Trauma Board Review Part I

1. Trauma Board ReviewPart I Tiffany Truong, MD, MPH October 3, 2007

2. A 94-year-old woman is sent from a local nursing home after falling from her wheelchair. Her transfer note asks you to “rule-out subdural.” You know that: A. Blood collects in the subdural space more quickly than in an epidural hematoma. B. Infants and toddlers rarely develop subdural hematomas. C. Most subdural hematomas are due to penetrating head injury. D. The risk of developing a subdural hematoma decreases with age. E. The usual mechanism is a sudden acceleration-deceleration of brain parenchyma and tearing of bridging veins.

3. Answer E • Subdural hematomas (SDH) are caused by sudden acceleration- deceleration of brain parenchyma with subsequent tearing of the bridging veins. Brains with extensive atrophy, such as the elderly and alcoholics, are more susceptible. Children under the age of two are also at increased risk. Blood tends to collect more slowly than epidural hematomas because of its venous origin.

4. Subdural Hematoma • Bridging veins between dura and ararchnoid • Presentation • Decreased mental status and LOC • May have lucid period • Classification • Acute <24 hours (hyperdense=white on CT) • Subacute = 24 hours – 2 weeks (isodense) • Chronic > 2 weeks • Six times more common than epidural • Higher mortality rate than epidurals • Elderly, alcoholics are at increased risk • CT scan: crescent-shaped lesion

5. Subdural Hematoma

6. Epidural hematoma • Usually arterial bleed (middle meningeal artery) between skull and dura • “Coup” • Underlying brain injury usually not severe • Presentation • LOC -> then Lucid interval • Skull fracture lac MMA • Dilated ipsilateral pupil and contralateral hemiparesis – late findings • CT: biconcave or lenticular

7. Epidural hematoma

8. The most common CT scan abnormality found after severe closed head injury is: A. cerebral contusion. B. epidural hematoma. C. intracerebral hemorrhage. D. subdural hematoma. E. traumatic subarachnoid hemorrhage.

9. Answer E • Traumatic subarachnoid hemorrhage – • Blood within the CSF, caused by disruption of subarachnoid vessels. • Most common CT finding in mod/severe TBI • Associated with a worse prognosis in these patients.

10. You have just received by ambulance a comatose19-year-old college student with severe midface fractures following a collision with a lamppost. Medics were unsuccessful in field intubation, so you prepare to do rapid sequence intubation, knowing that: A. Thiopental can raise both systemic and intracerebral blood pressure. B. Etomidate is contraindicated. C. Ketamine reduces intracerebral pressure, but may cause severe laryngospasm. D. Pretreatment with lidocaine is not indicated. E. Succinylcholine should be avoided unless a defasciculating dose of a nondepolarizing agent has first been given.

11. Answer E • Lidocaine effectively attenuates the cough reflex, hypertensive response, and increased ICP associated with intubation. • Thiopental may also be effective but should not be used in hypotensive patients. • If succinylcholine is used, premedication with a subparalytic dose of a nondepolarizing agent should be considered if time permits, since fasciculations produced by succinylcholine may increase ICP. • Etomidate has beneficial effects on ICP by reducing cerebral blood flow and metabolism. • Ketamine should be avoided because it increases ICP.

12. A 19-year-old man was assaulted and robbed outside the baseball stadium after “bat day.” He has an obvious mid-face fracture and unstable mandible. His left eye is mildly proptotic with severe conjunctival swelling and a subconjunctival hemorrhage. Visual acuity is limited to counting fingers. His pupil is fixed and mid-point. You must now: A. arrange for stat consult with ophthalmologist. B. avoid sedation and analgesia, so as not to mask intracranial injuries. C. obtain intraocular pressures. D. apply a firm occlusive eye patch and arrange outpatient follow-up. E. perform emergent lateral canthotomy.

13. Answer E • If a patient with orbital emphysema complains of a sudden decrease in visual acuity in the traumatized eye, air may have built up under pressure in the orbit, causing cessation of blood flow in the central retinal artery. Immediate release of this pressure is necessary if the patient’s vision in that eye is to be saved. Performing a lateral canthotomy with cantholysis or an intraorbital needle aspiration of the trapped air may release the pressure. Accumulation of blood in the retro-orbital space may similarly threaten vision and is treated by lateral canthotomy.

14. Head Injury Pearls • Cushing reflex: in response to rapid incr in ICP, hypertension + brady • Isolated linear nondepressed skull fx: no treatment • Basilar skull fx: temporal bone, hemotympanum, CSF otorrhea/rhinorrhea, periorbital ecchymosis, retriauricular ecchymosis • Diffuse axonal injury is the most common brain injury resulting in coma. • TBI: mild (GCS>14), mod (9-13), severe (<8)

16. A 6 yo male was the rear-seated passenger in a moderate-speed MV crash. He reported that his “legs were numb” immediately following the collision, but within 30 min these symptoms resolved. His exam was entirely normal, and his plain radiographs were normal. Which of the following is correct: A. Regardless of his normal exam and radiographs, he requires urgent MRI. B. He can safely be discharged with close fu as long as his exam remains normal during a 4-hr observation. C. Flexion-extension radiographs should be performed to rule out any ligamentous injury. D. CT scan of the C-spine should be performed to assess for surrounding soft tissue swelling.

17. Answer A • Spinal cord injury without radiographic abnormality (SCIWORA) can present in children with even minor trauma. Increased flexion of the spine and spinal column in pediatric pts can permit spinal cord injury without fx or dislocation. • MRI should be performed and neurosurg should be consulted for any pediatric pt with neuro complaints following trauma, even if complaints are transient. • Admission for observation is generally mandated. Flex-ext radiographs and CT do not exclude diagnosis of SCIWORA.

18. A 60-yo alcoholic female was BIBEMS with c/o weakness. The patient’s friends found her “passed out” at the bottom of the the stairs this morning. They put her in bed, but she still c/o weakness. On PE, she has 4+ reflexes throughout, 3/5 UE strength b/l, 4/5 LE muscle strength. What is her most likely diagnosis: A. Subdural hematoma B. Anterior cord syndrome C. Central cord syndrome D. Cauda equina

19. Answer C • Central Cord Syndrome • Fall with hyperextension injury • Weaker in upper extremities compared to lower extremities • Brown Sequard syndrome • Hemisection of spinal cord, due to penetrating trauma • Loss of ipsilateral motor, position, vibration • Contralateral loss of pain and temp below level of injury

20. Spinal Cord Injuries (cont) • Anterior Cord Syndrome • Flexion of cervical spine • Bilateral paralysis of arms and legs equally • Due to arterial occlusion, disruption blood flow to spinal cord • Cauda Equina • Distal sacral roots- peripheral nerve injury • Variable motor/sensory loss in LE, sciatica, bowel/bladder dysfunction, saddle anesthesia

21. Spinal Cord Injuries (cont) • Spinal Shock • Partial or complete injury • Areflexia, loss of sensation, flaccid paralysis below level of lesion • Flaccid bladder and loss of rectal tone • Bradycardia and hypotension

22. A 16-month-old child is brought to the emergency department immobilized in cervical spine precautions. The child was an unrestrained passenger in a moderate-speed rapid-deceleration motor vehicle collision. You are concerned about possible neck injury, keeping in mind that: A. Pseudosubluxation of C3 on C4 is common in children. B. The small neck muscles make fractures more common than ligamentous injury. C. The predental space should not exceed 4 to 5 mm in children younger than 10. D. Anatomic features of the cervical spine approach adult patterns at around 12 years of age. E. If the child was ambulatory at the scene, spinal precautions are unnecessary

23. Answer C • Pseudosubluxation of C2 on C3 - occurs in approximately 40% of children up to adolescence. Anatomic features of the cervical spine approach adult patterns between the ages of 8 and 10 years. • On a lateral cervical spine view the distance between the anterior aspect of the odontoid process and the posterior aspect of the anterior ring of C1, the so-called predental space, should not exceed 5 mm in a child. • Compared to adults, the child has relatively underdeveloped neck musculature and a head that is disproportionately large and heavy compared to the body, leading to fewer fractures and more ligamentous injuries.

24. A 16 yo high school football player is brought in by ambulance after experiencing beck pain when he “speared” another player with his helmet. Paramedics had immobilized his neck on scene. He is neurologically intact. Which cervical spine injury is most likely? A. Bilateral facet dislocation B. Hangman fracture C. Jefferson fracture D. Odontoid fracture E. Teardrop fracture

25. Answer C • Jefferson fx – • axial loading forces • Burst fx of C1 • Unnstable • Hangman fx • Hyperextension, knot of noose placed anteriorly • Located in pedicles of C2, with C2 displacing anteriorly on C3 • Unstable • Today most common – head on MVA • Associated with prevertebral swelling and cause respiratory obstruction

26. Cervical Spine Fractures (cont) • Odontoid fx – most common is type II • Teardrop fx • Extreme flexion • Complete disruption of all ligamentous structures at the level of injury • Unstable

27. 32 yo man p/w stabbed in the L side of his neck with a pocket knife. Injury if inferior to angle of mandible, superior to cricoid cartilage, post of sternocleidomastroid. Depth of wound unclear, but penetrates platysma. There is no bleeding from wound and no evidence of tracheal deviation or JVD. PE: no carotid bruits, no stridor, no SQ emphysema, strong carotid pulses b/l, nl neuro exam. Other than pain to wound area, pt is asymptomatic. VS: BP 128/82, HR 86, R 16, O2sat 99% RA. Which of the following about the pt is correct? A. Can be discharged home after neg local wound exploration. B. Injury mandates an esophagram and esophagoscopy C. Injury mandates laryngoscopy and bronchoscopy D. Injury mandates local wound exploration in the ED E. Observation alone is appropriate.

28. Answer B

29. Penetrating Neck Injury • Any wound which violates platysma • Injuries-most occur in Zone II • Vascular > CNS • Peripheral nerve > brachial plexus • Vascular injuries require proximal and distal control • Death=CNS, exsanguination, airway compromise (intubate early)

30. Penetrating Neck Injury

31. Penetrating Neck Injury • Hard signs + unstable -> surgical exploration in OR • Stable patients • Zone I: angiogram, esophagram/endoscopy, bronchoscopy • Zone III: angiography • Zone II: exploration or triple study (angio + esophgram + bronchoscopy)

33. Blunt Neck trauma • Rare due to protection of head, shoulders and chest • Mechanism: steering wheel, dashboard, shoulder belt shearing forces, clothes line injuries • Laryngotracheal and pharyngoesophageal injuries can be subtle require diagnostic imaging • Carotid artery injury: pseudoaneurysm or dissection • Mechanism: hyperextension, hyperflexion, direct blow, intra-oral trauma, basilar skull fracture • Neurologic symptoms may be delayed

35. What is the most commonly injured organ of the genitourinary tract? A. Urethra B. Kidney C. Bladder D. Ureter

36. Answer B • Kidney - the most commonly injured organ of the GU system • Contusions (92%), followed by lacerations, renal pedicle injuries, and renal ruptures or shattered kidneys. • Bladder – 2nd most commonly injured • Assoc with blunt trauma and pelvic fx. • Urethral injuries – freqly in men, assoc with pelvic fx • Ureter – rarest • most likely caused by penetrating trauma

37. A 23-yo man was the unrestrained driver in a MVA. On PE, blood is noted at the urethral meatus, and there is perineal ecchymosis. Which of the following is the next management step? A. Insertion of a coude catheter B. IV pyelogram C. Pelvic CT scan D. Retrograde urethrogram E. Urinalysis with sample obtained by suprapubic route.

38. Answer D • Urethral injury: suspected if • Blood at the urethral meatus • Perineal ecchymosis • Blood in the scrotum • High-riding or nonpalpable prostate • Pelvic fracture • Transurethral cath contraindicated • Evaluated by retrograde urethogram • Only if urethral integrity compromised should placement of suprapubic cath be considered • IV pyelogram – eval kidney and ureter injuries

40. A 25 yo man arrives in the ED reporting a GSW to the R arm approx 15 min PTA. Which of the following findings on PE suggest the presence of an arterial injury requiring expeditious angiography or surgical intervention? A. Diminished distal pulses B. Injury to an anatomically related nerve C. Unexplained hypotension D. Proximity of the injury to major vascular structures

41. Answer A

42. Arterial Injury: Penetrating Extremity Trauma

43. Arterial Injury: Penetrating Extremity Trauma • Hard signs: expeditious angiography and/or surgical intervention • Soft signs: inpatient admission for observation and repeat exams • No hard or soft: Observe in ED 3-12 hrs, discharge home with close fu. • No signs of arterial bleed • No bone or nerve injury • No developing compartment syndrome • Minimal soft tissue defect

45. A 22 yo woman who is 28 weeks pregnant presents after falling down 3 stairs and landing on her right side. She denies abdominal pain, contractions, and vaginal bleeding. Her PE is unremarkable other than a small contusion to her right flank. Which of the following is the appropriate management? A. Discharge home with approp precautions and 24-hr follow up. B. External tocodynamics monitoring for 4 hrs C. US followed by external tocodynamics monitoring for 24 hrs D. US with discharge home if negative

46. Answer B • Pt is at risk for Placental Abruption although her trauma appears minor. • Major prospective study showed that minimal of 4 hrs of external tocodynamic monitoring was able to predict immediate adverse pregnancy outcome: • < 3 contractions her hour – discharge • 3-7 C/H: monitor 24 hours • > 8 contractions: higher risk of placental abruption, none occurred in patients < 8 C/H • US is not sensative to exclude placental abruption.

47. Which of the following is an indication for emergency department cesarean delivery after maternal trauma? A. Absence of fetal heart tones B. Fundal height at 19 cm C. GSW to uterus with vaginal bleeding D. Maternal death after 5 minutes of profound shock and a 26-week fetus. E. Solitary GSW to head with stable vitals signs of the mother.

48. Answer D • Indications for Perimortem C-section: • Fetus viable – cardiac activity on US • Gestational age > 23 weeks • Survival from postmortem cesarean delivery unlikely 15 mins after maternal death. • No specific duration of death beyond which C section is contraindicated. • GSW to uterus or solitary GSW to head with stable VS are not indication for emergency ED C section.

49. A 19 yo man is BIBEMS. He was the unrestrained driver in a single-car crash and was ejected from the vehicle after it hit a tree. He is amnestic to the event, and there is odor of alcohol on his breath. His main complaints are chest and abdominal pain. VS: BP 78/48, HR 122, R 16, T 37.5. Neck veins are flat. What is the most likely cause of his hypotension? A. Cardiac tamponade B. Cardiogenic shock C. Hypovolemia D. Spinal Shock E. Tension PTX

50. Answer C • Hemorrhagic shock presumed in any hypotensive trauma pt until proven otherwise. • Spinal Shock – bradycardic, hypotension • Cardiogenic shock (presumed 2 myocardial contusion) – distended neck veins • Hypotension due to decrease venous return • Tension PTX - distended neck veins, tracheal deviation, tachypnea, decrease BS on side of PTX • Cardiac tamponade - distended neck veins unless pt has profound hypovolemia