Trauma II Board Review

1. Trauma II Board Review Tiffany Truong, MD, MPH Mount Sinai School of Medicine December 5, 2007

2. A 50 yo M presents after a MVA with bruising over his sternum. He states that he hit his chest against the steering wheel. His VS are unremarkable, and he is asymptomatic except for anterior chest wall tenderness at the site of bruising. The init CXR and sternal view reveal a sternal fx but are otherwise nl. There are no other assoc injuries. EKG is nl. Which of the following is the MOST appropriate management plan for this pt? A. Admit for 24 hr telemetry monitoring. B. Perform 2 sets of CE and TPN tests, and dc if neg. C. Perform echocardiogram in the ED, and dc if neg. D. After a repeat EKG in 6 hrs, dc the pt with pain medication, without any further testing.

3. ANSWER: D A. Admit for 24 hr telemetry monitoring. An isolated sternal fx is no longer considered an indicator of significant blunt myocardial injury and does not mandate a work up for BMI. B. Perform 2 sets of CE and TPN tests, and dc if neg. CK lacks specificity. Tpn may be elevated in pts with BMI, but their elevation doesn’t predict clinically significant complications, and they should not be used as screening tests in the ED. C. Perform echocardiogram in the ED, and dc if neg. Echo is not useful as a screening test for detecting clinically significant BMI. D. After a repeat EKG in 6 hrs, dc the pt with pain medication, without any further testing.

4. Blunt Myocardial Injury (aka Myocardial Contusion) • Clinical features: pt in MVA > 35 MPH c/o chest pain • Significant BMI unlikely, ~3% develop dysrythymia, 70% have tachycardia out of proportion to blood loss, conduction defect • CXR greatest value for finding assoc injuries: pulmonary contusion, rib fx. Sternal fx no longer considered impt. • Initial EKG predictive of subsequent clinically significant EKG events – recommend initial EKG followed by repeat EKG in 4-6 hrs. • Common ekg abnormalities are PVCs, 1st degree av block, RBBB (Right ventricle is closest to anterior chest wall)

5. A 35 yo M presents with a single stab wound to R lateral chest. He has no other injuries. His VS are blood pressure 150/80 and HR 100. His breath sounds are clear and equal b/l. Which of the following is the BEST management plan for this patient? A. Obtain a CXR, and discharge pt if negative. B. Obtain a CXR on presentation, and perform a second one in 6 hrs. Discharge pt if both are neg. C. Obtain a CXR on presentation, and perform a second one in 12 hrs. Discharge pt if both are neg. D. Discharge home, and instruct the pt to return if he develops shortness of breath.

6. ANSWER: B A. Obtain a CXR, and discharge pt if negative. A PTX may be delayed after a stab wound, 12% of pts will require chest tube for delayed hemothorax or pneumothorax. B. Obtain a CXR on presentation, and perform a second one in 6 hrs. Discharge pt if both are neg. C. Obtain a CXR on presentation, and perform a second one in 12 hrs. Discharge pt if both are neg. Most of PTX will be evident on CXR performed at 6 hours. D. Discharge home, and instruct the pt to return if he develops shortness of breath.

7. Which of the following statements regarding blunt thoracic aortic rupture is correct? A. External evidence of chest trauma is often lacking. B. Fractures of the 1st and 2nd ribs are highly suggestive of aortic injury. C. Most common symptom is dysphagia. D. Most tears occur at the ascending aorta. E. Obscuration of the aortic knob is the most sensitive sign on CXR.

8. ANSWER: A A. External evidence of chest trauma is often lacking. Fewer than 50% have external signs of trauma. B. Fractures of the 1st and 2nd ribs are highly suggestive of aortic injury. Not associated with increased risk. C. Most common symptom is dysphagia. Most common sx interscapular or retrosternal pain, absent in up to ¾ of pts. D. Most tears occur at the ascending aorta. Descending aorta. E. Obscuration of the aortic knob is the most sensitive sign on CXR. Widening of mediastinum.

9. Thoracic Aortic Disruption • Rapid deceleration injuries. • Most common cause of death in blunt trauma, 80% die at scene, 10-20% die w/in 1st hour. • Signs & sx: include chest pain, back pain, dyspnea, intrascapular murmur, and extremity pain caused by ischemia. • CXR: widen mediastinum (8 cm) most common. Nl in 2–7% of patients with aortic injury. • Angiography gold standard, but now CT. • Tx: BP management and surgical repair.

10. 76 yo F unrestrained driver in MVA p/w respiratory distress on arrival and has paradoxical movement of her R chest during labored respirations. BP 138/76, HR 118, RR 28, O2sat 88% RA. BS auscultated on both sides of chest. ABG on high flow O2: pH 7.37, Po2 78, HCO3 28. Which of the following is correct? A. Can be treated with supplemental oxygen and admission to stepdown unit. B. Injury mandates early ventilatory support. C. Most likely cause of hypoxia is splinting fr pain D. R chest wall moves outward with inspiration and inward with expiration. E. Tx involves analgesia and adhesive tap or rib belt to stabilize chest.

11. ANSWER: B A. Can be treated with supplemental oxygen and admission to stepdown unit. High potential for deterioration. Early ventilatory support and ICU. B. Injury mandates early ventilatory support. C. Most likely cause of hypoxia is splinting from pain. Pulmonary contusion. D. R chest wall moves outward with inspiration and inward with expiration. Inward with inspiration and outward with expiration. E. Tx involves analgesia and adhesive tap or rib belt to stabilize chest. Inhibit expansion of chest and aggravate atelectasis, worsening gas exchange.

12. Flail Chest • Segmental fractures in 2 or more locations on the same rib • Paradoxical inward movement of the chest wall during inspiration and outward movement during expiration • Significant blunt trauma (MVA, fall from height) • Initially compensate for reduce TV by hyperventilate, when fatigue or underlying pulmonary injury develops -> respiratory failure. • Tx: Supplemental oxygen is the first-line treatment. Pain control with analgesia to allow pt to fully expand lungs and improve ventilation. Early intubation considered. • External chest wall support reduce VC, worsen respiratory function, no indicated. • Indications for early vent support: shock, three or more associated injuries, severe head injury, comorbid pulmonary disease, fracture of eight or more ribs, or age greater than 65 years

13. Which of the following is the BEST method for diagnosing a diaphragmatic injury in a patient with a stab wound to the left upper quadrant? A. Computed tomography. B. Diagnostic peritoneal lavage. C. Upper gastrointestinal series. D. Laparoscopy.

14. ANSWER: D A. CT. CT may miss small diaphragmatic injuries from penetrating trauma. B. DPL. The threshold RBC count for a positive lavage should be lowered since diaphagmatic injury does not result in as much bleeding as with solid organ injury. C. Upper GI series. Upper GI series may demonstrate displacement of viscera into chest after blunt diaphragmatic injury, but this does not occur acutely after penetrating trauma due to the small size of the hole. D. Laparoscopy. With penetrating trauma, the diagnosis of diaphragmatic injury is difficult and may only be made with laparotomy or laparoscopy.

15. Diaphragmatic Injuries • Majority caused by penetrating trauma. • Occur predominately on L side b/c liver protects right side. Most likely sight of injury posterio-lateral portion of L diaphragm • Often difficult to visualize on initial chest x-ray (nasogastric tube may enhance diagnosis). Abdominal viscera or NG tube seen in thoracic cavity • CT scan or laparoscopy more sensitive, although diaphragmatic ruptures can be missed even on initial CT. • Delays in diagnosis lead to increased morbidity and mortality.

16. A 27 yo M p/w a single stab wound to L flank. VS are BP 110/80, HR 90. Which of the following is the most appropriate next step in management? A. DPL B. Wound exploration with a cotton swab. C. CT with IV contrast. D. CT with oral, rectal, and IV contrast.

17. ANSWER: D A. DPL. In a pt who is hemodynamically stable after penetrating flank trauma, DPL would be helpful for intraperitoneal injury but does not sample the retroperitoneal injury (kidney). B. Wound exploration with a cotton swab. Difficult and limited, esp with deeper wounds that extends to muscle layer. C. CT with IV contrast. D. CT with oral, rectal, and IV contrast. Triple contrast should be used to identify rectal and sigmoid injury. Oral contrast may not extend down to these areas. Accuracy of CT for flank stab wounds approaches 98%.

18. Flank or Back Wound • Associated with to retroperitoneal injuries such as the colon, kidney, ureters and major vascular structures • Colon is the injury most often missed. If colon injury is suspected, serial physical examination is extended to 72 hours, watching for fever or a rise in WBC • An alternative is to perform a triple-contrast CT scan. Where the wound track extends up to the colon, or there is evidence of abnormal bowel wall thickening, laparotomy is indicated.

19. An 8 yo M hit a car door while riding his bike. Upon presentation, he is crying and c/o abdominal pain. His PE reveals age-appropriate vital signs, an abrasion across his epigastrium, and diffuse tenderness w/o rebound or guarding. Labs are notable for amylase 220 Iu. UA reveals 2-5 RBCs per HPF. Which of the following is correct? A. Despite a nl abd CT, the child could have pancreatic injury and should be admitted for observation. B. An IV pyelogram should be performed for evaluation of hematuria. C. The bowel is the most commonly injured organ following this mechanism. D. Duodenal hematoma is unlikely if a repeat exam reveals no abdominal tenderness.

20. ANSWER: A A. Despite a nl abd CT, the child could have pancreatic injury and should be admitted for observation. B. An IV pyelogram should be performed for evaluation of hematuria. In pts with nl VS and microscopic hematuria, no further wu is indicated as long as pt is asymptomatic. C. The bowel is the most commonly injured organ following this mechanism. Spleen, followed by liver, are most commonly injured organs, with bowel injury occuring < 5% of pts with blunt abd trauma. D. Duodenal hematoma is unlikely if a repeat exam reveals no abdominal tenderness. Duodenal hematomas can be missed by both PE and CT. A contrast-CT can aid in diagnosis, but if this injury is suspected based on mechanism of injury, the child should be admitted for further eval and observation.

21. Traumatic Pancreatitis • Clinical: mild epigastric tenderness, resolve in early stages of injury, then increased severity w/I 6 hrs when pancreatic enzymes begin irritating the peritoneum, which may become superinfected and produce retroperitoneal abscess. • CT scan can’t exclude blunt pancreatic, diaphragmatic, or bowel injury. • Serum amylase is normal in up to 37% of pts with pancreatic injury • Rapid deceleration or severe crush injury

22. A 52 yo back seat passenger presents after being involved in a high speed MVA. Inspection of the abdomen reveals the findings c/w lap belt injury. Compared to other patients with blunt abdominal trauma, this patient is at increased risk for injury to which of the following organs? A. intestine B. kidney C. liver D. pancreas E. spleen

23. ANSWER: A A. intestine. When lap belt bruises are present, there is a higher incidence of intestinal injury. Although seat belt sign is seen in only 1/3 of cases, its presence is highly correlated with injury. Diaphragmatic injury can been seen secondary to compressive forces. B. kidney C. liver D. pancreas E. spleen

24. Seat Belt Sign • Low-lying transverse abdominal ecchymosis has a strong association with hollow viscus injury and mesenteric tears . • Hollow viscus injury often does not produce any pain or tenderness until 6-8 hours following the traumatic event. • At minimum, patients with lap-belt contusions should undergo serial abdominal examinations. • Findings of abdominal tenderness should prompt diagnostic study (e.g., abdominal CT and/or DPL) or laparotomy.

25. Which of the following statements regarding lightening injuries is correct? A. Aggressive fluid loading is indicated. B. Fetal death is common in pregnant victims. C. Lower extremity paralysis is rare. D. Rhabdomyolysis is a frequent complication. E. Tympanic membranes usually are normal.

26. ANSWER: B A. Aggressive fluid loading is indicated. Overly aggressive fluid admin may worsen cerebral edema. B. Fetal death is common in pregnant victims. (50% fetal mortality rate). C. Lower extremity paralysis is rare. 2/3 p/w LE paralysis and 1/3 with UE paralysis. D. Rhabdomyolysis is a frequent complication. Rhabdomyolysis occurs in only 6% of pts. E. Tympanic membranes usually are normal. More than 50% of lightening injury victims have perforated TMs.

27. Lightening • Electrical and most lightning burns have an entrance and exit point • Death usually secondary to cardiac arrest, lightening causes massive countershock and produces asystole. • Burns are superficial, deep muscle damage rare. • Cataracts are common and may occur immediately or develop up to 2 yrs after incident. • Secondary injuries: ruptured TMs, spinal fractures at multiple levels, bilateral scapular fractures, internal organ injuries, long-bone fractures, intracranial bleeding, seizures, cardiac arrhythmias, and cardiac arrest.

28. In approximately what percentage of patients is laparotomy required for an anterior abdominal wall stab wound? A. 10%. B. 30%. C. 50%. D. 70%. E. 90%

29. ANSWER: B A. 10%. B. 30%. C. 50%. D. 70%. E. 90%

30. Anterior Abdominal Stab Wounds • 2/3 pts have peritoneal violation, of these ½ (30% of those injured) will require laparatomy. • General rule of thumb: 1/3 don’t penetrate peritoneum, 1/3 penetrate but don’t require laparotomy, 1/3 require laparotomy. • Local wound exploration followed by • Discharge home if no violation anterior fascia • Admission for observation/serial PE/DPL if superficial muscle fascia violated. • Indications for exploration: progressive abdominal tenderness, increasing leukocytosis, fever, abdominal distension, etc.

31. 75 yo F slips and falls in her bathtub and injures her L hip. She is helped out of the bathrub by her daughter but is unable to ambulate secondary to pain. In the ED, initial hip and pelvis xrays are neg. The pt continues to have pain in her L leg when she attempts to ambulate. What is the next most appropriate management? A. Admit to a rehab facility for physical therapy B. Order inlet and outlet views of the pelvis C. Order MRI of the left hip D. Order nuclear bone scan E. Prescribe narcotic pain meds and a walker and arrange for outpatient orthopedic evaluation.

32. ANSWER: C A. Admit to a rehab facility for physical therapy. Underlying occult fx would be worsen with early mobilization. B. Order inlet and outlet views of the pelvis. Unlikely to diag occult fem neck fx. C. Order MRI of the left hip D. Order nuclear bone scan. Useful but more sensitive after 72 hours. E. Prescribe narcotic pain meds and a walker and arrange for outpatient orthopedic evaluation. Underlying occult fx would be worsen with early mobilization.

33. Occult Femoral Neck Fracture • Suspect in elderly pt when hip pain prevents ambulation but plain films don’t reveal a fracture. • MRI within 24 hours on injury often reveals a fx that was imperceptible at time of injury. • Senile osteoporosis leading cause of femoral neck fx with minor trauma.

34. Which of the following statements regarding blunt traumatic placental abruption is correct? A. In pregnant women with blunt trauma, less than 40% of fetal losses result from placental abruption. B. More than ½ of women with placental abruption can present with no vaginal bleeding. C. Position of the placenta affects the incidence of traumatic placental abruption. D. Ultrasonography is the best method for identifying placental abruption. E. Women with traumatic placental abruption are less likely to have coagulopathy than are those w/o traumatic placental abruption.

35. ANSWER: A. In pregnant women with blunt trauma, less than 40% of fetal losses result from placental abruption. Leading cause of fetal loss aside from maternal death in TPA. B. More than ½ of women with placental abruption can present with no vaginal bleeding. C. Position of the placenta affects the incidence of traumatic placental abruption. Does not affect. D. Ultrasonography is the best method for identifying placental abruption. Fetal distress most sensitive for TPA, measured by cardiotocographic monitoring. E. Women with traumatic placental abruption are less likely to have coagulopathy than are those w/o traumatic placental abruption. Women w/ TPA 54 x more likely to have DIC.

36. Traumatic Placental Abruption • In blunt trauma, shearing and deceleration forces separate placenta from uterine wall. • Disrupts gas exchange b/ fetus and mother -> hypoxia -> fetal distress. • In blunt trauma, 50-70% fetal loss result fr placental abuption. • Classic: vaginal bleeding, abd pain, amniotic fluid leaking, fetal distress; 63% women may not have vaginal bleeding. • Diag: Cardiotoco monitoring.

37. A 20 yo F presents for evaluation of a sprained ankle. She sustained the injury while running, despite pain, she was able to talk for a short distance and is able to walk 4 steps in the ED. Radiographs are not indicated if the exam also reveals absence of bony tenderness: A. About the anterior talotibial joint B. Along the posterior edge of the distal 3cm and the tips of both malloeli and tibial plafond. C. Along the posterior edge of the distal 6 cm and of the tips of both malleoli D. Over the deltoid and anterior talofibular ligaments E. Over the distal tibia laterally & prox fibula.

38. ANSWER: C A. About the anterior talotibial joint B. Along the posterior edge of the distal 3cm and the tips of both malloeli and and tibial plafond. C. Along the posterior edge of the distal 6 cm and of the tips of both malleoli D. Over the deltoid and anterior talofibular ligaments E. Over the distal tibia laterally & prox fibula.

39. Ottowa Ankle Rules: • Ankle radiographs are required if either of the following is present: • Patient is unable to bear weight and walk 4 steps immediately after the injury and at the time of evaluation. • Or there is tenderness along the posterior edge of the distal 6 cm of the tips of either malleolus. If patient does not meet either of these criteria, radiographs are not necessary. Rules does not apply to subacute/chronic injuries or patients with multiple injuries, intoxication, or altered sensation, neurologic injuries, or head injuries.

40. Which of the following is the most common mechanism of injury associated with isolated blunt pancreatic injury in children? A. Direct blow to the abdomen from a pitched baseball. B. Fall from a 2nd-story window onto a hard surface C. Handlebar injury during neighborhood bicycle accident D. Lap-belt injury during a high-speed motor vehicle crash E. Straddle injury from a fall onto a rigid horizontal pole.

41. ANSWER: C A. Direct blow to the abdomen from a pitched baseball. Commotio cordis. B. Fall from a 2nd-story window onto a hard surface. Other solid organs more likely from wide distribution of forces. C. Handlebar injury during neighborhood bicycle accident D. Lap-belt injury during a high-speed motor vehicle crash. Bowel injury and lumbar spine injury. E. Straddle injury from a fall onto a rigid horizontal pole. Genitourinary injuries.

42. Commotio Cordis • Sudden cardiac death or near sudden cardiac death after blunt, low-impact chest wall trauma in the absence of structural cardiac abnormality • Ventricular fibrillation is the most commonly reported arrhythmia induced • Young male athletes aged 5–18 years • Blows to the chest from baseballs, softballs, hockey pucks, and other objects. • Death is usually instantaneous, and successful resuscitation is uncommon.

43. A 62 yo M presents after being struck in the head with a piece of lumbar 2 hours earlier. His wife says that he was “dazed” immediately after the accident but did not lose conciousness. He says he has a headache. GCS 15. PE is normal except for 3 cm scalp hematoma. The next appropriate next step in management is: A. Admit to ED observation unit for serial neurologic exam. B. Discharge with head injury instructions. C. Obtain a noncontrast CT head and neurosurgery consult. D. Obtain a noncontrast CT head and if negative, discharge. E. Obtain skull x-rays to screen for more severe intracranial injury.

44. ANSWER: D A. Admit to ED observation unit for serial neurologic exam. B. Discharge with head injury instructions. C. Obtain a noncontrast CT head and neurosurgery consult. D. Obtain a noncontrast CT head and if negative, discharge. E. Obtain skull x-rays to screen for more severe intracranial injury.

45. ACEP Clinical Policy for mild TBI Definition: At least one met: 1) Any of loss of consciousness (LOC) of less than 30 minutes and GCS score of 13 to 15 after this period of LOC; (2) any loss of memory of the event immediately before or after the accident, with posttraumatic amnesia of less than 24 hours; (3) any alteration in mental state at the time of the accident (eg, feeling dazed, disoriented, or confused). “Is there role for plain film skull xrays in assessment of acute mild TBI in the ED?” No, the literature does not support the use of skull xrays in the ED. (level B recommendation)

46. ACEP Clinical Policy for mild TBI “Which patients with acute MTBI should have a noncontrast head CT scan in the ED?” A head CT scan is not indicated in those patients with MTBI unless one of the following is present: headache, vomiting, age greater than 60 years, drug or alcohol intoxication, deficits in short-term memory, physical evidence of trauma above the clavicle, or seizure. (level A)

47. ACEP Clinical Policy for mild TBI “Can a patient with mild TBI be safely discharge from the ED if the head CT shows no acute injury?” Pt can be discharged under the following conditions: (level C) Pt presents at least 6 hrs after injury Clinical exam is normal Head CT shows no acute abnormality Pt under supervision of a responsible 3rd party can be discharged sooner than 6 hrs

48. The End!