Emergency Medicine

Explanation

ANSWER: Abrasions over face and torso.

Penny is a paediatric patient in the pre-school age group, which makes her risk of poly-trauma and significant internal injury higher. In simple terms, her smaller size is likely to result in greater energy transfer in high-impact situations and wider transfer of forces to multiple body zones, i.e. combined head, chest, abdomen and pelvic injuries.

Being ejected from a motor vehicle and the presence of fatalities in the same vehicle compartment are highly significant risk and prognostic factors for serious injury.

Explanation

Answer: Airway with Cervical Spine control> Breathing> Circulation with haemorrhage control> Disability or neurological status> Exposure

In trauma, like resuscitation, an ABC approach is adopted for patient assessment and management (Airway, Breathing, Circulation, Disability, Exposure). In the case of trauma however, the mnemonic is modified to:

• Airway with cervical spine protection
• Breathing
• Circulation with haemorrhage control
• Disability and neurological status
• Exposure/Environment

While in reality, assessment of these areas will run in parallel with a large team, rather than in series with one person, it is important to remember this sequence so as to identify the greatest threats to life first

Explanation

Answer: Preventing hypertension

Assessing the adequacy of circulation, looking for evidence of shock: The commonest cause of shock in the context of trauma is hypovolaemic shock secondary to haemorrhage.

Establishing good intravenous access: Necessary to support the circulation with volume and drugs. Looking for evidence of bleeding and controlling haemorrhage: The priorities at C are both to identify any obvious life-threatening injury to the circulatory system so it can be addressed as soon as possible, and to support the circulation where necessary to ensure adequate tissue delivery of oxygen and glucose, thus avoiding secondary injury.

Explanation

Penny is tachycardic, with evidence of poor central and peripheral perfusion. Additionally, Penny is in shock. Though more rigorous definitions of shock exist with strict criteria, a useful working definition of shock is: The failure of the cardiovascular system to maintain tissue perfusion. This is manifest at end-organ level by:

• Tachycardia (Cardiovascular)
• Tachypnoea (Respiratory)
• Reduced conscious level (CNS)
• Decreased urine output (Renal)
• Increased capillary refill time/cool, mottled skin (Reduced skin perfusion)

Some features are more rapidly identifiable than others, such as tachycardia/tachypnoea versus urine output, and some caution must be exercised when interpreting signs of potential shock:

• Conscious level can be impaired by direct injury or by sedation/anaesthetic
• Tachycardia can be a manifestation of pain, fear and anxiety in the paediatric patient
• Tachypnoea may represent primary chest injury but it may also be a response to the shocked state
• We will all demonstrate poor peripheral perfusion if exposed to the elements, such as being trapped in a car crash in winter. This is normal physiology, however, a central capillary refill time of greater than two seconds after pressing for five seconds is suggestive of shock.

Explanation

Answer: Head. You can remember this as "Blood on the floor...and four more" (chest, abdomen, pelvis and long bones):

Head:

A closed head injury is unlikely to accommodate significant blood loss. If a head injured patient demonstrates signs suggestive of hypovolaemic shock, look elsewhere. There are caveats:

• Scalp wounds are extremely vascular and can bleed a lot, particularly in small infants with small circulating blood volumes. This can be significant.
• Neonates don’t have closed heads-their unfused skull bones, vascular scalps and proportionally large heads can expand and accommodate a lot of blood.

Chest:

A large amount of blood can be accommodated in the chest and may be identified at B (assessment of breathing), either by obvious wounds/penetrations, or respiratory signs with distress, reduced air entry and a dull percussion note, and will require cautious drainage.

Abdomen:

A number of solid organs and large vessels in the abdomen are vulnerable either to blunt or penetrating injury and can bleed extensively. At younger ages, the liver, spleen and bladder are more abdominal and less protected by the ribcage and pelvis respectively, with greater risk of injury, including multi-organ injury.

Pelvis:

The pelvis contains a rich vascular supply, with the lower limb arteries and veins passing through it and a large sacral venous plexus. Fractures and shearing forces can cause significant bleeding, which can be contained, or tamponaded, within the closed bony pelvis. If however, pelvic fractures or injuries cause the pelvis to open outward (“open book” injuries), bleeding can continue catastrophically.

Limbs:

Children’s growing bones are very vascular; any open fracture can bleed significantly into the outside world. Certain larger long bones, such as the femur, if fractured and displaced, can accommodate a significant amount of occult blood loss into a potential space.

The scene:

Blood on the floor refers to obvious external haemorrhage, which can be immediately controlled with direct pressure. It is important to remember, however, that a patient may have left their blood behind at the scene. Never assume the paramedic crew will have noticed and told you. Also remember that 50% of every patient is on the other side, so inspect the patient’s back for bleeding or injury, ideally before it drips onto the floor.

Explanation

Answer: C-spine. A significant haemothorax ought to be visible on chest x-ray as whiteout or haziness of the lung field. A fluid level is unlikely as the patient will be supine. Pelvic fractures, particularly an “open book”, are a potential source of life-threatening haemorrhage. Pelvic fractures are often multiple - think of the pelvic ring like a Lifesaver lolly: you can’t break it in just one place.

Explanation

Answer: The correct answer is Crossmatched blood, Type-specific blood or O-negative blood.

Penny has received 40mls/kg of 0.9% sodium chloride, with no response. A child’s circulating blood volume is 60-80mls/kg. She has therefore potentially received 50% of her circulating volume in replacement boluses, with no response in heart rate or blood pressure. This is serious and implies massive haemorrhage somewhere.

By this stage, if not earlier, we would aim to resuscitate with blood and blood products to replace losses like-for-like. The choice of blood depends slightly on the timeframe of need and availability:

• Fully cross-matched blood: Obviously ideal, but can take up to one hour to prepare.
• Type-specific blood: ABO compatible blood, ready in 10-15mins, some risk of lesser antigen transfusion reaction.
• O negative blood: All emergency departments, especially trauma centres, will have immediate access to O negative universal donor blood, often in a blood fridge in the department.

It is important also to remember that clotting factors and platelets are lost or consumed in trauma. Most departments will have a “massive transfusion” protocol to ensure these blood products are given in addition to red cells.

Current thinking, based on battlefield research, is cautious fluid resuscitation (10mls/kg boluses) to a low-acceptable blood pressure, rather than fluid overload, which potentially dislodges evolving clots. The thinking is that “the first clot (at the roadside) is the best clot.”

Explanation

A FAST scan is a focussed ultrasound that can be performed by a trained clinician in minutes.

Views are obtained of four areas (hepatorenal, splenorenal, pelvis/bladder and xiphisternum) to identify the presence or absence of free fluid accumulating in the relevant potential spaces. The assumption is that in the context of trauma, this is blood.

A negative FAST does not rule out bleeding, but a positive FAST effectively rules it in. Caution must be excercised, as FAST will not pick up retroperitoneal bleeds or contained intracapsular hepatosplenic bleeds.

The accompanying two images were obtained as part of a FAST examination (not of Penny). The first shows normal juxtaposition of the liver and kidney without free fluid, while the second reveals free fluid surrounding the liver, as indicated by the arrow.

Reference: UpToDate (www.uptodate.com)

A CT abdomen with double contrast is the gold standard in identifying abdominal or pelvic injuries. However, Penny’s clinical condition makes a trip to the scanner very risky as she is likely to deteriorate in the scanner, often called the 'Donut of Death' with good reason!

There are few indications for a plain abdominal film; this is not one of them.

Explanation

An unstable trauma patient, unresponsive to fluid resuscitation and with a positive FAST scan needs to be transferred to theatre for laparotomy. This can often be a difficult decision to make. However, Penny is unlikely to get any more “stable” without identification and repair of her bleeding. PICU will have nothing to add. Further fluids should continue but not delay transfer and inotropes alone are unlikely to help if the pipes are empty. Penny needs to be transferred to theatre to “stop the tap”.