Severe trauma

Patients with multiple trauma are difficult to manage due to the large number of potential injuries and the initial need to resuscitate the patient while identifying injuries. As emphasized in the chapter on Assessment of the severely ill patient, in the initial stages it is necessary to prioritize tasks, constantly re-assess the priority and repeatedly re-assess the diagnosis as more information becomes available.

The mechanism of injury is particularly important in giving clues to the likely injuries and the likely severity of injury.

Successful management of severe trauma requires teamwork. Team members should concentrate on their allocated tasks while remaining aware of the overall plan and progress. The team leader is responsible for coordinating the efforts of the individual team members and developing an overall management plan.

Initial resuscitation

This is divided into two stages. In the first stage, immediately life threatening injuries and complications are looked for and treated. This is known as the primary survey. The second stage (secondary survey) is carried out once the patient is more stable.

Primary survey

This concentrates on airway, breathing, circulation and neurological injury. Note, however, that neurological injury cannot be reliably assessed until the patient has been resuscitated to normal physiological end-points. Although the assessment of airway, breathing and circulation is described as if it is a sequential process, much of the assessment can and should be carried out simultaneously.

Airway

Patency should be assessed and if necessary restored using the techniques described in Airway management and airway obstruction, modified for the trauma patient. Assume that the trauma patient has a cervical spine fracture and immobilize the neck. The modified jaw thrust (figure 1) is a useful manoeuvre to open the airway without extending the neck.

If airway patency cannot be restored by simple methods, active airway intervention may be needed. The choice of method will depend on the estimated difficulty of orotracheal intubation and skills of the available personnel.

Breathing

Rapid assessment of breathing should be carried out in conjunction with assessment of the airway. Look for signs of increased work of breathing, hypoxia, abnormal chest movement and external signs of chest injury. Measure the respiratory rate in every patient. Palpate, percuss and auscultate the chest. Check for tracheal deviation and look for jugular venous distension suggestive of tension pneumothorax. The three conditions which most often compromise ventilation are tension pneumothorax, open pneumothorax and a large flail segment with pulmonary contusion.

Patients should be given high flow oxygen and the need for mechanical ventilation should be assessed. In addition to respiratory failure, the following are indications for mechanical ventilation:

• Intubation for airway protection
• Severe head injury
• Need for urgent surgery under general anaesthesia

Circulation

Level of consciousness, skin colour and pulse rate give rapidly assessable clues to circulatory status. Loss of consciousness due to blood loss implies that at least half the blood volume has been lost. A pink face and extremities suggest the patient is not critically hypovolaemic while an ashen grey face and white extremities suggest blood loss of at least 30%. Although hypovolaemia is usually associated with tachycardia this doesn’t always occur and hypotension is a late sign of shock.

Table 1 gives a rough guide to estimating blood loss but it should be noted that there may be discordance between clinical signs and that changes in signs are more important than absolute values. Age is an important determinant of the manifestations of hypovolaemia. Young patients tend to compensate well initially but may develop sudden cardiovascular collapse when compensatory mechanisms are exceeded.

Although the usual cause of shock in a trauma patient is hypovolaemia, this is not invariable. If the neck veins are distended, consider tension pneumothorax, concurrent myocardial infarction, cardiac tamponade or myocardial contusion as causes of shock. If there are signs suggestive of a tension pneumothorax this should be treated by needle thoracostomy (figure 2) without waiting for a chest X-ray. A chest drain will need to be inserted later, regardless of whether the needle thoracostomy resulted in release of air.

Fluid resuscitation should be carried out via 2 large IV cannulae in the upper limbs or external jugular veins, initially with warm crystalloid (lactated Ringer’s or Plasma Lyte) solution or colloid. Most severe trauma patients will require transfusion of blood. The severity of hypovolaemia should determine whether this is universal donor blood (rhesus negative group O), unmatched grouped blood or cross-matched blood. The base excess can be used as a guide to degree of shock and adequacy of resuscitation in the first few hours.

The aim of initial resuscitation is not to restore a normal blood pressure. A systolic BP of 80-100 mmHg is probably sufficient in patients who have not suffered a head or spine injury. Resuscitation to higher pressures may dislodge blood clots, cause further dilutional coagulopathy and worsen hypothermia.

It is important to limit bleeding at the same time as starting fluid resuscitation. If there are any signs or symptoms of a possible pelvic fracture, a pelvic binder should be applied, even before imaging is done. If a pelvic binder or a limb tourniquet has been applied in the prehospital phase of care, do not remove these until the patient has been fully assessed (including imaging) and is in an environment where bleeding can be controlled (operating room or angiography suite). Any external bleeding should be controlled by direct pressure. Scalp wounds should be sutured at the earliest opportunity to secure haemostasis. Patients with significant bleeding, who are expected to require massive transfusion should be given tranexamic acid 1 g IV.

Neurological

Consciousness should be assessed using the Glasgow Coma Score after initial resuscitation. Pupil size and reaction to light should be noted.

Investigations

Blood should be taken for arterial/venous blood gases, lactate level, complete blood count, glucose, urea, creatinine, electrolytes, clotting and cross matching. A chest X-ray and pelvic X-ray should be taken early if the patient is unstable. If the patient is stable, a head to pelvis CT scan should be considered at the earliest opportunity.

Secondary survey

This should be carried out after initial resuscitation and treatment of immediately life threatening injuries.

History

The mechanism of injury and the degree of energy transfer gives important clues to likely injuries and their severity. Much of this information can be obtained from police or paramedics. Ask about velocity at impact, direction of impact, damage to passenger compartment of car, height of fall, type of weapon etc.

Table 2 gives the likely injuries caused by motor vehicle accidents based on the mechanism of injury. If the patient was ejected from the vehicle it is not possible to predict the injury pattern. However the patient is at greater risk from virtually all injury mechanisms. With penetrating trauma the type of injury is determined by the region of the body and the speed of the missile.

In addition it is important to try to obtain a history of allergies, drug history, past medical history and any events leading to trauma (eg loss of consciousness leading to motor vehicle accident).

Examination

This involves a thorough head to toe examination which should include examination of the scalp, eyes, maxillofacial region, spine, neck, and perineum as well as more obvious areas such as neurological system, cardiovascular system, chest, abdomen, pelvis and limbs. The patient should be log rolled to examine the back and to perform a rectal examination.

If there is unexplained hypovolaemia, consider the possibility of bleeding from long bone fractures and into the pleural cavities, peritoneal cavity and retroperitoneum.

Additional investigations

These should be based on the history and clinical findings. CT scan stable patients from head to pelvis. Do not take unstable patients to the CT scanner.

Chest injuries

Tension pneumothorax

Characterized by respiratory distress, tachycardia, hypotension, tracheal deviation, unilateral absence of breath sounds, distended neck veins. Cyanosis is a late manifestation. Tension pneumothorax may be confused with cardiac tamponade but tension pneumothorax is more common. Differentiation may be made by unilateral hyper-resonance. Treatment is immediate decompression: insert needle into 2^nd intercostal space in mid-clavicular line (figure 2). The ability to easily aspirate air confirms diagnosis. In the event of failure to aspirate air, withdraw needle but remember the possibility of an iatrogenic pneumothorax now exists. A chest drain should be inserted subsequently.

Spinal injuries

Cervical spine injury can never be excluded on clinical grounds alone in patients with multiple trauma. Assume a cervical spine injury until it has been excluded radiologically. This requires a minimum of a CT with sagittal reconstruction. In some institutions flexion and extension cervical spine X-rays are also required. Note that neurological injury can occur in the absence of bony injury, especially in children.

Hypotension can occur as a result of cervical and high thoracic spinal injuries but spinal shock is an unusual cause of hypotension and is a diagnosis of exclusion.

Until cervical spine injury has been excluded the neck should be immobilized with a hard collar and sandbags (figure 3). If the patient has to be turned he/she should be log-rolled (figure 4a and b).