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Free STEP3 Exam Braindumps (page: 80)

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You are called to the trauma bay to evaluate a 42-year-old male who suffered a blow to his knee at the construction site where he works. He is awake, alert, and his vital signs have been stable in transport. After completing your primary survey, you continue with your secondary survey and determine that his only injury is to his right leg. It is clear that he has suffered a posterior knee dislocation. As part of your examination, you determine that you cannot feel a pulse in his right foot. Realizing that there is compromised blood supply to the patient's right foot, you immediately do which of the following?

  1. Transport the patient to radiology for an arteriogram.
  2. Relocate the knee into anatomical position and re-examine the pulse.
  3. Take the patient directly to the OR to explore his popliteal artery.
  4. Obtain an orthopedics consultation and order films to identify any fractures.
  5. Determine the ankle brachial indices for his right and left foot.

Answer(s): B

Explanation:

It is important to consider vascular injuries in the setting of extremity trauma. This is particularly true in the setting of fractures, dislocations, or penetrating trauma in the vicinity of major vascular structures. When evaluating patients for traumatic vascular injuries, the first step is evaluation of peripheral pulses. This should be done after the initial resuscitation in order to rule out hypovolemia as the source for diminished peripheral perfusion. In the presence of fractures or dislocations, if diminished or absent pulses are identified, it is critical to reduce the fracture or the dislocation and then re-evaluate the perfusion. By placing the bony structures in the anatomical position, you rule out a kink in the vessel as the source of the arterial obstruction. After reduction or relocation, if the pulse is still absent or diminished compared to an uninjured extremity, then further investigation of the vasculature is indicated. In the case described, posterior knee dislocations have a very high incidence of concomitant popliteal artery injury. If vascular compromise is identified after relocation of the knee, operative exploration is indicated for emergent repair of the popliteal artery with a venous interposition graft. It would not be indicated in this setting to delay operative repair for an arteriogram. Arteriograms are indicated in the evaluation of extremity trauma if there are diminished distal pulses after restoring anatomical alignment and the ankle-brachial indices are <0.9.



You are called to the trauma bay to evaluate a 42-year-old male who suffered a blow to his knee at the construction site where he works. He is awake, alert, and his vital signs have been stable in transport. After completing your primary survey, you continue with your secondary survey and determine that his only injury is to his right leg. It is clear that he has suffered a posterior knee dislocation. As part of your examination, you determine that you cannot feel a pulse in his right foot.

Later that night after the patient had been treated and stabilized, you are called to the patient's room to evaluate severe pain in his right lower leg. Upon examining the patient, you determine that he has a bounding pulse in his right foot. However, the patient does state that he has a tingling sensation in his foot and he is in excruciating pain when you flex his foot. Which of the following should be the next step in his treatment?

  1. Increase the dose of intravenous narcotics to help control the pain.
  2. Prescribe an anti-inflammatory drug to enhance the effects of the narcotics.
  3. Order a series of right foot x-rays looking for an occult fracture.
  4. Obtain an emergent arteriogram looking for missed vascular injury.
  5. Emergently take the patient to the OR.

Answer(s): E

Explanation:

It is important to consider vascular injuries in the setting of extremity trauma. This is particularly true in the setting of fractures, dislocations, or penetrating trauma in the vicinity of major vascular structures. When evaluating patients for traumatic vascular injuries, the first step is evaluation of peripheral pulses. This should be done after the initial resuscitation in order to rule out hypovolemia as the source for diminished peripheral perfusion. In the presence of fractures or dislocations, if diminished or absent pulses are identified, it is critical to reduce the fracture or the dislocation and then re-evaluate the perfusion. By placing the bony structures in the anatomical position, you rule out a kink in the vessel as the source of the arterial obstruction. After reduction or relocation, if the pulse is still absent or diminished compared to an uninjured extremity, then further investigation of the vasculature is indicated. In the case described, posterior knee dislocations have a very high incidence of concomitant popliteal artery injury. If vascular compromise is identified after relocation of the knee, operative exploration is indicated for emergent repair of the popliteal artery with a venous interposition graft. It would not be indicated in this setting to delay operative repair for an arteriogram. Arteriograms are indicated in the evaluation of extremity trauma if there are diminished distal pulses after restoring anatomical alignment and the ankle-brachial indices are <0.9.



You are called to the ER to assist with a series of trauma patients who arrived following a multiple vehicle accident. You are assigned to a 22-year-old male who was an unrestrained driver involved in a head-on collision. After you confirm the presence of an adequate airway and equal breath sounds bilaterally, you address his hypotension and tachycardia by giving 2 L of lactated Ringer's solution. His pulse remains elevated at 130 and his blood pressure is 92/55. His pelvic x-ray returns and demonstrates a widening of the pubic symphysis. In addition to continued fluid resuscitation, what is your next step in management?

  1. reduce the pelvic volume with a sheet or pneumatic compression garment
  2. exploratory laparotomy to isolate and control the hemorrhage
  3. CT scan to evaluate for other source of hemorrhage
  4. angiography to embolize pelvic vasculature
  5. obtain additional pelvic x-rays for preoperative planning

Answer(s): A

Explanation:

The x-ray described demonstrates an open book pelvic fracture. This type of injury can often be associated with significant hemorrhage. It is most commonly seen in frontal impacts involving anterior- posterior compression. The majority of the bleeding occurs from the tearing of pelvic veins in the posterior of the pelvis. The initial treatment for open book pelvic fractures is to reduce the pelvic volume to decrease the amount of hemorrhage. In the trauma bay, this can easily be accomplished by wrapping a sheet around the superior iliac crests and twisting the sheet tight using a dowel or by applying the pneumatic compression garment. These are useful techniques in the short term, but definitive treatment will be necessary. This involves formal repair of the pelvis with external fixation or open reduction and internal fixation. If hemorrhage persists despite reduction of the pelvic fracture, pelvic angiography would be the next step in the treatment algorithm to attempt to identify the source of the hemorrhage and embolize the vessel. Given the difficulty of identifying a bleeding vessel in an expanding pelvic hematoma, exploratory laparotomy is not recommended. Finally, an unstable patient should never be transported for imaging studies.



You have been called to the ER to evaluate a 58-year-old female who presented to the hospital for evaluation of a painful left foot. She noticed the pain when she awoke in the morning. She has a history of painful calf muscles when she walks. On your examination, you notice that she has an irregular heart beat, and that she has no palpable pulses and no audible Doppler signals in her left foot. It is cool to the touch and she has some decreased sensation ather toes. Which of the following is the next best step in this patient's management?

  1. an echocardiogram looking for atrial thrombus
  2. initiation of a heparin infusion
  3. duplex imaging of her arterial vessels in her left leg looking for acute occlusion
  4. aortogram with left lower extremity runoff to determine the level of the vascular occlusion
  5. initiate infusion of thrombolytics to dissolve the clot

Answer(s): B

Explanation:

Acute arterial occlusion is a surgical emergency. However, the most important intervention is immediate heparinization. The infusion of heparin will help prevent extension of the clot. Furthermore, it will help to keep collateral vessels open. If the patient is stable enough to undergo operative intervention, a catheter embolectomy would be the procedure of choice. Physical examination findings including vascular examination and level of temperature change and altered sensation can help identify the level of the occlusion prior to operative intervention. Duplex ultrasound is not necessary to isolate the occlusion. Arteriograms are more useful in the OR following the embolectomy. Finally, if small vessel occlusion occurs, catheter-directed thrombolytics can help restore distal perfusion. Once perfusion to the threatened limb has been restored, the workup to identify the thromboembolic source should be obtained. Typical sources for emboli include atrial thrombus, valvular disease, aortic aneurysms, or iliac artery atherosclerotic disease.






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