Surgery 1 Flashcards

1
Q

Human bite wounds are prone to polymicrobial infection with aerobic and anaerobic oral flora. What are the 5 most common organisms?

A
Streptococci
S. aureus
Eikenella corrodens
H. influenzae
Beta-lactamase-producing anaerobic bacteria
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What is the best empiric treatment for human bite wounds and why?

A

Amoxicillin-clavulanate (Augmentin)

Excellent coverage of GP, GN, and beta-lactamase-producing oral anaerobes (clavulanate inhibits beta-lactamase)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

In addition to empiric antibiotics, what should be done to manage a patient with a human bite wound?

A

Surgical debridement is usually necessary.
Wounds are typically left open to drain and heal by secondary intention (high risk of infection with closure)
Tetanus vaccination if not up to date

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

General coverage/use of ampicillin?

A

Effective against many GP and GN

Used for URIs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

General coverage/use of ciprofloxacin?

A

Many GN organisms, some GP (excluding most streptococci)

GU and GI infections

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

General coverage/use of clindamycin?

A

GP, anaerobes

Some lung abscesses, SSTIs, female upper reproductive tract infections (in combination with other agents)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

General coverage/use of erythromycin?

A

Some atypicals

2nd line to treat gonococcal or chlamydial urethritis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Patients suffering rapid deceleration blunt chest trauma are at high risk for ___ injury.

A

Aortic

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

X-ray findings suggestive of aortic injury?

A

Widened mediastinum
Large left-sided hemothorax
Deviation of the mediastinum to the right
Disruption of the normal aortic contour

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

How should the diagnosis of aortic injury be confirmed?

A

CT scanning

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

List the major risk factors for developing infected foot ulcers in patients with diabetes.

A
  1. Peripheral neuropathy leading to impaired recognition of minor damage
  2. Hyperglycemia leading to impaired immunity
  3. Peripheral artery disease further contributing to impaired healing once a wound is present
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

In patients with a diabetic foot ulcer, what should be done next?

A

Assess for extent of infection

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What 3 factors increase the likelihood of osteomyelitis in a patient with a diabetic foot ulcer?

A
  1. Positive probe-to-bone test
  2. Large ulcer (>2 cm^2)
  3. Ulcer lasting 1+ weeks
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What is the most specific diagnostic test for osteomyelitis?

A

Bone biopsy and culture

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Management of a foot ulcer complicated by osteomyelitis?

A

Surgical debridement of necrotic material and prolonged (multiple weeks) antimicrobial therapy

Amputation is the option of last resort

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What is the first-line imaging study for women 30+ with a palpable breast mass?

A

Mammography

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What is required to confirm the diagnosis of a palpable mass?

A

Biopsy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What is a popliteal (Baker) cyst?

A

Extrusion of synovial fluid from the knee joint space into the semimembranous/gastrocnemius bursa through a communication between the joint and the bursa

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Risk factors for popliteal cyst?

A

Trauma

Underlying joint disease

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Clinical presentation of a popliteal cyst?

A

Asymptomatic bulge behind the knee that diminishes with flexion

Posterior knee pain, swelling, stiffness

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Complications of a popliteal cyst?

A
  1. Venous compression (leg/ankle swelling)
  2. Dissection into the calf (erythema, edema, positive Homan sign)
  3. Cyst rupture (acute calf pain, warmth, erythema, ecchymosis -> crescent sign at the medial malleolus)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What is used to confirm the diagnosis of a popliteal cyst?

A

U/S

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

___ presents with subacute medial knee pain. Examination shows a well-defined area of tenderness over the medial tibial plateau below the joint line.

A

Pes anserinus pain syndrome (anserine bursitis)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Common clinical features of compartment syndrome?

A

Pain out of proportion to the injury (does not respond well to narcotics)
Pain increased on passive stretch
Rapidly increasing and tense swelling
Paresthesia (early)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Uncommon clinical features of compartment syndrome?
``` Decreased sensation Motor weakness (within hours) Paralysis (late) Decreased distal pulses (uncommon) Pallor (uncommon) ```
26
Causes of compartment syndrome?
Direct trauma Prolonged compression of an extremity After revascularization of an acutely ischemic limb
27
Diagnose compartment syndrome?
Measuring compartment pressures in the affected extremity (unless high-risk, then clinical dx acceptable)
28
What is the most critical prognostic indicator for compartment syndrome?
Time to fasciotomy
29
Treatment of choice for compartment syndrome?
Fasciotomy
30
Why can diaphragmatic hernia occur with blunt abdominal trauma?
May cause a sudden increase in intraabdominal pressure that overcomes the muscular strength of the diaphragm and leads to large radial tears in the muscle; the resultant diaphragmatic rupture allows leakage of intraabdominal contents into the chest, causing compression of the lungs and mediastinal deviation
31
Why is diaphragmatic rupture more common the left side?
Right side tends to be protected by the liver
32
___ is typically caused by 3+ adjacent rib fractures that break in 2 places and create an unstable chest wall segment that moves in a paradoxic motion with respiration.
Flail chest
33
CXR findings in diaphragmatic rupture?
Deviation of mediastinal contents to the opposite side | Elevation of the hemidiaphragm on the CXR
34
What can be diagnostic of diaphragmatic rupture?
CXR showing an NG tube in the pulmonary cavity
35
True or false - multiple liver masses are more likely to be the result of primary liver malignancy than metastatic disease or infectious causes.
False - multiple liver masses are much more likely to be the result of metastatic disease than infectious causes or primary liver malignancy
36
Common diseases that metastasize to the liver? Most common?
Primary tumors of the GI tract, lung, and breast Most common - colorectal cancer (blood from the colon moves through the portal circulation directly to the liver)
37
In the setting of an abdominal CT showing multiple liver lesions, what is the most appropriate next diagnostic step?
Colonoscopy - localizes the tumor and provides a tissue diagnosis (Abdominal CT is a useful screening test but can often miss primary intraluminal tumors)
38
What is a pancreatic pseudocyst?
Mature walled-off pancreatic fluid collections (usually no necrosis or solid material) surrounded by a thick fibrous capsule and containing enzyme-rich fluid, tissue, and debris
39
Presentation of pancreatic pseudocyst?
Hx of alcohol use/recent pancreatitis Progressive abdominal distention, N/V CT with round, well-circumscribed encapsulated fluid collection in the pancreatic bed Elevated amylase
40
Complications of pancreatic pseudocyst?
``` Spontaneous infection Duodenal or biliary obstruction Pseudoaneurysm (digestion of adjacent vessels) Pancreatic ascites Pleural effusion ```
41
Management of a patient with a pseudocyst who has minimal or no symptoms and no complications?
Expectant management (symptomatic therapy, NPO)
42
When is endoscopic drainage indicated in patients with pancreatic pseudocyst?
Those with significant symptoms, infected pseudocyst, or evidence of pseudoaneurysm
43
Patients with Crohn disease or any other small intestinal disorder resulting in fat malabsorption are predisposed to ___ and thus to nephrolithiasis. Why?
Hyperoxaluria; oxalate is obatined from the diet and is a normal product of human metabolism Symptomatic hyperoxaluria is classically the result of increased absorption in the gut. Normally, calcium binds oxalate to prevent its absorption. In patients with fat malabsorption, calcium is preferentially bound by fat leaving oxalate unbound and free to be absorbed.
44
Presentation of acute mesenteric ischemia?
Rapid onset of periumbilical pain (often severe) Pain out of proportion to exam findings Hematochezia (late complication)
45
Risk factors for acute mesenteric ischemia?
Atherosclerosis (acute on chronic) Embolic source (thrombus, vegetations) Hypercoagulable disorders
46
Lab findings of acute mesenteric ischemia?
Leukocytosis Elevated amylase and phosphate levels Metabolic acidosis (elevated lactate)
47
Dx acute mesenteric ischemia?
CT (preferred) or MR angiography Mesenteric angiography if dx unclear
48
Progression of acute mesenteric ischemia to bowel infarction causes what complications?
Focal pain Peritoneal signs Rectal bleeding Sepsis
49
Risk factors for Entamoeba histolytica infection?
Travel/residence in developing nations Contaminated food/water Fecal-oral sexual transmission (rare)
50
Presentation of E. histolytica infection?
90% asymptomatic Colitis (diarrhea, bloody stool with mucus, abdominal pain) Liver abscess (RUQ pain, fever) -Complications: rupture to pleura/peritoneum
51
Dx E. histolytica infection?
Stool O&P Stool antigen testing (colitis) E. histolytica serology (liver abscess)
52
Rx E. histolytica infection?
Metronidazole + intraluminal antibiotic (eg, paromomycin)
53
Peripheral eosinophilia is associated with ___ infections.
Helminthic (not with protozoal)
54
Characteristic imaging finding of E. histolytica liver abscess?
Single subcapsular low-density lesion in the right lobe of the liver
55
Polymicrobial pyogenic (bacterial) abscesses share similar clinical and radiographic appearances with amebic abscesses. What are some unique/expected findings of a bacterial abscess?
Associated with jaundice | More common in patients with DM or underlying hepatobiliary or pancreatic disease
56
A pulsatile groin mass below the inguinal ligament is characteristic of a ___.
Femoral artery aneurysm
57
A femoral artery aneurysm often presents with anterior thigh pain caused by?
Compression of the femoral nerve that runs lateral to the artery
58
Femoral artery aneurysm is the second most common peripheral artery aneurysm after ___ aneurysm. They may be associated with a ___.
Popliteal; AAA
59
Compare the locations of femoral, inguinal, and indirect hernias.
Femoral: below the inguinal ligament Inguinal: above the inguinal ligament Indirect: may descend into the scrotum
60
Chronic epigastric pain that suddenly worsens and becomes diffuse with a pneumoperitoneum is concerning for ___.
Perforated PUD
61
Populations at risk for scurvy (vitamin C deficiency)?
Alcohol/drug abuse Severe malnourishment Poor fruit/vegetable intake
62
Signs of scurvy typically arise within ___ of deficiency.
3 months
63
Presentation of scurvy?
Cutaneous: petechia, follicular hemorrhage, bruising, coiled hairs Gingival: bleeding/receding gums, dental caries Constitutional: arthralgias, weakness, malaise, depression Impaired wound healing Vasomotor instability (if severe/prolonged) With progression: hemolytic anemia, edema
64
Dx scurvy?
Serum ascorbic acid level
65
Rx scurvy?
Oral/injectable vitamin C resolves most symptoms within days
66
What is the role of vitamin C?
Essential dietary nutrient that acts as a reversible reducing agent and plays a crucial role in fatty acid transport and collagen synthesis
67
What is the most commonly dislocated joint in the body and why?
Glenohumeral joint due to the shallow articulation between the humeral head and the glenoid fossa of the scapula
68
The shoulder may dislocate anteriorly, inferiorly, or posteriorly - which is most common?
Anterior
69
What type of injury typically causes anterior shoulder dislocations?
A blow to an externally rotated and abducted arm
70
Most common nerve injury secondary to anterior shoulder dislocation and the effects of this injury?
Axillary nerve Loss of innervation of teres minor and deltoid (weakened shoulder abduction) Loss of sensation of the skin over the lateral shoulder
71
The extensor muscles of the wrist and digits are primarily innervated by branches of the ___ nerve, which also provides sensory innervation to the posterior arm, forearm, and dorsolateral hand.
Radial
72
Common causes of radial nerve injury?
Humeral mid-shaft fractures | Improperly fitted crutches
73
The biceps reflex is mediated by C5 and C6 spinal nerves, with muscular innervation via the ___.
Musculocutaneous nerve (lateral cod of the brachial plexus)
74
Traumatic injuries to the musculocutaneous nerve are uncommon, but can occasionally be seen in ___.
High-velocity MVCs
75
The ___ nerve may be injured by fracture of the medial epicondyle of the humerus or, more distally, by deep lacerations of the anterior wrist. Symptoms include claw hand from paralysis of the intrinsic muscles of the hand as well as sensory loss involving the medial hand.
Ulnar
76
The ___ nerve innervates the serratus anterior muscle.
Long thoracic
77
Causes of scapular winging 2/2 injury of the long thoracic nerve?
Deep lacerations to the axillary region and axillary lymphadenectomy
78
Primary treatment for papillary thyroid cancer?
Surgical resection followed by adjuvant therapy with radioiodine ablation (IF increased risk of recurrence)
79
Patients at increased risk of recurrence of papillary thyroid cancer should receive adequate doses of thyroid replacement - why?
Suppress TSH, which can stimulate growth of occult residual or metastatic disease
80
___ is a marker for medullary thyroid cancer - why?
Calcitonin; it arises from parafollicular C cells of the thyroid gland
81
What are 2 possible early complications of operation on the abdominal aorta?
Bowel ischemia and infarction
82
What causes bowel ischemia following AAA repair?
Inadequate colonic collateral arterial perfusion to the left and sigmoid colon after loss of the inferior mesenteric artery during aortic graft placement
83
Cause of penile fracture?
Rupture of the corpus cavernosum due to a traumatic tear in the tunica albuginea (which envelopes the corpus cavernosum)
84
Presentation of penile fracture?
Audible snapping sensation, detumescence, minimal to severe pain (depending on severity); hematoma forms rapidly, causing bending of the shaft of the penis at the fracture site
85
Dx of penile fracture?
Clinical
86
Rx penile fracture?
Surgical management (urological emergency)
87
When is a retrograde urethrogram indicated in the setting of suspected penile fracture?
Suspected urethral injury (blood at the meatus, hematuria, dysuria, urinary retention)
88
Best diagnostic test for acute diverticulitis and why?
Abdominal CT scan (oral and IV contrast) - also allows for differentiation from other causes of pain Sensitivity 94% Sepcificity 99%
89
Rx acute diverticulitis?
Bowel rest | ABX (eg, ciprofloxacin, metronidazole)
90
What causes urinary urgency, frequency, or dysuria in acute diverticulitis in 10-15% of patients?
Bladder irritation from an inflamed sigmoid colon
91
Findings suggestive of diverticular disease on CT?
``` Increased inflammation in pericolic fat Presence of diverticula Bowel wall thickening Soft tissue masses (phlegmons) Pericolic fluid collections suggesting abscess ```
92
Barium contrast enema can detect strictures or inflammation in ___.
UC/Crohn disease
93
What procedures are contraindicated in the setting of acute diverticulitis?
Barium contrast enema (until perf has been ruled out) | Sigmoidoscopy or colonoscopy (may cause perf)