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1

Power-Pulsed Lavage article

- Significantly reduces the amount of bacteria

-if it does not hurt go ahead and use it.

2

Patzakis article

-Foot divided into three sections for puncture wounds

-Highest to lowest for development of osteomyelitis:
Zone 1> Zone 2> Zone 3

3

Nail puncture through a rubber soled shoe

- Unsuccessful treatment group more likely to have received antibiotics in the community

-Unsuccessful treatment group waited longer to go to ED

-Gram + bacteria (cover staph)
-Gram - bacteria (cover pseudo)

4

Plantar puncture wounds in Children

Time of presentation:
Day of injury:
-prophylactic tetanus
-cleansing of puncture
-x-ray or sonography

24-36 hours after injury
-hospitalize for parenteral antibiotics
-perform surgery

1 week after injury
-retained foreign body must be removed
-osteomyelitis

Later symptoms
-deeper infections present

5

Hawthorn fragment in a child's foot

-MRI may not be the best mode of visualization, use an ultrasound

6

Definition of SIRS

SIRS= more than one of the following:
-temp extremes
-high HR
-High Resp
-High WBC

7

Definition of sepsis

SIRS+infection

8

Severe sepsis

Sepsis+ organ dysfunction, hypoperfusion abnormality, or sepsis induced hypotension

9

Septic shock

-a subset of severe sepsis

-sepsis induced hypotension

10

MODS

-a continuum where the organ fail to maintain homeostasis

11

Types of fevers (5)

-infection: most common cause

-cytokine-mediated fevers

-central fevers:harm to the thermoregulatory regions of brain

-fever of unknown origin

-drug fever

12

Postoperative fevers (5)

-Day 1: Systemic Inflammatory response syndrome

-Day 2-3: respiratory causes

-Day 3-5: Urinary tract infection

-Day 4-7: wound infection, DVT and acute gout

Day 5-8: drug fever

13

Surgical management of diabetic foot infections

-broad spectrum antibiotics should be prescribed

-need a stepwise approach when it comes to these patients

14

Performing serum inflammatory markers for the diagnosis and follow up of patients with osteo

Inflammatory markers are: CRP, ESR, White blood cells, Procalcitonin.

- They will decline after initiation of antibiotic treatment

-ESR is the best marker used to monitor the response to therapy in patients with osteo. ESR declines in soft tissue infections not osteo

-Using inflammatory markers, particularly ESR with observation will go a long way

15

Acute Phase reactants predict risk of amputations in diabetic foot infections

- post treatment CRP level is a strong predictor of treatment failure and amputation risk in patients with diabetic foot ulcers

16

Value of WBC with differential in acute diabetic foot infection

- diagnosis of infection is made primarily on the basis of clinical signs

-a normal WBC and white cell differential should not deter the physician from taking appropriate action.

17

Angiograms: what do they visualize (3)

-distribution of disease

-length and severity of diseased segments

-demonstrate inflow and outflow vessels

18

Types of angiograms

-Computed tomography angiogram (CTA)

-Magnetic Resonance Angiogram (MRA)

-Digital subtraction Arteriography (DSA)

19

Computed Tomography Angiogram

-IV iodine rich contrast injected.

-CT scanning used

A rapid exam but not good for renal disease and becomes shadowed due to calcification.

20

Magnetic resonance angiogram

Does not require IV contrast (but if it does will use Gadolinium)

-This is a more expensive exam than the rest however gives you a very clear picture

21

Digital Subtraction arteriography

Gold standard

- Will give a superior resolution with lower doses of contrast in real time.

-However will have much higher exposure to radiation

22

CO2

-used as a negative contrast agent in DSA by displacing the blood.

- a great alternative for patients with renal failure or contrast allergy

23

Echocardiograms

-2 types and what are they used for

TTE and TEE

-TTE is a noninvasive procedure , however it may be blocked by body tissues, or scarring

-TEE is much less common and much more invasive. Usually only occurs when good visualization can not be obtained with TTE

24

Tech 99

-binds directly to calcium hydroxyapatite to form soluble salts via osteoblasts

-High sensitivity for low specificity:
---osteomyelitis
---recent surgery
---arthritis
---bone tumors
---fracture
--- ischemic necrosis of bone

25

Gallium-67-

-identifies acute inflammation and infection
through:
---direct bacterial uptake
---phagocytosis of bacterial cells by phagocytes
---direct leukocyte labelling

Sensitive but not specific for acute osteo will also pick up:
--infection
--fractures
-- inflammation
--trauma
--neoplasms
--gout

26

Indium-111

-WBC are isolated from patient's blood and labelled with Indium-111 and reinjected into patient

-Highly sensitive and specific for acute soft tissue and osseous infections

27

Ceretec Scan

Tc-99 labelled WBC

-High sensitivity for acute soft tissue and osseous infections

-Higher specificity for acute osteomyelitis than in In-111

-easier and less radiation than Indium-111, which allows more radioactive material to be used and increased anatomical contrast

28

SPECT/CT

-single photon emisssion CT

-Detects radio-labelled markers and creates an image

-Shows level of biological activity as well

29

What will acute osteomyelitis show on:

-Tc-99m Scan

-Ga-67 scan

-Indium scan

-Ceretec scan

-Tc 99:
---Phase 1: +
---Phase II:++
---Phase III:+++


-Ga-67 scan: positive focal uptake

-Indium Scan: Positive

-Ceretec scan: Positive

30

What will Inactive Chronic osteo show on:

-Tc-99m Scan

-Ga-67 scan

-Indium scan

-Ceretec scan

-Tc-99m Scan
---Phase I: +/-
---Phase II: +
---Phase III: +++

-Ga-67: negative

-Indium: Negative

-Ceretec scan: Negative

31

What will acute cellulitis show on:

-Tc-99m Scan

-Ga-67 scan

-Indium scan

-Ceretec scan

Tc-99m Scan:
---Phase I:+++
---Phase II: ++
---Phase III: +

-Ga-67: Positive diffuse uptake

-Indium: Positibe

Ceretec Scan: Negative

32

Charcot joint:

-Tc-99m Scan

-Ga-67 scan

-Indium scan

-Ceretec scan

Tc-99m Scan:
---Phase I: +/-
---Phase II: +/-
---Phase III: +++
---Phase IV: ++/+++

-Ga-67: Negative

-Indium scan: Negative

-Ceretec scan: Negative

33

Positive Ceretec signifies?

acute osteomyelitis

34

Positive Indium indicates?

either acute osteomyelitis or acute cellulitis

35

Positive Ga-67 scan signifies?

-Positive focal uptake signifies: acute osteomyelitis

-Positive diffuse uptake signifies: acute cellulitis

36

Identifying the incidence and risk factors for reamputation among patients who underwent foot amputation article:

-Risks associated with reamputation

-Higher level amputations

-Longer hospitalization

-Insulin-dependent diabetes

-Gangrene on admission

37

Acute Kidney Injury definition

-abrupt and usually reversible decline in the GFR or decreased urine output within 7 days

-increase in creatinine of .3mg/dL within 48 hours

-50 percent increase in creatinine within 7 days

- decrease in urine volume to <3mL/kg over six hours

Will result in an elevation of BUN, creatinine

38

AKI diagnosis: How to make it

-UA w/ microscopy

-BMP

-Serum and urine protein electrophoresis

-renal ultrasound

39

AKI treatment (4) things

-determine the cause

-remove any active insults

-minimize new injury

-identify the complications

40

Probing to bone in infected pedal ulcers article conclusion

-in hospitalized diabetic patients with limb-threatening infection, palpable bone at the ulcer base by Probe to bone test was significantly associated with underlying osteo.

41

Probe to bone test in a diaetic foot osteo in a clinical setting

-in a clinical setting the PTB test is better used to exclude osteo

-in a hospital setting the PTB test is more helpful in diagnosing osteo

42

Efficacy of MRI in diagnosing diabetic foot osteo in the presence of ischemia

-preoperative MRI effective in diagnosis of neuropathic ulcers

-Preoperative MRI less effective in diagnosis of ischemic ulcers

43

Statistical reliability of bone biopsy for the diagnosis of diabetic foot osteomyelitis article

-results suggest limited reliability of the histopathologic analysis of bone

-histopathologic bone biopsy should not be sonsidered the "standard" of diabetic foot osteo

44

Does this patient with diabetes have osteo of the lower extremity article

-osteo of the foot causes significant morbidity in patients with diabetes

-using the criteria of an ulcer that measures more than 2cm, positive PTB, an ESR greater than 70mm/h, an abnormal x-ray and MRI, along with a detailed history can help improve diagnostic accuracy and improve patient outcomes

45

Primary non surgical management of osteo of the foot in diabetics article

-urgent surgery is indicated in some patients, however non-surgical management of those without limb-threatening infection is associated with a high rate of apparent remission

46

Outcome of diabetic foot osteo treated non-surgically

-Bone culture based antibiotic therapy is an independent factor predictive of remission in diabetic patients with osteo of the foot

-there is also a possible negative effect of nonbone-based antibiotic therapy for osteo of the diabetic foot

47

Rate of residual osteo after partial amp in diabetic patients

-after debridement and irrigation it is recommended to routinely obtain bone margin cultures

- residual osteo has a statistical significant association with poor outcomes

48

Reasons for prophylactic use of antibiotics

-Following wounds

-For surgery

-For prophylaxis against bacterial endocarditis in patient with compromised heart valve

-Dental patients

49

Antibiotics used for prophylaxis (8)

- cefazolin

-cefuroxime

-Ceftriaxone

-Vancomycin

-Clindamycin

-Ciprofloxacin

-Levofloxacin

-Teicoplanin

50

Cefazolin

-use in Lower extremity

-Half life

-coverage

-Doseage

-most frequently used for lower extremity

-longest half-life of any 1st generation cephalosporin

-spectrum: anti-staphylococcal and gram negative

Dosing: 1-2g IV or IM before surgery

51

Cefuroxime

-what type of surgery is it used

-comparison to ancef

-usually used in cardiothoracic surgery

-may have better anti-staph than Cefazolin

52

Ceftriaxone

-half life

-spectrum

-longest half life of any cephalosporin

-relative lack of anti-staph activity

53

Vancomycin

-when is it used

-dosing

-used in penicillin or cephalosporin allergic patients or high MRSA expected areas

-1g IV 12hours.... slow infusion over 1 hour

54

Clindamycin

Use?

Dose:

-useful in implant surgery

-great substitute for vancomcin in beta-lactam allergic patients

-dosing 600-900 mg IV

55

Ciprofloxacin

use:

activity:

very versatile but not used as likely in prophylaxis for lower extremity surgery

-mediocre anti-staphylococcal activity

56

Levofloxacin

coverage:

half life:

Oral vs. IV

-better staph and strep coverage than Cipro

-longer half life

-oral dosing achievable levels are similar as parenteral

57

Joint aspiration:

Uses
----diagnosis vs therapy

Diagnostic:
-used in the evaluation for septic joint

-also used in the confirmation of gouty arthritis

Therapeutic
-injection with steroids for inflammatory condition

-drain effusion to relieve pressure

58

Aspiration of the ankle:

-approaches

Medial approach:
-more common
-leg kept at 90 degrees, insert needle between TA and medial malleolus.

Lateral approach: less common
-between lateral to EDL

59

Aspiration of the MTPJ

steps:

-distract the toe with gentle plantarflexion

-insert needle perpendicularly and into joint space medially

-avoid extensors

60

Synovial fluid analysis

WBC count to keep in mind

<2000WBC/mm3 is noninflammatory

>2000 WBC/mm3 is inflammatory or septic

61

Synovial fluid analysis table

LOOK AT STEVEN's tables

62

Late hematogenous infection of the 1 MTPJ

- It is more common for late hematogenous infections to come from knee and hip replacements.

-This case occured in 1st MTPJ due to misdiagnosis and the administration of steroids

63

Acute hematogenous osteo

-Labs to receive

CBC

ESR and CRP

Blood cultures

64

Acute Hematogenous osteo

Unique infecting organisms in:

-newborns

-children

Newborns: Group B strep

Children: H. influenzae

65

Acute hematogenous osteo treatment options (3)

-Incision and drainage

-cultures

-antibiotics that are tailored toward the infection

66

Pathogens isolated from deep soft tissue and bone in patients with diabetic foot infections

-main finding

Most of the time bone and soft tissue cultures differed

67

Minimum Inhibitory Concentration

-definition

Is the lowest concentration of a chemical which prevents visible growth of a bacterium overnight

68

Minimum Inhibitory Concentration

-Clinical use

used to confirm resistance and to determine in vitro activity of new antimicrobials

69

Minimum Inhibitory concentration

-Interpretation

-antimicrobials with the smallest MIC are the most effective

70

Minimum Inhibitory concentrations

-Breakpoint

-chosen concentration of an antibiotic which defines whether a species of bacteria is susceptible or resistant

-If the MIC is smaller than the susceptibility breakpoint then the bacteria is considered to be susceptible to the antibiotic

71

The role of polymethylmethacrylate antibiotic loaded cement-article

-Three big antibiotics are:
*tobramycin
*gentamycin
*vancomycin

-PMMA provides local delivery of high concentrations that do not depend on vascular support or have systemic toxicity complications

72

Infection control issues

-active surveillance cultures: definition

-Decolonization: definition

Active surveillance cultures:

-universal or targeted microbiological screening cultures for patients admitted to a hospital

-used to try and help control infections


Decolonization:
-a process used in infection control that destroys a resistant organism before it can cause infection and spread by using topical antibiotics and antiseptics

73

C. difficile

Diagnosis

Treatment:

Diagnosis:
-C. difficile infection requires demonstration of C.dif toxins or detection of toxigenic C.dif organisms

-Findings of pseudomembranous colitis are highly suggestive of C.diff


Treatment:
-discontinuation of inciting antibiotic

-Vanc: 125 mg QID PO
-Metronidazole: 500mg QID PO

74

Hospital acquired MRSA

-Buzzwords:

Treatment:

-Older patients
-In a care facility
-With chronic wounds
- Multiple recent antibiotic exposure

-treated: Vanco, Zyvox and Cubicin

75

Community acquired MRSA

-Buzzwords:

Treatment

-Younger patients
-Contain genes: USA300, PVL, SCC mec IV, and cycolytic peptides

Treatment:
-TMP/SMX (bactrim)
-Minocycline and doxycycline

76

How to differentiate between community and hospital aquired MRSA

Clindamycin induced susceptibility