MGMT Of Traumatic Wounds- Fundamentals

Question 1

4 stages of wound healing?

Answer 1

1. Inflammatory phase
2. Debridement phase
3. Repair
4. Maturation/remodeling phase

Question 2

What phase of wound healing is characterized by:
Increased permeability of local blood vessels,
Recruitment of circulatory cells,
Release of growth factors/cytokines,
Activation of neutrophils, lymphocytes, fibroblasts, and MFs

And is 0-5 days….

Answer 2

Inflammatory

Question 3

What initiates the debridement phase?

Answer 3

WBCs leaking from blood vessels into wounds;

Specifically, the arrival of neutrophils (~6hrs post-wound) and monocytes (~12 hrs)

Question 4

What is the major secretory cell most essential for wound healing?

Answer 4

Monocyte! Synthesize growth factors that participate in tissue formation and remodeling

Question 5

What cells stimulate monocytes?

Answer 5

Neutrophils

Question 6

What phase is associated with the development of an exudate rich in WBCs, wound fluid, and necrotic tissue within a wound bed?

Answer 6

Debridement Phase

Question 7

What cell type:

1. Secretes collagenases (removing dead tissue, bacT, etc)
2. Secretes chemotactic and growth factors (complement, endotoxins, TGF-alpha/beta, IL-1, etc)
3. Recruit mesenchymal cells, stimulate angiogenesis, and modulate matrix production in wounds

Answer 7

Macrophages

Question 8

Where does Basic Fibroblastic Growth Factor (BFGF) comes from and what is its role?

Answer 8

Macrophages/Monocytes, T-lymphs;
* Promotes angiogenesis, granulation, epithelization via endothelial cell, fibroblast, and keratinocyte migration (respectively) *

Question 9

Where does vascular endothelial cell growth factor (VEGF) come from and what is its role in wound healing?

Answer 9

Endothelial cells! Promotes angiogenesis during tissue hypoxia

Question 10

Where does Epidermal Growth Factor come from and what is its role in wound healing?

Answer 10

From Platelets and macrophages;
Stimulates fibroblasts to secrete collagenase to degrade the matrix during the remodeling phase. Stimulates keratinocyte and fibroblast proliferation

Question 11

Where does TGF come from and what is its role in wound healing?

Answer 11

Macrophages, Platelets, Lymphs, and Hepatocytes;

Attracts neutrophils/macrophages, promotes angiogenesis, up-regulates collagen production, and inhibits degradation

Question 12

Where does Keratinocyte Growth Factor (KGF/ aka Growth Factor 7) come from and what is its role in wound healing?

Answer 12

Fibroblasts;

Stimulates keratinocyte migration, differentiation, and proliferation

Question 13

Where does Platelet-Derived Growth Factor (PDGF) come from and what is its role in wound healing?

Answer 13

Platelets, macrophages, endothelial cells;
Attracts neutrophils/macrophages,
Promotes collagen and proteoglycan synthesis

Question 14

In the Repair Phase (3-5 days to 2-4 weeks), what do macrophages stimulate?

Answer 14

Fibroblast and DNA proliferation

Question 15

What does the combination of fibroblasts, new capillaries, and fibrous tissue development result in?

Answer 15

Bright red, fleshy GRANULATION TISSUE! (3-5 days after wounding…)

Question 16

Granulation Tissue is an excellent barrier to infection, provides a surface for epithelial migration, but also serves as a source of special fibroblasts, used in wound contraction - what are they called?

Answer 16

Myofibroblasts

Question 17

When does epithelialization begin in sutured wounds?

Answer 17

24-48 hours

Question 18

When does epithelialization begin in an open wound?

Answer 18

Within 4-5 days

Question 19

During wound contraction of the Repair Phase, what is the approximate rate of progression (mm/day)?

Answer 19

0.6–0.8mm/day

Question 20

What is the approximate rate of granulation tissue formation at each wound edge during the Repair Phase (mm/day)?

Answer 20

0.4-1mm/day

Question 21

What is the “Golden Period” within wounding, where there’s insufficient microbial replication to cause infection and can usually manage with primary closure?

Answer 21

Within 0-6 hours!!!

“Class 1” - minimal contamination or tissue damage

Question 22

What class of wound would microbial replication be at critical level allow for infection (>12 hours of wounding)?

Answer 22

Class 3 :(

Question 23

What type of wound management should we use for Class 1 (and some 2) wounds?

Answer 23

Primary closure (1st intention)

Question 24

What type of wound management would involve appositional closure before granulation tissue develops (w/in 3-5 days of wounding)? Good for Class 2 wounds…

Answer 24

Delayed Primary

Question 25

What type of wound management involves appositional closure after granulation tissue as developed (>3-5 days after wounding)?

Answer 25

Secondary Closure

Question 26

What type of wound management involves healing by contraction/epithelialization and open wound management (OWM)?

Answer 26

Second Intention Healing

Question 27

What ratio of chlorhexidine (To water?) should you use as a lavage solution at 0.05%?

Answer 27

1:40

Question 28

What ratio of povidone-iodine (to water?) should you use as a lavage solution at 0.1%?

Answer 28

1:100

Question 29

What is the historic standard recommended technique for initial wound irrigation?

Answer 29

Use of a 35-mL syringe and 18G needle and pressure from 7-8 psi

Question 30

What pressure adequately REDUCES bacT contamination from wounds?

Answer 30

1.6 psi

Question 31

What pressures can cause barotrauma?

Answer 31

Pressures >25 psi

Question 32

What is the most consistent technique for generation of 7-8 psi in wound flushing?

Answer 32

1L Saline solution bag placed in a pressure cuff at a cuff pressure of 300 mmHg