Initial Evaluation of the Pediatric Trauma Patient

INTRODUCTION

Compared to adults, children have anatomic and physiological differences that influence their response to injury, evaluation, and treatment. Blood, fluid, and medication dosing are determined by the weight of the child. Hypotension is unusual in children even with severe volume depletion and, when it does occur, is associated with a worse outcome. Blunt injury more often results in multisystem injury in children than in adults.

UNIQUE CHARACTERISTICS OF CHILDREN

Children have a smaller body mass, less connective tissue, a closer proximity of multiple organs, larger heads, and larger body surface area to mass ratio than adults. As a result, polytrauma is seen more frequently and hypothermia develops more quickly. A child’s skeleton is more pliable and unable to repel external blunt forces, allowing significant internal injury to occur without evidence of external trauma.

EVALUATION

Trauma resuscitation

When encountering an injured child, the priorities are: airway control, ensuring adequate breathing and hemorrhage control.

Most children who survive to receive care will ultimately survive, and those that do not will typically die from loss of airway and/or a traumatic brain injury. Most hemorrhage deaths in children occur immediately after a major vascular injury. It is unusual for a child brought in without signs of life after a blunt injury to survive and, while an initial resuscitation attempt is important, a prolonged attempt including measures such as a resuscitative thoracotomy is inappropriate and may consume precious resources with little hope of success. If signs of life are lost in the resuscitation area, a more aggressive resuscitation attempt may be appropriate for children who achieve a return of spontaneous circulation if an operating room is available, especially following a penetrating injury.

For alert children it may help to have a caregiver, if available, with them during the evaluation and resuscitation. The caregiver can provide important historical information and may comfort and calm the child, allowing a more reliable physical examination.

The primary survey in children is the same as adults, with the following special considerations.

1. Airway
   • Most injured children do not need assistance with their airway.
   • If a child does need assistance, their large occiput may lead to buckling of the posterior pharynx anteriorly and inadvertent flexion of the cervical spine. Placing a 2 cm layer of padding beneath an infant’s torso (and not the head) may improve alignment.
   • The next maneuver to open the airway is to do a chin lift with the left hand shaped as a C, with the 4th and 5^th fingers under the mandible and the thumb and index finger holding pressure onto a mask over the child’s nose and mouth, while the right hand squeezes the ventilation bag. Assess success of ventilation by seeing the chest rise. If successful in providing ventilation, this may be done for several minutes while a physical examination is done, an IV line is inserted and, if available, properly dosed medications and sized equipment necessary for intubation are gathered.
   • If available, using an oral airway makes ventilation easier to sustain. The right size airway is approximately the distance from the patient’s mouth to their ear. To insert the airway, turn it upside down and, while doing a chin lift, insert the airway along the palate over the tongue. Ensure that the airway has gone deep enough along the palate to be past the tongue before flipping it over.
   • Intubating a child is easier than an adult, with some differences. The correct size tube is the width of the child’s little finger and the correct depth of the tube is one that causes both sides of the chest to rise when ventilating, though 3 times the tube size is a good estimate (e.g., 12cm for a 4.0 endotracheal tube). A child’s larynx is more anterior than an adult’s and their tongue larger, so a straight laryngoscope blade is necessary. Placing the blade intentionally too deep, past the larynx, and watching the arytenoids drop into view as the blade is withdrawn is quicker than repeated attempts at moving the tongue. A child’s trachea is short and can often lead to right mainstem bronchial intubation. Once the tube is properly positioned, secure it well, since less movement is needed dislodge the tube in a child. If the patient desaturates, check tube placement and breath sounds to rule out inadvertent extubation or movement down the right mainstem bronchus.
   • In patients less than 12 years, emergency cricothyroidotomy should be avoided, as the cricoid cartilage is more prone to injury, leading to lifelong laryngotracheomalacia. In these patients, when bag-valve and orotracheal ventilation are unsuccessful, needle cricothyroidotomy and jet ventilation with a 16- to 18- gauge needle should be pursued until a definitive tracheostomy can be performed.

• Breathing
  • Most injured children do not need assistance with their breathing and most of those that do also need assistance with their airway, which should be done first. If a child is maintaining their airway and does need help breathing, first provide 6 to 15 liters of oxygen by mask (depending on patient size) if available and examine their chest for chest rise, crepitus and/or decreased breath sounds.
  • Due to their mobile mediastinum, children are more likely to both develop a tension pneumothorax and also show tracheal deviation and bulging jugular veins in response to a tension pneumothorax than an adult. In a child in distress with unilateral decreased chest rise or chest wall crepitus, the first maneuver should be an anterior needle thoracostomy. Place a 14, 16, or 18 gauge IV catheter into the chest in the midclavicular line of the second interspace. Insert the catheter deeply enough to obtain air or blood and advance the plastic catheter while removing the needle. Over time, the catheter may dislodge or kink and should be inspected in the case of later deterioration. For a child not in distress, a chest radiograph should be obtained prior to inserting a needle or tube. If the child survives the initial resuscitation, a chest tube should be placed in children requiring needle decompression. This may be done anteriorly or in the mid axillary line and is similar to the procedure in adults. This is very painful and, if available, local anesthetic and proper IV pain medication should be given first.
  • Monitor oxygen saturation, if available, and keep it greater than 90%.

• Circulation
  • Children tolerate blood loss better than adults. Initial management should focus on hemorrhage control. A tourniquet may be used for actively bleeding extremity injuries, though most extremity bleeding is venous and may be controlled with direct pressure.
  • In general, younger children have higher heart rates and lower blood pressures at baseline (table 1).
  • Early signs of shock in a child are decreased mental status and delayed capillary refill. Hypotension is a late finding. The Shock Index Pediatric Adjusted (SIPA, the highest heart rate divided by the lowest systolic blood pressure) may be helpful to identify early shock. An SIPA value greater than the upper limit may indicate impending shock (table 2).
  • Obtaining IV access in an injured child may be difficult. Peripheral IV access is preferred and a 22 gauge or larger IV is needed to rapidly deliver a large volume of fluid or blood. If a peripheral IV cannot be obtained, intraosseus IV placement into the medial surface of the proximal tibia, approximately 2 cm inferior to the tibial plateau is preferred, if available. If not, cutdown IV placement into the greater saphenous vein anterior to the medial malleolus or the cephalic vein anterior to the medial condyle of the humerus is preferred over central line placement.
  • Provide 20 cc/kg of normal saline or lactated Ringer’s solution as a bolus quickly as possible and reassess. If the patient’s condition has not improved, give a second bolus of 20 cc/kg of fluid and again reassess. If their condition has not improved give 20 cc/kg of blood if available and consider sources of major blood loss. Common reasons for failure to respond are blood loss from intrathoracic or intraabdominal hemorrhage, cardiac tamponade, tension pneumothorax, spinal cord injury above T10 and severe brain injury.
  • A Focused Abdominal Sonography for Trauma examination, if ultrasound is available, may help identify intraperitoneal fluid, pneumothorax, hemothorax and cardiac tamponade in a patient in shock.
  • Endpoints of resuscitation include: urine output of 1-2cc/kg/hr, 2 second or less peripheral capillary refill, normalization of heart rate and blood pressure, and clearing of sensorium.

Table 1. Normal baseline vital signs by age group.

Table 2. Upper limits to normal Shock Index Pediatric Adjusted (SIPA). SIPA is calculated by the highest heart rate divided by the lowest systolic blood pressure.

• Disability
  • The Glasgow Coma Scale is also applicable to children. The verbal score component is modified for children younger than 4 years (table 3).

Table 3. Pediatric verbal score

• Exposure
  • The larger body surface area-to-mass ratio in children as compared to adults may lead to serious heat loss and hypothermia which contributes to metabolic acidosis. Ensure adequate warming with coverage by warmed blankets and using warmed IV fluids if available.

MANAGEMENT OF SPECIFIC PATTERNS OF INJURY

• Head injury

Given their proportionally larger heads, head injuries are common in pediatric trauma. Management of brain injury is focused on preventing secondary brain injury by avoiding hypoxia and hypoperfusion. Early airway control with oxygenation and ventilation, and aggressive treatment of hypotension are vital to avoiding ongoing damage.

• Spinal cord injury

Spine clearance in children is only urgent in children with neurological findings and is typically not an emergency. After an initial cursory examination, spine clearance may be performed after the initial evaluation and resuscitation have been completed, keeping the child’s spine immobilized until then. Alert children may undergo clinical clearance if there is no focal neurological finding, no midline spine tenderness, no abnormal neck rotation or limited range of motion, no neck pain, and if the child is able to focus and cooperate despite other injuries.

Children sustain spinal cord injury without radiographic abnormalities (SCIWORA) more often than adults. Thus, a normal spine x-ray does not exclude significant spinal cord injury in the setting of abnormal neurological examination. Spinal cord injuries in children are treated in the same way as adult brain injuries, with maintenance of oxygenation, ventilation, and perfusion.

• Musculoskeletal trauma

After the airway, breathing and circulation have been addressed, extremities and the pelvis should be assessed for orthopedic injuries. Half or more of pediatric blunt injuries are orthopedic, and, injuries from a blast injury or a projectile, may lead to open fractures and associated with a soft tissue injury.

Evaluation begins with an examination of distal neurovascular function. If neurovascular function is intact, the fracture may be splinted to relieve pain and lessen soft tissue damage, with formal casting awaiting resolution of soft tissue edema. Pediatric fractures heal much more quickly than adult fractures and require less precise approximation than adult fractures to heal. If neurovascular function is not intact, the fracture should be reduced and neurovascular status reassessed. If these have not improved, the child will need exploration of the fracture site in the operating room with possible repair or grafting of a small vessel. Distal humeral fractures are common after a fall onto an outstretched arm, and may result in brachial artery compromise. Reduction and repair of these fractures may be complex, but if the hand is pink and warm, the hand may have sufficient blood flow to remain functional even in absence of a radial pulse.

Open fractures should be treated similarly with prompt administration of IV antibiotics and thorough irrigation and debridement of the soft tissues, with planned reoperations at 24- to 48- hour intervals until the wound is deemed clean enough to close.

Fractures resulting from a crush injury, as would be expected during a building collapse, are associated with a greater incidence of compartment syndrome and may result in rhabdomyolysis if patient extraction is delayed. Identification of compartment syndrome is more difficult in children and its presentation may be delayed a day or more. Tibial fractures, supracondylar humeral fractures and femur fractures are the injuries most commonly associated with compartment syndrome. Younger children may not cooperate with exams or be able to convey their symptoms, but compartment syndrome should be considered in high risk children with the 3 A’s: Anxiety, increasing Agitation, and increasing Analgesic need.

• Blunt abdominal injury

Most blunt abdominal injuries in children do not require an operation. Shock that does not resolve with administration of 40 cc/kg of blood, if available (or a similar volume of IV fluid if blood is not available), peritonitis, and open abdominal injuries do require operation. Hemorrhage control is the goal of laparotomy and complicated intestinal and solid organ repairs may be delayed in unstable patients until a second operation 24 to 72 hours later once the child has undergone additional resuscitation and stabilization.

• Burns

Assessment should include the trauma primary survey with initial resuscitation with LR beginning at 3 mL/kg/% total burn surface area. Give half of that fluid over the first 8 hours and the remainder over the next 16 hours. Children <30kg should receive maintenance fluids of 5% dextrose in lactated ringers in addition to burn resuscitation fluid. Body surface area distribution differs for children, in whom the head represents a larger portion and the lower extremities a smaller portion as compared to adults. The palmar surface of the hand (including fingers) represents approximately 1% of the patient’s body surface. Resuscitation should target 1ml/kg/hr of urine output for flame or scald burns, and 1-1.5 ml/kg/hr of urine output – or until urine clears – for electrical injuries.

• Blast injury

In children who are victims of blast injury, the presence of ‘flash burns’ on their skin or ruptured tympanic membranes indicates close proximity to the blast, increasing the risk of brain injury, pulmonary contusion and bowel injury from the concussive wave. Cluster munitions and improvised devices that contain nails, pellets and other projectiles that cause diffuse, but small and typically shallow penetrating wounds.  Eye injuries are also common and, if visual acuity is normal, may typically be treated with topical antibiotic ointment.

ADDITIONAL CONSIDERATIONS

1. The flexible thoracic cage may allow serious underlying injury (heart, lungs, liver, spleen) without evidence of external trauma or rib fracture. Rib fracture in children less than 8 years of age implies significant impact, which may be associated with significant occult thoracoabdominal trauma.
2. Extremity injuries and scalp or extremity lacerations are frequently missed. Double-check these areas.

SUMMARY

• Children have important differences in anatomy, body surface area, skeletal compliance, and skeletal maturity. Blunt injury results in multisystem injury more often in children than in adults.
  • Children may exhibit few signs of hypovolemia even with severe volume depletion.
  • The larger surface-to-mass ratio in children as compared to adults may lead to serious heat loss and hypothermia, contributing to metabolic acidosis.

REFERENCES

• American College of Surgeons Committee on Trauma. Advanced Trauma Life Support Student Course Manual Chapter 10: Pediatric Trauma. 2018.

• Woo R, Albanese C. Surgery: Basic Science and Clinical Evidence. Chapter 36. Pediatric Surgery. 2nd ed. Springer Science; 2008.