surgical infections Flashcards
1
Q
what are concentrated in the region of bacterial invasion
A
complement, fibrinogen, and opsonins
2
Q
what are concentrated in the region of bacterial invasion
A
complement, fibrinogen, and opsonins
3
Q
mc type of SSI
A
superficial and incisional- range from simple cellulitis of the wound to overt infection of the wound bed above the fascia
4
Q
tx superficial and incisional SSI
A
oral abx (most are gram pos) for cellulitis and reopening of the wound for those w infx w incisional purulent drainage and involvement of deeper tissues
5
Q
deep incisional SSI
A
extend into muscle and fascia; require opening and freq surgical debridement of necrotic tissue
6
Q
wounds at what location are at high risk for fascial necrosis and dehiscence
A
abdomen
7
Q
tx deep incisional SSI
A
abx and cont daily local wound care
8
Q
more severe forms of deep incisional SSI
A
necrotizing fasciitis, systemic infx, sepsis
9
Q
ex of infx of organ/intracavitary space
A
peritonitis, intra abdominal abscess and empyema
10
Q
surgical skin prep
A
povidone-iodine solution or chlorhexidine containing solutions
11
Q
what are 2 key preventive measures
A
adequate tissue perforation and oxygenation
12
Q
minimum inhibitory concentration
A
refers to the lowest concentration necessary to visibly inhibit growth under typical conditions
13
Q
to insure adequate serum and tissue levels, initial abx are given how long prior to incision
A
1hr
14
Q
abx for cardiac or vascular
A
cefazolin (ancef), cefuroxime, or vanco
15
Q
abx for hip/knee arthroplasty
A
cefazolin (ancef), cefuroxime, or vanco
16
Q
abx colon
A
Cefotetan, cefoxitin, ampicillin/sulbactam or ertapenem
OR
Cefazolin or cefuroxime + metronidazole
If β-lactam allergy:
Clindamycin + aminoglycoside or quinolone or aztreonam
OR
Metronidazole with aminoglycoside or
Metronidazole + quinolone
17
Q
abx hysterectomy
A
cefotetan, cefazolin, cefoxitin, cefuroxime or Ampicillin/sulbactam
If β-lactam allergy
Clindamycin + aminoglycoside or quinolone or aztreonam
OR
Metronidazole + aminoglycoside or
Metronidazole + quinolone
OR
Clindamycin monotherapy
18
Q
how long is periop abx therapy cont for
A
19
Q
6 key quality indicators related to the periop manag of surgical pts that related to surgical infx according to SCIP and CMS
A
- Prophylactic antibiotic delivery within 60 minutes prior to incision
- Prophylactic antibiotics consistent with approved guidelines
- Cessation of prophylaxis within 24 hours following surgery
- Appropriate hair removal (clipping)
- Glucose control for cardiac surgery
- Normothermia for colorectal surgery
20
Q
all infx that occur after surgical procedures are considered
A
nosocomial (hospital acquired)
21
Q
fever that occurs in postop setting can be an early indication of
A
dev infx
22
Q
W’s of postop fever
A
wind (1-2d), water (2-3d), wound (3-5d), walking (5-7d), W abscess (7-10d), wonder drugs (anytime)
23
Q
usually early and first cause of temp elev postop
A
lung atelectasis
24
Q
4 major components to prevent HAP/VAP
A
(1) elevation of the head of the bed to 30°, (2) daily sedation vacation and assessment for weaning, (3) stress ulcer prophylaxis, and (4) venous thromboembolism prevention
25
a quantitative bronchial aspirate of what of aspirate is dx of invasive infx for VAP
>10^5 organisms/mL
26
abx use for pts in the hospital 10days
10d or immunocomp are at greater risk and abx should cover MRSA and resistant gram negative rods
27
tx for VAP
frequent airway suction;specific abx tx for 8 days
28
greatest risk factor for dev a UTI
presence of an indwelling bladder catheter
29
dx UTI
bacterial cx >100,000
30
when a postop pt w signs of infx dev a pleural effusion, the composition of fluid should be determined by
thoracentesis
31
transudative effusion
due ot inc hydrostatic forces and has low protein content
32
exudative effusion
inc permeability and has high protein content
33
what helps to differentiate exudates
LDH, glucose, pH, cell count, and gram stain
34
results of exudative effusions due to inflammation
pH 3xserum level
35
tx symptomatic pts or lg volume effusions assoc w characteristics assoc w exudate on thoracentesis
adequate drainage of the pleural space must be accomplished; abx
36
dx of exudate on imaging
ct scan w loculated rim enhancing pleural collection
37
mc cause of intra abd infx in surgical pt
perf or leakage from a hollow viscus that leads to bacterial seeding of the peritoneal cavity
38
2 response to perf or leakage of abd cavity
abscess formation or generalized peritonitis
39
primary peritonitis
spontan bacterial peritonitis that occurs wout breach of GI tract or peritoneal cavity, usually mono microbial, and seen in chronic alcoholics
40
secondary peritonitis
polymicrobial and occurs as result of spillage of gut organisms from GI tract or contamination of indwelling catheters
41
tertiary peritonitis
critically ill pts and persists or recurs at least 48hrs after apparent adequate manage, polymicrobial, and reflects a failure of host defense rather than source control
42
tx for any postop patient that demonstrates signs of systemic sepsis
broad spectrum abx
43
dx postop sepsis
blood cx, CT w PO and IV contrast*
44
blanching erythema of cellulitis caused by
group a strep and responds to penicillin tx
45
cellulitis
break in skin barrier, strep, warm to touch, diffuse erythema, tenderness, tx systemic abx and local wound care
46
furuncle, carbuncle
bacterial growth within skin glands/crypts, staph, localized induration, erythema, tenderness, swelling w purulent discharge,tx i/d, abx
47
hldradenitis suppurativa
bacterial growth within apocrine sweat glands, staph, multiple localized subcut abscesses, drainage, commonly axilla and groin, tx i/d small lesions, abx, lg needs wide local excision and skin grafting
48
lymphangitis
infx within lymphatics, strep, diffuse swelling, erythema of distal extremity w areas of inflamed streaks along lymphatic channels, tx local wound care, abx, removal fb, elevation extremity
49
gangrene, nsti's
destruction of healthy tissue by virulent microbial enzymes, strep/staph/clostridium,Necrotic skin/fascia, swelling and Induration, foul smelling discharge, crepitus with subcutaneous emphysema, frequently with toxic systemic signs and symptoms of sepsis
Radical débridement/amputation of involved tissues, aggressive local wound care with frequent débridement as necessary, parenteral broad-spectrum antibiotics
50
4 types of necrotizing soft tissue infx (NSTI)
cellulitis, fasciitis, myositis, vasculitis
51
what does non blanching erythema indicate
subdermal thrombosis of the nutrient blood supply of the skin; tx surgical debridement, high dose penicillin and clinda
52
clostridial myonecrosis or clostridial cellulitis
fulminant life threatening infx characterized by tissue necrosis and rapidly adv crepitus (gas gangrene); debridement and high dose penicillin
53
restlessness, headache, masseter muscle stiffness, and muscular contractions in area of the wound
tetanus (lockjaw); clostridium tetoni
54
tx tetanus
debridement and cleansing of all wounds in which devitalized, contaminated tissue is present
55
tetanus prone
>6hr, crush, avulsion, extensive abrasion, burns, frostbite, contaminants (soil, saliva) present
56
nontetanus prone
57
tetanus prophylaxis
unknown or
58
cause of breast abscess
staph
59
who is at higher risk for breast abscess
postpartum women
60
tx breast abscess
i/d, abx, bx
61
infx within crypts of anorectal canal and present as tender mass in perianal area
perirectal abscess
62
if perirectal abscess involves an invasive infx and results in sub cut tissue necrosis what is tx
wide debridement for salvage; colostomy diversion to avoid further soilage to area and sequelae of fecal incontinence if sphincter is involved
63
paronychia
staph infx of proximal fingernail that erupts at sulcus of the nail border
64
tx paronychia
i/d, resection of portion of embedded nail, hot soaks
65
felons
deep infx of terminal phalanx pulp space; occur after distal phalanx penetrating injuries and are tx by drainage; removal of nail may be necessary
66
neglected infections of the fingers may result in
tenosynovitis; infx extends along tendon sheath
67
organisms of bites human and animals
eikenella corrodens for humans and pasteurella for dogs/cats
68
abx for biliary tract infx
cefazolin or cefoxitin
69
mc inflammatory and infectious process in biliary tract
acute cholecystitis
70
acute peritonitis
bacteria present within the normally sterile peritoneal cavity
71
ct finding of peritonitis
upright chest roentgenogram commonly shows pneumoperitoneum beneath a hemidiaphragm with acute GI perforation and small amounts of pneumoperitoneum
72
all pts w ulcer assoc perf should be assessed for presence of
helicobacter pylori
73
abx for appendix
aerobic (e coli) and anaerobic (bacteroides fragilis) coverage
74
cause and tx fungal infx
Candida; fluconazole, ketoconazole, miconazole, nystatin
75
3 mc viral illnesses of concern for injury (needle stick)
hep B*, hep C, HIV
76
A 32-year-old man is seen in the emergency department 45 minutes after a motor vehicle collision. His only injury is a long linear laceration beginning on the left temporal forehead at the hairline and extending posteriorly for 10 cm. The edges are still bleeding briskly and the EMTs described a large amount of blood at the scene. He did not lose consciousness. His last tetanus booster was 4 years ago. Which of the following is required for tetanus prophylaxis In this patient?
A. Tetanus immune globulin only
B. Nothing further at this time
C. Tetanus toxoid only
D. Tetanus immune globulin followed by a single tetanus toxoid booster
E. Tetanus immune globulin followed by three tetanus boosters
Answer: B
Wounds prone to the development of tetanus Include those with extensive contamination with soil, deep puncture wounds from metal objects, exposure Injury complicated with frostbite, and wounds >6 hours from time of Injury (Table 8-8.). Linear lacerations In general are not prone to tetanus. The extent of blood loss does not affect the need for tetanus booster administration. The patient last received tetanus toxoid
77
A 48-year-old man Is being evaluated In the emergency department with fevers, chills, and abdominal pain for the past 24 hours. He has a history of hepatitis C infection following a blood transfusion 14 years ago for a large scalp laceration and orthopedic injuries sustained In a motor vehicle collision. He has not been to a physician for 5 years. He does not smoke or drink alcohol. He takes no medications. His temperature is 39°C and vital signs are: blood pressure (BP) 90/50 mm Hg, pulse 110/minute, and respirations 26/minute. A CT scan shows a single stone in the gallbladder that does not appear to be obstructing. The bile ducts are normal caliber and the gallbladder wall Is not thickened. There Is a moderate amount of fluid, mild small bowel distention, and stranding around the sigmoid colon as well as a small amount of free Intraperitoneal gas around the liver. An aspirate of the peritoneal fluid shows leukocytes and mixed Gram positives and negatives on Gram stain. Laboratory values show a WBC of 19,000/mm3, total bilirubin 1.2 mg/dL, and alkaline phosphatase 40 U/L. In addition to fluid resuscitation and broad-spectrum antibiotics, what is the best step in management?
A. Laparoscopic cholecystectomy
B. Long-term antibiotics only
C. Laparotomy
D. Magnetic resonance cholangiopancreatography (MRCP)
E. Endoscopic retrograde cholangiopancreatography (ERCP)
Answer: C
This patient has secondary peritonitis. This usually involves perforation of a hollow vlscus and thus involves contamination of the peritoneal cavity with multiple organisms. Gram stain and culture of the peritoneal fluid usually shows a single organism In patients with primary peritonitis and this can be treated with antibiotics without surgical Intervention. In this scenario, the CT scan shows stranding around the sigmoid and fluid and evidence of free air suggestive of a diverticulitis with fecal peritonitis. Patients with underlying liver disease are prone to gallstones and are a common finding. There Is no evidence of common bile duct obstruction that warrants further investigation since the alkaline phosphatase is normal.
78
A 42-year-old woman Is seen In the infectious disease clinic because of a small laceration. She is a surgeon and was assisting a surgical resident with a colon resection when she was accidentally cut with a scalpel blade during the procedure. She has received all required Immunizations. Antibodies against which virus could be measured in order to assess the effectiveness of the only vaccine to prevent Infection potentially transmitted from the patient to the surgeon during the operative procedure?
A. Human immunodeficiency virus
B. Hepatitis C
C. Hepatitis B
D. Cytomegalovirus
E. Tuberculosis
Answer: C
HIV, hepatitis B, hepatitis C, and cytomegalovirus are transmitted by body fluids and blood; therefore, they pose an occupational risk to the surgeon. There Is currently a highly effective vaccine for the prevention of hepatitis B in the host. No such vaccine is available for the other viral Infections. Tuberculosis is not a virus but also poses a risk to health care workers.
79
A 30-year-old man is in the hospital recovering from splenectomy for a ruptured spleen sustained in a motor vehicle collision. He has otherwise been healthy and was not taking medications prior to the injury. A temperature of 102°F Is noted on the second postoperative day. Vital signs are BP 130/80 mm Hg, pulse 100/minute, and respirations 18/minute. His pain is moderately controlled with morphine using patient-controlled analgesia (PCA). Breath sounds are diminished at both bases, more so on the left. His abdomen is mildly distended, soft and tender near the Incision. The incision appears to be healing without a problem. What Is the most likely cause for his fever?
A. Atelectasis and pulmonary infection
B. Peritonitis
C. Urinary tract Infection
D. Suppurative thrombophlebitis
E. Cardiac contusion
Answer: A
Early postoperative fever Is usually the result of atelectasis and subsequent pulmonary infection (Table 8-6). In this scenario, because of the close proximity of the left hemidiaphragm to the spleen, an Infiltrate In the left lower lobe of the lung Is a high probability. An adequately drained urinary tract In a young person seldom gives a high fever this early in the postoperative period. Although peritonitis from injury to a surrounding structure during the splenectomy (i.e., pancreas, stomach, or bowel) Is a possibility, It is much less likely than a pulmonary source. Cardiac contusion does not elicit a febrile response.
80
A 25-year-old man is seen in the emergency department because of a painful swollen forearm. Two days ago, he sustained a small laceration to his left forearm while clearing brush. It caused only minor discomfort until about 12 hours ago when the area around the laceration became more red and swollen. He has otherwise been healthy. He takes no medications. His temperature Is 38°C. There is a 2-cm superficial laceration on the dorsum of his left forearm with 15-cm diameter surrounding erythema that is quite tender. The edges of the erythema were marked and 20 minutes later the erythema has extended another cm beyond the mark. The most likely causative organism is
A. methicillin-resistant Staphylococcus aureus.
B. β-Hemolytic Streptococcus A.
C. Escherichia coli.
D. Streptococcus faecalis.
E. Candida albicans.
Answer: B
Although cellulitis may be caused by any organism, the most likely early organism would be β-hemolytic Streptococcus A. methicillin-resistant Staphylococcus aureus more commonly causes local Inflammation and pus formation. The other three species are rarely isolated from skin infections but more commonly are seen In infections involving the gastrointestinal tract.
81
mc type of SSI
superficial and incisional- range from simple cellulitis of the wound to overt infection of the wound bed above the fascia
82
tx superficial and incisional SSI
oral abx (most are gram pos) for cellulitis and reopening of the wound for those w infx w incisional purulent drainage and involvement of deeper tissues
83
deep incisional SSI
extend into muscle and fascia; require opening and freq surgical debridement of necrotic tissue
84
wounds at what location are at high risk for fascial necrosis and dehiscence
abdomen
85
tx deep incisional SSI
abx and cont daily local wound care
86
more severe forms of deep incisional SSI
necrotizing fasciitis, systemic infx, sepsis
87
ex of infx of organ/intracavitary space
peritonitis, intra abdominal abscess and empyema
88
surgical skin prep
povidone-iodine solution or chlorhexidine containing solutions
89
what are 2 key preventive measures
adequate tissue perforation and oxygenation
90
minimum inhibitory concentration
refers to the lowest concentration necessary to visibly inhibit growth under typical conditions
91
to insure adequate serum and tissue levels, initial abx are given how long prior to incision
1hr
92
abx for cardiac or vascular
cefazolin (ancef), cefuroxime, or vanco
93
abx for hip/knee arthroplasty
cefazolin (ancef), cefuroxime, or vanco
94
abx colon
Cefotetan, cefoxitin, ampicillin/sulbactam or ertapenem
OR
Cefazolin or cefuroxime + metronidazole
If β-lactam allergy:
Clindamycin + aminoglycoside or quinolone or aztreonam
OR
Metronidazole with aminoglycoside or
Metronidazole + quinolone
95
abx hysterectomy
cefotetan, cefazolin, cefoxitin, cefuroxime or Ampicillin/sulbactam
If β-lactam allergy
Clindamycin + aminoglycoside or quinolone or aztreonam
OR
Metronidazole + aminoglycoside or
Metronidazole + quinolone
OR
Clindamycin monotherapy
96
how long is periop abx therapy cont for
97
6 key quality indicators related to the periop manag of surgical pts that related to surgical infx according to SCIP and CMS
1. Prophylactic antibiotic delivery within 60 minutes prior to incision
2. Prophylactic antibiotics consistent with approved guidelines
3. Cessation of prophylaxis within 24 hours following surgery
4. Appropriate hair removal (clipping)
5. Glucose control for cardiac surgery
6. Normothermia for colorectal surgery
98
all infx that occur after surgical procedures are considered
nosocomial (hospital acquired)
99
fever that occurs in postop setting can be an early indication of
dev infx
100
W's of postop fever
wind (1-2d), water (2-3d), wound (3-5d), walking (5-7d), W abscess (7-10d), wonder drugs (anytime)
101
usually early and first cause of temp elev postop
lung atelectasis
102
4 major components to prevent HAP/VAP
(1) elevation of the head of the bed to 30°, (2) daily sedation vacation and assessment for weaning, (3) stress ulcer prophylaxis, and (4) venous thromboembolism prevention
103
a quantitative bronchial aspirate of what of aspirate is dx of invasive infx for VAP
>10^5 organisms/mL
104
abx use for pts in the hospital 10days
10d or immunocomp are at greater risk and abx should cover MRSA and resistant gram negative rods
105
tx for VAP
frequent airway suction;specific abx tx for 8 days
106
greatest risk factor for dev a UTI
presence of an indwelling bladder catheter
107
dx UTI
bacterial cx >100,000
108
when a postop pt w signs of infx dev a pleural effusion, the composition of fluid should be determined by
thoracentesis
109
transudative effusion
due ot inc hydrostatic forces and has low protein content
110
exudative effusion
inc permeability and has high protein content
111
what helps to differentiate exudates
LDH, glucose, pH, cell count, and gram stain
112
results of exudative effusions due to inflammation
pH 3xserum level
113
tx symptomatic pts or lg volume effusions assoc w characteristics assoc w exudate on thoracentesis
adequate drainage of the pleural space must be accomplished; abx
114
dx of exudate on imaging
ct scan w loculated rim enhancing pleural collection
115
mc cause of intra abd infx in surgical pt
perf or leakage from a hollow viscus that leads to bacterial seeding of the peritoneal cavity
116
2 response to perf or leakage of abd cavity
abscess formation or generalized peritonitis
117
primary peritonitis
spontan bacterial peritonitis that occurs wout breach of GI tract or peritoneal cavity, usually mono microbial, and seen in chronic alcoholics
118
secondary peritonitis
polymicrobial and occurs as result of spillage of gut organisms from GI tract or contamination of indwelling catheters
119
tertiary peritonitis
critically ill pts and persists or recurs at least 48hrs after apparent adequate manage, polymicrobial, and reflects a failure of host defense rather than source control
120
tx for any postop patient that demonstrates signs of systemic sepsis
broad spectrum abx
121
dx postop sepsis
blood cx, CT w PO and IV contrast*
122
blanching erythema of cellulitis caused by
group a strep and responds to penicillin tx
123
cellulitis
break in skin barrier, strep, warm to touch, diffuse erythema, tenderness, tx systemic abx and local wound care
124
furuncle, carbuncle
bacterial growth within skin glands/crypts, staph, localized induration, erythema, tenderness, swelling w purulent discharge,tx i/d, abx
125
hldradenitis suppurativa
bacterial growth within apocrine sweat glands, staph, multiple localized subcut abscesses, drainage, commonly axilla and groin, tx i/d small lesions, abx, lg needs wide local excision and skin grafting
126
lymphangitis
infx within lymphatics, strep, diffuse swelling, erythema of distal extremity w areas of inflamed streaks along lymphatic channels, tx local wound care, abx, removal fb, elevation extremity
127
gangrene, nsti's
destruction of healthy tissue by virulent microbial enzymes, strep/staph/clostridium,Necrotic skin/fascia, swelling and Induration, foul smelling discharge, crepitus with subcutaneous emphysema, frequently with toxic systemic signs and symptoms of sepsis
Radical débridement/amputation of involved tissues, aggressive local wound care with frequent débridement as necessary, parenteral broad-spectrum antibiotics
128
4 types of necrotizing soft tissue infx (NSTI)
cellulitis, fasciitis, myositis, vasculitis
129
what does non blanching erythema indicate
subdermal thrombosis of the nutrient blood supply of the skin; tx surgical debridement, high dose penicillin and clinda
130
clostridial myonecrosis or clostridial cellulitis
fulminant life threatening infx characterized by tissue necrosis and rapidly adv crepitus (gas gangrene); debridement and high dose penicillin
131
restlessness, headache, masseter muscle stiffness, and muscular contractions in area of the wound
tetanus (lockjaw); clostridium tetoni
132
tx tetanus
debridement and cleansing of all wounds in which devitalized, contaminated tissue is present
133
tetanus prone
>6hr, crush, avulsion, extensive abrasion, burns, frostbite, contaminants (soil, saliva) present
134
nontetanus prone
135
tetanus prophylaxis
unknown or
136
cause of breast abscess
staph
137
who is at higher risk for breast abscess
postpartum women
138
tx breast abscess
i/d, abx, bx
139
infx within crypts of anorectal canal and present as tender mass in perianal area
perirectal abscess
140
if perirectal abscess involves an invasive infx and results in sub cut tissue necrosis what is tx
wide debridement for salvage; colostomy diversion to avoid further soilage to area and sequelae of fecal incontinence if sphincter is involved
141
paronychia
staph infx of proximal fingernail that erupts at sulcus of the nail border
142
tx paronychia
i/d, resection of portion of embedded nail, hot soaks
143
felons
deep infx of terminal phalanx pulp space; occur after distal phalanx penetrating injuries and are tx by drainage; removal of nail may be necessary
144
neglected infections of the fingers may result in
tenosynovitis; infx extends along tendon sheath
145
organisms of bites human and animals
eikenella corrodens for humans and pasteurella for dogs/cats
146
abx for biliary tract infx
cefazolin or cefoxitin
147
mc inflammatory and infectious process in biliary tract
acute cholecystitis
148
acute peritonitis
bacteria present within the normally sterile peritoneal cavity
149
ct finding of peritonitis
upright chest roentgenogram commonly shows pneumoperitoneum beneath a hemidiaphragm with acute GI perforation and small amounts of pneumoperitoneum
150
all pts w ulcer assoc perf should be assessed for presence of
helicobacter pylori
151
abx for appendix
aerobic (e coli) and anaerobic (bacteroides fragilis) coverage
152
cause and tx fungal infx
Candida; fluconazole, ketoconazole, miconazole, nystatin
153
3 mc viral illnesses of concern for injury (needle stick)
hep B*, hep C, HIV
154
A 32-year-old man is seen in the emergency department 45 minutes after a motor vehicle collision. His only injury is a long linear laceration beginning on the left temporal forehead at the hairline and extending posteriorly for 10 cm. The edges are still bleeding briskly and the EMTs described a large amount of blood at the scene. He did not lose consciousness. His last tetanus booster was 4 years ago. Which of the following is required for tetanus prophylaxis In this patient?
A. Tetanus immune globulin only
B. Nothing further at this time
C. Tetanus toxoid only
D. Tetanus immune globulin followed by a single tetanus toxoid booster
E. Tetanus immune globulin followed by three tetanus boosters
Answer: B
Wounds prone to the development of tetanus Include those with extensive contamination with soil, deep puncture wounds from metal objects, exposure Injury complicated with frostbite, and wounds >6 hours from time of Injury (Table 8-8.). Linear lacerations In general are not prone to tetanus. The extent of blood loss does not affect the need for tetanus booster administration. The patient last received tetanus toxoid
155
A 48-year-old man Is being evaluated In the emergency department with fevers, chills, and abdominal pain for the past 24 hours. He has a history of hepatitis C infection following a blood transfusion 14 years ago for a large scalp laceration and orthopedic injuries sustained In a motor vehicle collision. He has not been to a physician for 5 years. He does not smoke or drink alcohol. He takes no medications. His temperature is 39°C and vital signs are: blood pressure (BP) 90/50 mm Hg, pulse 110/minute, and respirations 26/minute. A CT scan shows a single stone in the gallbladder that does not appear to be obstructing. The bile ducts are normal caliber and the gallbladder wall Is not thickened. There Is a moderate amount of fluid, mild small bowel distention, and stranding around the sigmoid colon as well as a small amount of free Intraperitoneal gas around the liver. An aspirate of the peritoneal fluid shows leukocytes and mixed Gram positives and negatives on Gram stain. Laboratory values show a WBC of 19,000/mm3, total bilirubin 1.2 mg/dL, and alkaline phosphatase 40 U/L. In addition to fluid resuscitation and broad-spectrum antibiotics, what is the best step in management?
A. Laparoscopic cholecystectomy
B. Long-term antibiotics only
C. Laparotomy
D. Magnetic resonance cholangiopancreatography (MRCP)
E. Endoscopic retrograde cholangiopancreatography (ERCP)
Answer: C
This patient has secondary peritonitis. This usually involves perforation of a hollow vlscus and thus involves contamination of the peritoneal cavity with multiple organisms. Gram stain and culture of the peritoneal fluid usually shows a single organism In patients with primary peritonitis and this can be treated with antibiotics without surgical Intervention. In this scenario, the CT scan shows stranding around the sigmoid and fluid and evidence of free air suggestive of a diverticulitis with fecal peritonitis. Patients with underlying liver disease are prone to gallstones and are a common finding. There Is no evidence of common bile duct obstruction that warrants further investigation since the alkaline phosphatase is normal.
156
A 42-year-old woman Is seen In the infectious disease clinic because of a small laceration. She is a surgeon and was assisting a surgical resident with a colon resection when she was accidentally cut with a scalpel blade during the procedure. She has received all required Immunizations. Antibodies against which virus could be measured in order to assess the effectiveness of the only vaccine to prevent Infection potentially transmitted from the patient to the surgeon during the operative procedure?
A. Human immunodeficiency virus
B. Hepatitis C
C. Hepatitis B
D. Cytomegalovirus
E. Tuberculosis
Answer: C
HIV, hepatitis B, hepatitis C, and cytomegalovirus are transmitted by body fluids and blood; therefore, they pose an occupational risk to the surgeon. There Is currently a highly effective vaccine for the prevention of hepatitis B in the host. No such vaccine is available for the other viral Infections. Tuberculosis is not a virus but also poses a risk to health care workers.
157
A 30-year-old man is in the hospital recovering from splenectomy for a ruptured spleen sustained in a motor vehicle collision. He has otherwise been healthy and was not taking medications prior to the injury. A temperature of 102°F Is noted on the second postoperative day. Vital signs are BP 130/80 mm Hg, pulse 100/minute, and respirations 18/minute. His pain is moderately controlled with morphine using patient-controlled analgesia (PCA). Breath sounds are diminished at both bases, more so on the left. His abdomen is mildly distended, soft and tender near the Incision. The incision appears to be healing without a problem. What Is the most likely cause for his fever?
A. Atelectasis and pulmonary infection
B. Peritonitis
C. Urinary tract Infection
D. Suppurative thrombophlebitis
E. Cardiac contusion
Answer: A
Early postoperative fever Is usually the result of atelectasis and subsequent pulmonary infection (Table 8-6). In this scenario, because of the close proximity of the left hemidiaphragm to the spleen, an Infiltrate In the left lower lobe of the lung Is a high probability. An adequately drained urinary tract In a young person seldom gives a high fever this early in the postoperative period. Although peritonitis from injury to a surrounding structure during the splenectomy (i.e., pancreas, stomach, or bowel) Is a possibility, It is much less likely than a pulmonary source. Cardiac contusion does not elicit a febrile response.
158
A 25-year-old man is seen in the emergency department because of a painful swollen forearm. Two days ago, he sustained a small laceration to his left forearm while clearing brush. It caused only minor discomfort until about 12 hours ago when the area around the laceration became more red and swollen. He has otherwise been healthy. He takes no medications. His temperature Is 38°C. There is a 2-cm superficial laceration on the dorsum of his left forearm with 15-cm diameter surrounding erythema that is quite tender. The edges of the erythema were marked and 20 minutes later the erythema has extended another cm beyond the mark. The most likely causative organism is
A. methicillin-resistant Staphylococcus aureus.
B. β-Hemolytic Streptococcus A.
C. Escherichia coli.
D. Streptococcus faecalis.
E. Candida albicans.
Answer: B
Although cellulitis may be caused by any organism, the most likely early organism would be β-hemolytic Streptococcus A. methicillin-resistant Staphylococcus aureus more commonly causes local Inflammation and pus formation. The other three species are rarely isolated from skin infections but more commonly are seen In infections involving the gastrointestinal tract.
