1. John Pender, MD BSOM, East Carolina University April 1, 2005
Surgical Infection
John Pender, MD
BSOM, East Carolina University
April 1, 2005

3. SSI
Superficial
Deep
Organ/space

7. Soft tissue/wound Third most reported nosocomial infections
16% of all reported nosocomial infections
Most common surgical patient nosocomial infection (38%)
2/3 involved surgical incision, 1/3 deep structures accessed by incision
Deaths in patients with nosocomial infections—77% related to infection.

8. SSI
$3,152 in extra charges
1980 extra ten days of hospitalization
12%-84% present after discharge
Most present within 21 days

9. Risk factors for SSI Diabetes Nicotine Steroids Malnutrition
Length of preoperative hospitalization
Nares colonization Staph Aureus
Perioperative transfusion

10. Preop Scrub Skin prep Hair removal Antiseptic showering
10 or 2 min ? With what?
Skin prep
Iodophors, chlorahexadine, or ETOH
Hair removal
Night before? NO (5% vs .6%)
Antiseptic showering
Reduce skin flora only

11. Antimicrobrial prophylaxis
Clean contaminated procedures
Vascular cases
Cardiac cases
Orthopedic prosthetic cases
Second generation cephalosporin for distal intestinal tract
Timing

12. Class I (clean)
Atraumatic wound w/o inflammation. No respiratory, GU,GI,or biliary tract entered
Hernia repair
? infection rate

13. Class I (clean)
Atraumatic wound w/o inflammation. No respiratory, GU,GI,or biliary tract entered
Hernia repair
1.5% infection rate

14. Class II(clean/contaminated)
Controlled entrance into respiratory, GU,GI,or biliary tracts
Cholecytectomy, elective bowel resection
? infection rate

15. Class II(clean/contaminated)
Controlled entrance into respiratory, GU,GI,or biliary tracts
Cholecytectomy, elective bowel resection
7.5% infection rate

16. Class III(contaminated)
Traumatic wounds, major breaks in sterile techniques, gross spillage of GI contents, Acute non-purulent inflammation
Appendectomy
? infection rate

17. Class III(contaminated)
Traumatic wounds, major breaks in sterile techniques, gross spillage of GI contents, Acute non-purulent inflammation
Appendectomy
15% infection rate

18. Class IV (dirty)
Old trauma wounds; devitalized tissue; existing clinical infection, perforated viscera.
Hartmann’s for diverticular perforation
? Infection rate

19. Class IV (dirty)
Old trauma wounds; devitalized tissue; existing clinical infection, perforated viscera.
Hartmann’s for diverticular perforation
40% infection

20. Merely a flesh wound

21. 50 y.o. obese, diabetic in ED
Heroic MD lanced a small infected “cyst” on the patient’s labia two days ago. Despite MD’s efforts, the erythema has developed and she now has “dishwater” drainage from the area that has a foul odor.

22. Necrotizing Soft Tissue Infection
Debridement/Resuscitation
Debridement
Antibiotics
Nutrition
1.5 to 2 times basal requirements
Treatment delays are predictive of adverse outcome

23. Antibiotic therapy for NSTI
Penicillin and aminoglycoside
Clindamycin or metronidazole
+/- Vancomycin
Alternative: unasyn/zosyn
Silvadene slury

24. Necrotizing Soft Tissue Infection
Mortality rate as high as 40% (17%)
Impaired immune system
Compromised tissue blood supply
Microorganisms (Polymicrobial)
“skin poppin’” or “muscling”
1/3 dibetics
90% comorbid conditions

28. Run away?

29. Hydradenitis suppurativa
Infection of apocrine sweat glands
axilla, groin, perineum, any skin fold
Single abscess treated by I&D
Doxycycline 100mg BID
Excision with STSG (15%)

30. 50 y/o diabetic s/p AAA repair
Presents w/ fever, leukocytosis and an erythematous left groin.

32. Infected Vascular Graft
Inguinal incision is independent risk factor
Length of case and blood loss
0.5% to 5%
Prosthetic HD grafts 10%-20%
S. Aureus
Extracellular glycocalyx
Negative culture

35. 50 y/o diabetic with 2 & 3 degree burns
Develops full thickness necrosis of second degree areas a few days later
Third degree burn eschar unexpectedly separated, revealing hemorrhagic discoloration of the sub eschar fat.

36. Burn Infections Necrotic tissue readily colonized
High bacteria counts are NOT a reliable indication of an infected burn
Histological examination to determine invasiveness
TX: debridement and antibiotics

37. 50 y/o diabetic in rehab
presents with rust colored fluid draining from stump. Extremity is edematous and has some associated erythema.

40. Gas gangrene Beta hemolytic strept
Clostridial perfringes (gram pos rods)rare
50% polymicrobial
Rapid lyses of tissues w/ relatively little response from host
Endotoxin

41. Gas gangrene
Aggressive debridement & antibiotics
Repeat antibiotics

42. Catheter Sepsis
80% of cases, colonized catheters had been inserted by inexperienced and experienced residents
Key is to identify before sepsis develops
Multilumen, number of manipulations, occlusive dressing
Stapylococcus epidermis, S. Aureus, yeast

43. True /False gram negative sepsis
Endotoxin is the lipopolysaccharide component of gram positive bacterial cell walls
Endotoxin triggers release of IL-, IL-6, and TNF from macrophages
Lipid A region is primary initiator of sepsis
Antibodies directed at TNF may be beneficial

44. True /False septic shock
Endotoxin is the lipopolysaccharide component of gram positive bacterial cell walls
Endotoxin triggers release of IL-, IL-6, and TNF from macrophages
Lipid A region is primary initiator of sepsis
Antibodies directed at TNF may be beneficial

45. Gram-Negative Sepsis E.coli, pseudomonas, klebsiella, Enterobacter
>30% mortality
13 cases per 1,000 hospital admissions
Hypotension, hypoxia, acidosis, compliment and coagulation cascade activation
Lipopolysaccharide (LPS)/ endotoxin

46. Gram-Negative Sepsis 6ml/kg, plateau <30, good oxygen delivery
Resuscitation
SVO2
Daily breathing trials
Sedation protocol
SUP
DVT prophylaxis
Xigris
reduces microvascular dysfunction by reducing inflammation and coagulation, and increasing fibrinolysis.
Recombinant Protein C

48. It's pretty much my favorite animal. It's like a lion and a tiger mixed... bred for its skills in magic.

50. Which one of the following are/is characteristic of Tetracyclines
A. Bactericidal
B. activity against Mycobacterium tuberculosis
C. Discoloration of teeth
D. Risk of Superinfection
E. Narrow spectrum

51. Which one of the following are/is characteristic of Tetracyclines
A. Bactericidal
B. activity against Mycobacterium tuberculosis
C. Discoloration of teeth
D. Risk of Superinfection
E. Narrow spectrum

52. Tetracyclines Most Gram positives Many gram Negatives
Alters Ribosomal protein synthesis
Bacteriostatic

53. Which one of the following are/is characteristic of Aminoglycosides
A. Active against a broad spectrum of Gram negative Aerobes
B. Emergence of Resistant bacterial strains does not occur
C. narrow margin between therapeutic and toxic levels
D. nephrotoxicity
E. Ototoxicity

54. Which one of the following are/is characteristic of Aminoglycosides
A. Active against a broad spectrum of Gram negative Aerobes
B. Emergence of Resistant bacterial strains does not occur
C. narrow margin between therapeutic and toxic levels
D. nephrotoxicity
E. Ototoxicity

55. Aminoglycosides Pseudomonas resistance developing 30s ribosome binding
Oxygen dependent step therefore no anaerobic activity

56. Inhibits cell wall synthesis
A. Amphotericin B
B. Penicillin
C. Cephalosporins
D. Aminoglycosides
E. Quinolones

57. Inhibits cell wall synthesis
A. Amphotericin B
B. Penicillin
C. Cephalosporins
D. Aminoglycosides
E. Quinolones

58. Impairment of bacterial DNA synthesis
A. Amphotericin B
B. Penicillin
C. Cephalosporins
D. Aminoglycosides
E. Quinolones

59. Impairment of bacterial DNA synthesis
A. Amphotericin B
B. Penicillin
C. Cephalosporins
D. Aminoglycosides
E. Quinolones

60. Disruption of membrane barrier function
A. Amphotericin B
B. Penicillin
C. Cephalosporins
D. Aminoglycosides
E. Quinolones

61. Disruption of membrane barrier function
A. Amphotericin B
B. Penicillin
C. Cephalosporins
D. Aminoglycosides
E. Quinolones

62. Disruption of ribosomal protein synthesis
A. Amphotericin B
B. Penicillin
C. Cephalosporins
D. Aminoglycosides
E. Quinolones

63. Disruption of ribosomal protein synthesis
A. Amphotericin B
B. Penicillin
C. Cephalosporins
D. Aminoglycosides
E. Quinolones