PAEDIATRIC TRAUMA MODULE

Transcription

1 INTRODUCTION PAEDIATRIC TRAUMA MODULE Trauma is the most common cause of death and disability in children and adolescents. From an ED Trauma perspective, THEY ARE LITTLE ADULTS, with a few nuances. Mechanism varies with age: Motor vehicle accidents most common mechanism across all ages over 1 year of age Pedestrian struck Fall Drowning Burns Push-bike accident Sport related Non-accidental injury (may account for up to 10% of all injury, requires vigilance) General Principals 1 : The sequence of ABCDE remains the same, with nuances Generally children are smaller in size and have smaller body mass, so a large force of impact is potentially applied to a smaller area. Their smaller size means that multiple systems injuries are the more likely Smaller size means head and thorax are more readily involved in pedestrian v car Have a large body surface area to weight ratio - get cold quickly Have pliable bones, forces are more readily transmitted to underlying organs Vital signs vary with age Hypotension is a LATE sign of shock Psychological / developmental considerations difficult to get a history, easily distressed by surroundings. General anaesthesia may be required to allow adequate investigation Family distressed or absent parents (may be injured themselves). Parents may also be effective in keeping the patient calm on initial assessment Size and weight: o Modification to equipment required o Weight based drug and fluid doses Best managed in a paediatric trauma centre, may require transfer once stabilised

2 Useful Equations Based on Weight: Weight: (Age + 4) x 2 up to 10 yo ETT size: (Age/4) + 4 ETT length at the teeth: (Age/2) + 12 Doses: Fentanyl 1-3 mcg / kg Morphine 0.1 mg/kg Midazolam 0.1mg/kg Ketamine 1-2 mg/kg for induction; 0.5 mg / kg for procedural sedation; 0.1 mg/kg for analgesia Propofol 1-2 mg/kg for induction Rocuronium mg/kg for paralysis Suxamethonium mg / kg Fluids ml /kg boluses Blood 10 mg /kg boluses INJURY PATTERNS Head: Larger head, more vulnerable to injury Closed head injury, with increased blood flow; more susceptible to hypoxic insult Impact seizures are common, do not necessarily correlate with radiologically identifiable injury Spine: Paediatric spinal injuries are uncommon, spinal cord injury even less common. Anatomical considerations include relative ligamentous laxity, shallow angulation of facet joints, immature muscles, incomplete ossification of vertebrae and the disproportionately large head with the fulcrum of movement being C2-3 in infants, C3-4 at 6 yo, and C5-6 at 8 yo % of all paediatric spinal injuries are in the c-spine, especially the C1-3 Chest: SCIWORA secondary to pliable bones and ligaments. However, SCIWORA is probably a misnomer due to sensitivity of MRI in detecting radiological abnormality Pliable bones that are less likely to fracture but allow the transmission of force to underlying structures (e.g. pulmonary contusion) increasing the risk of major internal injury with little external evidence of trauma Rib fractures required significant force, so expect associated injuries Most common injuries are pulmonary contusion, rib fractures, pneumothoraces and haemothoraces. Diaphragmatic rupture, aortic disruption, cardiac contusions, tracheobronchial disruption is rare Paediatric patients have a smaller Functional Residual Volume and higher oxygen demand, so will desaturate faster than adult patients

3 Abdomen: Gastroparesis even with minor trauma Swallow lots of air when distressed, which splints the diaphragm, impairing ventilation, and possibly making clinical assessment of the abdomen difficult Large, unprotected intra-abdominal solid organs at risk of injury (rib cage does not extend as far caudally as in adults, the musculature is less well developed and ribs are more compliant) Handlebar injuries duodenal haematoma, pancreatic haematoma / laceration Bladder rupture as intra-abdominal Pelvis: Greater bony compliance and joint elasticity, therefore pelvic fractures suggest major force and increases the likelihood of associated head, chest and intra-abdominal injury Avulsion fractures and single fractures to the pelvic ring are more common in paediatric than adult patients NAI Consider if any of the following: Multiple fractures of varying ages, bilateral fractures Shaken baby - Subdural haematoma, Retinal haemorrhages Peri-orbital injuries Genital injuries Burns Rib fractures Unusual skin bruising patterns i.e. linear bruising on upper arms suggesting of being squeezed, bruises of varying age Injury not consistent with mechanism or age appropriate ASSESSMENT Assessment of paediatric trauma patients should follow the same process as for adults to identify and consequently manage life-threatening issues. There are some anatomical differences when assessing and managing paeds that will be covered in the relevant sections. HISTORY Handover from QAS with particular consideration of mechanism. The mechanism is an important aid when trying to determine possible patterns of injury. Restrained patient Evidence of airway injury Evidence of ventilatory impairment Evidence of circulatory impairment GCS more difficult to determine in children, ask about appropriate crying, interaction, alertness Specific injuries

4 Normal Vital Signs 1 Age Weight kg RR HR SBP (mmhg) Birth 6 months 1 year 2 years 4 years 6 years 8 years 10 years 12 years 14 years EXAMINATION Immediate priority is to identify life threats: AIRWAY Airway obstruction large occiput that may cause neck flexion, requiring padding between shoulder blades to allow for adequate positioning; injuries that may involve / cause airway obstruction Risk of C-spine injury based on mechanism and identified injuries, do not forcefully restrain a child s c-spine, it s best to try to calm the patient using parents, analgesia etc In an intubated patient, confirm tube position and placement (ETTs easily migrate or dislodge in paediatric patients). An intubated right main bronchus may mimic life-threatening chest trauma (i.e. tension pneumothorax, pulmonary contusion, massive haemothorax) BREATHING Ventilatory distress or impending failure Evidence of chest trauma and associated injuries particularly the presence of a tension pneumothorax, rib fractures, pulmonary contusion, massive heamothorax, open pneumothorax CIRCULATION Paediatric patients have increased circulatory reserve, able to tolerate significant blood loss before hypotension occurs. Hypotension is a late sign and is a marker of precipitous deterioration. Bradycardia may also be an indication of imminent arrest Look for markers of poor perfusion / shock tachycardia, reduced pulse volume, cool peripheries, reduced capillary refill, ALOC. Ongoing tachycardia may be a marker of internal bleeding in the absence of evidence of significant external injury Look for blood loss external, chest, pelvis, abdomen, muscle compartments

5 Measure NIBP using an appropriately sized cuff DISABILITY AVPU is easier than GCS in a child. A score of P or U corresponds with a GCS <=8 Assess pupil size and responsiveness Perform gross neurological exam assessing for focal / localising signs suggestive of closed head injury or spinal injury Tense fontanelle suggest intra-cranial injury EXPOSURE Will be at risk of hypothermia if not covered. Exposure is important to look for seat-belt signs, handle-bar injury or other external evidence of trauma, but avoid unnecessary exposure Rectal exam is almost never indicated (exceptions may include suspected spinal injury, compound pelvic fracture) SECONDARY SURVEY Completed once life-threatening issues have been identified and treated, and consists of a detailed head to toe examination, paying particular attention long bones, hands, clavicles, neurovascular status of limbs, spine assessment and a more thorough neurological examination Intra-abdominal injury may be masked by an altered level of consciousness, distracting injury or a patient who is frightened and non-cooperative. Serial examination is important. INVESTIGATIONS Standard baseline trauma bloods will only be indicated in significant mechanisms of injury and they include o Blood gas - will reveal ventilation inadequacy and evidence of hypoperfusion o Note that LFTs and Lipase are not sensitive or specific for liver and pancreatic injury o BSL to exclude hypoglycaemia Urine: Blunt trauma as for adults, frank haematuria indicates an injury anywhere along the renal and genitourinary tract. Microscopic haematuria in the setting of hypotension warrants further investigation as the degree of haematuria does not correspond to the degree of injury. 13 Penetrating trauma - macroscopic haematuria indicates renal or bladder injury 3 ECG is routine in trauma patients, especially patients with chest trauma FAST (Focused Abdominal Sonography for Trauma) can be performed in blunt abdominal injuries to identify haemoperitoneum and pericardial tamponade.

6 FAST is not as well researched in children as adults, although sensitivities have been reported to be approach 100% in the unstable, multiply injured paediatric patient 1. The primary role of FAST is in unstable patients suffering from blunt trauma to direct the team to the abdomen as a source of bleeding, facilitating early laparotomy. However, the role is less certain than for adults as in many situations paediatric patients with free fluid from solid organ injuries are managed conservatively. It is important to note that FAST does not detect hollow viscous injury, most of which mandate laparotomy. Stable patients with concerns for intraabdominal injury (tenderness, guarding, rebound or rigidity) should have a CT. Plain film Trauma Series: CXR Pelvis XR if clinically indicated C-spine Plain Films use clinical judgement and decision rules if required (see below) USS has been supplanted by FAST and the fact that CT has become more readily available. Scan quality is impacted by abdominal distension secondary to gastric stasis / ileus and compliance of the patient with abdominal tenderness. The only real benefit over CT is the lack of radiation, but it has a much lower diagnostic yield compared to CT. CT: Often used in the setting of clinical decision rules in paediatric patients (see below),to minimise exposure to radiation. CT is the examination of choice for: Non-contrast CT head is the modality of choice for suspected closed head injury as quickly identifies injuries that may benefit from neurosurgical involvement (see below for clinical decision rules) Spinal injury (see below) Stable paediatric patients where there is a concern for intra-abdominal injury Chest trauma, especially where the CXR is abnormal or where there is external evidence of chest trauma (seat belt sign). Clinical Decision Rules Clinical decision rules can be used to guide CT imaging for paediatric patients with suspected isolated minor head injury and / or spinal injury. They have no role in decision making for the multi-injured patient requiring CT for other reasons. CT decision rules were derived to reduce the number of un-necessary CT head and spine scans in the paediatric population, reducing radiation exposure and ultimately cost, while minimising the risk of missing clinically important traumatic brain and cervical spine injury. Decision rules are not a substitute for clinical judgment. There are several decision rules available:

7 PECARN (Pediatric Emergency Care Applied Research Network) CT Head Algorithm for Children < 2 (A) and > 2 years old (B) 3 The above algorithm was derived and validated across 25 emergency departments in North America enrolling patients under 18 years of age, of which were younger than 2 years of age. Clinically important traumatic brain injury was defined as death from traumatic brain injury, injury requiring neurosurgical intervention, intubation for > 24 hours due to TBI, hospital admission for more than 2 nights in association with TBI on CT. TBI in 376 children (0.9%) and 60 (0.1%) required neurosurgical intervention. In the < 2 y age group, the rule had a negative predictive value of 100% and a 100% sensitivity for clinically significant TBI. In the > 2 y age group the negative predictive value was 99.95% and sensitivity of 96.8% (did not miss injury requiring neurosurgical intervention). The above algorithm if applied would have led to a reduction of CT scans by 25% in children < 2 y and 20% for children > 2 y. CHALICE CT Head Rule 4 The Children s Head Injury Algorithm for the prediction of important Clinical Events rule (CHALICE) was developed in the UK to be applied specifically to the paediatric population across children presenting with any head injury over 2.5 years. The rule had a 98% sensitivity for predicting clinically significant TBI, and if applied would have led to a CT scanning rate of 14% of the total number of children presenting with a head injury. 1.2% of the study population had an abnormal CT, half requiring neurosurgical intervention.

8 CHALICE rule A CT scan in required in any of the following criteria are present: HISTORY Witnessed LOC > 5 min History of amnesia > 5 min Abnormal drowsiness 3 vomits post injury Suspicion of NAI Seizure of head injury in a patient with no history of epilepsy Examination GCS < 14 or GCS < 15 if under 1 yo Suspicion of penetrating/depressed skull injury or tense fontanelle Signs of BOS # Focal neurology Presence of bruise, swelling or laceration > 5 cm if under 1 yo MECHANISM High speed MVA (pedestrian, cyclist or occupant) Fall > 3 m High-speed head injury from a projectile Assessment of Possible C-Spine Injury in Children Suffering Blunt Trauma The Queensland Paediatric Trauma Service has developed an evidence based pathway for assessing the c-spine of children involved in blunt trauma 5, based on the fact that serious cervical spine injury in blunt trauma is uncommon in the paediatric population (1% of all paediatric blunt trauma cases, incidence ranging from 0.4% in pre-school age to 2.5% in adolescents). The majority of these injuries are stable with only 1-5% requiring operative fixation. Imaging plays an important role in identifying injuries, but has an associated increased life-time risk of malignancy, albeit poorly defined. The PECARN group has identified 8 factors which associated with C-spine injury that form the basis for the clinical algorithm put forward by the Queensland Paediatric Trauma Service:

9 If a patient is having a CT for other injuries, then serious consideration should be given to concurrent CT of the spine. MANAGEMENT Key Issues: A team approach to management occurs in a trauma / resus bay with appropriate nursing and medical staff, equipment and monitoring The goal of management is to treat acute life threats, and facilitate progression towards definitive intervention Psychosocial support for the child allow / facilitate parents to stay in resus room if possible and able to provide adequate support, especially for nonintubated children Family support social work involvement If suspect NAI, there is a legal obligation to report

10 AIRWAY Apply oxygen and titrate to O2 sats >=95% C-spine precautions Basic airway manoeuvres and use of adjuncts as required o Adjuncts Smaller, appropriately sized equipment required. Place guedel without rotating, using a tongue depressor as required Advanced airway as indicated same as for adult: o Impending, potential or actual loss of airway o Ventilatory compromise o Unconsciousness o Agitation requiring sedation or significant ALOC post head injury o Anticipated clinical course o Humane reasons Anatomical considerations that may impact on paediatric airway management: Large occiput that causes passive flexion of c-spine. Paeds patients may require padding under the shoulder blades to allow appropriate positioning Large tongue U-shaped, large and floppy epiglottis that may make visualisation of the cords difficult, requiring a straight (Millers) blade in younger patients (<2) Larynx funnel shaped, more anterior and cephalad making visualisation of the cords potentially more difficult Short trachea increases possibility of right main bronchus intubation, migration of the tube on neck flexion and accidental extubation on neck extension Desaturate quickly due to smaller FRC and high metabolic rate with higher O2 consumption Move towards using cuffed tubes BREATHING Manage associated chest injuries o Tension pneumothorax (needle thoracostomy or simple thoracostomy followed by ICC placement) o Massive haemothorax by ICC placement Note that paediatric patients have a higher respiratory rate, smaller tidal volume, less FRC and higher oxygen demand Intubated paediatric patients should be ventilated at a rate appropriate for their age, and a tidal volume 8-10 ml/kg At risk of barotrauma Early decompression of the stomach via a NGT / OGT will assist in ventilation and should be performed routinely and as soon as possible in intubated children

11 CIRCULATION Control external haemorrhage IV access can be difficult in the paediatric population. Potential sites other than the cubital fossae or back of the hands include the external jugular vein and femoral vein. If peripheral cannulation is unsuccessful after 2 attempts, consideration should be given to rapid IO insertion Permissive hypotension has not gained widespread acceptance at this time. Haemostatic resuscitation along the same lines as for adult patients is gaining more acceptance Warmed 0.9% saline 20ml/kg boluses x 3 then PRBC 10 ml / kg is the standard APLS teaching although in large volume blood loss there is a trend towards minimising crystalloid and initiating blood products earlier. SPECIFIC THERAPY Head: Prevent hypoxia and hypotension and maintenance of cerebral perfusion pressure. Volume load aiming for an age appropriate MAP / SBP, consider inotropes to achieve this after excluding other causes of bleeding, and after a total of 40 ml/kg 0.9% saline If evidence of raised intracranial pressure (e.g. unilateral dilated pupil, bilateral fixed and dilated pupils etc): 5ml / kg 3% hypertonic saline boluses to maintain Na ensure adequate sedation Head-up 30 degrees Loosen ETT ties to ensure venous return from the brain neuromuscular blockade consider cooling (aiming for T o of 34 o C) consider repeat CT head urgent neurosurgical intervention Early post-traumatic seizures (within 7 days of TBI) are common, with 80% occurring in the first 24 hours. Seizures may increase the risk of / exacerbate secondary injury through increasing ICP, metabolic demands and causing hypoxia. Consider seizure prophylaxis (Phenytoin load 20 mg/kg over 30 min - hour) if a structural abnormality is present on CT and in consultation with neurosurgery Spine: Immobilisation may be difficult especially in smaller children / infants. A riskbenefit judgment must be made between keeping small children spinally immobilised to prevent secondary injury vs comfort and distress of the child. Allowing a conscious, cooperative child to find their position of comfort may be more effective in settling the child and allowing assessment. Furthermore, patients who become distressed / agitated with external devices may be at risk of increased instability due to non-anatomical mechanical fixation point 5. Children under 10 who are being kept flat may need a thoracic elevation device to keep alignment of the cervical spine neutral, overcoming a Cobb angle (the difference in the inclination of lines drawn parallel to the inferior end plates of C2 and C6

12 Chest: Minimise IV fluid where possible if pulmonary contusions are present Incidental pneumothorax may be managed conservatively in a non-compromised spontaneously breathing patient, and in a haemodynamically normal ventilated patient who will be closely monitored (i.e. PICU) Massive haemothorax indications for thoracotomy: o Initial drainage exceeding > 15 ml/kg estimated blood volume o Continued bleeding > 1-2 ml/kg/hr Abdomen: Facilitate senior surgical involvement where indicated to assist in decision making regarding management of intra-abdominal injury Selective non-operative management of solid intra-abdominal organs is the norm, with operative management being the exception Hollow viscous injuries are usually explored in theatre, except duodenal haematoma without evidence of perforation, which may be managed conservatively Pelvis: Consider splinting the pelvis in unstable patients with concerns for or actual AP compression fracture Vascular injury is rare in paediatric patients Facilitate orthopaedic involvement in decision making regarding pelvic fractures and IR if evidence of arterial bleeding on CT or the pelvis is the most likely source of blood loss in an unstable patient Isolated pelvic injuries rarely cause haemodynamic instability as they do in adults, consider other injuries in this scenario. Limb fractures / dislocations: Early splinting for analgesia particularly prior to transfers to radiology as reduces pain on transfer Early reduction where required and plaster immobilisation as appropriate o There is enough evidence showing that procedural reduction does not require a patient to be fasted, and that paediatric patients suffer gastroparesis even with minor trauma, making delays to achieve a fasting state inappropriate SUPPORTIVE Analgesia o IV Fentanyl at 1 mcg/kg; morphine at 0.1mg/kg, titrated to effect o Intranasal Fentanyl at 1.5mcg/kg Antiemetic - Ondansetron 0.1 mg/kg Monitor fluid balance and ensure adequate maintenance fluids Monitor temperature Monitor electrolytes

13 DISPOSITION Depends on injuries identified. There is a low threshold to admit paediatric patients exposed to significant mechanism for observation even if no significant injuries have been indentified All children with suspicion of NAI should be admitted to the hospital for safety and further evaluation. A discussion should occur with the local child protection service directly. REFERENCES 1. Cameron et al. Textbook of Emergency Medicine. Churchill Livingstone Cirak B et al. Spinal injuries in children. J Pediatr Surg. 2004; 39(4): Kuppermann N et al. Identification of children at very low risk of clinicallyimportant brain injuries after head trauma: a prospective cohort study. The Lancet 2009; 374: Dunning J et al. Derivation of the children s head injury algorithm for the prediction of important clinical events decision rule for head injury to children. Arch Dis Child 2006; 91: Brady et al. Queensland Children s Hospital, Queensland Paediatric Trauma Service, Assessment of Possible Cervical Spine Injury in Children Suffering Blunt Trauma. Clinical Guideline 2013.