Skin

Question 1

How does antibiotic resistance of MRSI occur

Answer 1

acquisition of mecA gene which encodes a penicillin binding protien (PBP2a) that has a lower binding affinitiy for beta lactams

Question 2

What are risk factors for MRSI

Answer 2

use of fluoroquinolones; IV catheterization; more than 10 vet staff employed; post-surgery site infection

Question 3

What are abx commonly used to treat MRSI

Answer 3

doxycyclyline and chloramphenicol

Question 4

How are burns classified

Answer 4

on body surface area and depth of tissue

Question 5

Describe the total body surface area measurements in adapted to animals

Answer 5

Rule of nines
Head/Neck, each front limb = 9%
Each pelvic limb, dorsal trunk, ventral trunk = 18%

Question 6

What is the severity associated with TBSA in burns

Answer 6

Local burn < 20% less likely for SIRS
Severe burn > 20-30% Very likely SIRS
> 50% TBSA very poor prognosis

Question 7

Describe a first degree burn

Answer 7

Epidermis only

Painful, hyperemic

Question 8

Describe second degree burns

Answer 8

Epidermis and upper portions of dermis: pain, blistering, hair intact
If deeper portions of dermis but not complete can see yellow white skin, lost of hair (pulls out), pain only with deep pressure

Question 9

Describe third degree burns

Answer 9

Epidermis and entire dermis
black letheary skin; eschar is sensitive to touch
Hair pulls out easily

Question 10

Describe fourth degree burns

Answer 10

epidermis and entire dermis, deeper tissues (connective, bone, vessels etc)
Black letheary skin; eschar is sensitive touch
Hair pulls out easily

Question 11

Which burn categorization method has been validated in small animals

Answer 11

None

Question 12

What is the local response to burn

Answer 12

Cells closest to heat source undergo coagulation and vascular thrombosis
Surrounding tissue affected by blood stasis and edema from capillary leak syndrome
Above plus hypoperfusion lead to ischemia

Question 13

How does hypoxia worsen with burns

Answer 13

Edema from hypoalbuminema and vasoactive substances thromboxane and inducible NO worsen hypoxia

Question 14

How long before closure of burn may be considered

Answer 14

Up to 3 days to declare itself, may be up to 7 days.

Question 15

How does frostbite result in injury

Answer 15

Formation of ice crystals resulting in varying degrees of severity similar to burns

Question 16

Describe type 1 hypersensitivity reactions- skin

Answer 16

angiodema, uticaria, erythema

IgE- antigen complex binds to mast cells and basophils

Question 17

Describe type 2 hypersensitivity reactions - skin

Answer 17

Vesicles, bullae, erosions, mucocutaneous junctions
IgM and IgG cytotoxic
antigen-antibody binding

Question 18

Describe type 3 hypersensitivity reactions - skin

Answer 18

Uticaria, ulceration, pitting edema, wheals, papules, pinnae foot pads; MC junctions
IgG immune complexes deposited in endotheilium of vessels

Question 19

Describe type 4 hypersensitivity reactions - skin

Answer 19

Vesicles bullae, papules, plaques, along trunk axilla, inguinal and pinnae
Antigen bound to T-cells result in tissue necrosis and activation of macrophages

Question 20

What are the three types of soft tissue infections

Answer 20

Type 1 Polymicrobial— often MRSA
Type 2 Monomicrobial– often streptococci
Type 3 Anerobic

Question 21

Why are fluoroquinolones not recommended as first line for severe soft tissue infections

Answer 21

In vitro induce bacteriophage-mediated lysis with increase expression of superantigens
1 study 50% were resistant

Question 22

What are the phases of wound healing

Answer 22

Inflammation/debridement
Repair (proliferation
Maturation

Question 23

What occurs in the inflammation/debridement phase of wound healing

Answer 23

First 48-72 hrs
Fills with blood; transient vasoconstriction then vasodilation response to histamine and IL8
Neutrophils initially then macrophages which are essential for wound healing

Question 24

What occurs in the repair (proliferation) phase of wound healing

Answer 24

1-3 weeks
angiogensis, fibroplasia, wound contraction and epithealization
Phase change marked by increase number of fibroblasts
Type III to Type 1 collagen

Question 25

How does contraction occur in the repair phase

Answer 25

Migration of myofibroblasts | Ceases when tension on surround skin equals the contracting forces or when epithealization is complete

Question 26

What are the benifits of granulation tissue

Answer 26

blood supply | increase wounds resistance to infection

Question 27

What occurs in the maturation phase of wound healing

Answer 27

Progressive gain of tissue strength revolves around collagen deposition. Intial portion of phase at 20% after 3 weeks. Generally will only be 70-80% of normal

Question 28

Which tissue may achieve 100% strength

Answer 28

Bladder, Bones

Question 29

What are the types of wound closure

Answer 29

Primary- within a few hours of wounding Delayed primary- within 3 days--- before granulation tissue formed Secondary closure- closure after onset of granulation tissue

Question 30

What are advantages to wound lavage

Answer 30

debride and hydrate

Question 31

What is the recommended method of lavage and what pressure is ideal

Answer 31

8 psi | 35 ml syringe with 19 ga needle

Question 32

What are advantage properities of SSD

Answer 32

anti: Gram - , gram + and candida

Question 33

In Burn resuscitation what can be deleterious

Answer 33

Delay beyond 2 hours ( increase mortality) | Over resuscitation just as bad as under

Question 34

How does burn shock develop

Answer 34

Distrubitive and hypovolemic | IV volume depletion, low pulmonary artery occulusion pressure, elevated systemic vascular resistance and depressued CO

Question 35

How does depressed cardiac output occur with burn injuries

Answer 35

Decreased plasma volume increased afterload, and decreased contractility TNF alpha and impared calcium at the cellular level

Question 36

How does fluid shift after a burn

Answer 36

Protein loss to interstitium as microcirculation is lost Colloid osmotic pressure drops Transient decrease in interstitial pressure by release of osmotic particles moving fluid to interstitium

Question 37

What results due to fluid shifts after a burn

Answer 37

loss of circulationg plasma volume, hemoconcentration, massive edema formation Decreased UOP, depressed cardiovascular function

Question 38

When is the maximal fluid shift after a burn injury occur

Answer 38

at 24 hours

Question 39

What is the formula most widely used to calculate volume resuscitation after a burn

Answer 39

Parkland formulat 4 ml/kg x % TBSA = amount LRS to give in first 24 hrs Give 1/2 over 8 hours then give second have over 1 hours adjust as needed based on UOP

Question 40

What are colloid recommendations for burns in people based on CCM 2009 review article

Answer 40

alubmin increased risk of death Hypertonic saline 4 x increase AKI, 2 x death FFP only if coagulatpathy

Question 41

What is a good way and not good way to estimate fluid volume in burn patients

Answer 41

No truly great way UOP > 0.5 ml/kg/hr, if less generally under resuscitated BAD: HCT- as will often be increased due to protein loss

Question 42

In burn patients what are the benifits of vitamin C

Answer 42

reduced fluid requiremtns, burn tissue water content, decreased ventilator days

Question 43

How does inhalation injury affect fluid requirements

Answer 43

Increase

Question 44

In people how does inhalation injury alter developement of ventilatory associated pneumonia

Answer 44

70% of pateitns develop.... DONT give prophy abx

Question 45

What are preventable complications of burn injuries

Answer 45

hypothermia, compartement syndrome, DVT, heparin induced thrombocytopenia neutropenia, stress ulcers (give prophy), adrenal insufficency

Question 46

How are signs of infection altered with burns

Answer 46

Burn patients have a reset of temp (often higher), increased HR and tachypenia therefore it is not always easy to tell