SSI & Source Control
Hospital-Acquired Infections

(+Question from Mussa)
Wound Care- Biology
Operative/ Wound Care
Previous Lectures :)
100

What hair removal method is employed in the OR

Hair clipping

100

This C. difficile test detects the toxin genes but cannot reliably distinguish active infection from colonization.

PCR/NAAT

100

What are the 4 phases of normal wound healing           

Hemostasis → inflammation → proliferation → remodeling


100

What are the three ways a wound can heal based on how it is closed?

Primary intention, secondary intention, and tertiary intention/delayed primary closure.

100

This medication reverses unfractionated heparin

Protamine

200

During wound exploration, necrotic tissue is identified. Debridement should continue until reaching this type of tissue...

healthy, bleeding tissue

200

Before testing for C. difficile, the patient should generally have at least this many unformed stools within 24 hours.

3 unformed stools

Bonus- what needs to be discontinued for 24 hrs before testing for C. diff?

200

Which cells predominate early in the inflammatory phase, and which cells subsequently become the major coordinators of wound healing?


Neutrophils first, followed by macrophages.

200

You perform a laparotomy for perforated diverticulitis with gross feculent contamination. How would you classify the wound?

Dirty/infected (Class IV)

200

Refractory hypokalemia should prompt you to check and replace this electrolyte

Mag

300

POD 6 after an open colectomy, a patient has erythema and a small amount of purulent drainage limited to the skin and subcutaneous tissue. What would you do?

open and drain the wound

300

This organism is particularly associated with CLABSI in ICU patients receiving TPN

Candida

300

A postoperative wound looks normal externally on POD7. Has it regained its normal tensile strength?

                                               

No. Early wounds remain mechanically vulnerable despite epithelial closure. During remodeling, collagen is reorganized, and type III collagen is progressively replaced by predominantly type I collagen. Even a mature scar reaches only approximately 80% of the tensile strength of normal tissue

300

Your patient's laparotomy incision has a small amount of purulent drainage. What is the most important principle of management?    

Source control. An infected superficial incision generally needs adequate opening/drainage when indicated rather than simply escalating antibiotics. Determine whether infection is superficial, deep incisional, or organ/space and whether deeper imaging or drainage is required. CDC surveillance similarly separates SSI according to depth.

300

A massively transfused trauma patient becomes hypotensive with prolonged QT and decreased contractility. This electrolyte abnormality should be suspected.

hypocalcemia

400

What is the STOP-IT trial?

This landmark trial showed that after adequate source control for intra-abdominal infection, about 4 days of antibiotics produced outcomes similar to continuing antibiotics until 2 days after resolution of fever and ileus.

400

What should you give for fulminant C. diff infection with ileus 

Oral vancomycin + IV metronidazole + Vancomycin enemas 

400

Why does a hematoma increase the risk of poor wound healing and infection? Give at least three mechanisms

 A hematoma:

1. Creates dead space.
2. Separates tissue planes and interferes with normal tissue approximation. 

3. Can increase local pressure and compromise microvascular perfusion. 

4. Provides a protein-rich environment in which bacteria can proliferate.

Operative implication: meticulous hemostasis is part of wound management—not merely control of blood loss.

400

On POD6 after a laparotomy, the skin separates and you can see bowel beneath the incision. What complication should you assume until proven otherwise, and what should you do?

Fascial dehiscence/evisceration — a surgical emergency. Cover exposed viscera with sterile saline-moistened material, keep the patient NPO, resuscitate as needed, immediately involve the senior resident/attending, and prepare for urgent operative management.                

Follow-up: Why isn't closing the skin at bedside appropriate?    

400

A low TEG alpha angle suggests dysfunction of this component.

What do you treat it with?

Fibrinogen 

Cryoprecipitate 

500

A patient undergoes surgery in the setting of an established infection with fecal contamination. What is this wound classification? What is the risk of infection?

Class IV — Dirty/Infected

7-40%

500

From Mussa:

A hospitalized patient has an uncomplicated bloodstream infection with appropriate antimicrobial therapy and adequate source control. The team plans 14 days of antibiotics. What shorter duration has been shown to be non-inferior? What is the name of the trial?

A. OVIVA / B. STOP-IT / C. BALANCE / D. POET / E. MERINO


7 days

BALANCE trial demonstrated that 7 days was noninferior to 14 days for hospitalized patients with bloodstream infection

500

A diabetic smoker has a chronic lower-extremity wound with dry black eschar. Despite repeated topical treatments and dressing changes, it does not heal. What fundamental wound-healing problem must you investigate before simply debriding it?

Perfusion/ischemia.
A wound needs adequate oxygen delivery for fibroblast activity, collagen synthesis, angiogenesis, immune function, and ultimately tissue repair. Debriding an ischemic wound without understanding whether it can heal may simply create a larger nonhealing defect. 

Bonus:

What do you examine? 

What bedside study might you obtain? 

500

POD5 after colectomy, a patient develops fever, tachycardia, worsening abdominal pain, and purulent drainage from the midline incision. You open the superficial wound and drain pus, but the patient remains septic. What is the key mistake if you stop there?

Assuming the visible wound explains the entire infection.
You must consider a deep incisional or organ/space SSI, particularly an intra-abdominal abscess or anastomotic complication. CDC SSI classification specifically distinguishes superficial incisional, deep incisional, and organ/space infection.                                              

Next steps: resuscitation, appropriate antimicrobial therapy, labs, cross-sectional imaging when the patient is stable enough, and definitive source control through percutaneous drainage or operation as dictated by the underlying process.

500

This liver segment is the inferior segment of the right anterior section

Segment V