A 66-year-old man presents to the emergency department for a 1-hour history of right arm weakness. He was having breakfast this morning when his right arm suddenly became weak, causing him to drop his coffee mug. He also noticed that he was slurring his speech and had some additional weakness in his right leg. He had no symptoms prior to the onset of the weakness and noted no other unusual phenomena. These symptoms lasted for about 30 minutes, but they resolved completely by the time he arrived at the emergency department. His medical history is notable for hypertension and hyperlipidemia, but he does not receive close follow-up from a primary care physician for these conditions. The patient currently is not taking any medications. His pulse is 75/min, the blood pressure is 160/95 mm Hg, and the respiratory rate is 14/min. Physical exam is remarkable for a high-pitched sound heard on auscultation of the neck, the remainder of the exam, including a complete neurological exam, is entirely unremarkable. CT angiography of the head and neck shows no active hemorrhage and 80% stenosis of the left internal carotid artery. Which of the following is the next best step in the long-term management of this patient?
Q172
Paramedics are called to a 35-year-old man who had accidentally amputated his left index finger tip with a knife. He has no significant past medical history. His temperature is 37.2°C (99°F), pulse is 96/min, and blood pressure is 112/72 mm Hg. Pulse oximetry on room air shows an oxygen saturation of 99%. His left index finger is amputated distal to the distal interphalangeal joint at the level of the nail bed, and exposed bone is visible. There is profuse bleeding from the wound site. His ability to flex, extend, abduct, and adduct the joints is preserved and sensation is intact. The remainder of the examination shows no abnormalities. Which of the following is the most appropriate next step prior to transporting this patient to the emergency department?
Q173
A 23-year-old male presents to his primary care physician after an injury during a rugby game. The patient states that he was tackled and ever since then has had pain in his knee. The patient has tried NSAIDs and ice to no avail. The patient has no past medical history and is currently taking a multivitamin, fish oil, and a whey protein supplement. On physical exam you note a knee that is heavily bruised. It is painful for the patient to bear weight on the knee, and passive motion of the knee elicits some pain. There is laxity at the knee to varus stress. The patient is wondering when he can return to athletics. Which of the following is the most likely diagnosis?
Q174
A 29-year-old man is brought to the emergency department 20 minutes after sustaining a gunshot wound to the abdomen. On arrival, he is awake and oriented to person, place, and time. He appears agitated. His pulse is 102/min, respirations are 20/min, and blood pressure is 115/70 mm Hg. The pupils are equal and reactive to light. Abdominal examination shows an entrance wound in the right upper quadrant above the umbilicus. There is an exit wound on the right lower back next to the lumbar spine. Breath sounds are normal bilaterally. There is diffuse mild tenderness to palpation with no guarding or rebound. Cardiac examination shows no abnormalities. Intravenous fluid therapy is begun. Which of the following is the most appropriate next step in management?
Q175
A 28-year-old man is admitted to the emergency department with a gunshot wound to the abdomen. He complains of weakness and diffuse abdominal pain. Morphine is administered and IV fluids are started by paramedics at the scene. On admission, the patient’s blood pressure is 90/60 mm Hg, heart rate is 103/min, respiratory rate is 17/min, the temperature is 36.2℃ (97.1℉), and oxygen saturation is 94% on room air. The patient is responsive but lethargic. The patient is diaphoretic and extremities are pale and cool. Lungs are clear to auscultation. Cardiac sounds are diminished. Abdominal examination shows a visible bullet entry wound in the left upper quadrant (LUQ) with no corresponding exit wound on the flanks or back. The abdomen is distended and diffusely tender with a rebound. Aspiration of the nasogastric tube reveals bloody contents. Rectal examination shows no blood. Stool guaiac is negative. Which of the following is the next best step in management?
Q176
A 68-year-old woman presents with shortness of breath and left-sided chest pain for a week. She says that her breathlessness is getting worse, and the chest pain is especially severe when she takes a deep breath. The patient denies any similar symptoms in the past. Her past medical history is insignificant except for occasional heartburn. She currently does not take any medication. She is a nonsmoker and drinks alcohol occasionally. She denies the use of any illicit drugs including marijuana. Vital signs are: blood pressure 122/78 mm Hg, pulse 67/min, respiratory rate 20/min, temperature 37.2°C (99.0°F). Her physical examination is remarkable for diminished chest expansion on the left side, absence of breath sounds at the left lung base, and dullness to percussion and decreased tactile fremitus on the left. A plain radiograph of the chest reveals a large left-sided pleural effusion occupying almost two-thirds of the left lung field. Thoracentesis is performed, and 2 L of fluid is drained from the thorax under ultrasound guidance. Which of the following patient positions and points of entry is the safest for performing a thoracentesis in this patient?
Q177
A 68-year-old man is brought to the emergency department because of fever, progressive weakness, and cough for the past five days. He experienced a similar episode 2 months ago, for which he was hospitalized for 10 days while visiting his son in Russia. He states that he has never fully recovered from that episode. He felt much better after being treated with antibiotics, but he still coughs often during meals. He sometimes also coughs up undigested food after eating. For the last 5 days, his coughing has become more frequent and productive of yellowish-green sputum. He takes hydrochlorothiazide for hypertension and pantoprazole for the retrosternal discomfort that he often experiences while eating. He has smoked half a pack of cigarettes daily for the last 30 years and drinks one shot of vodka every day. The patient appears thin. His temperature is 40.1°C (104.2°F), pulse is 118/min, respirations are 22/min, and blood pressure is 125/90 mm Hg. Auscultation of the lungs shows right basal crackles. There is dullness on percussion at the right lung base. The remainder of the physical examination shows no abnormalities. Laboratory studies show:
Hemoglobin 15.4 g/dL
Leukocyte count 17,000/mm3
Platelet count 350,000/mm3
Na+ 139 mEq/L
K+
4.6 mEq/L
Cl- 102 mEq/L
HCO3- 25 mEq/L
Urea Nitrogen 16 mg/dL
Creatinine 1.3 mg/dL
An x-ray of the chest shows a right lower lobe infiltrate. Which of the following is the most likely explanation for this patient's symptoms?
Q178
A 23-year-old woman presents to her primary care physician for knee pain. The pain started yesterday and has not improved since then. The patient is generally in good health. She attends college and plays soccer for her school's team. Three days ago, she was slide tackled during a game and her leg was struck from the inside. She fell to the ground and sat out for the rest of the game. It was not until yesterday that she noticed swelling in her knee. She also feels as if her knee is unstable and does not feel confident bearing weight on her leg during athletic activities. Her past medical history is notable for asthma, which is currently treated with an albuterol inhaler. On physical exam, you note bruising over her leg, knee, and medial thigh, and edema of her knee. Passive range of motion of the knee is notable only for minor clicking and catching of the joint. The patient's gait appears normal, though the patient states that her injured knee does not feel stable. Further physical exam is performed and imaging is ordered. Which of the following is the most likely diagnosis?
Q179
A 56-year-old man is brought to the emergency department after falling 16 feet from a ladder. He has severe pain in both his legs and his right arm. He appears pale and diaphoretic. His temperature is 37.5°C (99.5°F), pulse is 120/min and weak, respirations are 26/min, and blood pressure is 80/50 mm Hg. He opens his eyes and withdraws in response to painful stimuli and makes incomprehensible sounds. The abdomen is soft and nontender. All extremities are cold, with 1+ pulses distally. Arterial blood gas analysis on room air shows:
pH 7.29
PCO2 33 mm Hg
PO2 65 mm Hg
HCO3- 15 mEq/L
A CT scan shows displaced fractures of the pelvic ring, as well as fractures of both tibiae, the right distal radius, and right proximal humerus. The patient undergoes emergent open reduction and is admitted to the intensive care unit. Which of the following best indicates inadequate fluid resuscitation?
Q180
A 22-year-old man is brought to the emergency department because of progressive left-sided scrotal pain for 4 hours. He describes the pain as throbbing in nature and 6 out of 10 in intensity. He has vomited once on the way to the hospital. He has had pain during urination for the past 4 days. He has been sexually active with 2 female partners over the past year and uses condoms inconsistently. His father was diagnosed with testicular cancer at the age of 51 years. He appears anxious. His temperature is 36.9°C (98.42°F), pulse is 94/min, and blood pressure is 124/78 mm Hg. Cardiopulmonary examination shows no abnormalities. The abdomen is soft and nontender. Examination shows a tender, swollen left testicle and an erythematous left hemiscrotum. Urine dipstick shows leukocyte esterase; urinalysis shows WBCs. Which of the following is the most appropriate next step in management?
Trauma/Emergencies US Medical PG Practice Questions and MCQs
Question 171: A 66-year-old man presents to the emergency department for a 1-hour history of right arm weakness. He was having breakfast this morning when his right arm suddenly became weak, causing him to drop his coffee mug. He also noticed that he was slurring his speech and had some additional weakness in his right leg. He had no symptoms prior to the onset of the weakness and noted no other unusual phenomena. These symptoms lasted for about 30 minutes, but they resolved completely by the time he arrived at the emergency department. His medical history is notable for hypertension and hyperlipidemia, but he does not receive close follow-up from a primary care physician for these conditions. The patient currently is not taking any medications. His pulse is 75/min, the blood pressure is 160/95 mm Hg, and the respiratory rate is 14/min. Physical exam is remarkable for a high-pitched sound heard on auscultation of the neck, the remainder of the exam, including a complete neurological exam, is entirely unremarkable. CT angiography of the head and neck shows no active hemorrhage and 80% stenosis of the left internal carotid artery. Which of the following is the next best step in the long-term management of this patient?
A. Administration of tissue plasminogen activator (tPA)
B. Brain MRI
C. Initiation of lisinopril
D. Initiation of aspirin and atorvastatin (Correct Answer)
E. Carotid endarterectomy
Explanation: ***Initiation of aspirin and atorvastatin***
- This patient experienced a **transient ischemic attack (TIA)** as evidenced by transient neurological symptoms (right-sided weakness, slurred speech) that resolved completely within 24 hours. The presence of **80% left internal carotid artery stenosis** and a **carotid bruit** identifies the source of the embolic event.
- **Antiplatelet therapy (aspirin)** and **high-intensity statin therapy (atorvastatin)** are critical for **secondary stroke prevention** in patients with TIA due to atherosclerotic disease. Aspirin reduces platelet aggregation, and atorvastatin stabilizes plaques and lowers cholesterol.
*Administration of tissue plasminogen activator (tPA)*
- **tPA** is indicated for **acute ischemic stroke** within a specific time window (typically 3-4.5 hours from symptom onset) and requires confirmation of **active stroke (not TIA)** and absence of contraindications. This patient's symptoms **resolved completely**, indicating a TIA, not an acute ischemic stroke that would benefit from tPA.
- Furthermore, tPA carries a significant risk of **hemorrhagic transformation**, which is not warranted in a patient whose symptoms have already resolved.
*Brain MRI*
- While a **brain MRI** (diffusion-weighted imaging) is highly sensitive for detecting acute ischemic changes and can help confirm a TIA diagnosis by ruling out small infarcts, it is not the **next best step in long-term management** after already identifying significant carotid stenosis as the likely source.
- The immediate priority for long-term management is to prevent future, potentially disabling, ischemic events through medical therapy.
*Initiation of lisinopril*
- **Lisinopril**, an ACE inhibitor, is an appropriate medication for managing **hypertension**, which is a significant risk factor for TIA and stroke. The patient's blood pressure of 160/95 mmHg indicates uncontrolled hypertension.
- However, while important for overall cardiovascular health, **blood pressure control alone** is not the most immediate and comprehensive step for **secondary prevention of ischemic events** given the specific finding of significant carotid stenosis; **antiplatelet and statin therapy** are more directly targeted at preventing recurrent embolic events from the plaque.
*Carotid endarterectomy*
- **Carotid endarterectomy (CEA)** is a surgical procedure to remove atherosclerotic plaque from the carotid artery and is considered for patients with symptomatic **carotid artery stenosis of 70-99%**. Given the 80% stenosis, this procedure is a strong consideration.
- However, for patients with symptomatic carotid stenosis, medical management (aspirin and statin) is typically **initiated first** and often continued even after CEA. CEA, while highly effective, is an invasive procedure with its own risks and requires careful patient selection and timing in conjunction with optimal medical therapy.
Question 172: Paramedics are called to a 35-year-old man who had accidentally amputated his left index finger tip with a knife. He has no significant past medical history. His temperature is 37.2°C (99°F), pulse is 96/min, and blood pressure is 112/72 mm Hg. Pulse oximetry on room air shows an oxygen saturation of 99%. His left index finger is amputated distal to the distal interphalangeal joint at the level of the nail bed, and exposed bone is visible. There is profuse bleeding from the wound site. His ability to flex, extend, abduct, and adduct the joints is preserved and sensation is intact. The remainder of the examination shows no abnormalities. Which of the following is the most appropriate next step prior to transporting this patient to the emergency department?
A. Preserve finger tip in warm saline water
B. Wrap finger tip in gauze damp with saline in a sealed plastic bag placed on ice water (Correct Answer)
C. Wrap finger in gauze wet with iodine in a sealed plastic bag placed on ice
D. Place finger tip on ice in a sealed plastic bag
E. Preserve finger tip in cooled saline water
Explanation: ***Wrap finger tip in gauze damp with saline in a sealed plastic bag placed on ice water***
- This method ensures the **amputated part** remains **moist** and **cool** without direct contact with ice, which can cause **frostbite** and damage tissue viability.
- The use of saline-dampened gauze prevents **desiccation**, while the sealed bag and ice water maintain a **hypothermic environment**, crucial for preserving tissue for potential **replantation**.
*Preserve finger tip in warm saline water*
- **Warm temperatures** accelerate **tissue degradation** and reduce the viability of the amputated part for replantation.
- While saline prevents desiccation, the warmth is detrimental to **ischemic tissue**.
*Wrap finger in gauze wet with iodine in a sealed plastic bag placed on ice*
- **Iodine** is a **cytotoxic agent** that can damage delicate tissues and compromise the viability of the amputated part.
- While cooling is important, the use of iodine makes this method unsuitable for preserving tissue for replantation.
*Place finger tip on ice in a sealed plastic bag*
- **Direct contact with ice** can lead to **frostbite** and **ischemic damage** to the amputated tissue, severely reducing the chances of successful replantation.
- Although cooling is beneficial, it must be done indirectly to protect the tissue from freezing.
*Preserve finger tip in cooled saline water*
- While cooling is appropriate and saline prevents desiccation, immersing the tissue directly in water, even cooled saline, can cause **tissue maceration** and **cell lysis** due to osmotic effects.
- The preferred method involves indirect cooling with a damp dressing to maintain optimal moisture and temperature without direct immersion.
Question 173: A 23-year-old male presents to his primary care physician after an injury during a rugby game. The patient states that he was tackled and ever since then has had pain in his knee. The patient has tried NSAIDs and ice to no avail. The patient has no past medical history and is currently taking a multivitamin, fish oil, and a whey protein supplement. On physical exam you note a knee that is heavily bruised. It is painful for the patient to bear weight on the knee, and passive motion of the knee elicits some pain. There is laxity at the knee to varus stress. The patient is wondering when he can return to athletics. Which of the following is the most likely diagnosis?
A. Lateral collateral ligament tear (Correct Answer)
B. Posterior cruciate ligament tear
C. Meniscal tear
D. Medial collateral ligament tear
E. Anterior cruciate ligament tear
Explanation: ***Lateral collateral ligament tear***
- **Varus stress laxity** is a classic sign of LCL injury, where the knee opens up on the lateral side when forced inward.
- An LCL tear often results from a **direct blow to the medial side of the knee** or excessive varus (inward) force, consistent with a rugby tackle.
*Posterior cruciate ligament tear*
- A PCL tear specifically presents with a **posterior drawer sign**, indicating posterior instability of the tibia relative to the femur.
- This injury is often caused by a **direct blow to the anterior tibia** when the knee is flexed or a hyperextension injury.
*Meniscal tear*
- A meniscal tear typically presents with mechanical symptoms like **locking, clicking, or catching**, which are not mentioned here.
- Pain is often localized to the **joint line** and may worsen with rotation or squatting movements.
*Medial collateral ligament tear*
- An MCL tear would present with **valgus stress laxity**, where the knee opens up on the medial side when forced outward.
- This injury commonly occurs from a **direct blow to the lateral side of the knee** or excessive valgus (outward) force.
*Anterior cruciate ligament tear*
- An ACL tear often presents with a **"pop" sound**, immediate swelling (hemarthrosis), and instability, particularly during pivot movements.
- Physical exam would reveal a **positive Lachman test** or anterior drawer sign, which are not mentioned.
Question 174: A 29-year-old man is brought to the emergency department 20 minutes after sustaining a gunshot wound to the abdomen. On arrival, he is awake and oriented to person, place, and time. He appears agitated. His pulse is 102/min, respirations are 20/min, and blood pressure is 115/70 mm Hg. The pupils are equal and reactive to light. Abdominal examination shows an entrance wound in the right upper quadrant above the umbilicus. There is an exit wound on the right lower back next to the lumbar spine. Breath sounds are normal bilaterally. There is diffuse mild tenderness to palpation with no guarding or rebound. Cardiac examination shows no abnormalities. Intravenous fluid therapy is begun. Which of the following is the most appropriate next step in management?
A. Diagnostic laparoscopy
B. Close observation
C. Diagnostic peritoneal lavage
D. CT scan of the abdomen
E. Immediate laparotomy (Correct Answer)
Explanation: ***Immediate laparotomy***
- **All gunshot wounds (GSW) to the abdomen require immediate surgical exploration**, regardless of hemodynamic stability, as they have a >90% rate of significant intraperitoneal injury requiring operative repair.
- Unlike stab wounds (which may be managed selectively), **GSWs mandate laparotomy** due to the high-velocity nature causing unpredictable tissue damage and the near-certainty of organ injury.
- The bullet trajectory from right upper quadrant to right lower back suggests potential injuries to the **liver, right kidney, colon, and retroperitoneal structures**, all of which require direct visualization and surgical repair.
- Hemodynamic stability does NOT change the indication for immediate operative intervention in abdominal GSWs.
*CT scan of the abdomen*
- While CT is useful for **blunt abdominal trauma** or **selective management of stab wounds** in hemodynamically stable patients, it is **not indicated for gunshot wounds to the abdomen**.
- CT imaging would only delay definitive surgical treatment and does not change management, as laparotomy is required regardless of CT findings.
- The only exception might be tangential wounds with clear extraperitoneal trajectory, which is not the case here.
*Diagnostic laparoscopy*
- Diagnostic laparoscopy has a limited role in trauma and may miss retroperitoneal and diaphragmatic injuries.
- It is sometimes used for **equivocal stab wounds**, but not for GSWs where exploratory laparotomy is the standard of care.
*Close observation*
- **Absolutely contraindicated** for penetrating abdominal gunshot wounds due to the extremely high likelihood (>90%) of significant intra-abdominal injury.
- Even hemodynamically stable patients can have life-threatening injuries requiring surgical repair (bowel perforation, solid organ injury, vascular injury).
*Diagnostic peritoneal lavage*
- DPL was historically used for detecting intra-abdominal bleeding in **blunt trauma** but has been largely replaced by FAST and CT scanning.
- It is **not indicated for GSWs**, which already have a clear indication for laparotomy without need for additional diagnostic testing.
- DPL cannot provide anatomical detail and does not guide operative planning.
Question 175: A 28-year-old man is admitted to the emergency department with a gunshot wound to the abdomen. He complains of weakness and diffuse abdominal pain. Morphine is administered and IV fluids are started by paramedics at the scene. On admission, the patient’s blood pressure is 90/60 mm Hg, heart rate is 103/min, respiratory rate is 17/min, the temperature is 36.2℃ (97.1℉), and oxygen saturation is 94% on room air. The patient is responsive but lethargic. The patient is diaphoretic and extremities are pale and cool. Lungs are clear to auscultation. Cardiac sounds are diminished. Abdominal examination shows a visible bullet entry wound in the left upper quadrant (LUQ) with no corresponding exit wound on the flanks or back. The abdomen is distended and diffusely tender with a rebound. Aspiration of the nasogastric tube reveals bloody contents. Rectal examination shows no blood. Stool guaiac is negative. Which of the following is the next best step in management?
A. Focused assessment with sonography for trauma (FAST)
B. Abdominal CT
C. Exploratory laparotomy (Correct Answer)
D. Abdominal X-ray
E. Diagnostic peritoneal lavage
Explanation: ***Exploratory laparotomy***
- The patient presents with clear signs of **hemodynamic instability** (BP 90/60 mmHg, HR 103/min, lethargy, cool extremities, diminished cardiac sounds) following a **gunshot wound to the abdomen**.
- In hemodynamically unstable trauma patients with penetrating abdominal injuries, immediate **exploratory laparotomy** is indicated to identify and control hemorrhage and repair organ damage.
*Focused assessment with sonography for trauma (FAST)*
- While FAST can detect free fluid (e.g., blood) in the abdomen, it is **not sufficient to rule out significant injury** in a hemodynamically unstable patient with a penetrating abdominal wound.
- A positive FAST in a stable patient might prompt further imaging, but in this unstable case, it would delay definitive surgical intervention.
*Abdominal CT*
- Abdominal CT is useful for evaluating intra-abdominal injuries in **hemodynamically stable** patients.
- Performing a CT on this unstable patient would delay critical surgical intervention and could lead to rapid deterioration in the scanner.
*Abdominal X-ray*
- An abdominal X-ray can sometimes identify the **location of a bullet** or **free air** under the diaphragm, but it has limited utility in assessing or quantifying intra-abdominal hemorrhage or solid organ injury.
- It is not the definitive diagnostic or therapeutic step for an unstable patient with a penetrating abdominal injury.
*Diagnostic peritoneal lavage*
- DPL is an invasive procedure that can detect intra-abdominal bleeding or perforation, but it has largely been **replaced by FAST and CT scans** in hemodynamically stable patients.
- For a hemodynamically unstable patient with a clear indication for surgery (penetrating trauma and instability), DPL would delay definitive surgical management and provides less information than direct visualization via laparotomy.
Question 176: A 68-year-old woman presents with shortness of breath and left-sided chest pain for a week. She says that her breathlessness is getting worse, and the chest pain is especially severe when she takes a deep breath. The patient denies any similar symptoms in the past. Her past medical history is insignificant except for occasional heartburn. She currently does not take any medication. She is a nonsmoker and drinks alcohol occasionally. She denies the use of any illicit drugs including marijuana. Vital signs are: blood pressure 122/78 mm Hg, pulse 67/min, respiratory rate 20/min, temperature 37.2°C (99.0°F). Her physical examination is remarkable for diminished chest expansion on the left side, absence of breath sounds at the left lung base, and dullness to percussion and decreased tactile fremitus on the left. A plain radiograph of the chest reveals a large left-sided pleural effusion occupying almost two-thirds of the left lung field. Thoracentesis is performed, and 2 L of fluid is drained from the thorax under ultrasound guidance. Which of the following patient positions and points of entry is the safest for performing a thoracentesis in this patient?
A. With the patient in the sitting position, just above the fifth rib in the anterior axillary line
B. With the patient in the supine position, in the fifth intercostal space right below the nipple
C. With the patient in the supine position, just above the fifth rib in the midaxillary line
D. With the patient in the sitting position, at the midclavicular line on the second intercostal space
E. With the patient in the sitting position, below the tip of the scapula midway between the spine and the posterior axillary line on the superior margin of the eighth rib (Correct Answer)
Explanation: ***With the patient in the sitting position, below the tip of the scapula midway between the spine and the posterior axillary line on the superior margin of the eighth rib***
- This position and entry point are ideal because the patient is **sitting upright**, allowing the fluid to pool dependently at the base of the lung, and the insertion site is chosen to avoid major anatomical structures.
- The entry point ensures the needle is inserted **on the superior margin of the eighth rib** (8th intercostal space), reducing the risk of damaging the intercostal neurovascular bundle which runs along the inferior margin of the rib.
*With the patient in the sitting position, just above the fifth rib in the anterior axillary line*
- This location is too high anteriorly and risks damage to the **heart** or **major vessels**, especially with a large effusion.
- It also increases the likelihood of causing a **pneumothorax** because the lung may not be fully compressed by the pleural fluid in this area.
*With the patient in the supine position, in the fifth intercostal space right below the nipple*
- The **supine position** is not optimal for thoracentesis as it does not allow gravity to aid in fluid collection, making it harder to localize the fluid and increasing the risk of puncturing the lung.
- While the fifth intercostal space can be used, the **nipple line** is an imprecise landmark and may still be quite anterior, posing a risk to the heart.
*With the patient in the supine position, just above the fifth rib in the midaxillary line*
- Similar to the previous option, the **supine position** is generally avoided for thoracentesis unless absolutely necessary, due to the difficulty in fluid localization and increased risk.
- While the midaxillary line is a common site, a higher insertion point like the fifth rib may still be too high with respect to the diaphragm, and the **supine position** may cause diaphragmatic elevation.
*With the patient in the sitting position, at the midclavicular line on the second intercostal space*
- The **midclavicular line on the second intercostal space** is the standard site for **needle decompression of a tension pneumothorax**, not for thoracentesis of a pleural effusion.
- This site is too high and anterior for draining pleural fluid and risks injury to the **lung parenchyma** and **major vessels** without sufficient fluid accumulation there.
Question 177: A 68-year-old man is brought to the emergency department because of fever, progressive weakness, and cough for the past five days. He experienced a similar episode 2 months ago, for which he was hospitalized for 10 days while visiting his son in Russia. He states that he has never fully recovered from that episode. He felt much better after being treated with antibiotics, but he still coughs often during meals. He sometimes also coughs up undigested food after eating. For the last 5 days, his coughing has become more frequent and productive of yellowish-green sputum. He takes hydrochlorothiazide for hypertension and pantoprazole for the retrosternal discomfort that he often experiences while eating. He has smoked half a pack of cigarettes daily for the last 30 years and drinks one shot of vodka every day. The patient appears thin. His temperature is 40.1°C (104.2°F), pulse is 118/min, respirations are 22/min, and blood pressure is 125/90 mm Hg. Auscultation of the lungs shows right basal crackles. There is dullness on percussion at the right lung base. The remainder of the physical examination shows no abnormalities. Laboratory studies show:
Hemoglobin 15.4 g/dL
Leukocyte count 17,000/mm3
Platelet count 350,000/mm3
Na+ 139 mEq/L
K+
4.6 mEq/L
Cl- 102 mEq/L
HCO3- 25 mEq/L
Urea Nitrogen 16 mg/dL
Creatinine 1.3 mg/dL
An x-ray of the chest shows a right lower lobe infiltrate. Which of the following is the most likely explanation for this patient's symptoms?
A. Weak tone of the lower esophageal sphincter
B. Unrestricted growth of pneumocytes with invasion of the surrounding tissue
C. Uncoordinated contractions of the esophagus
D. Formation of a tissue cavity containing necrotic debris
E. Outpouching of the hypopharynx (Correct Answer)
Explanation: ***Outpouching of the hypopharynx***
- The patient's history of coughing up undigested food and coughing during meals suggests **dysphagia** and potential **aspiration**, which can be caused by a **Zenker's diverticulum** (an outpouching of the hypopharynx).
- This condition creates a pouch that can trap food, leading to regurgitation and repeated aspiration pneumonia, as evidenced by his recurrent pneumonia and current symptoms.
- Zenker's diverticulum is the **underlying explanation** that accounts for *all* of this patient's symptoms: the regurgitation of undigested food, dysphagia, and recurrent aspiration pneumonia.
*Weak tone of the lower esophageal sphincter*
- A weak lower esophageal sphincter (LES) primarily causes **gastroesophageal reflux disease (GERD)**, often associated with heartburn and regurgitation of stomach contents, not undigested food.
- While GERD can cause aspiration, the coughing up of *undigested food* is more indicative of a proximal esophageal issue or pharyngeal problem.
*Unrestricted growth of pneumocytes with invasion of the surrounding tissue*
- This describes **lung cancer**, which can present with cough, weight loss, and recurrent pneumonia due to bronchial obstruction.
- However, the symptom of coughing up *undigested food* is not typical of primary lung malignancy, and the history strongly points to a swallowing disorder.
*Uncoordinated contractions of the esophagus*
- This refers to esophageal motility disorders like **achalasia** or **diffuse esophageal spasm**, which can cause dysphagia and regurgitation.
- While these can lead to aspiration, the specific complaint of coughing up *undigested food* *after eating* is more characteristic of a pharyngeal pouch (Zenker's diverticulum) rather than general esophageal dysmotility.
*Formation of a tissue cavity containing necrotic debris*
- This describes a **lung abscess**, which is a possible *complication* of aspiration pneumonia, accounting for the fever, productive cough, and infiltrate.
- However, the question asks for the **most likely explanation** for this patient's symptoms—a lung abscess is a *sequela* of aspiration, not the *underlying cause* of the repeated aspiration events.
- It does not explain the pathognomonic finding of coughing up undigested food after eating, which points to Zenker's diverticulum as the root cause.
Question 178: A 23-year-old woman presents to her primary care physician for knee pain. The pain started yesterday and has not improved since then. The patient is generally in good health. She attends college and plays soccer for her school's team. Three days ago, she was slide tackled during a game and her leg was struck from the inside. She fell to the ground and sat out for the rest of the game. It was not until yesterday that she noticed swelling in her knee. She also feels as if her knee is unstable and does not feel confident bearing weight on her leg during athletic activities. Her past medical history is notable for asthma, which is currently treated with an albuterol inhaler. On physical exam, you note bruising over her leg, knee, and medial thigh, and edema of her knee. Passive range of motion of the knee is notable only for minor clicking and catching of the joint. The patient's gait appears normal, though the patient states that her injured knee does not feel stable. Further physical exam is performed and imaging is ordered. Which of the following is the most likely diagnosis?
A. Iliotibial band syndrome
B. Lateral meniscal tear (Correct Answer)
C. Medial collateral ligament tear
D. Anterior cruciate ligament tear
E. Posterior cruciate ligament tear
Explanation: ***Lateral meniscal tear***
- The sensation of **clicking and catching** in the knee joint during passive range of motion is highly suggestive of a **meniscal tear**.
- The mechanism of injury (force from the **inside** of the knee creating **varus stress**) and subsequent **instability** during athletic activities are consistent with **lateral** meniscal damage.
- Delayed onset of swelling (1-2 days post-injury) is typical for meniscal tears, as opposed to immediate hemarthrosis seen with ligamentous injuries.
*Iliotibital band syndrome*
- Characterized by **lateral knee pain** caused by friction between the **iliotibial band** and the lateral femoral epicondyle, often seen in runners.
- It typically presents as a **gradual onset** of pain with repetitive activities, not an acute injury with immediate swelling and instability following trauma.
*Medial collateral ligament tear*
- This injury commonly results from a **valgus stress** (force to the **outside** of the knee) and would primarily cause **medial knee pain** and valgus instability on examination.
- The mechanism described (medial blow/varus stress) does not match MCL injury patterns, and the prominent "clicking and catching" is more characteristic of meniscal pathology.
*Anterior cruciate ligament tear*
- ACL tears present with immediate onset of **severe pain**, rapid **swelling (hemarthrosis)** within hours, and typically a "popping" sensation at the time of injury.
- While instability is also a key feature, the **delayed swelling** (occurred 2 days post-injury) and presence of "clicking and catching" makes a meniscal tear the more likely primary diagnosis.
*Posterior cruciate ligament tear*
- PCL tears usually result from a direct blow to the **anterior knee** when the knee is flexed (e.g., dashboard injury) or a **hyperextension injury**.
- Symptoms include posterior knee pain and a positive posterior drawer test, but "clicking and catching" is not a hallmark symptom of isolated PCL injury.
Question 179: A 56-year-old man is brought to the emergency department after falling 16 feet from a ladder. He has severe pain in both his legs and his right arm. He appears pale and diaphoretic. His temperature is 37.5°C (99.5°F), pulse is 120/min and weak, respirations are 26/min, and blood pressure is 80/50 mm Hg. He opens his eyes and withdraws in response to painful stimuli and makes incomprehensible sounds. The abdomen is soft and nontender. All extremities are cold, with 1+ pulses distally. Arterial blood gas analysis on room air shows:
pH 7.29
PCO2 33 mm Hg
PO2 65 mm Hg
HCO3- 15 mEq/L
A CT scan shows displaced fractures of the pelvic ring, as well as fractures of both tibiae, the right distal radius, and right proximal humerus. The patient undergoes emergent open reduction and is admitted to the intensive care unit. Which of the following best indicates inadequate fluid resuscitation?
A. Urine output of 25 mL in 3 hours (Correct Answer)
B. Capillary refill time of 3 seconds
C. Base deficit of 1 mmol/L
D. Glasgow coma score of 8
E. High pulse pressure
Explanation: ***Urine output of 25 mL in 3 hours***
- A critically low urine output of **less than 0.5 mL/kg/hr** (or <30 mL/hr in an adult) over several hours is a direct and sensitive indicator of **renal hypoperfusion** due to inadequate fluid resuscitation, especially in the context of traumatic shock.
- Oliguria suggests that the kidneys are not receiving sufficient blood flow to maintain normal function, indicating persistent systemic hypovolemia despite initial interventions.
*Capillary refill time of 3 seconds*
- A capillary refill time of 3 seconds, while slightly prolonged (normal <2 seconds), is less definitive for **severe ongoing hypovolemia** compared to oliguria.
- It can be influenced by factors like **ambient temperature** and peripheral vasoconstriction, which are common in trauma but may not solely reflect inadequate fluid volume.
*Base deficit of 1 mmol/L*
- A base deficit of 1 mmol/L is essentially **within the normal range** (typically -2 to +2 mmol/L).
- A normal or low base deficit suggests that **tissue perfusion is adequate** and there's no significant ongoing metabolic acidosis due to anaerobic metabolism, making it an indicator of *adequate* rather than *inadequate* resuscitation.
*Glasgow coma score of 8*
- A Glasgow Coma Scale (GCS) score of 8 (Eyes: 2, Verbal: 2, Motor: 4 from the stem) indicates **moderate head injury** or altered mental status.
- While hypovolemic shock can affect mentation, a GCS of 8 is more indicative of **neurological damage** (e.g., from head trauma sustained in the fall) or other systemic issues rather than being a primary measure of fluid resuscitation status.
*High pulse pressure*
- A high pulse pressure (the difference between systolic and diastolic blood pressure) is typically seen in conditions like **sepsis** or **aortic regurgitation**.
- In a patient with hypovolemic shock, **pulse pressure is usually narrowed** due to increased peripheral vascular resistance and decreased stroke volume.
Question 180: A 22-year-old man is brought to the emergency department because of progressive left-sided scrotal pain for 4 hours. He describes the pain as throbbing in nature and 6 out of 10 in intensity. He has vomited once on the way to the hospital. He has had pain during urination for the past 4 days. He has been sexually active with 2 female partners over the past year and uses condoms inconsistently. His father was diagnosed with testicular cancer at the age of 51 years. He appears anxious. His temperature is 36.9°C (98.42°F), pulse is 94/min, and blood pressure is 124/78 mm Hg. Cardiopulmonary examination shows no abnormalities. The abdomen is soft and nontender. Examination shows a tender, swollen left testicle and an erythematous left hemiscrotum. Urine dipstick shows leukocyte esterase; urinalysis shows WBCs. Which of the following is the most appropriate next step in management?
A. Scrotal ultrasonography (Correct Answer)
B. CT scan of the abdomen and pelvis
C. Surgical exploration
D. Measurement of serum mumps IgG titer
E. Measurement of serum α-fetoprotein level
Explanation: ***Scrotal ultrasonography***
- A definitive diagnosis of **epididymitis**, **orchitis**, or **testicular torsion** requires imaging, which can confirm blood flow to the testis.
- Given the symptoms of testicular pain, tenderness, and inflammation in a sexually active young man, **epididymitis** is highly suspected, but **testicular torsion** must be ruled out as it's a surgical emergency.
*CT scan of the abdomen and pelvis*
- This imaging modality is **not indicated** for the initial evaluation of acute scrotal pain.
- While it can identify other intra-abdominal pathology, it does **not provide sufficient detail** of the scrotal contents or blood flow.
*Surgical exploration*
- **Surgical exploration** is the treatment for **testicular torsion**, but it should only be performed after a clinical or ultrasound diagnosis of testicular torsion is made.
- Doing an immediate surgical exploration without imaging may result in unnecessary surgery if the patient has epididymitis.
*Measurement of serum mumps IgG titer*
- While **mumps orchitis** can cause testicular pain, this patient has symptoms more consistent with an infection related to sexual activity or a potential torsion.
- Measuring mumps titers would **delay diagnosis** and management for more urgent conditions like testicular torsion.
*Measurement of serum α-fetoprotein level*
- **Alpha-fetoprotein (AFP)** is a tumor marker primarily used for the diagnosis and monitoring of **testicular cancer**.
- This patient presents with acute pain and inflammatory signs, which are **not typical for testicular cancer**; AFP measurement is not indicated in the acute setting.