director of the University of Chicago Aeromedical Network. Air ambulances have crashed 272 times between 1972 and 2010, killing 276 people.