Trauma is one of the major causes of mortality and morbidity in India, especially during the productive years of life, i.e., 15–30 years of age group. The World Health Organization's (WHO's) statistics clearly show that the developing world contributes the most to the number of trauma victims with >90% of the road traffic accidents (RTA) occurring here. This could be due to the lack of public awareness on safety, lethargy in the government mechanism to impose safety regulations, lack of coordinated prehospital care for trauma victims, lack of standardized trauma training for medical personnel, and nonavailability of dedicated trauma team or center for the care of the injured.
Trauma kills in a very predictable manner. The concept of a “Trimodal” death pattern in trauma is well recognized and it consists of three peaks of death during the natural course of recovery of an injured person. The first peak occurs immediately following the event and is usually due to apnea caused from severe brain or high spinal cord injury or rupture of the heart or one of the large vessels. Only few of these patients can be saved and that too by putting in place preventive measures. The second peak of death happens minutes to hours after the injury and is due to lesions such as subdural hematoma, extradural hematoma, hemopneumothorax, ruptured spleen/liver, fractured pelvis, and any other injury that causes significant blood loss. Rapid focused assessment and resuscitation in a coordinated manner can reduce death during this period. The third peak occurs days to weeks after the injury and is usually due to secondary infection, sepsis, and multiorgan dysfunction. In a trauma victim, loss of airway (A) kills quicker than the inability to breathe (B), which kills faster than loss of blood volume (C), followed by an expanding intracranial mass/hematoma (D). This predictable and reproducible manner in which injuries kill their victim has been incorporated into the trauma resuscitation algorithm. The emphasis is on treating the greatest threat to life first. This has generated the ABCDE approach to trauma resuscitation. Resuscitation during the “Golden hour” of injury, which is not meant to indicate a fixed time period during which the resuscitation would work but the urgency required for initial assessment and successful treatment of the injured victim has shown to be associated with decrease in mortality and morbidity.
Planning well ahead to receive trauma patients to a hospital is very important and for this coordination with prehospital personnel at the scene of the trauma is absolutely essential. This could also help with the initiation of the resuscitation at the site. During the prehospital phase, emphasis should be placed on maintaining the airway, immobilizing the spine, controlling of the external bleed, treating shock, and immediate transport to the hospital minimizing the time spent at the scene to as little as possible. Hospitals that accept the trauma victims should be well prepared to receive them. A smooth handover should be taken from the prehospital personnel making sure that all the vital information required for the rapid resuscitation, such as time of injury, mechanism of injury, events related to the injury, any loss of life at the scene, treatment provided at the scene, and any other vital history that is known, are collected. A resuscitation area should be kept ready and all articles required for “Standard precaution” (face mask, eye protection, gloves, water impervious gown, etc.) are made available. The list of equipment needed for a trauma resuscitation room is exhaustive and the WHO has laid down a simple checklist of essential emergency equipment for resuscitation. The minimum requirements would be a facility for oxygen therapy, suction apparatus, functional airway equipment, warmed intravenous fluids, wide-bore intravenous cannulae, basic splints, and appropriate monitoring facility. All necessary personnel should be mobilized and be ready to accept the victims in the emergency room. The hospital should develop written protocol for prompt responses from the medical team, laboratory, and the radiology departments.
INITIAL ASSESSMENT AND RESUSCITATION: PRIMARY SURVEY
There are certain thumb rules in the initial assessment and resuscitation of trauma patients. The assessment has to be rapid with resuscitation of the greatest threat to life done first. There is no need for a detailed history to initiate therapy and physiological derangements need to be fixed as they are found. This is the principle of primary survey and this has to happen in the following prioritized sequence:
- A: Airway maintenance with restriction of cervical spine movement
- B: Breathing with ventilation
- C: Circulation with bleeding control
- D: Disability—neurological
- E: Exposure/environment control.
The quickest way to assess ABCDE is by asking the patient his/her name and what had happened. An appropriate response suggests, in less than 10 seconds, that there is no major airway, breathing, circulation, or consciousness problem. Physiological changes that occur in trauma are very dynamic and a patient who is initially stable can deteriorate rapidly. Frequent revaluation of ABCDE are of paramount importance until definitive therapy has been accomplished.
Airway Maintenance with Restriction of Cervical Spine Movement
All patients with trauma should receive oxygen therapy at 10 L/min given through a mask-reservoir device. If patient is able to talk his/her airway is maintained and needs no airway protection. However, if the patient is not talking, do an in-line stabilization maneuver to restrict cervical spine movement before assessing the airway any further. First, inspect the face to look for any obvious injuries that could obstruct the airway. Then open his/her mouth and inspect inside for any foreign bodies, blood, or secretions that could obstruct the airway. Remove any foreign body, suction the oral cavity and throat clear of all secretions. Reassess the airway patency again and listen for any sonorous noise. If the airway is still compromised do a chin lift/modified jaw thrust maneuver to see if this would open the airway. If it does not and cause for the loss of airway can be rectified quickly, place an oropharyngeal airway. Otherwise think of placing a definitive airway, such as an orotracheal intubation.
In the meanwhile, continue with in-line stabilization maneuver until a semirigid cervical collar is applied. Prior to application of the semirigid collar, inspect and palpate the neck to look for any injuries, dilated veins, tracheal shift, or subcutaneous air. The decision to apply or discontinue the cervical semirigid can be made by using clinical decision screening tools such as Canadian C-spine Rule and the NEXUS (National Emergency X-radiography Utilization Study).
After having done these, reassess again to make sure the airway is secure and patent.
Breathing with Ventilation
After the airway is secured, make sure that the breathing and the ventilation are adequate to ensure proper oxygenation and carbon dioxide removal. Injuries that significantly impair ventilation and can be rapidly fatal are:
- Tension pneumothorax
- Massive hemothorax
- Open pneumothorax
- Tracheal/bronchial injuries.
These injuries need to be identified in the primary survey and attended to immediately to prevent mortality. This can be done by completely exposing the chest and neck, if not already done so during the evaluation of the airway. Then go through the four simple steps of:
- Look: Look at the chest wall for any obvious injuries. An open sucking wound would suggest an open pneumothorax. Soft-tissue abrasions could suggest possible injury to deeper structures over that site. Look at the chest movement and count the respiratory rate. Look for paradoxical movement of the chest. If not already done, undo the cervical collar and with in-line manual stabilization of the cervical spine inspect the neck for dilated veins.
- Listen: Auscultate to listen for presence or absence of breath sounds. The latter could suggest a pneumothorax or hemothorax. Corroborate this finding with that found on inspection, palpation, and percussion.
- Percussion: Percussion is done over the chest looking for resonant, hyperresonant, or dull percussion notes in an attempt to recognize a pneumothorax, tension pneumothorax, and a hemothorax, respectively. These findings need to be corroborated with the findings in inspection, auscultation, and palpation to reach at a diagnosis.
- Feel: Palpate the neck and chest carefully feeling for any tenderness, bony crepitus, or air crepitus. This will help in identifying fractured ribs and subcutaneous emphysema.
The less critical injuries, which can be missed if primary survey is not done carefully and then can affect ventilation to varying degrees, are:
- Simple pneumothorax
- Simple hemothorax
- Fracture ribs
- Flail chest
- Pulmonary contusion
To make sure that oxygenation and ventilation targets are being met, the following monitoring should be initiated:
- End tidal carbon dioxide (EtCO2) monitoring—if available, especially once patient is intubated, helps with assessing the ventilation.
After having completed these, reassess the patient to make sure airway, cervical spine immobilization, breathing and ventilation are stable.
Circulation with Bleeding Control
Shock is a situation where circulatory compromise leads to hypoperfusion of the tissues and it is a major reversible cause of mortality in trauma. Hemorrhage causing hypovolemia is the most common cause of shock in trauma. However, tension pneumothorax and pericardial tamponade, both causing obstructive shock should not be missed. Recognizing shock, especially in its very early stages, is absolutely crucial. The important signs to look for are:
- Postural hypotension: This is one of the first signs of shock. However, it is very often missed as it may be impossible to perform on trauma patients.
- Pulse: Tachycardia with rapid and thready pulse is quite suggestive of hypovolemic shock.
- Supine hypotension: This sets in later, with the loss of large volume of blood and is characterized by a narrow pulse pressure.
- Skin: Skin would be cool to touch. Face can be ashen and extremities pale.
- Decreased urine output: Indicates decreased organ perfusion.
- Altered mental status: Indicates poor organ perfusion.
If facilities for measuring lactate levels and base excess are available, they can be used to assess circulatory compromise. A raised serum lactate or base excess is a sensitive indicator of shock.
Once a circulatory compromise has been identified resuscitation has to be prompt and rapid. It is equally important to identify the site of bleed and to stop it. Resuscitation of a trauma victim in shock consists of:
- Appropriate replacement of intravascular volume: To achieve this, place two wide-bore peripheral catheters, which are more than 18 gauge. Draw blood for hematological tests, coagulation parameters, blood grouping and crossmatching, and pregnancy test for women in their reproductive age group.When peripheral venous access is not achievable, intraosseous, central venous, or venous cut down can be considered.Fluid administration should be judicious. Aggressive fluid resuscitation before the control of bleeding has been shown to increase mortality and morbidity. Start intravenous fluid therapy with crystalloids warmed to 37–40°C. Administer 1 L of the solution as a bolus and check for hemodynamic response. Based on the response to this fluid bolus trauma victims can be classified into being responders, transient responders, or nonresponders (Table 1). Transient and nonresponders to the initial fluid bolus should be started on blood transfusion.
- Hemostatic resuscitation: Start blood product transfusion in transient and nonresponders early. If the victim requires more than two units of packed red blood cells (PRBC), combining it with balanced ratio of plasma and platelet concentrates have been shown to decrease the incidence of coagulopathy and improve mortality.
- Stopping the bleed: Hemorrhage control is a very important aspect of resuscitation. To achieve this, the source of bleed needs to be identified.External bleed can be identified on inspection. The source of bleed can be controlled by:
- Direct manual pressure over the wound
- Packing of the wound: This can be done with ordinary gauze or, if available, one impregnated with hemostatic agent
- Application of tourniquets: Tourniquets are applied to extremities where the injury is causing massive bleed that cannot be stopped with direct manual pressure and packing. There is a risk of causing ischemia to the limb.
Internal bleeds should be suspected when blood is not seen on the floor. The chest, abdominal cavity, retroperitoneum, pelvis, and long bones are the main areas where hemodynamically significant bleeds can occur. The source should be suspected and identified by the use of adjuncts. Despite a thorough search, if the source of bleed cannot be found, consider log rolling the patient and inspecting his/her back and gluteal region for any injuries that could explain the loss of volume. Lifesaving procedures such as chest decompression, use of pelvic stabilization devices and extremity splints should be performed as indicated, while surgical interventions such as laparotomy and use of interventional radiology techniques may require expertise and transfer of the patient to a higher center.
- Early treatment of coagulopathy: Severely injured trauma victims are at a high risk of developing coagulopathy and up to 30% of them are coagulopathic by the time they arrive to the hospital. This has to be suspected and coagulation parameters checked as soon as they arrive to the emergency room (ER). Coagulopathy can be reduced by early use of blood product transfusion in a balanced ratio of PRBC:plasma:platelet concentrate. If the victim requires massive blood transfusion (MBT), use of MBT protocols with blood products administered in a predefined ratio (Table 2) helps in reducing incidence of coagulopathy. The use of point-of-care testings such as thromboelastography (TEG) and rotational thromboelastometry (ROTEM), if available, will help in deciding what blood products to use. The use of tranexamic acid in prehospital setting, in patients at high risk for developing coagulopathy, has shown to decrease mortality. If used in the field, this needs to be followed up with another dose in the hospital.
- Resuscitation to a hemodynamic target: The aim of resuscitation is to correct overt signs of hypovolemia and hidden hypoperfusion. There is evidence that over-resuscitation is harmful. Fluid resuscitation of >1.5 L in the ER was associated with higher mortality and delaying fluid resuscitation until definitive surgical control of bleed in a penetrating torso injury had improved outcomes.
Table 2 Example of a MBT protocol transfusion.PackagePRBC (units)Plasma (units)Platelets (apheresis) (units)Cryoprecipitate (units)Initial66166126620366146610566166610The recommendation is resuscitation to a target systolic blood pressure of 80–100 mm Hg until definitive therapy, in patients without head injury. This is termed “Hypotensive Resuscitation.”
All through the resuscitative phase, it is important to make sure that the trauma victim is kept free of hypothermia, acidosis, and coagulopathy. These three events form the “Lethal Triad” that increases mortality.
To make sure that the hemodynamics and tissue perfusion are being maintained and the source of bleeding identified, the following adjuncts will be useful:
- A continuous ECG monitor
- A blood pressure monitor
- Access to arterial blood gas machine: To check serum lactate and base excess.
- X-rays of the chest and pelvis: These are the only two X-rays that are part of the primary survey.
- Point-of-care ultrasound machine (for FAST/eFAST assessment): FAST/eFAST helps with assessment of fluid collection in the abdomen, pleural cavity, and the pericardial cavity. It also helps diagnose pneumothorax and lung contusion.
- Urinary catheter has to be placed with caution and avoided if a urethral injury is suspected, by the presence of blood in urethral meatus or perineal ecchymosis.
- Gastric tube is placed preferably through the orogastric route, especially if there is suspected base of skull injury. It helps to decompress the stomach and to assess for bleeding.
After having completed these reassess the patient to make sure that airway, cervical spine immobilization, breathing, ventilation, source of bleed and circulation are stable.
Disability: Rapid Neurologic Evaluation
Disability assessment, in primary survey, mainly assesses the neurological disability and it consists of only three factors:
- Assessment of pupil size and reaction: Difference in pupil size and reaction to light stimulus will help in suspecting and localizing an intracranial lesion.
- Assessment for lateralizing signs: This helps in suspecting a spinal cord injury and its level.
- Glasgow coma scale (GCS) assessment: GCS is an objective method of assessing level of consciousness. A decreased GCS indicates a lower level of consciousness and the motor score correlates well with outcomes. A low GCS could be due to a direct cerebral injury or a decreased cerebral oxygenation/perfusion. When this is noted, reevaluation of the patient's oxygenation, ventilation, and perfusion is essential.
A CT scan of the brain is not a part of the primary survey and all patients with traumatic brain injury do not need CT scan of the brain (Box 1). Time should not be wasted on doing CT scan of the brain, especially if there is no inhouse expertise and facilities to deal with the neurosurgical problem.
All arrangements should be made to stabilize the patient and he/she should be transferred to a higher center with neurosurgical backup, as soon as possible.
The main aim in primary survey is to prevent secondary injuries to the neurological system. Until proven otherwise, always consider a change in level of consciousness to be a result of brain injury. Make sure that oxygenation and perfusion are adequate and events such as fever, hypoglycemia, and seizure that can injure the brain further are avoided. Neurosurgical consultation should be obtained early.
At the end of assessing disability, go back and reassess to make sure that airway, cervical spine immobilization, breathing, ventilation, source of bleed, circulation, and neurological status are stable.
Exposure and Environment
As a part of the primary survey, the trauma victim should be completely undressed and examined and quickly examined from head to toe. Look and feel/palpate for any missed injuries. Do not forget to inspect the perineal and gluteal regions that are very often avoided and injuries are missed. After completing the examination, the patient should be covered with warm blankets.
Maintain the environment warm as all trauma victims, especially if they are bleeding, have a tendency to become hypothermic. It is not the comfort of the medical personnel that is important but the patient's body temperature. Monitor the victim's body temperature closely and aggressively bring it back to normal by using blankets, warmers, and warmed intravenous fluids.
At the end of assessing exposure/environment, go back and reassess the patient to make sure that the airway, cervical spine immobilization, breathing, ventilation, source of bleed, circulation, neurological status, and patient environment are all stable.
All through the primary survey, a continuous assessment should be made if the hospital has the capability of meeting the patient's need for definitive care. If it doesn't, transfer to a higher center should be considered. Decision about transferring the patient should be made only after completion of the primary survey and the patient has become stable. Transfer should be only to a higher center that has capabilities to provide definitive care. Prior to transfer, the treating doctor should communicate with the team leader at the receiving hospital to provide him/her with all patient details and to make sure that they are ready to accept the patient. He should also, with the help of the receiving team, decide on the mode of transport used for the transfer and make necessary arrangements to make sure that the patient receives the same level of care during the transfer that he requires in the ER. The patient should then be transferred after obtaining consent for the procedure from the patient or/and his family, with all the documents needed for continuing his/her care in the higher center.
Secondary survey is initiated only after primary survey is completed and patient's ABCDE are stable. It consists of a head-to-toe, comprehensive evaluation of patient, examining each region of the body and each system thoroughly. Any investigation that is needed to arrive at a diagnosis is made use as an adjunct.
A complete history that elucidates the mechanism of injury has to be obtained. This helps with anticipating and looking for possible injuries, which are then classified as blunt or penetrating. To help with obtaining the history, the mnemonics “AMPLE” can be used where:
- A: Allergies
- M: Medications that is being currently used
- P: Past illness/pregnancy
- L: Last meal
- E: Events/environment related to the injury.
The examination of the patient can start with inspecting and palpating the scalp for any injury. Lacerations and fractures of the skull should be looked for, especially by passing the fingers behind over the occiput and the mastoid region. Palpate every inch of the face looking for similar injuries of the supraorbital ridge, orbit, zygoma, maxilla, mastoid, and mandible. Examine the eyes carefully for any injury to the globe, look at the pupils and the fundus. Examine the ears for hemotympanum and nose for rhinorrhea. Open the mouth and look for any broken teeth or alveolar fracture. Use available imaging modalities such as CT scan of the head and face to confirm the diagnosis.
Apply the Canadian C-spine Rule and NEXUS to help with the decision about the cervical spine immobilization device removal. Inspect and palpate the neck looking for injuries, dilated neck veins, subcutaneous emphysema, and tracheal deviation. Feel for both carotid pulses and auscultate for any bruit. If any vascular injury is suspected, consider carotid Doppler studies and CT scan of the neck with angiography.
Log roll the patient and examine the spine looking for tenderness, step up or step down deformities and any other injuries. A detailed neurological examination looking at the dermatomes and myotomes to try and localize the level of spinal lesion is done. A MRI scan of the spine can be done, if a spinal injury is suspected. Patients should be on spinal protection until spinal injury has been ruled out.
Other regions in the body such as the chest, abdomen, pelvis, perineum, rectum, vaginal, musculoskeletal system, and neurological system are also examined comprehensively looking for injuries. After completing secondary survey, the victim proceeds to have definitive therapy for all injuries that have been identified.
The ABCDE approach, even though taught as a sequential assessing method, which can be applied effectively even in resource-limited settings with few medical personnel is usually done in a parallel method when there is a trauma team of four to five medical personnel, with each member of the team taking up a responsibility (Flowchart 1).
The aim of primary survey is to rapidly assess trauma victims for life-threatening injuries and to resuscitate these injuries as they are found. This systematic approach of resuscitation has shown to decrease mortality. The key to primary survey is to reevaluate the victims frequently as trauma is a dynamic situation and constant vigil is necessary to make sure that injuries that have been stabilized remains stable. Once the victim is stable, a decision to transfer him/her to a higher center for definitive care needs to be taken without wasting precious time on unnecessary investigations. Secondary survey should be initiated only after primary survey has been completed and the victim is stable. After secondary survey, the victim proceeds to definitive care.
MULTIPLE CHOICE QUESTIONS
- Trauma deaths happen in a reproducible and predictable manner. Which of the following injuries would cause death the fastest?
- Extradural hematoma
- Fracture of pelvis
- Laceration of the liver
- Facial injury with blood in the pharynx obstructing the airway
- Multiple rib factures
- Ans. d
- A 28-year-old motor bike rider who had lost control of his bike and collided into a wall is brought to the emergency room (ER) by the ambulance crew. They report that he was unconscious at the scene, but had woken up en route. His pulse rate is 100/min and his blood pressure recorded by them is 120/80 mm Hg. The first thing that needs to be done for him is:
- Wait to assess him until a complete reliable history is available
- Get a CT scan of the brain immediately
- Intubate him
- Place a semirigid cervical collar
- Give him oxygen through a mask-reservoir device at 10 L/min
- Ans. e
- A 40-year-old man, a driver in a motor vehicle accident, is brought into the ER by the ambulance crew on a spine board, with cervical collar on, an 18G-intravenous cannula on the left forearm with intravenous normal saline on flow and oxygen flowing at 10 L/min through a face mask. On arrival, his GCS is 15, but a laceration is noticed on the right side of his forehead and he is complaining of right-sided chest pain. He is moved immediately to the radiology department for a CT scan of the head and a chest X-ray. On returning from the radiology department, his GCS is noticed to have dropped to 5. Further examination reveals his pulse rate to be 130/min, blood pressure is 100/80 mm Hg and respiratory rate is 45/min. His CT scan head has been reported to show a right-sided small subdural (SDH) with frontoparietal contusions and his chest X-ray is reported to show a small right-sided simple pneumothorax. The next appropriate step in his management would be:
- Give him a IV bolus of 100 mL mannitol
- Start a central line to infuse noradrenaline
- Intubate him immediately
- Do a needle thoracostomy and then proceed for intubation
- Call a neurosurgeon for an urgent evacuation of the SDH
- Ans. dExplanation: Candidates need to know that a simple pneumothorax can be converted into a life-threatening tension pneumothorax once positive pressure ventilation is initiated. To prevent this a needle/finger decompression of the pneumothorax needs to be done before intubation. This should be followed up with an intercostal tube thoracostomy. This is the only situation in primary survey that an intervention in “B” precedes that of “A”.
- The most common cause of shock in trauma is:
- Tension pneumothorax
- Cardiac tamponade
- Neurogenic shock
- Ans. c
- In a trauma victim, which of the following signs is suggestive of a hemorrhagic shock?
- Skin that is warm to touch
- Tachycardia with bounding pulse
- Hypotension with narrow pulse pressure
- Urine output of 1 mL/kg/h
- Serum lactate level <1 mmol/L
- Ans. c
- A 30-year-old motor bike rider, who has met with a high-speed collision, is brought to the ER. On examination, he is confused; peripheries are cold and clammy with a heart rate of 130/min and a blood pressure of 70/60 mm Hg. After placing two peripheral intravenous catheters, 1 L of warmed Ringer's lactate (RL) solution is infused, with no improvement in his hemodynamic or mental status. As the source for a potential bleed is being searched the next most appropriate thing will be:
- Give another 1 liter of warmed RL solution as a bolus
- Give two units of PRBC
- Start an infusion of adrenaline
- Take him to the radiology department for a CT scan of his brain
- Give him an infusion of tranexamic acid 1 g over 8 hours
- Ans. b
- A 35-year-old lumberjack is brought to the ER after having sustained an injury to his left thigh while handling an electric saw. On examination, there is a large gapping incised wound on his left thigh that is spurting blood. Despite direct manual compression and packing the wound, he continues to exsanguinate and starts to drop his blood pressure. The next appropriate step would be:
- To apply a tourniquet to the limb
- To blindly clamp the blood vessels
- To transfer the patient to the operating room for a limb amputation
- Attempting suturing of the wound
- Giving injection tranexamic acid 500 mg intravenous
- Ans. a
- A 25-year-old man who was involved in a motor vehicle crash is brought to the ER by the ambulance crew. Despite having been given 1 liter of warmed normal saline infusion and two units of PRBC transfusion, he continues to be hypotensive with a blood pressure of 70/50 mm Hg and has developed bleeding from his nostrils and oral cavity. While assessing for the source of bleed, the next most appropriate step in his management would be:
- To start an infusion of noradrenaline
- To give an injection of tranexamic acid 500 mg intravenous
- To transfuse another two units of PRBC
- To give an 100 mL intravenous bolus of soda bicarbonate
- To give transfusion of a balanced ratio of PRBC:plasma:platelet concentrate
- Ans. e
- A 65-year-old man has been brought to the ER of a small hospital with no neurosurgical backup after having had a fall off a flight of stairs. On evaluation, he is smelling of alcohol, has pulse rate of 110/min and blood pressure of 120/80 mm Hg. He has a laceration on his forehead, is unresponsive with a GCS of 5, and his pupils are bilaterally equal and reactive. After he has been intubated for airway protection, the next most appropriate step will be:
- Move to the radiology department for a CT scan of the head
- To administer a intravenous bolus of 100 ml of mannitol
- To administer a dose of coma cocktail
- To communicate with the nearest higher center with neurosurgical facility and make arrangements for his transfer
- To start him on an infusion of 3% saline at 25 mL/h
- Ans. d
- Which one of the items in the list given below is NOT an adjunct for primary survey
- Chest X-ray
- X-ray of the pelvis
- CT scan of the head
- Urinary catheter
- Arterial blood gas analysis
- Ans. c
- American College of Surgeons Committee on Trauma. Advanced Trauma Life Support. Student course material, 10th Edition. United States: American College of Surgeons; 2018.
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- Rossaint R, Bouillon B, Cerny V, Coats TJ, Duranteau J, Fernández-Mondéjar E, et al. The European guideline on management of major bleeding and coagulopathy following trauma: fourth edition. Crit Care. 2016;20:100.
- Stiell IG, Wells GA, Vandemheen KL, Clement CM, Lesiuk H, De Maio VJ, et al. The Canadian C-spine rule for radiography in alert and stable trauma patients. JAMA. 2001;286:1841–8.
- World Health Organization. (2006). WHO Generic Essential Emergency Equipment List. [online]. Available from http://www.who.int/surgery/publications/EEEGenericList Formatted%2006.pdf. [Last accessed January, 2020].