1、TRAUMA IN THE PICU,Pediatric Critical Care Medicine Emory University Childrens Healthcare of Atlanta,2,Epidemiology,#1 cause of death in 1yr old Exceeds all other deaths combined 20,000/yr of children & teenagers 65% of all death 19 yrs old unintentional injury 1 death from trauma 40 hospitalized 1,
2、120 treated in ER Most pediatric trauma are blunt injury (vs penetrating in adults) More vulnerable to major abdominal injury from minor forces More immature musculoskeletal system Intra-abdominal organs are proportionally larger & closer together predisposed to multiple organ injury,3,Epidemiology,
3、MVC leading cause of death are unrestrained 2/3 riding with drunk drivers Pedestrian leading cause of death in 5-9 yrs old Bicycle injury increases with age most common is head trauma,4,Physiologic Differences,Larger head greater inertia, movement & transfer of energy to the head & brain Less soft t
4、issue & muscle greater energy transfer to internal organs Difference in center of gravity Infant above umbilicus 1 yr at the umbilicus Adults pubic symphysis Jack knife effect with 2 points restraint spinal and intestinal injury in forward collision,5,Resuscitation,Causes of early death in injury Ai
5、rway compromise Hypovolemic shock CNS injury ATLS : steps in trauma eval Primary survey Adjuncts to primary survey Secondary survey Adjunct to secondary survey (investigations) Definitive managementss,6,Resuscitation Primary Survey,A- Large head/occiput, large oropharyngeal soft tissue, short trache
6、a frequent Right stem intubation 12 yr: needle cricothyroidotomy because cricoid cartilage is the major support structure of airway Surgical tracheostomy 12 yr B Pneumothorax, tension pneumothorax, hemothorax C Normal physiologic status up to 30% loss of total blood vol; traumatic cardiac arrest or
7、penetrating with witnessed arrest poor outcome D Disability: CNS injury E Exposure: prevent further heat loss,7,Resuscitation Secondary Survey,Similar steps as primary survey,8,Resuscitation Investigations,Plain X-rays Lateral C-spine: screen but not adequate in diagnosis Supine chest: pulmonary of
8、mediastinal injuries, not good in diagnosing small pneumothoraces Pelvic: major pelvic disruption Ultra sound FAST: focused abdominal sonography for trauma, not very reliable in children as in adults CT: Chest abd. pelvis as indicated by injury,9,Trauma In PICU,Child abuse & neglect Head injury Spin
9、al cord injury Thoracic injury Abdominal injury,10,Child Abuse & Neglect,Abuse head trauma: most common in PICU causing more long term morbidity Neck is weaker with larger head larger CSF volume (move around), larger water contents increase in deformability More rotational : tear bridging veins (SDH
10、) & axons (DAI) Neurons and axons less protected due to less myelination Skeletal injury: posterior rib fractures, metaphyseal fracture, spinous process fractures,11,Child Abuse & Neglect,Abdominal trauma: 2nd leading cause of fatal injury, 40%-50% death rates Compression: crush solid viscera agains
11、t anterior spine burst injuries to solid viscera & perforation of hollow viscera Deceleration forces shear injuries at the site of fixed, ligamentous attachment with tear & hematoma formation Thermal burns Uniformed thickness closely replicate the objects Abuse scald burns immersion pattern with cir
12、cumferential & uniform depth, well defined edges, spares body creases,12,Severe Traumatic Brain Injury,Statistic230/100,000 3000-4000 deaths/yr; 10-15% are severe with GCS8 deaths or permanent brain damage 0-4 yr: worse outcome probably secondary to non-accidental trauma 5-15 yr: favorable outcome c
13、ompared to adults Goals: to prevent secondary injury Optimize substrate delivery & cerebral metabolism Prevent herniation Target specific mechanisms involved in the evolution of secondary injuries,13,TBI - Pathophysiology,Primary direct disruption of brain parenchyma Secondary cascade of biochemical
14、s, cellular amd molecular events Ischemia/excitotoxicity, energy failure cell deaths Secondary cerebral swelling Axonal injury,14,TBI Secondary Injury,Post-traumatic ischemia Extra cerebral insults hypotension/hypoxemia Early hypoperfusion are common” CBF 20ml/kg/min associated with poor outcome CBF
15、 recovered usually after 24 hrs Delayed in normalization of CBF does not associated with poor outcome,15,TBI Secondary Injury,Excitotoxicity Glutamate other txs- magnesium, glycine site antagonists, hypothermia, pentobarb NMDA antagonists may induce apoptotic neurodegeneration in children,16,TBI Sec
16、ondary Injury,Cerebral swelling: initial min to hrs of post-traumatic hypoperfusion & hypermetabolism metabolic depression (CMRO2 decreases by 1/3 of normal) Edema Vasogenic & BBB disruption Cellular swelling: astrocytes swelling uptake of glutamate,17,TBI ICP Monitoring,Parenchymal fiberoptic & mic
17、rotransducer system Subarachnoid, subdural, epidural- less reliable Ventricular- best monitoring with benefit of draining CSF Keep ICP 60: adolescents lidocaine: decrease catechol surge with direct laryngoscopy,18,TBI Advanced Monitors,Stable Xenon CT CBF monitor regional CBF Stable Xenon technique
18、Transcranial doppler: measured velocity rather than flow, mainly MCA distribution Jugular venous saturation: keep 50%, lower assoc. with mortality NIRS- near infrared spectroscopy: trace the oxidative state of cytochrome, more on trends PO2 microelectrode implantation to frontal parenchyma: also pro
19、vide sign metabolic information: glutamate, lactic acid, glucose, ATP PET: positron emission tomography,19,TBI ICH Management,CSF drain Osmolar therapy Mannitol: Rapid dec. ICP by dec. viscocity dec. bl vessel diameter. Depend on intact viscosity autoregulation. Transient (75 min) Osmotic: (onset 15
20、-30min; duration 1-6 hrs): water moves from parenchyma to circulation; work in intact BBB. May accummulate & worsen cerebral edema Excreted unchanged in urine: may precipitate ATN & renal failure in dehydrated states. OK to use up to osmo of 365,20,TBI ICH Management,Osmolar therapyHypertonic saline
21、: same benefits as mannitol Other benefits: restoration of cell resting membrane potential, stimulation of atrial natriuretic epptide release; inhibition of inflamation; enhance cardiac performance Side effects: extrapontine myelinosis: demyelination of thalamus, basal ganglia rebound ICU Sedation,
22、analgesia, NMB Anticonvulsion: seizures cause inc. cerebral metabolic demands and release of excitatory amino acids Head position 30 degree: dec. ICP & mean carotid pressure with no change in CPP & CBF,21,TBI ICH Management 2nd tier,Barbiturates: dec. ICP via dec. CMR direct neuroprotective effects
23、by inhibiting free radical-mediated lipid peroxidation of membraned Hypervent:dec. post-injury hyperemia & brain acidosis, restore CBF autoregulation Prolonged hypervent: dec. brain interstitial bicarb buffering capacity, gradual dec. local vasoconstrictor effects Hypothermia: 33 C Hyperthermia exac
24、erbates neuronal deaths Decompression craniectomy Lumbar CSF drainage Controlled arterial hypertension,22,Acute Spinal Cord Injury,High cervical injury C1-3 : infants/toddlers MVC, trauma C4-7 : Adolescents/adults sport, MVC Initial injury inc. in inflammatory cells & fibroblasts in cord tissue cell
25、ular necrosis Release of lysosomal enzyme traumatic paralysis “Spinal Shock”: high T or C injuries absence of sympathetic tone hypotension, bradycardia & hypothermia,23,Acute Spinal Cord Injury,Treatment ABC Methylprednisolone 30mg/kg bolus then 5.4 mg/kg/hr for 23 hrs; need to start bolus within 8
26、hrs of injury Careful fluid management with pressors to improve vasodilatation Osomotic diuretic to dec. secondary edema; low molecular weight of dextran to improve microcirculation Hyperbaric oxygen therapy Spinal cord cooling: need to be done within 4 hrs to 10 C How long How to deliver What fluid
27、 Technical difficulty,24,Acute Spinal Cord Injury,Sequelae Respiratory failure: C3-5 innervation of diaphragm; CN IX innvervation to accessory muscle UTI: neurogenic bladder, avoid overdistention and large volume residual, inc. risk of infection Urolithiasis: immobility and hypercalcemia Acute hyper
28、calcemia due to immobility causing vomiting, polydipsia, polyuria, anorexia, nausea, malaise, listlessness,25,Thoracic Injury,2:1 male to female 92%: blunt trauma 48% pulmonary contussion 39% Pneumo/hemothoraces 30% rib fractures 33% in pediatric trauma fatality Airway obstruction Tension pneumothor
29、aces Massive hemothoraces Cardiac tamponade,26,Thoracic Injury,Rib fractures 3 rib fx: reliable indication of intrathoracic or other organ involvements Scapular or post rib fx not associated with great vessels injury Thoracic spine fx inc. suspicion of great vessel injury Pulmonary contussion Absenc
30、e of external signs: chest wall abrasion, tachypnea, abn. BS Tx: fluid management, pulm. Toilet corticosteroid is harmful,27,Thoracic Injury,Pneumo/hemothorax Large bore in hemothorax to avoid fibrothorax Cardiac rupture, pericarcial effusion, cardiac arrhythmias,28,Thoracic Injury,Aortic & great ve
31、ssels injuries Traumatic aortic disruption: mid scapular back pain, UE hypertension, dec. femoral pulses bilaterally, inc. CT output X-Ray: widened mediastinum, deviation of NG or CVL, blurring of aortic knob, abn. paraspinous stripe, right tracheal deviation, upward shift of Left stem main bronchus
32、 Others Diaphragmatic ruptures: LR Esophageal rupture Lung cysts,29,Abdominal Trauma,83% blunt trauma Solid organ injury: liver, spleen, kidneys1- Spleen: extends below costal margin grade I-IV, mainly observation Surgical indication Persistent hypotension or evidence of continuous hemorrhage 50% bl
33、ood volume replacement Other life threatening associated intra-abdominal injury I & II healed after 4 months III-IV: healed after 6-11 months,30,Abdominal Trauma,2- Liver: also extends below the costal margin; associated with highest mortalityMay require surgical correction of injuries to the hepati
34、c vein or vena cava associated with high mortality 3- Duodenum: Mostly hematoma, some with disruption of lumenObservation with TPN, bowel rest, resolution 2-4 weeks 4- Pancreas:- Operative repair depending on anatomy of injury & integrity of the main pancreatic duct- Upper abdominal pain, inc. amyla
35、se, edema of gland, fluid in the lesser sac- Fracture of pancreas when crossing over vertebral colume,31,Abdominal Trauma,6-Small bowel:Disruption, mesenteric avulsion, wall contussionMore at fixation points: proximal jejunum at ligament of Treitz, terminal Ileum 7- Renal trauma:- Flank tenderness,
36、mass or ecchymosis- Hematuria- Hematoma, laceration or vasular injury- Isolated urinary extravasation: not an emergent surg. Expl.- Need Abx- Renal pedicle injuries are rare- Ureteral injury surgical repair,32,Abdominal Trauma,7- Blunt abdominal aortic injury:- Occur in high energy injury- Most comm
37、on at inferior mesenteric artery or at the level of the kidneys- Major abdominal venous injuries are usually fatal,33,Abdominal Trauma,8- Bladder injury: mostly intra-abdominal- Burst injury- Rupture with pelvic fracture- Cystography: extra-peritoneal bladder rupture fluid extending superiorly and a
38、nteriorly to the level of umbilicus - penetrating or bladder neck injury or with vaginal/rectal injury required surgical repair,34,Abdominal Trauma,8- Bladder injury: mostly intra-abdominal- Burst injury- Rupture with pelvic fracture- Cystography: extra-peritoneal bladder rupture fluid extending sup
39、eriorly and anteriorly to the level of umbilicus - penetrating or bladder neck injury or with vaginal/rectal injury required surgical repair,35,Abdominal Trauma,11- Pelvic fracture:- Single fracture of pubic ramus: rarely clinical significance- Multiple fractures: associated with significant intra-abdominal injuries- Sites of silent hemorrhage,
