Block 21 Explanations
1) A 62-year-old man complains of perineal discomfort and reports that there are streaks of fecal soiling in his underwear. Four months ago, he had a perirectal abscess drained surgically. Physical examination shows a perineal opening in the skin lateral to the anus, and a cord-like tract can be palpated going from the opening toward the inside of the anal canal. Brownish purulent discharge can be expressed from the tract. Which of the following is the most likely diagnosis?
A. Anal fissure
B. Anorectal carcinoma
C. Fistula-in-ano
D. Pilonidal cyst
E. Thrombosed hemorrhoids
Explanation:
The correct answer is
C. The recent history of a drained perirectal abscess, along with the physical description of the current lesion, clearly identify this as a fistula-in-ano. Anal fissure (choice A) typically occurs in young women, who have exquisite pain with defecation and blood streaks in the stool. The lesion is in the anal mucosa, not in the nearby perineal skin. Anorectal carcinoma (choice B) always has to be ruled out in any patient with anorectal complaints, particularly those describing blood in the stool. In advanced cases, it can show up as an ulcerated, draining mass. But, it would not be a discrete opening with no obvious tumor mass, such as described here. Pilonidal cyst (choice D) is a good distracter, because they get infected, hurt, drain pus, soil the underwear, and have a skin opening. However, the opening is always cephalad to the anus, near the midline; the drainage is pus, not feces; and there is no connection with recent perirectal abscess. Thrombosed hemorrhoids (choice E) would produce excruciating pain, and appear as a small. red, angry, mass protruding out of the anus. If they drain spontaneously, blood and clot, not feces, come out.
2) A 72-year-old man of Norwegian ancestry has a contracted hand that can no longer be extended and placed flat on a table. The problem developed gradually, over many years. He complains of no pain or neurologic abnormalities and, to the extent that the deformity allows, can move his fingers at will. Physical examination demonstrates the deformity described and in addition shows the presence of palpable fascial nodules. Which of the following is the most likely diagnosis?
A. Carpal tunnel syndrome
B. De Quervain tenosynovitis
C. Dupuytren contracture
D. Palmar tenosynovitis
E. Rheumatoid arthritis
Explanation:
The correct answer is
C. Older men of Scandinavian descent are the victims of this otherwise mysterious contracture. The palpable nodules are classic, as is the deformity itself. Carpal tunnel syndrome (choice A) affects mostly young women, and the symptoms are tingling and numbness, without a deformity. De Quervain tenosynovitis (choice B) is seen in young women who complain of pain on the radial side of the wrist. There is no deformity. Tenosynovitis of any kind (choice D) would produce pain and limitation to the movement of the fingers Rheumatoid arthritis (choice E) is also a painful condition, and the deformity is classic along the joints, rather than in the palm of the hand.
3) A 44-year-old man complains of vague right upper abdominal discomfort that he has had for about 1 month. He describes no other symptoms, and, except for enucleation of one eye at age 21 “for a tumor,” he has been in excellent health all his life. He exercises regularly and neither smokes nor drinks. The only findings on physical examination include the artificial eye and a tender, enlarged, and nodular liver. CT scan of the upper abdomen demonstrates multiple masses within the liver. Which of the following will most likely be found on biopsy of these masses?
A. Metastatic malignant melanoma
B. Metastatic prostatic cancer
C. Metastatic retinoblastoma
D. Metastatic sarcoma
E. Primary hepatocellular carcinoma
Explanation:
The correct answer is
A. There are two malignant tumors of the eye for which enucleation would be done: retinoblastoma and melanoma. Only melanoma would have this weird timetable, in which 20-some years may elapse between primary tumor and metastatic manifestations. In fact, the patient with a glass eye and a liver full of tumor is one of the two classic examples that are given (the other one has a missing toe) to illustrate the unpredictable behavior of melanoma. Prostatic cancer (choice B) can show up with metastases before we know the primary is there, but the metastatic site would usually be in bone. Retinoblastoma (choice C) can indeed lead to eye enucleation, but if it goes on to kill the patient (which it often does), it does not wait 20-odd years to do it. Sarcomas (choice D) metastasize via the blood stream but are rare in organs that drain via the portal system. Thus, they favor the lungs as the metastatic site. Furthermore, the primaries are seldom hidden. Primary hepatocellular carcinoma (choice E) is rare in the U.S., where it is outnumbered 20 to 1 by metastatic tumors. When it happens it is usually in a cirrhotic patient, not in an otherwise healthy person.
4) A 71-year-old West Texas farmer of Irish ancestry has a nonhealing, indolent, punched out, clean-looking 2-cm ulcer over the left temple. The ulcer has been slowly growing over the past 3 years. There are no enlarged lymph nodes in the head and neck. Which of the following would best dictate proper management?
A. Full thickness biopsy of the center of the lesion
B. Full thickness biopsy of the edge of the lesion
C. Pathologic studies after the entire lesion is resected with a margin of 1 cm of normal skin all around
D. Response to a trial of radiation therapy
E. Scrapings and culture of the ulcer base
Explanation:
The correct answer is
B. The history (a fair skinned person who is out in the sun all day) suggests a skin cancer, and the location (the upper part of the face) favors a basal cell cancer but does not exclude a squamous cell carcinoma, or even a melanoma. Thus, diagnosis is needed before proper therapy is instituted. The edge of the lesion offers the best information for the pathologist. A biopsy of the center of the lesion (choice A) deprives the pathologist of all the clues that are found at the interface between the tumor and the normal skin, and in large lesions it runs the risk of sampling necrotic tumor that has outgrown its blood supply. A wide excision before pathologic diagnosis (choice C) risks doing too much (a basal cell cancer needs only 1 or 2 mm of margins) or too little (a melanoma should have at least 2 cm). Radiation therapy (choice D) is a viable therapeutic choice for squamous cell carcinoma, but not before a diagnosis has been established. Here, we are expecting a basal cell carcinoma, thus this course of action would be even less appropriate. Scrapings and cultures (choice E) assume an infectious process, ignoring the strong clinical suspicion of a tumor in this case.
5) A pediatrician’s office gets a phone call from a frantic mother. Her 7-year-old daughter was playing under the sink and accidentally spilled Liquid Plumber (a strong, corrosive alkaline drain cleaner) all over her arms and legs. The nurse on the phone can hear the girl screaming in the background. Which of the following are the most appropriate instructions to give the mother?
A. Cover the burned areas with triple antibiotic ointment until the girl can be seen at the office
B. Get the girl into the shower right away and keep the water running over her for 30 minutes before bringing her to the emergency department
C. Get the girl to the emergency department as soon as possible
D. Wash the burned areas with diluted vinegar and bring the girl to the office
E. Wrap the burned areas in sterile dressings before bringing the girl to the emergency department
Explanation:
The correct answer is
B. By far the most important thing that can be done for caustic chemical burns is to wash away the caustic agent as soon as possible, and the best way to do that is with massive irrigation. Any answer that allows the chemical agent to stay in touch with the skin, whether mixed with antibiotic ointment (choice A), wrapped in bandages (choice E), or with no specific additional instructions (choice C) will result in continued burning for the time that it will take to get to the emergency department or physicians’ office. Washing with an acid (choice D) is particularly inadvisable. Except for chemical burns of the esophagus, for which massive irrigation cannot be done, one should never “play chemist” when dealing with alkaline or acid burns. The chemical reaction will generate heat and compound the problem.
6) A 59-year-old man sustains blunt trauma in an automobile accident, resulting in multiple intra-abdominal injuries. Surgery for the repair of these injuries takes several hours and requires multiple blood transfusions and infusions of Ringer’s lactate. Before all the operative steps are completed, the patient develops a significant coagulopathy, a core body temperature less than 34 C (93.2 F), and refractory acidosis. The anesthesiologists are administering fresh frozen plasma and platelet packs. Which of the following is the most appropriate next step in management for the surgeon?
A. Provide hemostasis by liberal use of electrocoagulation
B. Wash the abdomen with warm saline and continue to operate
C. Complete the operation as soon as possible and do a formal abdominal closure
D. Pack the bleeding surfaces and close the abdomen temporarily with towel clips
E. Abort the operation and leave the abdomen open, covering the bowel with mesh
Explanation:
The correct answer is
D. Indeed, the appropriate course of action when coagulopathy develops in these circumstances is to empirically provide fresh frozen plasma and platelet packs. However, when hypothermia complicates the picture, the abdomen also has to be closed immediately albeit temporarily in the most expeditious manner. The bleeding surfaces have to be packed, waiting for a more propitious time in which to attempt hemostasis, once coagulation function and body temperature have improved. Electrocoagulation (choice A) is not magic, it requires clotting on the part of the patient. If the abdomen is kept open to do it, the hypothermia gets worse. Warming the abdomen with saline (choice B) is not sufficient if the abdomen is kept open while surgery continues. Although moving along quickly (choice C) would be better than leisurely continuation of surgery, it is not fast enough under the circumstances. Besides, with no clotting one can never truly complete the operation. Aborting the operation (choice E) is the right thing to do, but leaving the belly open is not. Closure with mesh is indicated when the abdominal compartment syndrome prevents normal closure.
7) A 42-year-old man describes intermittent episodes of severe, crushing chest pain that extends to the back and the jaw and last anywhere from a few seconds to several minutes. Many times the pain is accompanied by dysphagia and triggered by the ingestion of very cold or very hot liquids. However, sometimes the pain occurs for no apparent reason. There is no history of regurgitation, and, although the problem has been present for many years, there has been no progression of the symptoms. Repeated ECGs and cardiac enzymes have always been negative. Barium swallow shows an area of “corkscrew” appearance. Manometry shows that about one half of wet swallows produce repetitive simultaneous esophageal contractions of the esophageal body, and that the lower esophageal sphincter has normal pressures and exhibits normal relaxation. Which of the following is the most likely diagnosis?
A. Achalasia of the esophagus
B. Cancer of the lower esophagus
C. Diffuse esophageal spasm
D. Nutcracker esophagus
E. Zenker’s diverticulum
Explanation:
The correct answer is
C. The clinical, radiologic, and manometric criteria of diffuse esophageal spasm are all described in the vignette. Achalasia (choice A) typically has clinical progression, as well as regurgitation of undigested food. In the manometric studies, there are no effective peristaltic contractions and there is increased resting pressure in the lower sphincter, which fails to relax during swallowing. The dysphagia of esophageal cancer (choice B) is typically progressive, from solids to liquids. The barium swallow would be diagnostic. Nutcracker esophagus (choice D) is very similar to diffuse esophageal spasm. However, on manometry there is a mean distal esophageal peristaltic amplitude of more than 180 mm Hg, including an elevated baseline pressure in the lower sphincter. Zenker’s diverticulum (choice E) produces regurgitation of undigested food and symptoms referable to the upper esophagus. The barium swallow would be diagnostic.
A 52-year-old woman has terminal cervical cancer with extensive pelvic invasion, and requires strong opiate analgesia to control severe pain. Intermittent nausea and vomiting have precluded the use of oral agents. She was on fentanyl patches but she developed allergic skin reactions to the adhesive and now requests to be switched to parenteral medication. Because of prior chemotherapy treatments she has no available venous access, but she is willing to have her family administer intramuscular injections. Assuming equianalgesic dosages, which of the following would be the most appropriate pharmacotherapy?A. Codeine
B. Hydromorphone (Dilaudid)
C. Meperidine (Demerol)
D. Methadone
E. Morphine sulfate
Explanation:
The correct answer is
D. Given the circumstances, the longest acting agent would be the best choice. Methadone lasts about 12 hours, compared with around 4 hours for all the others opiates listed (choices A, B, C, E).
9) A 43-year-old woman comes in because of a breast mass. Two days ago, she noticed a lump on self-examination. She has a 2-cm, firm, nontender mass in the left breast, which is movable from the chest wall, but not movable within the breast. She has no prior history of breast disease, but she is well read and well informed, and she specifically requests that a biopsy be done with a mammotome. Before proceeding, which of the following is the most appropriate initial step?
A. Discuss the surgical options in case cancer is found
B. Do a mammogram to ascertain whether biopsy is needed
C. Do a mammogram to find any other lesions that might also need to be addressed
D. First wait for two menstrual cycles to see whether there is spontaneous resolution.
E. Obtain a fine-needle aspirate and go no further if no malignant cells are found
Explanation:
The correct answer is
C. A breast lump in a 43-year-old needs to be biopsied, but before we undertake that aggressive step we must ascertain the full extent of her potential disease. Fingers can feel big lumps; x-ray films are needed to identify smaller ones. Discussing cancer therapy (choice A) is premature if we have not yet diagnosed cancer. We no longer live in the era of biopsy in the operating room, frozen section diagnosis, and surgery under the same anesthetic. The diagnosis should be established first, and then the options discussed. We need the mammogram to know what else may need to be biopsied, but not to tell us whether a biopsy is needed (choice B). We already have the indications for biopsy of the existing lesion, regardless of its appearance in a mammogram. Waiting for resolution (choice D) is okay for a woman with fibrocystic disease who gets lumps every month, but not for this woman who has never had breast disease before. Fine-needle aspiration (FNA) before a more invasive biopsy (choice E) is an acceptable choice, provided we understand that we will respond to a positive diagnosis established by cytology, but will not be dissuaded from getting a more complete sample if the FNA is negative. This option is unacceptable as worded.
10) A 35-year-old man falls on an outstretched hand and comes in complaining of wrist pain. He relates that he was not able to break the fall, and that the heel of his hand took the brunt of his full weight as it hit the pavement. On physical examination, he is distinctly tender to palpation over the anatomic snuff box. Anteroposterior and lateral x-rays are negative. Which of the following are the most likely diagnosis and most appropriate next step in management?
A. Carpal navicular fracture; thumb spica cast
B. De Quervain tenosynovitis; steroid injections
C. Displaced scaphoid fracture; open reduction and internal fixation
D. Ligamentous injury; Ace bandage and analgesics
E. No fracture; reassurance
Explanation:
The correct answer is
A. Nondisplaced fractures of the carpal navicular are notorious for not showing up on x-ray films at the time of injury. The mechanism of injury plus the physical findings described in this vignette are sufficient to make a presumptive diagnosis and to indicate the use of a cast. Tenosynovitis (choice B) is not the result of a direct blow, but it is seen in young mothers who carry the head of their babies with a hyperextended thumb and a flexed wrist. Displaced scaphoid fracture (choice C) would show up on x-ray films. The treatment for those fractures is indeed open reduction and internal fixation (they are notorious for non-healing), but the diagnosis is not correct in this option. Ligamentous injury (choice D) is often the assumption of those who are not aware of the peculiar nature of this injury. A similar mistake is made by those who assume that if an x-ray film appeared negative, there cannot be a fracture (choice E).
11) A 72-year-old woman has a red, swollen breast. She states that the condition has been present for at least several weeks, perhaps a month or two. She has no pain or fever. The skin over the area looks like orange peel. The area is not warm to the touch, but on physical examination there is a fullness to the entire breast, with no discrete mass. Which of the following is the most likely diagnosis?
A. Chronic cystic mastitis
B. Inflammatory cancer of the breast
C. Normal menopausal involutionary changes
D. Pyogenic breast abscess
E. Tuberculous or fungal breast abscess
Explanation:
The correct answer is
B. Age is your first tip-off: the older the patient is with any kind of breast problem, the more likely it is to be cancer. The description is that of inflammatory cancer, where the permeation of skin lymphatics has given the edema, redness, fullness, and orange peel appearance. The thick, tumor-laden skin actually masks the underlying mass, which is felt as “fullness” rather than a discreet lump. Chronic cystic mastitis (choice A) happens to younger women (aged 20-40) with recurrent pain linked to the menstrual cycle. Menopause (choice C) shrinks the breast and makes it more fat than stroma, but it does not make it red and swollen. Pyogenic abscess (choice D) happens almost exclusively to lactating women. At age 72, we know that is not happening. Tuberculosis or fungus (choice E) is our usual guess when an abscess is not hot and tender. However, apart from their rarity in the U.S., such thoughts here would detract from the compelling dictum that a red, swollen breast in an old woman is cancer until proven otherwise.
12) A 46-year-old woman, who had always been in good health, comes in because of the sudden onset of very severe back and leg pain that she experienced 2 hours ago when attempting to lift a heavy object. She says that she felt “a bolt of lightening” running down the back of her leg, and she still has very severe pain that prevents her from walking or moving. The pain is exacerbated by coughing, sneezing, or straining. She keeps the affected leg flexed; straight leg raising gives her excruciating pain. She has good sphincteric tone and intact sensation in the perineum. Once the diagnosis is confirmed with the appropriate studies, which of the following will be the most appropriate treatment?
A. Analgesics and bed rest for about 3 weeks
B. Appropriate antibiotics
C. Body cast for 3-6 months
D. Radiotherapy to the affected area
E. Surgical decompression
Explanation:
The correct answer is
A. The clinical features are those of a herniated lumbar disc. The diagnosis should be confirmed with an MRI, and then the patient should be treated conservatively with bed rest. Most patients get better with this simple approach. Giving antibiotics (choice B) assumes an infectious process. Infections can occur in the lumbar spine or the discs, but their symptoms do not start suddenly, like this vignette describes. A body cast (choice C) might be needed for fractures, scoliosis, or other spinal pathology, but casting is not needed for an extruded disc. Radiotherapy (choice D) assumes a neoplastic process. Although a weakened bone may indeed rupture suddenly, such patients are usually known to have had the kind of tumor that is likely to metastasize to bone (in women, breast cancer would lead the list), and would have been complaining of localized bony pain before the process gets to the point of fracture. Surgical decompression (choice E) would have been required if she had sphincteric deficits or perineal anesthesia.
13) A 56-year-old man develops slow, progressive paralysis of the facial nerve on one side. It took several weeks for the full-blown paralysis to become obvious, and it has been present now for 3 months. It affects both the forehead and the lower face. He has no pain anywhere, and no palpable masses by physical examination. Which of the following is the most likely diagnosis?
A. Bell’s palsy
B. Facial nerve tumor
C. Hemorrhagic stroke
D. Parotid gland cancer
E. Pleomorphic adenoma of the parotid gland
Explanation:
The correct answer is
B. Slowly developing paralysis on one side is suggestive of a tumor. Since there are no physical findings to place the tumor in the parotid gland, it must be impinging on the nerve itself at a more proximal location. Bell’s palsy (choice A) has sudden onset, rather than gradual development. Hemorrhagic stroke (choice C) would have occurred suddenly, with an excruciating headache. A parotid cancer (choice D) would have been palpable by physical examination and would have produced pain. Pleomorphic adenoma (choice E) would also have been palpable, and such tumors almost never produce facial nerve paralysis.
14) A young mother complains of pain along the radial side of the wrist and the first dorsal compartment. She relates that the pain is often caused by the position of wrist flexion and simultaneous thumb extension that she assumes to carry the head of her baby. On physical examination, the pain is reproduced by asking her to hold her thumb inside her closed fist, and then forcing the wrist into ulnar deviation. Which of the following is the most likely diagnosis?
A. Acute and chronic bursitis
B. Carpal tunnel syndrome
C. Hairline unrecognized fracture of the carpal navicular (scaphoid) bone
D. Palmar fascial contracture (Dupuytren’s contracture)
E. Tenosynovitis of the abductor or extensor tendons of the thumb (De Quervain’s tenosynovitis)
Explanation:
The correct answer is
E. The clinical presentation is classic for De Quervain’s tenosynovitis, including the positive Finkelstein sign (the pain reproduced by ulnar deviation to stretch the affected tendons). Bursitis (choice A) occurs where there are bursa; thus, the classic locations are places in which tendons or muscles pass over bony prominences. Carpal tunnel syndrome (choice B) affects young women, such as this patient, but the presentation is one of numbness along the innervation pattern of the entrapped median nerve. Fractures of the carpal navicular bone (choice C) often go unrecognized, but they occur when someone falls on an outstretched hand. The classic physical finding is pain with palpation over the anatomic snuff box. Dupuytren’s contracture (choice D) produces inability to fully open and extend the hand, and it typically happens to older men of Scandinavian descent.
15) A 44-year-old homeless woman presents to the emergency department because she is “bleeding from the breast.” Physical examination shows a huge, fungating, ulcerated mass that occupies the entire right breast and is firmly attached to the chest wall. The right axilla is full of hard masses that are not movable either. Core biopsies of the breast are read as highly undifferentiated infiltrating ductal carcinoma, and assay for estrogen and progesterone receptors are negative. Which of the following is the most appropriate next step in management?
A. Local wound care, but no specific antineoplastic therapy
B. Tamoxifen therapy
C. Radiation and chemotherapy
D. Palliative mastectomy
E. Radical mastectomy with extended lymph node dissection
Explanation:
The correct answer is
C. Although this is an impressive, very advanced cancer with a poor prognosis, it can be expected to shrink significantly with local radiation plus systemic chemotherapy. It may do so to the point at which a palliative mastectomy becomes technically feasible, something that cannot be done at this time. Taking care of the wound, and accepting defeat from the cancer (choice A), was the only available choice before chemotherapeutic agents and radiation therapy were developed. It would be entirely inappropriate at the present time. Tamoxifen (choice B) would be the weakest systemic weapon in this case. She is premenopausal and receptor negative. Tamoxifen alone would not shrink this tumor to any appreciable extent. Mastectomy, either simple (choice D) or radical (choice E), is not possible at this time. The description clearly depicts an inoperable tumor. We first need to make it operable.
16) A blond, blue-eyed, 69-year-old sailor has a non-healing, indolent, 1.5-cm ulcer on the lower lip, arising from the vermilion border. The ulcer has been present and growing for the past 8 months. He is a pipe smoker, but has no history of alcohol or drug abuse. Physical examination shows “weather-beaten” facial skin, but no other ulcers. There are no enlarged lymph nodes in his neck. Which of the following is the most likely diagnosis?
A. Adenocarcinoma
B. Basal cell carcinoma
C. Benign ulceration due to chronic trauma
D. Invasive malignant melanoma
E. Squamous cell carcinoma
Explanation:
The correct answer is
E. The location and history are classic for squamous cell carcinoma of the lower lip. The absence of metastatic nodes does not invalidate the diagnosis, as most cancers in this location do not metastasize until quite late. Adenocarcinoma (choice A) would be very rare in the lower lip. Basal cell carcinoma (choice B) favors the upper part of the face, above a horizontal line drawn across the mouth. Benign ulceration (choice C) is always a possibility, but it would be a terrible mistake to make such assumption. As pointed out before, this vignette is a “textbook case” for squamous cell carcinoma. Melanoma (choice D) is again very rare in this location. A history of a pigmented lesion that underwent changes in color, appearance, or diameter would have been suggestive.
17) A 54-year-old African American man, with a history of smoking and drinking, describes progressive dysphagia that began 3 months ago. He first noticed difficulty swallowing meat; it then progressed to other solid foods, then to soft foods, and now to liquids as well. He locates the place where the food “sticks” at the lower end of the sternum. He has lost 30 pounds. Which of the following is the most appropriate first step in diagnosis?
A. Barium swallow
B. Gastrografin swallow
C. Esophageal manometry
D. Esophageal pH monitoring
E. Esophagoscopy
Explanation:
The correct answer is
A. The clinical picture is that of a cancer of the esophagus, and given his race and history of smoking and drinking, it is probably a squamous cell carcinoma. The description of where the dysphagia is felt suggests a low location, but such subjective feelings lack precision. The tumor will eventually be seen and biopsied by endoscopy, but the endoscopist will first want to know the exact location of the tumor and the degree to which the lumen is occluded. Otherwise, there is a high risk of instrumental perforation of the esophagus. The best way to obtain that information is to do a barium swallow. Gastrografin (choice B) gives less detailed pictures and would be called for only if perforation was suspected. Manometry (choice C) would be called for if the history suggested a motility problem. Esophageal pH monitoring (choice D) would be the perfect test to document gastroesophageal reflux. Esophagoscopy (choice E) will indeed be done, but not until after the barium swallow.
18) A 39-year-old woman completed her last course of postoperative adjuvant chemotherapy for breast cancer 6 months ago. She now comes to the clinic complaining of constant back pain for about 3 weeks. She is tender to palpation over two well-circumscribed areas in the thoracic and lumbar spine. Which of the following is the most appropriate next step in management?
A. CT scan of the trunk
B. Needle biopsy of the tender spots
C. Radionuclide bone scan
D. Sonogram of the affected areas
E. X-ray films of the affected areas
Explanation:
The correct answer is
C. The most sensitive test to detect early bone metastasis is the radionuclide scan. In a woman who recently had cancer of the breast, we have to suspect bony metastasis when bone pain develops. CT scan (choice A) would be more expensive and less sensitive. Needle biopsy (choice B) is invasive and not the first thing to do. Sonogram (choice D) is superb for many other things, but not to detect early bone metastasis. X-ray films (choice E) will be done after the scan if the radionuclide “lights up.” The radionuclide scan is very sensitive, but not terribly specific. Once it lights up, we have to rule out other radiologically obvious bony problems that might have triggered the positive scan.
19) In preparation for an inguinal hernia repair, a 22-year-old man has a spinal anesthetic placed. The level of sensory block turns out to be much higher than had been planned, and shortly thereafter his blood pressure drops to 75/20 mm Hg. He looks warm and flushed, and his central venous pressure is near zero. Which of the following should be included in his therapy?
A. Diuretics and fluid restriction
B. Whole blood and clotting factors
C. Inotropic agents and cardiac assist pump
D. Vasoconstrictors and IV fluids
E. Vasodilators and IV fluids
Explanation:
The correct answer is
D. A high spinal anesthetic can produce vasomotor shock by inducing widespread vasodilation. Vasoconstrictors are the appropriate therapy, but since the capacity of the vascular tree is also increased under these circumstances, filling it up with additional volume is also helpful. Diuretics and fluid restriction (choice A) would compound the problem. The patient needs more fluid, not less. Whole blood and clotting factors (choice B) are not needed. The volume can be increased with cheaper and safer IV fluids until proper vascular tone is restored. Coagulation factors have not been lost. Inotropic agents and mechanical assistance to the circulation (choice C) are indicated in cardiogenic shock, which would be rare in a 22-year-old and would be identified, among other things, by a high central venous pressure. Vasodilators and fluids (choice E) are sometimes a good combination when hypovolemia plus high peripheral resistance deprive tissues of proper perfusion. In this case, however, vasodilation already exists (and is the genesis of the problem).
20) A 33-year-old woman is found to have a palpable thyroid nodule during a routine medical checkup. A sonogram confirms the presence of a solid, 1.5-cm nodule in the right lobe of the thyroid gland. Fine needle aspirate cytology (FNA) is reported as “follicular tumor, otherwise unspecified.” At surgery, a frozen section is read as follicular carcinoma. With the neck open, the surgeon can feel for enlarged jugular and peritracheal lymph nodes, and finds none. Which of the following is the most appropriate treatment?
A. Enucleation of the tumor
B. Right thyroid lobectomy
C. Total thyroidectomy
D. Total thyroidectomy plus postoperative radioactive iodine
E. Total thyroidectomy, radical neck dissection, and postoperative radioactive iodine
Explanation:
The correct answer is
D. Follicular cancers can metastasize by way of the blood stream to the liver, lung, brain, or bones. Because the tumor has rudimentary functional capability, it can be traced with and ablated by radioactive iodine; however, the tumor cannot compete successfully with normal thyroid tissue for the capture of iodine. After removal of the entire gland, the tumor becomes the most effective iodine trapper in the body. Enucleation (choice A) is never a good answer when dealing with cancer. Local recurrence would virtually be guaranteed. Lobectomy alone (choice B) would leave normal thyroid in place and thus prevent future use of radioactive iodine. Total thyroidectomy (choice C) is a correct, but incomplete, answer. Radical neck dissection (choice E) is not needed if there are no palpable nodes. Should they develop later, the procedure could be done then, or the nodes could be dealt with by means of radioactive iodine.
21) A 45-year-old woman, who wears high-heeled, pointed shoes, complains of pain in the forefoot after prolonged standing or walking. Occasionally, she also experiences numbness, a burning sensation, and tingling in the area. Physical examination shows no obvious deformities and a very tender spot in the third interspace, between the third and fourth toes. There is no redness, limitation of motion, or signs of inflammation. Which of the following is the most likely diagnosis?
A. Gout
B. Hallux rigidus
C. Metatarsophalangeal articulation pain
D. Morton’s neuroma
E. Plantar fasciitis
Explanation:
The correct answer is
D. The location and circumstances are classic for Morton’s neuroma, a benign neuroma of the third plantar interdigital nerve. Gout (choice A) happens to obese, elderly males, and redness and signs of inflammation in the affected joint are evident. Hallux rigidus (choice B) is osteoarthritis of the first metatarsophalangeal joint. There is deformity and limitation of motion. The joint is tender on physical examination. Metatarsophalangeal articulation pain (choice C) is likewise associated with misalignment of joint surfaces. There is pain when examining the joint, and there is no history of numbness, burning, or tingling. Plantar fasciitis (choice E) produces sharp pain on physical examination when pressing the plantar surface of the heel.
22) A 22-year-old gang member arrives in the emergency department with multiple gunshot wounds to the chest and abdomen. He has labored breathing and is cyanotic, diaphoretic, cold, and shivering. He is wide awake, and in a normal tone of voice he tells everyone that he is going to die. An initial survey reveals a blood pressure of 60/40 mm Hg. His pulse is 150/min and barely perceptible. He is in obvious respiratory distress and has big distended veins in his neck and forehead. His trachea is deviated to the left, and the right side of his chest is hyperresonant to percussion, with no breath sounds. Which of the following is the most appropriate initial step in management?
A. Emergency blood gases
B. Immediate chest x-ray films
C. Awake endotracheal intubation
D. A 16-gauge needle inserted in the second right intercostal space
E. Pericardiocentesis
Explanation:
The correct answer is
D. This patient obviously has a tension pneumothorax on the right. The pressure needs to be relieved immediately, which insertion of a needle will do. Then, a formal chest tube should be inserted. Blood gases (choice A) or chest x-ray films (choice B) are not needed to recognize the presence of a tension pneumothorax. These two studies will soon be done in this patient, but not before action is taken to save his life by prompt decompression of the tension pneumothorax. A patient who is awake and alert and speaking with a normal tone of voice has a patent airway. At this moment, he does not need endotracheal intubation (choice C), although given his multiple injuries, he will probably end up having surgery and being intubated for that anesthetic. Pericardiocentesis (choice E) assumes our first clinical diagnosis is pericardial tamponade. If he were still in shock and still had big distended veins after his pleural space had been decompressed, we might think that he also has a pericardial tamponade in addition to the tension pneumothorax. In fact, as the most pressing problems are resolved, we might uncover other reasons for his state of shock, such as internal bleeding. Right now, however, what is crying out for help is his right pleural space.
23) A 66-year-old woman picks up a bag of groceries out of the supermarket cart to place it in the trunk of her car. As she does so, she feels sharp, sudden pain in the middle of her arm, and her humerus suddenly breaks. She arrives at the emergency department cradling her arm; the deformity leaves no doubt that the bone is broken. Which of the following is the most likely reason for the fracture?
A. Bony metastasis to the humerus from breast cancer
B. Osteitis fibrosa cystica from parathyroid disease
C. Osteomalacia from nutritional deficiency
D. Osteoporosis
E. Primary malignant bone tumor
Explanation:
The correct answer is
A. A fracture from such trivial strain signifies a very weakened bone. In this age and gender, the most likely cause would be a lytic lesion from metastatic breast cancer. In a man, we would have suspected metastatic lung cancer (not prostate, because prostatic metastases are blastic rather than lytic). The bony reabsorption of parathyroid disease (choice B) is mostly seen as cystic lesions in the bones of the hand. In very advanced cases, bones may be deformable, but parathyroid hormone does not weaken major bones to the point at which they break. Osteomalacia (choice C), and its counterpart in children, rickets, deforms bones, but they would not break as described here. Osteoporosis (choice D) is indeed likely to be present in this woman. However, even with advanced osteoporosis, the only spontaneous fractures seen are compression fractures of vertebral bodies. Osteoporotic bones break easily, but there has to be more trauma than lifting a bag of groceries. Primary malignant bone tumors (choice E) occur in young people. They do not occur at this age.
24) A 62-year-old man has had gastroesophageal reflux disease diagnosed by pH monitoring, and present for several years. He has been less than totally compliant with medical management, which he follows when the pain is bad, but discontinues when he feels better. Endoscopy and biopsies show severe peptic esophagitis, with Barrett’s esophagus and early dysplastic changes, but no overt carcinoma. Additional tests show good esophageal motility, with low pressure in the lower esophageal sphincter and normal gastric emptying. Which of the following is the most appropriate treatment at this time?
A. Heller myotomy of the lower esophageal sphincter
B. Laparoscopic Nissen fundoplication
C. Transhiatal total esophagectomy
D. Transthoracic resection of the lower esophagus
E. Vagotomy, pyloroplasty, and fundic gastric wrap
Explanation:
The correct answer is
B. This man has indications for surgical intervention, but all he needs is an antireflux operation. By far the most commonly used procedure is a laparoscopic Nissen fundoplication. Heller myotomy (choice A) is used for achalasia. Here it would do the exact opposite of what is needed. Transhiatal total esophagectomy (choice C) is the most commonly used operation for esophageal cancer. It is only palliative, since it cannot provide a true “cancer operation” with wide dissection, but esophageal cancer is rarely amenable to true curative resection when it becomes symptomatic. Although this man could develop cancer if he is not treated, he does not have advanced cancer at this time. Transthoracic resection of the lower esophagus (choice D) would be the procedure if a very early cancer were to develop at the esophagogastric junction. If this man did not choose to have the antireflux surgery now, but he remained under close surveillance, he might get to the point where he became a candidate for this option. Acid reduction (choice E) is not part of the standard surgical treatment for gastroesophageal reflux. We can control acid medically. If we have to operate, we do it to provide a good one-way valve when the native sphincter no longer works.
25) A 14-year-old boy slides down a banister and crashes into a large ornamental knob at its base, thereby injuring his scrotal contents. He presents in the emergency department with acute testicular pain and a scrotal hematoma the size of a grapefruit. He is able to void normally, and his urine does not contain blood. A rectal examination is unremarkable. Findings from which of the following tests will most likely determine further therapy?
A. Aspiration of scrotal contents
B. Retrograde cystogram
C. Retrograde urethrogram
D. Scrotal sonogram
E. Scrotal surgical exploration
Explanation:
The correct answer is
D. The clinical findings do not suggest urethral injury, but testicular fracture is a potential injury that would require surgical intervention. Sonogram would be diagnostic. Aspiration (choice A) is not a good idea. We already know that blood is present, and putting needles into it would invite bacterial contamination. If the testicle is intact, the hematoma will resolve spontaneously. Neither the bladder (choice B) nor the urethra (choice C) need to be checked when the urine has no blood, the patient can void normally, and the rectal examination is unremarkable. Surgical exploration (choice E) is not indicated unless a diagnosis of testicular rupture has been made.
26) A 40-year-old, obese, white woman, mother of five children, gives a history of repeated episodes of right upper quadrant abdominal pain. The pain is brought about by the ingestion of fatty foods and is relieved by the administration of anticholinergic medications. The pain is colicky, radiates to the right shoulder and around to the back, and is accompanied by nausea and occasional vomiting. The patient has no pain at this time, but is anxious to avoid further episodes. She is afebrile, and physical examination is unremarkable. Which of the following is the most appropriate next step in management?
A. Sonogram of the biliary tract and gallbladder
B. Upper gastrointestinal series with barium
C. Antibiotics, IV fluids, and nothing by mouth
D. Endoscopic retrograde cholangiopancreatogram (ERCP)
E. Exploratory surgery
Explanation:
The correct answer is
A. The clinical description is classic for biliary colic, due to gallstones that are intermittently impacted at the cystic duct. The diagnostic study of choice to confirm the presence of gallstones is a sonogram. An upper gastrointestinal series (choice B) will miss the diagnosis. This woman does not have a problem in her stomach or duodenum. She has to be suspected of having gallstones, and the study has to target that area. Antibiotics and IV fluids (choice C) are required to “cool down” an episode of acute cholecystitis. However, this woman does not have fever, leukocytosis, and a tender right upper quadrant. She does not have acute cholecystitis. Endoscopic retrograde cholangiopancreatogram (ERCP) (choice D) would be an expensive, invasive, and totally unjustifiable way to take a look at the gallbladder. Exploratory surgery (choice E) would be even worse. This woman will need surgery, but it should be directed at the gallbladder and done laparoscopically as an elective procedure (i.e., at a convenient time) after a diagnosis has been confirmed.
27) A 29-year-old man presents with a 2-day history of severe left-sided scrotal pain and swelling. He is sexually active and has had “many” sexual partners. His temperature is 38.2 C (100.8 F), blood pressure is 120/70 mm Hg, and pulse is 80/min. Examination shows unilateral intrascrotal tenderness and swelling. Testicular support makes the pain less intense. Which of the following is the most likely diagnosis?
A. Epididymitis
B. Prostatitis
C. Testicular torsion
D. Urethritis
E. Varicocele
Explanation:
The correct answer is
A. This patient has epididymitis, most likely due to Chlamydia trachomatis. Epididymitis refers to inflammation of the epididymitis, which leads to unilateral intrascrotal pain, swelling, and fever. Testicular support usually relieves the pain to some extent. Asymptomatic urethritis can be associated with epididymitis due to
C. trachomatis or Neisseria gonorrhoeae. Urinalysis may reveal pyuria. Urethral culture, urine polymerase chain reaction (PCR) or ligase chain reaction (LCR) can confirm the diagnosis. Treatment is with azithromycin, doxycycline or tetracycline. The sexual partner should be treated to avoid reinfection. Prostatitis (choice B) is the inflammation of the prostate, which often presents with perianal and low back pain, urinary frequency, urgency, and pain during urination. Treatment is with antibiotics. Testicular torsion (choice C) is a surgical emergency, which is caused by twisting of the spermatic cord and vascular compromise. It typically occurs in young adult males, who present with acute unilateral testicular pain and normal urinalysis results. Testicular support does not relieve the pain. Urethritis (choice D) is an infection most often caused by Chlamydia or N. gonorrhoeae, and presents with a urethral discharge. The discharge is mucoid in chlamydial infection and purulent in gonorrhea. The treatment is ceftriaxone and doxycycline. Sexual partners should be treated. Varicoceles (choice E) are a collection of veins that feel like a “bag of worms”. Surgery is indicated if there is infertility or pain. They are more common on the left side.
28) A pedestrian is hit by a car. The paramedics report that he was unconscious at the site, and he arrives at the emergency department in coma, strapped to a head board with sandbags on either side of his head. Initial survey shows stable vital signs, and his pupils are of equal size and reactive to light. He is rapidly intubated by the nasotracheal route over a flexible bronchoscope and then sent for CT scans of the head. As he is being positioned on the table, it is noted that there is a sizable hematoma behind his right ear and that clear fluid is dripping from the ear canal. Which of the following is most advisable, considering this new finding?
A. Extend the CT scan to include his neck
B. Do an MRI instead of a CT scan
C. Start antibiotics
D. Inject high-dose corticosteroids
E. Plan an emergency craniotomy
Explanation:
The correct answer is
A. The clinical findings are indicative of a fracture of the base of the skull, and thus he has sustained very significant trauma to the head. The integrity of the cervical spine has to be ascertained, and the CT that he is already going to have can be extended to include that area. MRI (choice B) has no role in the acute trauma situation. If we were looking for a brain tumor, at leisure, an MRI would indeed be better than a CT-but not in this setting. Antibiotics (choice C) have proven to be of no value in base of the skull fractures. Corticosteroids (choice D) are being used in patients with spinal cord injury, but we have not yet diagnosed the presence of such an injury. Emergency craniotomy (choice E) is not needed to deal with a basilar skull fracture. He would need one if his CT scan showed an intracranial hematoma displacing the midline structures. He might need one later if the leak of CSF persists, but he does not need one now.
29) During a campaign appearance, a political candidate is shot point blank in the right chest with a .22 caliber revolver. The entrance wound is well above the nipple line, just under the third rib, at the level of the anterior axillary line. His motorcade brings him to the emergency department, but he makes it a point to walk in, holding his right chest with a bloody hand and waving for the news media. A chest x-ray shows a hemothorax on the right, and the bullet is seen to be embedded in the right paraspinous muscles. A chest tube is placed in the right pleural cavity, and 650 mL blood is recovered. Over the ensuing 4 hours, he continues to drain between 250 and 350 mL blood per hour. Which of the following is the most appropriate next step in management?
A. Continued observation and appropriate blood replacement
B. A second chest tube in a better position to drain the blood
C. Thoracotomy and ligation of bleeding vessels
D. Thoracotomy, ligation of bleeding vessels, and removal of the bullet
E. Thoracotomy and pneumonectomy
Explanation:
The correct answer is
C. Although most penetrating wounds of the chest that produce hemothorax require no surgery, there are cases in which systemic vessels (almost invariably intercostals), rather than the injured lung (which has low pressure circulation) are the source of bleeding. In those cases, surgical hemostasis is required. They are identified by the magnitude of the blood loss. Typical criteria suggest the need for thoracotomy if the initial blood recovery exceeds 1000 mL, or if subsequent drainage adds up to 600 mL or more, over the ensuing 6 hours. Continued observation (choice A) would be inappropriate given the rate of 250-350 mL of blood loss per hour. The problem is not lack of drainage; thus, another tube (choice B) would not resolve the problem. Although choice D is almost identical to choice C, it adds a medically unnecessary step: the bullet does not have to be removed. Additional operative time and operative dissection are not justified if the bullet is not pressing on some vital structure. If it happens to be lying there, just waiting to be plucked, we would of course take it. Pneumonectomy (choice E) targets the wrong organ. Bleeding from the lung is usually self-limiting. Bleeding that requires surgery is usually from systemic vessels, most commonly the intercostals.
30) During the performance of a supraclavicular node biopsy under local anesthesia, a hissing sound is suddenly heard, and the patient suddenly dies. At the time of the catastrophic event, the target node was under traction, and the final cut was being made blindly behind it to free it up completely. The patient, an otherwise healthy 24-year-old man, was inhaling at that moment. Which of the following most likely caused this patient’s death?
A. Arterial injury with air embolization
B. Major vein injury with air embolism
C. Sudden pneumothorax with lung collapse
D. Sympathetic discharge
E. Tracheal injury
Explanation:
The correct answer is
B. Major veins at the base of the neck have negative pressure during inspiration and, if injured at that moment, will suck air rather than bleed. The air embolism then leads to sudden death. Arterial injury (choice A) would have led to massive bleeding but not to sudden death. Pneumothorax (choice C) can indeed happen when surgery is being done in the supraclavicular area, and a sucking sound might even be heard. However, sudden lung collapse in a young, healthy person leads to dyspnea, not to sudden death. Sympathetic discharge (choice D) would be hard to produce while pulling and dissecting a node. If it were done, however, there would be vasoconstriction, tachycardia, perspiration, and hypertension, rather than sudden death. Had the trachea been injured (choice E), essentially nothing would have happened at the time.
31) An elderly woman with osteoporosis falls on her outstretched hand. She comes in with a deformed and painful wrist that looks like a dinner fork. X-ray films show a dorsally displaced, dorsally angulated fracture of the distal radius. There is also an associated fracture of the ulnar styloid. A neurologic examination is normal. Which of the following is the most appropriate management?
A. Closed reduction and short arm cast
B. Closed reduction and long arm cast
C. Skeletal traction
D. Intramedullary rod
E. Open reduction and internal fixation
Explanation:
The correct answer is
B. This is the famous Colles fracture, which typically can be reduced well with closed manipulation. Casting should immobilize both the wrist and the elbow, thus a long arm cast is needed. A short arm cast (choice A) would not immobilize the elbow. Skeletal traction (choice C) could correct the deformity, but at the cost of limiting future function of the hand. An intramedullary rod (choice D) is usually reserved for fractures of the shaft of long bones, like the femur. Open reduction and internal fixation (choice E) could indeed provide a very nice result, but it would be an unnecessarily expensive and intrusive way to do it.
32) A 43-year-old man develops excruciating abdominal pain at 8:23 PM (he looked at his watch when the pain “hit him”). When seen in the emergency department about 30 minutes later, he has a rigid abdomen, lies motionless on the examination table, has no bowel sounds, and is obviously in great pain, which he describes as constant and encompassing the entire abdomen. There is very severe pain when deep palpation of the abdomen is attempted in any of the four quadrants. However, the examining hand cannot make much of an indentation because of the impressive muscle guarding. When the attempt is aborted, he manifests severe rebound tenderness. X-ray films show free air under both diaphragms. Which of the following does this man most likely have?
A. Acute abdomen, the nature of which cannot yet be defined
B. Acute inflammatory process affecting an intra-abdominal viscera
C. Acute obstruction of an intra-abdominal viscera
D. Ischemic process affecting intra-abdominal organs
E. Perforation of the gastrointestinal tract
Explanation:
The correct answer is
E. There is no doubt that this patient has an acute abdomen, but we can tell more than that. The sudden onset, generalized extent, and silent abdomen in a man who does not want to move suggests a perforation. In addition, the presence of free air in the peritoneal cavity pinpoints the gastrointestinal tract as the source. We cannot tell whether he perforated a peptic ulcer, blew out a sigmoid diverticulum, or had his bowel perforated by a chicken bone, but there is a hole in his gastrointestinal tract. Choice A underestimates our diagnostic ability. An inflammatory process (choice B) would have gradual onset and would be localized to the area of the inflamed viscera. Obstruction (choice C) has sudden onset, but it leads to colicky pain. The patient would be thrashing about looking for a position of comfort, and would still have bowel sounds and not have free air. Ischemia (choice D) is a better bet in an older person. If it were to lead to necrosis and perforation, the latter would not be evident 30 minutes after the trouble began.
33) On the 5th postoperative day after abdominal surgery, a patient has been draining copious amounts of clear pink fluid from his midline laparotomy wound. A medical student removes the dressing, confirms that it is soaked, and sees a normal-appearing fresh wound with a row of skin staples in place. The student asks the patient to sit up so he can get out of bed and be helped to the treatment room for a more thorough examination. When the patient complies, the wound opens widely, and a handful of small bowel suddenly rushes out. Which of the following is the most appropriate management at this time?
A. Cover the bowel with dry sterile dressings and schedule urgent surgical closure
B. Cover the bowel with sterile dressings soaked in warm saline and rush the patient to the operating room
C. Irrigate the bowel with cold antiseptic solutions while awaiting urgent surgical closure
D. Take the patient to the treatment room and suture the skin edges together
E. Wearing sterile gloves, push the bowel back in and tape the wound securely
Explanation:
The correct answer is
B. Until the patient attempted to get out of bed, he had a wound dehiscence that could have been handled by taping the wound securely. Once the bowel came out, the problem became an evisceration. Immediate surgical repair is mandatory. While setting it up, the bowel must be protected from drying out, and the patient must be protected from significant heat loss. Thus, the key is warm and moist dressings. Dry dressings (choice A) would prevent further contamination but would fail in the key elements of “warm and moist.” Cold antiseptic solutions (choice C) would irritate the bowel and contribute to hypothermia. Once an evisceration has occurred, the entire abdominal wall has to be surgically closed. Suturing the skin edges in an inadequate facility (choice D) or resorting to tape (choice E) would not suffice.
34) A 77-year-old man becomes “senile” over a period of 3 or 4 weeks. He used to be active and managed all of his financial affairs. Now, he stares at the wall, barely talks, and sleeps most of the day. His daughter recalls that he fell from a horse about a week before the mental changes began. Which of the following would a CT scan of his head most likely show?
A. Chronic epidural hematoma
B. Chronic subdural hematoma
C. Diffuse intracerebral bleeding
D. Frontal lobe infarction
E. Generalized, severe brain atrophy
Explanation:
The correct answer is
B. People who are very old or alcoholic have smaller brains in a skull that has not changed in size; thus, very minimal trauma can make the brain “rattle around” and tear a venous sinus, from which a subdural hematoma very slowly forms. Senility does not occur in a 3-week period. Such marked changes in someone with recent trauma should trigger a search for chronic subdural hematoma. Epidural hematomas (choice A) are typically acute, from a tear of the middle meningeal artery following trauma that fractures the skull. Diffuse intracerebral bleeding (choice C) would occur with very severe trauma and would give more acute symptoms. The frontal lobe (choice D) is responsible for judgment and social graces, but not for financial acumen and level of activity-the functions that this man used to have and lost over a short period of time. Brain atrophy (choice E) is indeed present in the very old or the alcoholic. That is what makes them prone to develop chronic subdural hematomas. But, brain atrophy alone would not explain the mental changes that this man developed over a few weeks.
35) A man who weighs 65 kg sustains second and third degree burns over both of his lower extremities when his pants catch on fire. When examined shortly thereafter, it is ascertained that virtually all of the skin from both groins to the tip of the toes, front and back, has been burned. According to the modified Parkland formula, which of the following is the approximate total amount of IV fluid that he can be expected to require during the first 24 hours post-burn?
A. 3460 mL
B. 4960 mL
C. 6760 mL
D. 8160 mL
E. 11,360 mL
Explanation:
The correct answer is
E. The modified Parkland formula calls for 4 mL of Ringer’s lactate per kilogram of body weight, times the percentage of the body surface that has been burned; plus an additional 2000 mL of dextrose 5% in water to cover maintenance fluid needs. In the “rule of nines,” each lower extremity represents 18% of the body surface. Thus, this patient has sustained a 36% body burn: 4 × 65 × 36 = 9360, plus 2000 = 11,360 None of the other options provide enough fluid, although in the real world the formula calculations are used only to help determine a “ballpark figure” and a rate of initial infusion. Once fluid is going in, the fine tuning is done on the basis of hourly urinary output and central venous pressure.
36) A 49-year-old woman has a firm, 2-cm mass in the right breast that has been present for 3 months. Mammogram has been read as “cannot rule out cancer,” but it cannot diagnose cancer either. A fine-needle aspiration of the mass (FNA) and cytology do not identify any malignant cells. Which of the following is the most appropriate next step in management?
A. Reassurance and reappointment in a year
B. Repeat mammogram and FNA in 1 month
C. Core or incisional biopsies
D. Lumpectomy and axillary dissection
E. Modified radical mastectomy
Explanation:
The correct answer is
C. Negative findings do not have the same diagnostic value that positive findings have. If this had been a 19-year-old woman suspected of having a fibroadenoma, one would have been satisfied with negative imaging studies (in that age, a sonogram) or the negative FN
A. But, at age 49, the risk of cancer is much higher. Given negative findings in the least invasive studies, one would feel compelled to move to more aggressive ways to obtain better tissue sampling. Obviously, reassurance (choice A) is not justified yet, and waiting a whole year with what may be a cancer would be malpractice. Repeating the same studies in a month (choice B) leaves you with the quandary of what to do if they are negative again. No, you need more tissue for the pathologist right now. Lumpectomy and axillary dissection (choice D) is too much to do before the diagnosis has been established. Lumpectomy alone might have been okay. An excisional biopsy could indeed be justified under the circumstances, and a lumpectomy is not much more than a big excisional biopsy. But, messing with the axilla should not happen before we know it is cancer. Mastectomy (choice E) is even less acceptable. Patients are grateful when a cancer is ruled out by procedures that they do not perceive as mutilating. But, when surgery leaves them deformed, the “good news” that there was no cancer may lead them to call their lawyer.
37) A young mother is at the pediatrician’s office for a routine well-baby visit for her 18-month-old son. It is immediately noticed that one of the baby’s pupils is white, while the other one is black. When asked about it, the mother relates that she saw that curious situation for the first time 1 week ago, but since the baby was otherwise asymptomatic, she did not think it merited special attention. Which of the following is the most appropriate course of action?
A. Do nothing, this is a normal anatomic variant
B. Inquire if the father is an albino, and do appropriate genetic counseling
C. Seek an ophthalmologic consultation for suspected congenital cataract
D. Seek an emergency ophthalmologic consultation for possible retinoblastoma
E. Treat the child with antibacterial eye drops and re-check in 2 weeks
Explanation:
The correct answer is
D. A newly developed white pupil in a child raises the possibility of retinoblastoma. This tumor is so deadly that immediate diagnosis and treatment are imperative. Ignoring the finding (choice A) could prove to be lethal, and the same can be said for any delays caused by pursuing bizarre considerations, such as looking for albinos in the family (choice B) or treating for an eye infection that is not there (choice E). It could be argued that if an ophthalmologic consultation is obtained, even if it is for a wrong diagnosis (choice C), the true nature of the problem will eventually be recognized. But an appointment to check for cataracts (which would have been present since birth) will not be made with the same urgency that the situation requires.
38) A 23-year-old man known to have neurofibromatosis, type 1 (von Recklinghausen’s disease), presents with a left lower quadrant abdominal mass and signs of neurologic deficits in his left leg. In the ensuing workup, it is determined that he has higher than normal values of catabolites of epinephrine and norepinephrine in a 24-hour urinary collection. He is currently normotensive. Before invasive steps are taken to biopsy and eventually remove his left lower quadrant abdominal mass, which of the following is the most appropriate next step in management?
A. CT scan of the head looking for meningiomas
B. MRI of his adrenal glands
C. MRI of the acoustic nerves
D. Radionuclide scans from the neck to the pelvis looking for extra-adrenal pheochromocytomas
E. Radiation therapy to the left lower quadrant abdominal mass
Explanation:
The correct answer is
B. The concern is that even though he is now normotensive, invasive steps might trigger a hypertensive crisis from the previously undiagnosed pheochromocytoma that he probably has. The presence of catabolites from epinephrine indicates that the tumor is in the adrenal glands, and not at an extra-adrenal site. Thus, the diagnosis of the pheochromocytoma can best be confirmed by MRI of the adrenals. Meningiomas (choice A) and acoustic nerve tumors (choice C) occur in type 2 neurofibromatosis, not in type 1. Looking for pheochromocytomas outside of the adrenal glands (choice D) would have been a good idea if only elevated catabolites of norepinephrine had been detected. The presence of high levels of epinephrine catabolites implicates the adrenal glands. Radiation therapy (choice E) is a bad idea. Benign neurofibromas can be stimulated by radiation to undergo malignant transformation.
39) A car is involved in a head-on collision. The driver, who is sober and wearing his seat belt, explains that he clearly saw his drunk, unrestrained front seat passenger hit the windshield with his face and the dashboard with his knees. Examination of the passenger indeed shows multiple facial lacerations, but because of his intoxication he cannot explain where else he might be hurting. He is neurologically intact, and his cervical spine x-ray films are normal. Additional injury, representing a potential orthopedic emergency, is not obvious but is suspected. Therefore, an x-ray film of which of the following areas should most likely be obtained?
A. Both patellas
B. Both hips
C. The jaw
D. The lumbar spine
E. The skull
Explanation:
The correct answer is
B. When hitting the knees against the dashboard, the femurs can be driven backward and out of the acetabulum, resulting in posterior dislocation of the hips. Because of the tenuous blood supply of the femoral heads, such injury must be promptly recognized and treated. Both patellas (choice A) and the jaw (choice C) could indeed be fractured, but such fractures would be easily recognized clinically. If they were not identified until the next day, no damage would be incurred. The lumbar spine (choice D) should always be thought of when someone falls from a height and lands on his feet, but it is not a likely hidden injury in this setting. Skull x-ray films (choice E) have gone out of favor as a way to assess head injury. The main issue in head injuries is intracranial bleeding, and the study to show it is the CT scan.
40) During a hunting trip, a young man is bitten by a coyote. The animal is captured and brought to the authorities alive. Which of the following is the most important criterion to determine the patient’s need for rabies prophylaxis?
A. The patient’s history of previous immunizations
B. The patient’s clinical course over the next few weeks
C. Observing the animal’s behavior over the next few days
D. Killing the animal and examining the brain
E. The events that took place have already established the need to proceed with rabies immunization
Explanation:
The correct answer is
D. Examination of the animal’s brain for signs of rabies will determine whether the painful and risky process of rabies passive and active immunization is required. History of previous immunizations (choice A) is used to determine what to do for tetanus prophylaxis, but it has no application for rabies, because virtually no one has ever received such immunization in the past. Waiting for signs of rabies to appear in the patient (choice B) would be a death sentence. We can prevent rabies, but once established we cannot cure it. Observation of the animal’s behavior (choice C) is applicable when dealing with provoked bites by domestic pets. The behavior of a wild animal gives no clues to the presence or absence of rabies. If the animal had escaped, choice E would have been correct.
41) A 62-year-old woman had an abdominal hysterectomy and salpingo-oophorectomy 3 days ago. She had an indwelling bladder catheter during the procedure, which was removed in the recovery room. She has been voiding at will since then. She also had compression pneumatic stockings on both lower extremities during the operation. She began ambulation on the 1st postoperative day, and has been as active as possible under the circumstances, including faithful adherence to a prescribed program of incentive spirometry. On the evening of the 3rd postoperative day, she spikes a fever, with a temperature to 39.4 C (103 F). Which of the following is the most likely source of the fever?
A. Atelectasis
B. Deep thrombophlebitis
C. Intra-abdominal abscess
D. Urinary tract infection
E. Wound infection
Explanation:
The correct answer is
D. The timing is our major clue. Fever on postoperative day 3 is usually from the urinary tract. The circumstances are also there: she had instrumentation of her urinary tract during the procedure. Atelectasis (choice A) is usually seen on day 1, and she is doing everything possible to avoid this complication. Deep thrombophlebitis (choice B) could show up this early, but is more likely to do so 5-7 days after surgery. Furthermore, the patient had adequate protection during surgery and has been moving around since early on. Intra-abdominal abscess (choice C) would need at least 7-10 days to develop. This is too early for that. Wound infection (choice E) is likewise a later complication, typically seen about a week after the operation.
42) A 76-year-old man is undergoing an abdominoperineal resection for rectal cancer. During the surgery, unexpected severe bleeding is encountered, and the patient is hypotensive on and off for almost an hour. The anesthesiologist notes ST depression and T-wave flattening on the ECG monitor. Which of the following is the most likely diagnosis and the expected mortality?
A. Intraoperative air embolus, 100%
B. Myocardial infarction, 5% to 10%
C. Myocardial infarction, 50% to 90%
D. Pulmonary embolus, 5% to 10%
E. Pulmonary embolus, 50% to 90%
Explanation:
The correct answer is
C. Intraoperative myocardial infarction is mostly seen in elderly men, and the most common triggering event is prolonged hypotension. Furthermore, the mortality greatly surpasses that of a myocardial infarction de novo (ie, unrelated to surgery), reaching the levels quoted. Air embolism (choice A) can happen when big veins are open, allowing air to be sucked in; however, the location of the open veins is typically the upper chest or lower neck. The patient dies while undergoing a procedure under local anesthesia, breathing spontaneously rather than having air blown into his lungs. Choice B correctly identifies the problem, but assigns it a low mortality more typical of infarcts that do not happen during surgery. Pulmonary emboli (choices D and E) are not usually seen during surgery; they typically occur 5-7 days later.
43) A 44-year-old woman has a palpable nodule in the right lobe of her thyroid gland. The nodule measures 2 cm and is firm. The rest of the thyroid gland cannot be felt and is not tender. She also describes losing weight in spite of a ravenous appetite, palpitations, and heat intolerance. She is thin, fidgety, and constantly moving, with moist skin and a pulse of 105/min. She has no exophthalmos or pretibial edema. Her TSH is reported as much lower than normal, and she has elevated levels of free T4. Which of the following is the most appropriate next step in diagnosis?
A. Exploratory neck surgery
B. MRI of the pituitary gland
C. Needle core biopsy of the thyroid mass
D. Radionuclide thyroid scan
E. Serum levels of T3
Explanation:
The correct answer is
D. There is no question, both clinically and by laboratory, that the patient is hyperthyroid. She has no clinical signs of acute thyroiditis, and none of the other findings seen in Graves disease; however, she has a thyroid nodule, which raises the possibility of a hyperfunctioning adenoma (a “hot” adenoma). If indeed she does, the scan will show that the nodule traps all the iodine, with suppression of the rest of the gland. Exploratory neck surgery (choice A) would be premature without first defining the source of the hyperfunction. The pituitary (choice B) is not at fault if the TSH is low. Hyperthyroidism and thyroid cancer rarely coexist. Should one wish to exclude the latter, fine-needle aspiration would be the first test. Percutaneous core biopsy of thyroid nodules (choice C) is not favored in this country. Levels of T3 (choice E) are needed only when clinical hyperthyroidism and low TSH are found to exist in the presence of normal levels of free T4.
44) A 66-year-old man presents with progressive jaundice, which he first noticed 6 weeks ago. He has a total bilirubin of 22 mg/dL, with a direct (conjugated) bilirubin of 16 mg/dL. His transaminases are minimally elevated, whereas his alkaline phosphatase is about six times the upper limit of normal. A sonogram shows dilated intrahepatic ducts, dilated extrahepatic ducts, and a very distended, thin-walled gallbladder without stones. Which of the following is the most appropriate next step in diagnosis?
A. CT scan of the upper abdomen
B. Endoscopic retrograde cholangiopancreatography (ERCP)
C. Exploratory laparotomy
D. Percutaneous transhepatic cholangiogram (PTC)
E. Serologies to define the type of hepatitis
Explanation:
The correct answer is
A. Obstructive jaundice is evident by the high alkaline phosphatase and the dilated biliary ducts. Malignancy is suggested by the dilated, thin-walled gallbladder without stones. If there is a cancer of the head of the pancreas, CT has a good chance of showing it in a noninvasive manner. Endoscopic retrograde cholangiopancreatography (ERCP) (choice B) or percutaneous transhepatic cholangiogram (PTC) (choice D) would be the next step if the CT scan were negative. A smaller tumor at the ampulla, the common duct itself, or even the head of the pancreas, could escape detection by the CT and necessitate a more invasive test to show up. Either of these could be used, although ERCP is favored by most. Exploratory laparotomy (choice C) would be premature at this point. Serologies (choice E) would have been called for if he had very high transaminases, normal or near normal alkaline phosphatase, and an unremarkable sonogram.
45) An older, overweight man complains of disabling, sharp heel pain every time his foot strikes the ground. The pain is worse in the mornings, preventing him from putting any weight on the heel. X-ray films show a bony spur matching the location of his pain, and physical examination shows exquisite tenderness to direct palpation right over that heel spur. Furthermore, when the ankle is dorsiflexed, the entire inner border of the fascia is tender to palpation. Which of the following is the most likely diagnosis?
A. Epiphysitis of the calcaneus
B. Fracture of the posterolateral talar tubercle
C. Plantar fasciitis
D. Posterior Achilles tendon bursitis
E. Posterior tibial nerve neuralgia
Explanation:
The correct answer is
C. All the details are in the vignette, including the association with a heel spur that in the past led many of these patients to undergo unnecessary surgery to remove the spur. The spur is caused by the pull of the fascia and is not the cause of the plantar fasciitis. Epiphysitis of the calcaneus (choice A) affects children, and the pain occurs along the sides of the heel where the heel growth centers are located. Fracture of the posterolateral talar tubercle (choice B) occurs from a sudden jump on the ball of the foot, and the pain and swelling are behind the ankle. Posterior Achilles tendon bursitis (choice D) occurs mostly in young women, and an erythematous, indurated, tender area is present at the posterosuperior aspect of the heel. Posterior tibial nerve neuralgia (choice E) is the foot’s equivalent of the carpal tunnel syndrome, with the pain often extending to the toes, and tingling being produced by tapping the nerve.
46) An elderly man is involved in a rear end automobile collision in which he hyperextends his neck. He develops paralysis and burning pain of both upper extremities, while maintaining good motor function in his legs. Which of the following is the most likely diagnosis?
A. Anterior cord syndrome
B. Central cord syndrome
C. Posterior cord syndrome
D. Reflex sympathetic dystrophy
E. Spinal cord hemisection
Explanation:
The correct answer is
B. The mechanism of injury (hyperextension) and the relative sparing of the lower extremities in the presence of upper extremity deficits are classic for central cord syndrome. In anterior cord syndrome (choice A), all functions are lost, except for positional and vibratory sense. Those injuries occur with blowout of the vertebral bodies. Posterior cord syndrome (choice C) is quite rare, and it would show loss of positional and vibratory sense. Reflex sympathetic dystrophy (choice D) produces agonizing burning pain (thus, it is a good distracter for this vignette), but it typically follows crushing injuries of the affected extremity and does not affect motion. Hemisection of the spinal cord (choice E) produces loss of one set of functions on one side, and a different set of functions on the other side. In addition, it follows a clear-cut penetrating injury, rather than hyperextension of the neck.
47) A 67-year-old man has had an indolent, unhealing ulcer at the heel of the right foot for several weeks. The patient began wearing a new pair of shoes shortly before the ulcer started and noticed a blister as the first anomaly at the site where the ulcer eventually developed. He indicates that neither the blister nor the ulcer ever gave him any pain. The ulcer is 3.5 cm in diameter, the ulcer base looks dirty, and there is hardly any granulation tissue. The skin around the ulcer looks normal. The patient has no sensation to pin prick anywhere in that foot. Peripheral pulses are weak but palpable. He is obese and has varicose veins, high cholesterol, and poorly controlled type 2 diabetes mellitus. Which of the following most accurately characterizes the ulcer?
A. Diabetic ulcer due to trauma, neuropathy, and microvascular disease
B. Ischemic ulcer due to arteriosclerosis
C. Ischemic ulcer due to embolization
D. Neoplastic in nature, probably squamous cell carcinoma
E. Stasis ulcer due to venous insufficiency
Explanation:
The correct answer is
A. Diabetic ulcers typically develop at pressure points, and the heel is a favorite location. The patient has evidence of neuropathy, and the correlation with the trauma inflicted by the new shoes is classic. Ischemic ulcers, whether due to arteriosclerosis (choice B) or embolization (choice C) are typically seen at the tip of the toes, as far away from the heart as one can get. Neoplasms (choice D) can indeed develop in long-standing ulcers, but the history would have been one of 10 or 20 years of healing and breaking down, before heaped up edges of cancer begin to develop. Stasis ulcers (choice E) are seen above the malleolus, surrounded by edematous, hyperpigmented skin.
48) A 25-year-old man is stabbed once in the right chest. The entrance wound is on the midaxillary line, at the level of the fifth intercostal space. He arrives at the emergency department moderately short of breath, but he is fully awake and alert, is talking with a normal tone of voice, and has no distended veins visible in his neck or forehead. His blood pressure is 130/75 mm Hg, and his pulse is 82/min. Physical examination of the chest shows the wound, which is not visibly “sucking air,” and demonstrates no breath sounds at all on the right side, which is tympanitic to percussion. There is no evidence of mediastinal displacement. Which of the following would be the most appropriate next step in management?
A. Cover the wound with a regular dressing and get a chest x-ray
B. Cover the wound with Vaseline gauze, taped on three sides
C. Endotracheal intubation
D. Insert a chest tube at the right pleural base
E. Insert an 18-gauge needle into the right pleural space at the second intercostal space
Explanation:
The correct answer is
A. The clinical picture is that of a pneumothorax, but there is no life-threatening situation that would prevent obtaining a radiologic diagnosis of the exact nature and extent of the problem. Then the appropriate therapy can be instituted. Covering the wound with Vaseline gauze (choice B) is the standard advice for sucking chest wounds to prevent further inflow of air into the pleural space. This is not happening here. Endotracheal intubation (choice C) is not needed if he has a good airway. A person who is fully awake and has a normal tone of voice has a normal airway. A chest tube (choice D) should not be inserted blindly, not knowing yet what is going on. He may very well need a tube at the base if the x-ray shows a hemothorax, but we might prefer to put it at the top if all he has is air. Insertion of a needle (choice E) is the correct answer when there is a life-threatening tension pneumothorax. In that case, he would have been in shock, with distended veins and mediastinal displacement.
49) The unrestrained front-seat passenger in a car that crashes sustains closed comminuted fractures of both femoral shafts. Shortly after admission, he develops a blood pressure of 80/50 mm Hg, a pulse rate of 110/min, and a venous pressure of zero. He becomes pale, cold, and clammy, but the rest of his physical examination and x-ray films of the chest and pelvis are unremarkable. A sonogram of the abdomen done in the emergency department is likewise negative. Which of the following is the most likely reason for the low blood pressure?
A. Blood loss at the fracture sites
B. Fat embolism
C. Neurogenic shock from pain
D. Unrecognized intracranial bleeding
E. Unrecognized pericardial tamponade
Explanation:
The correct answer is
A. Comminuted fractures of the femurs are known to be one of the few places in the body where enough occult blood loss may occur to lead to hypovolemic shock. Fat embolism (choice B) is also associated with long bone fractures, but the manifestations are those of respiratory failure, rather than hypovolemic shock. Neurogenic shock (choice C) would rarely occur from pain alone, being more common as a sequela of high spinal cord transection. When it happens, the patient is hypotensive but looks warm and flushed rather than cold and pale. Intracranial bleeding (choice D) can lead to neurologic symptoms, but not to hypovolemic shock. There is not enough room within the head to accumulate the sizable blood loss required to go into shock. Pericardial tamponade (choice E) would produce high central venous pressure.
50) A 25-year-old man is stabbed in the right chest. He comes in fully awake and alert, and, in a normal tone of voice, he states that he feels short of breath. His vital signs are normal and stable. On physical examination, he has no breath sounds at the right base, and only faint breath sounds at the apex. He is dull to percussion over the right base. A chest x-ray film confirms that he has a hemothorax on that side. Which of the following is the most appropriate next step in management?
A. Oxygen by mask, analgesics, and no specific intervention
B. Intubation and use of a respirator
C. Insertion of a chest tube in the right second intercostal space
D. Insertion of a chest tube at the right base
E. Exploratory thoracotomy
Explanation:
The correct answer is
D. Although he is hemodynamically stable, and thus presumably not “bleeding to death,” contaminated blood should not be left in the pleural space, where it could lead to the development of an empyema. A chest tube placed at the base should evacuate it. In doing so, we will also learn whether the amount of blood recovered justifies a more aggressive step to stop the bleeding. No specific intervention (choice A) is incorrect because that contaminated blood needs to come out. Intubation and respirator (choice B) are not needed. A patient who is awake and alert and speaking in a normal tone of voice has a good airway. He does not need intubation. Neither does he need a machine to breathe for him, when he is doing it spontaneously. A chest tube high in the pleural space (choice C) is the correct prescription for a pneumothorax, but not for a hemothorax. Air goes to the top, and blood goes to the bottom. To retrieve the blood, the tube has to be at the bottom. Thoracotomy (choice E) is seldom needed for a hemothorax. Bleeding is usually from the lung, and it stops by itself. When a systemic vessel is injured (typically an intercostal), we find a lot of blood when the tube is placed (more than 1000 or 1500 mL), or a substantial amount drains out in the ensuing few hours (more than 600 mL in 6 hours). Only in those cases is a thoracotomy indicated.
Tags: Surgery
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