ACUTE TRAUMA LIFE SUPPORT (ATLS)
A regulated and planned approach to the seriously injured trauma patient is presented, using the ATLS guidelines.
PRIMARY SURVEY AND RESUSCITATION
A. Airway and Cervical Spine
The airway may be:
● patent, partially obstructed, or completely obstructed (this may result from physical obstruction or loss of muscle tone)
● adequately protected or at risk
Check for responsiveness
Is the patient alert and responsive to questions? A verbal reply confirms that there is:
¤ a maintained and protected airway
¤ temporary adequate breathing and circulation
¤ cerebral functioning
Look listen and feel for breathing
The absence of breath sounds indicates the need to attempt airway opening manoeuvres, and if unsuccessful to consider the possibility of airway obstruction.
Look for signs of partial upper airway obstruction
¤ Snoring - the familiarsound of obstruction caused by the soft tissuesof the mouth and pharynx. It often accompanies the reduced muscle tone of a lowered level of consciousness.
¤ Rattling or gurgling - the soundof fluids in the upperairway.
¤ Stridor - a harsh crowing sound best heard on inspiration. Stridor suggests obstruction at the levelof the larynx and uppertrachea.
¤ Drooling - the inabilityto swallow saliva.It suggests blockageat the back of the throat.
¤ Hoarseness - gross voice change. This also suggestsobstruction at the level of the larynx.
Management
The possibility of an injury of the cervical spine should be suspected in all patients with a significant history of trauma. In these cases no airway manoeuvres should involve movement of the neck. Immediate manual cervical spine immobilisation should be done by a designated team member until the primary survey has been completed and an immobilizing device can be applied.
A rigid cervical collar can be applied to assist with spinal immobilisation but it should not delay the management of the airway. The cervical collar alone does not provide complete stabilisation of the cervical spine.
The stepped airway protocol is followed if any signs of a compromised airway are present. The aim is to open and improve, and then to establish and secure.
¤ The mouth is opened and the oral cavity inspected (chin lift / jaw thrust manoeuvre). Any visible foreign objects must be removed (finger sweep, Magill's forceps). If any secretions or blood are present, rapid controlled suctioning with a rigid suctioning tip is performed under direct vision.
¤ This is followed by placement of an oropharyngeal tube, if a gag reflex is absent. This is a temporary measure, while the intubation equipment is prepared.
¤ Endotracheal intubation :
This is the gold standard for definitive airway management.
An assistant should apply in line cervical spine immobilisation, preferably from the caudal position.
Pre-oxygenation with 100% oxygen is performed for 2-3 minutes. Cricoid pressure is applied during manual ventilation.
A pulse oximeter is used to monitor the patient.
The time of intubation should not be longer than 30 seconds, the time of an average breath hold.
It is important to replace the oropharyngeal tube in the mouth after endotracheal intubation to prevent the patient from biting the tube.
The position of the tube should always be checked personally, by auscultation, first over the epigastrium, then over the axillae.
¤ A surgicalairway may be necessary if endotracheal intubation fails.
Oxygen.
All trauma patients must receive the highest possible oxygen concentration.
Risk of aspiration
All trauma patients should be presumed to have a full stomach. This, together with alcohol intoxication, increases the risk of vomiting and subsequent aspiration. It takes only one breath after vomiting to aspirate.
A rigid suctioning catheter should be at hand and the patient turned to the left lateral position if signs of vomiting appear. If this cannot be done safely and immediately, the head of the bed should be dropped 20 degrees and the vomit is suctioned from the mouth.
A. Breathing
This part of the examination should be done in a careful and systematic way, otherwise important information will be missed.
Inspection
¤ Rate, rhythm, depth, symmetry of breathing
¤ Loss of consciousness
¤ Colour - cyanosis
¤ Trachea - displaced
¤ | Neck veins | - distension in tension pneumothorax/cardiac tamponade |
¤ | Swelling around the neck | - haematoma, surgical emphysema |
¤ | Accessory muscles | - platysma, scaleni, intercostal, abdominal |
¤ | Chest wall | - wounds, recession, airway obstruction, paradoxical movement, flail chest |
¤ | Abdomen | - abdominal breathing, spinal injury between level C5 and T12, gastric distension splinting diaphragmatic movement. |
Palpation ¤ Symmetry of movement | - unequal, flail chest, pneumo/haemothorax | |
¤ | Tenderness | - rib fracture, flail chest |
¤ | Crepitus | - displaced fractures |
¤ | Surgical emphysema | - chest and neck |
Percussion | ||
¤ | Dull | - haemothorax |
¤ | Resonant | - normal or pneumothorax |
¤ | Hyper-resonant | - tension pneumothorax |
Auscultation | ||
¤ | Air entry | - always compare left with right (axillae more accurate than anterior chest because of less muscle and fewer transmitted sounds from large airways) |
¤ | Breath sounds | - crepitations, rhonchi, wheezes, transmitted upper airway sounds |
¤ Re-confirm placement of endotrachealtube
Factors which compromise breathing
¤ Central depression
¤ Airway obstruction
¤ Tension pneumothorax (diagnosis must be made clinically!): respiratory distress, tachycardia, distended neck veins, hyper- resonance and absent ipsilateral breath sounds, contralateral tracheal deviation, hypotension, pulsus paradoxus.
¤ Open chestwound - suckingwound especially if > 2/3 of trachealdiameter, preferential flow throughwound
¤ Flail chest - two or more ribs fracturedat two or more places
¤ Massive haemothorax - hypotension, decreased breath sounds, dullness to percussion
¤ Cardiac tamponade- hypotension, muffledheart sounds, tachycardia, pulsus paradoxus, distended neck veins (not visible if hypovolaemic)
A pulse oximeter is a useful guide during the assessment of breathing but it does not give a direct reflection of the partial pressure of oxygen in the blood : 100% oxygen saturation = PaO2 > 90 mm Hg, 95% = 70 mm Hg, 90% = 60 mm Hg.
Management
Detailed discussion of management will be discussed later in the module, only a brief outline will be presented here.
1. Airway obstruction - reassess airway
2. Apnoea or bradypnoea - rescue breathingshould be instituted and definitive airway established.
3. Tension pneumothorax - treatment should not be delayed in order to confirm with chest x-ray. Immediately decompress with a 14 gauge cannula in the second intercostal space, midclavicular line.
4. Sucking chest wounds - should be immediately sealed off with an occlusive dressing on three sides, allowing air to escape from the pleural cavity (one way valve) in order to prevent a tension pneumothorax caused by air leakingfrom the underlying injured lung.
5. Flail chest - may be associated with significant underlying lung contusion and progressive hypoxia. The treatment is aimed at correcting the abnormality in chest movement and optimally ventilating the damaged lung tissue through intubation and positive pressure ventilation.
6. Cardiac tamponade - immediate needle pericardiocentesis can be attempted. Beware of false negativeaspiration due to clotted blood. Urgent thoracotomy if required. Fluid resuscitation provides only temporaryimprovement.
7. Massive haemothorax - this is confirmed (during the secondary survey) by placementof an intercostal drainage tube and drainageof
>1500 ml blood initially or >200 ml/hour. The placement of an intercostal tube does not resolve the emergency, but should be followed by an emergency thoracotomy. These patients are ideal candidates for autotransfusion. A massive haemothorax may not be obvious on a supine chest x-ray owing to blood spreading posterior to the lung.
B. Circulation and Haemorrhage Control
The presence of a carotid pulse should be checked for 5-10 seconds. The rate, rhythm and symmetry must be noted. The presence of tachycardia is one of the most sensitive indicators of early circulatory shock.
The location of the most peripheral pulse is a useful guide to the systolic blood pressure.
¤ radial pulse: systolic bloodpressure (SPB) at least 80 mm Hg
¤ femoral pulse : SBP at least 70 mm Hg
¤ carotid pulse : SBP at least 60 mm Hg The presence of external bleeding is determined Signs of circulatory shock to be lookedfor:
¤ loss of consciousness
¤ respiratory rate : tachypnoea
¤ neck veins: distended - cardiac tamponade, tension pneumothorax
The following 4 signs are all indicative of peripheral vasoconstriction, one of the first compensatory mechanisms during circulatory shock.
Colour : central or peripheral pallor or cyanosis
Moisture : diaphoresis Temperature : cool Capillary refill : > 2 seconds
An ECG monitor and blood pressure recordings assist in the assessment of the above signs. Always treat the patient and not the monitor!
Blood loss can be expressed as a percentage of blood volume according to the following :
< 15 %
15-30%
30-40%
>40%
For possible sources of blood loss (one on the floor and four more)
¤ | On the floor | - history from paramedics |
¤ | In the chest | - heart, great vessels or lung laceration: > 2 litres blood; - ribs: 100 to 200 ml each |
¤ | In the abdomen | - aorta, inferior vena cava, liver or splenic injury : 2 litres |
¤ | In the pelvis | - pelvic fracture: 1 - 3 litres. |
¤ | In the thigh | - femur fracture: 1 - 2 litres |
- other long bones: 0.5 - 1 litres
Management
● Control external haemorrhage:
¤ Direct pressure
¤ Elevation
¤ Pressure points (radial, brachial, femoral etc)
¤ Mast suit of limitedvalue in terminating arterial haemorrhage (inflated pressure 30-40 mm Hg)
● Establish 2 large bore IV lines
14/16 cannula with high capacity administration set
Compare: 14G - 125ml/min = 1 litre over 10 minutes 18G - 35 ml/min = 1 litre over 30 minutes
Peripheral lines are the first option with the least complications. Limbs with proximal long bone fractures must be excluded.
In adults there are 3 alternatives if a peripheral site is not available or attempted unsuccessfully. Venous cut-down requires the correct equip- ment and can be time consuming if the practitioner is not experienced. Central venous pressure lines carry an increased risk of complications and require more experience. The addition of a pneumo or haemothorax
may further compromise the already traumatised patient. A large short bore cannula, which will allow faster infusion rates, should be used.
Femoral lines are of limited value for the purpose of drug administration during severe hypovolaemia or active resuscitation where there is minimal blood flow below the diaphragm. Femoral lines should also be used with caution when the inferior vena cava and iliac vessels may be compromised as a result of abdominal or pelvic injuries.
In children less than 6 years of age there is one alternative if a peripheral site is not available or unsuccessful, namely an intra-osseus line. The maximum flow rate is 40-50 ml/min through an intra-osseus needle.
Proximal long bone fractures must be excluded.
Obtain blood samples for biochemistry, full blood count/haematocrit and cross match. Pregnancy testing must also be considered in a female patient of childbearing age.
● How much fluid?
The traditional concept of "as much as possible as soon as possible" has fallen into disfavour. Hypotensive resuscitation (SBP - 90-100 mmHg) is becoming more popular owing to the fact that it decreases the gradient for blood loss and reduces the "blowing off" of clots from damaged blood vessels. Massive infusion of clear fluids will increase bleeding, cause haemodilution and disseminated intravascular coagulation (DIC). It can also cause hypothermia if not warmed to 40 degrees C.
Fluid resuscitation has only limited value and should not delay surgical consultation and subsequent operative management to locate and terminate haemorrhage.
If the patient is hypotensive, 1 litre crystalloid (Ringers, 0.9% saline) may be infused and the patient's response evaluated. If there is no response, another litre is infused while ordering O type blood. If there is no response after the second litre, colloids (starches, gelatines) may be considered until the blood arrives. If there is a transient response to the fluid therapy, there may be time to order type specific blood.
Dextrose containing solutions have no place during fluid resuscitation. Less than 100 ml of each litre remains intravascular! Increased serum glucose concentrations may actually cause osmotic diuresis.
Hyperglycaemia may aggravate head injuries.
Adrenaline and other resuscitation drugs have very little place in hypovolaemic shock.
C. Disability and Neurological Evaluation
A brief neurological evaluation is performed and any evidence of neurological deficit or lateralising signs should be noted.
AVPU or Glasgow Coma Scale Score
The above are used in the assessment of level of consciousness. A patient with spinal injuries might not respond to pain stimuli owing to the absence of sensation at that level.
A | = | Alert |
V | = | Responds to verbal stimuli |
P | = | Responds to painful stimuli |
U | = | Unresponsive |
Pupillary size, equality and reaction
A unilateral dilated pupil indicates a focal intracranial mass lesion and necessitates urgent referral to a neurosurgeon.
D. Exposure and Environmental Control
The patient's clothes should be cut to provide exposure to enable further clinical examination to take place. Prevention of hypothermia is very important.
E. Resuscitation
Re evaluate :
a) Airway
b) Breathing/Ventilation/Oxygenation
c) Circulation
d) Urinary and Naso-gastric catheter
e) Monitoring:
¤ Ventilatory rate, arterial blood gases and end tidal CO2
¤ Pulse oximetry
¤ Blood pressure
¤ ECG
f) Xrays - chest, cervical spine and pelvis
g) Consider need for transfer
SECONDARY SURVEY
The secondary survey only commences after the primary survey has been completed and the resuscitation is well under way. It is a rapid but thorough physical examination for the purpose of identifying as many injuries as possible. However, it is important to note that if the patient's condition deteriorates, one must revert to the primary survey (ABC). The secondary survey should not delay definitive care.
Objectives of the secondary survey
● Reassessment of vital signs
● Detailed head to toe examination
● Complete medical examination
● Special investigations
● Assimilation of all the clinical, laboratory and radiological information
● Formulation of a management plan for the patient
● Clinical records for medicolegal purposes
a) History : (AMPLE)
● Allergies
● Medications
● Past History
● Last meal
● Events
● Blunt trauma
¤ Penetrating injury
¤ Burns or cold injury
¤ Hazardous environment
b) Physical examination
● Head
● Maxillofacial
● Cervical spine and neck
● Chest
● Abdomen
● Perineum/Rectum/Vagina
● Musculoskeletal
● Neurological
c) Re-evaluation
d) Definitive Care
e) Three important Xrays
1.) Chest Radiography
Good radiographic technique is essential for producing good diagnostic chest Xrays.
¤ Exposure factors
Looking through the heart on a PA film one should just be able to make out the architecture of the thoracic vertebrae. If these are seen too clearly, the film is over-penetrated, if not seen at all the film is under-penetrated, making it difficult to comment on the lungfields.
¤ Size and shape of the chest- exposures will vary according to the size and shape of the chest.
¤ Good inspiration - one should be able to visualize at least 11 ribs posteriorly above the diaphragm. Poor inspiration will result in difficulties in measuring heart size and assessing the lungs.
¤ Patient positioning - PA position is best. AP films will result in difficulties in assessing cardiac size and pulmonary vasculature. Check that patient is not rotated by checking that the medial edges of the clavicles and the spine are equidistant.
How to read a chest radiograph
1. Soft tissues : compare both sides. In females check for both breast shadows. Look for signs of surgical emphysema.
2. Skeleton: count all ribs and check for fractures. Check clavicles, scapulae, shoulders, thoracicand cervical spines.
3. Pleura. Check costophrenic angles for haemothorax. Check for pnemothorax.
4. Diaphragm : the righthemidiaphragm is 2cm superior to the left. Compare the shape and position. Look for free air under the diaphragm.
5. Mediastinum: check the position of the heart with two thirds of the transverse diameter of the heart to the left of the spine and one third to the right. In the superior mediastinum the trachea should be central. Check for widening of the superior mediastinum at the level of the aortic arch.
Heart size is <50% off transthoracic diameter.
6. Hilar region : the left is 2cm superior to the right. Check position, contour and density.
7. Lungs : compare both sides. Divide the lungs into three zones: upper, middle and lower and compare both sides.
A few important points:
On a supine AP chest Xray a haemothorax may be difficult to detect as there may only be a white haze present on the affected side. When in doubt request a lateral decubitus xray. Similarly a pneumothorax may also be difficult to detect, this is best seen in erect films taken in expiration.
A subpulmonic haemothorax may appear as a raised diaphragm on the affected side, if in doubt request a lateral decubitus CXR.
2) Cervical Spine Xrays
The lateral cervical spine radiograph taken after spinal trauma is the single most useful projection. All seven cervical vertebrae should be included.
Special projections such as the swimmer's view should be performed if the C7/T 1 junction cannot be visualized.
The 5 spinal lines to be assessed are as follows :
Line 1 : Pre-vertebral soft tissue line.
Anterior to the upper four cervical vertebrae, the maximum pre- vertebral soft tissue width is 5mm, while in the lower cervical spine
the soft tissue width should not exceed the AP diameter of the adjacent vertebral body.
Line 2 : Anterior spinal line
This line links the anterior cortices of the cervical vertebral bodies, and should form a gently curving line.
Line 3 : Posterior spinal line
This links the posterior cortices of the cervical vertebral bodies, and should form a gently curving line.
Line 4 : Spinolaminar line
The line links the junctions between the laminae and base of the spinous processes of the cervical vertebrae. It should form a gently curving line.
Line 5 : The spinous processes should be examined for the presence of fractures.
3) Pelvic Fractures
These can be broadly classified into stable and unstable fractures.
1. Stable fractures :
a) do not involve the pelvic ring e.g. avulsion fractures, isolated fractures of the iliac wing
b) involve the ring but result in little bone displacement, leaving the soft tissues intact.
2. Unstable fractures :
Generally involve the pelvic ring in two or more sites. Look carefully at the posterior sacroiliac joints for possible displacement, indicating instability. These fractures are often associated with severe visceral and major vessel damage.
SUMMARY
The ABC system of managing the resuscitation of the severelyinjured patient during the first few minutes to one hour of arrival offers a safe, efficient initial approach to the trauma patient. The flow of the process identifies the potentially lethal injuries first and takes steps to reverse them as they are discovered. Management of a condition is possible without a firm diagnosis, it may not be known what the cause of the problem is, but there must be clarity about what to do about it.
The first priority is to evaluate the patient rapidly and to detect and treat all immediately life threatening conditions.
Following this, a detailedhead to toe assessment can be completed. The team leaders can then list the patient's injuries and establish priorities for both further investigation and definitive treatment.
An adequate history of the patient and the incident is as essential as the clinical examination in evaluating and managing the trauma patient.
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