Surgical infection and antibiotics Flashcards
(91 cards)
1
Q
defined by the presence of microorganism in host tissue or the bloodstream
A
Infection
2
Q
Systemic manifestation that is noted with individual who has infection e.g rubor, calor, dolor, tachypnea
A
systemic inflammatory response(SIRS)
3
Q
documented or suspected infection with SIRS
A
sepsis
4
Q
sepsis combined with the presence of new onset organ failure, eg. Pts. w/ oliguria, hypotension
A
sever sepsis
5
Q
state of acute circulatory failure identified by the presence of persistent arterial hypotension despite adequate fluid resuscitation
A
septic shock
6
Q
occurs 40% in patients with sever sepsis
A
septic shock
7
Q
other conditions that causes SIRS
A
trauma,aspiration,pancreatitis,burn
8
Q
criteria for systemic inflammatory response syndrome
A
General variables, altered mental status, inflammatory variables, organ dysfunction, variables, tissue perfusion variables
9
Q
General variables for SIRS
A
Fever(core temp g/t 38.3C Hypothermia l/t 36C HR g/t 90bpm Tachypnea altered mental status edema g/t 20ml/kg over 24hrs hyperglycemia in the absence of diabetes
10
Q
Inflammatory variable for SIRS
A
WBC g/t 12,000 WBC l/t 4000 bandemia g/t 10% plasma C reactive protein g/t 2 s.d plasma procalcitonin g/t 2 s.d
11
Q
What are the risk factors for infection?
A
- Host factors(old age, hyperglycemia)
- Genetics and genomics of trauma and sepsis
- Interactions between the host and therapy
12
Q
medical conditions known to increase risk of post op infection
A
- extremes of age
- malnutrition
- obesity
- DM
- prior sire irradiation
- hypothermia
- hypoxemia
- coexisting infection
- corticosteroid therapy
- recent operation in chest and abdomen
- chronic inflammation
- hypercholesterolemia
13
Q
example of host and therapy interactions
A
*blood transfusion
-altered leukocyte antigen presentation
-shift to T-helper phenotype
control of blood
*glucose concentration
14
Q
ways to prevent and treat of surgical infection?
A
source control
appropriate use of antimicrobial agents
15
Q
consists of drainage of all purulent material, debridement of all site of infection
A
source control
16
Q
- administration of an antimicrobial agents prior to initiation of certain specific typesof surgical procedures to reduce the number of microbes
- 30min- 1 hr prior to incision
A
prophylaxis
17
Q
use of an antimicrobial agents when the risk for surgical infection is high
limited to short course of drug (3-5 days)
A
Emperic therapy
18
Q
evidence of SIRS should lead the surgeon to initiate what therapy?
A
empirical antibiotic therapy
19
Q
initial antimicrobial selection is borad with a later narrowing of agents based on patient response and culture results
A
de-escalation therapy
20
Q
therapy guidelines for UTI, given for how many days?
A
given 3-5 days
21
Q
therapy guidelines for pneumonia, given for how many days?
A
given 7-10 days
22
Q
therapy guidelines for bacteremia, given for how many days?
A
given 7-14 days
23
Q
antibiotic therapy for osteomyelitis, endocarditis, or prosthetic infections is given for how many weeks?
A
6-12 weeks
24
Q
prophylaxis for cardiovascular and thoracic ]procedure, pulmonary resection, lower limb amputation
A
first generation cephalosporins
alternative: gentamicin and metronidazole
25
2nd generation cephalosporins are given for what surgical procedures?
- appendectomy
- colon surgery
- penetrating abdominal trauma
alternative: metro + gentamicin
26
involves the principles of drug absorption, distribution and metabolism
pharmacokinetics
27
the percentage of drug dose that reaches the systemic circulation
affected by absorption, intestinal transit time, and degree of hepatic metabolism
bioavailability
28
reflects clearance and volume
| useful to estimate for the interpretation of drug concentration data
half life
29
derived proportionality constant of no particular physiologic significance that is independent of a drug's clearance
useful for estimating the plasma drug concentration achievable fronm a given dose
volume of distribution
30
volume of liquid from which a drug is eliminated per unit of time, whether by tissue, distribution, metabolism, or elimination
clearance
31
principles in the administration of an antimicrobial agent for prophylaxis
- safety
- appropriate narrow spectrum coverage of relevant pathogens
- little or no reliance on the agent for therapy of infection
- administration within 1 hour before surgery and for a defined brief period thereafter
32
factors influencing antibiotic choice
-activity against known or suspected pathogen
-disease believed responsible
-distinguish infection from colonization
- narro spectrum coverage most desirable
-antimicrobial resistance pattern
-patient specific pattern
institutional guidelines and restrictions
33
cell wall active agents
- Beta lactam antibiotics(Penicillins,Cephalosporins,Monobactans,Carbapenems)
- lipoglycopeptides
- Cyclic lipopeptides
- Polymyxins
34
what drugs are the proteins synthesis inhibitors
- Aminoglycosides
- Tetracyclines
- Oxazolidinones
- Macrolide-lincosamide-steptogramin family(clindamycin)
35
bind to the bacterial 30s ribosomal subunit, inhibiting protein synthesis.
Aminoglycosides
36
bind irreversibly to the 30s ribosomal subunit, but unlike aminoglycosides they are bacteriostatic
active against anaerobes
Tetracyclines
37
protein syntheis inhibitor that is contraindicated for pregnant women and children less than 8 yo
Tetracyclines
38
binds to 50s ribosome subunits
- has good antianaerobic activity and reasonably good activity against susceptible gram+ cocci
- no activity for MRSA
Clindamycin
39
used primarily as therapy for sensitive strains of staphylococci
Penicillins
40
useful for only for prophylaxis, uncomplicated infections or de-escalation therapy when results of susceptibility testing are known.
1st and 2nd generation cepohalosporins
41
include cefoperazone, cefotaxime, cefpodoxime,cefprozil,ceftazidime,ceftibuten, ceftizoxime,ceftriaxone,and locarbacef
-enhanced activity against gram- bacilli but not agains gram+ bacteria or anaerobic bacteria
3rd generation ceophalosporins
42
has a spectrum of activity against gram - bacilli similar to that of 3rd generation cephalosporins
no activity against gram + organism or anaerobes
aztreonam(monobactams)
43
imipenem-cilastatin, meropenem, doripenem and ertrapenem
| has excellent activity against aerobic and anaerobic streptococci, MRSA, and all gram - bacilli
Carbapenems
44
a soluble lipoglycopeptide, bactericidal only on dividing organisms,
susceptible organisms are S, aureus, S. epidermidis, Strep pyogenes, group B strep, S. pneumoniae and C. difficile
Vancomycin(lipoglycopeptides)
45
inhibit bacterial DNA synthesis by inhibiting DNA gyrase which folds DNA into a superhelix in preparation for replication.
Fluoroquinolones
46
inludes ciprofloxacin, levofloxacin, moxifloxacin,
| -most active against enteric gram - bacteria particularly Enterobacteriaceae and Haemophilus spp.
Fluoroquinolones
47
drug that disrupt nucleic acids
Fluoroquinolones
48
what are the cytotoxic antibiotics?
- trimethoprim-sulfamethoxazole
| - metronidazole
49
-active against almost all anaerobes and against many protozoa that parasite human beings.
-has potent bactericidal activity, including
activity against B. fragilis, Prevotella spp
-ineffective
against actinomycosis
Metronidazole
50
ANTIBIOTIC TOXICITIES?
β-Lactam Allergy
Red Man Syndrome
Nephrotoxicity
Ototoxicity
51
Antipseudomonal Antibacterial Agents for Empirical Use
-Piperacillin-tazobactam
-Cefepime,
-ceftazidime
-Imipenem-cilastatin,
meropenem,
-doripenem
-Ciprofloxacin, levofloxacin (depending on local susceptibility patterns)
Aminoglycosides
Polymyxins (polymyxin B, colistin [polymyxin E])
52
Targeted Spectrum antibacterial agents for Empirical Use
| Gram-Positive
Glycopeptide (e.g., vancomycin, telavancin)
Lipopeptide (e.g., daptomycin; not for known or suspected pneumonia)
Oxazolidinone (e.g., linezolid)
53
Targeted Spectrum antibacterial agents for Empirical Use Gram-Negative
Third-generation cephalosporin (not ceftriaxone)
Monobactam
Polymyxins (polymyxin B, colistin [polymyxin E])
54
Antianaerobic agents for Empirical Use
Metronidazole
55
Broad Spectrum agents for Empirical Use
Piperacillin-tazobactam
Carbapenems
Fluoroquinolones (depending on local susceptibility patterns)
Tigecycline (plus an antipseudomonal agent)
56
are infections of tissues, organs, or spaces exposed by surgeons during perfomance of an invasive procedure
surgical site infections
57
are infections of the tissues,
organs, or spaces exposed by surgeons during performance of an
invasive procedure
Surgical Site Infections
58
SSIs are classified into?
incisional and
organ/space infections, and the former are further subclassified into superficial (limited to skin and subcutaneous tissue)
and deep incisional categories.
59
The development of SSIs is
| related to three factors?
(a) the degree of microbial contamination of the wound during surgery; (b) the duration of the procedure; and (c) host factors such as diabetes, malnutrition, obesity,
immune suppression; and a number of other underlying disease
states.
60
class of surgical wound which include those in which no infection
is present; only skin microflora potentially contaminate the
wound, and no hollow viscus that contains microbes is entered
Clean wounds (class I)
61
```
wounds are similar wiht class I, except that a prosthetic device
(e.g., mesh or valve) is inserted
```
Class I D
62
include those in which a hollow viscus such as the
respiratory, alimentary, or genitourinary tracts with indigenous
bacterial flora is opened under controlled circumstances without
significant spillage of contents
```
Clean/contaminated wounds
(class II)
```
63
include open accidental wounds encountered early after injury, those with extensive
introduction of bacteria into a normally sterile area of the body
due to major breaks in sterile technique (e.g., open cardiac
massage), gross spillage of viscus contents such as from the
intestine, or incision through inflamed, albeit nonpurulent tissue.
Contaminated wounds (class III)
64
include traumatic wounds in which
a significant delay in treatment has occurred and in which
necrotic tissue is present, those created in the presence of overt
infection as evidenced by the presence of purulent material,
and those created to access a perforated viscus accompanied
by a high degree of contamination
Dirty wounds (class IV)
65
Clean (class I) wound examples and infection rates
-Hernia repair,
breast biopsy
-1–2%
66
Clean/
contaminated
(class II) wound examples and infection rates
-Cholecystectomy,
elective GI surgery (not
colon)
-2.1–9.5%
67
another Clean/
| contaminated wound examples and infection rates
- Colorectal surgery
| - 4–14%
68
```
Contaminated
(class III) wound examples and infection rates
```
-Penetrating abdominal
trauma, large tissue injury, enterotomy
during bowel obstruction
3.4–13.2%
69
Dirty (class IV) wound examples and infection rates
Perforated diverticulitis,
necrotizing soft tissue infections
3.1–12.8%
70
surgical wounds that can close primarily?
class I and II
71
Surgical wound in which skin closure is associated with high rates of incisional infection
class III and IV
72
management of incisional SSI?
Incision and drainage
antibiotic therapy in significant cellulitits or systemic inflammatory response syndrome
-opne wound allowed to heal by secondary intention, dressings changed 2x/day
73
first step in the treatment of SSIs?
open and examine suspicious portion of the incision and to decide about further surgical treatment
74
occurs when microbes
invade the normally sterile confines of the peritoneal cavity via
hematogenous dissemination from a distant source of infection or direct inoculation. This process is more common among
patients who retain large amounts of peritoneal fluid due to
ascites, and among those individuals who are being treated for
renal failure via peritoneal dialysis.
primary microbial peritonitis
75
Treatment consists of administration of an antibiotic to which the organism is sensitive; often 14 to 21 days of
therapy are required. Removal of indwelling devices, if present
primary microbial peritonitis
76
occurs subsequent to contamination of the peritoneal cavity due to perforation or severe
inflammation and infection of an intra-abdominal organ. Examples include appendicitis, perforation of any portion of the gastrointestinal tract, or diverticulitis
Secondary microbial peritonitis
77
effective
therapy requires source control to resect or repair the diseased
organ; debridement of necrotic, infected tissue and debris; and
administration of antimicrobial agents directed against aerobes
and anaerobes
Secondary microbial peritonitis
78
Patients in whom standard therapy fails typically develop one or more of the following: an intra-abdominal abscess, leakage from a gastrointestinal
anastomosis leading to?
commonly seen in immunocompromised pts
tertiary
| (persistent) peritonitis
79
what is the most common hepatic abscess?
pyogenic abscess
80
hepatic abscess treatment
Small (<1 cm), multiple abscesses should be sampled and treated
with a 4- to 6-week course of antibiotics. Larger abscesses are
generally amenable to percutaneous drainage, with parameters
for antibiotic therapy and drain removal similar to those mentioned previously. Splenic abscesses are extremely rare and
are treated in a similar fashion. Recurrent hepatic or splenic
abscesses may require operative intervention—unroofing and
marsupialization or splenectomy, respectively.
81
infection of the skin and soft tissue that may drain spontaneously or require surgical incision and drainage
furuncles, boils
82
commonly affected sites in skin and soft tissue infections?
extremities, perineum, trunk and torso
83
also knows as dishwater pus
turbid semipurulent material
84
what are the postperative nosocomial infections?
surgical site infections, pneumonia, bacteremia, UTI
85
The presence of a postoperative UTI should be considered
| based on?
urinalysis demonstrating WBCs or bacteria, a positive
| test for leukocyte esterase, or a combination of these elements.
86
diagnosis of symptomatic UTI
>104 CFU/mL of microbes are identified by culture techniques
87
diagnosis of asymptomatic UTI
r >105
| CFU/mL in asymptomatic individuals.
88
develops after 1-6 day incubation period
| characteristic chest roentgenographic findings include a widened mediastinum and pleural effusions
Bacillus anthracis
89
Plague is caused by the gram-negative organism Y pestis.
The naturally occurring disease in humans is transmitted via
flea bites from rodents.
Yersinia pestis (Plague)
90
Individuals who develop a
| painful enlarged lymph node lesion in Yersinia pestis , termed a?
bubo
91
incubation period of 10 to
12 days, clinical manifestations of malaise, fever, vomiting, and
headache appear, followed by development of a characteristic
centripetal rash (which is found to predominate on the face and
extremities).
Smallpox
