Dr. Oaks Surgery Lecture

Question 1

How did Dr. Oaks define surgery?

Answer 1

Surgery is the controlled “wounding” of the body (compared to trauma) w/ a resultant cascade of physiologic responses that ultimately result in near-complete healing. This cascade is called the “stress response” which is seen w/ trauma, burns, infection, and surgery

Question 2

Describe the stress response to surgery

Answer 2

The stress response is characterized by increased secretion of certain pituitary hormones and activation of the sympathetic nervous system.

Question 3

Growth Hormone stimulates _____ synthesis, inhibits ________, promotes _______, and inhibits ______ uptake by cells

Answer 3

Growth Hormone stimulates protein synthesis, inhibits protein breakdown, promotes lipolysis, and inhibits glucose uptake by cells

Question 4

The net effect of the stress response of surgery is:

1) …
2) …

Answer 4

1) salt and water retention to maintain cardiovascular stability
2) increased catabolism to provide energy sources

Question 5

Cytokines, particularly _____, _____, and ____ play a major role in the inflammatory response to surgery. They are released from _____, _____, and _____ cells.

Answer 5

Cytokines, particularly IL-1, TNF alpha and IL-6 play a major role in the inflammatory response to surgery. They are released from leukocytes, fibroblasts and endothelial cells.

Question 6

Cytokines work locally to promote wound healing but also have effects on the ______ to increase acute phase proteins (CRP, fibrinogen, alpha2-macroglobulin)

Answer 6

Liver

Question 7

In relatively minor operative procedures, there is minimal disruption to ______ and wound healing occurs without incident

Answer 7

Homeostasis

Question 8

For extensive surgical procedures, severe disruptions in _____ and _____ balance, _____ synthesis, and wound healing may all occur. These may be further complicated by pre-existing co-morbid conditions (diabetes, atherosclerosis, heart failure, etc…) as well as _____ or _____

Answer 8

fluid and electrolyte balance, protein synthesis and wound healing may all occur
anemia or infection

Question 9

Approximately ___% of total body weight is “water weight” roughly distributed as:
Plasma ___%
Interstitial Fluid ___%
Intracellular Fluid ____%

Answer 9

Approximately 60% of total body weight is “water weight” roughly distributed as:
Plasma 5%
Interstitial Fluid 15%
Intracellular Fluid 40%

Question 10

____ is the primary extracellular cation, and _____ is the primary intracellular cation

Answer 10

Na+

K+

Question 11

If you were to administer 1 L of fluid to a pt, where would most of it end up in their body?

Answer 11

Not a whole lot ends up in the intravascular space, a lot goes to the interstitial space (3rd spacing)

Question 12

To maintain homeostasis, one must provide the appropriate fluids and nutrition (preoperatively/perioperatively/postoperatively)

Answer 12

perioperatively

Question 13

The “normal” person consumes about ____ ml of fluid per day (____ ml from oral intake of liquids and ____ ml derived from solid food)
Fluid loss is via urine (____ ml), stool (____ ml) and skin (____ ml) and lungs (____ ml)

Answer 13

The “normal” person consumes about 2,000 ml of fluid per day (1,500 ml from oral intake of liquids and 500 ml derived from solid food)
Fluid loss is via urine (1,200 ml), stool (200 ml) and skin (400 ml) and lungs (200 ml)

Question 14

In the short term, the best measurement of fluid balance is _______

Answer 14

body weight

Question 15

What is a fistula?

Answer 15

An abnormal connection between two spaces

Question 16

Fluid replacement therapy must be coordinated with _____ needs (add in the ___ and ___)

Answer 16

Fluid replacement therapy must be coordinated with nutritional needs (add in the intravenous and enteral intake)

Question 17

Lactated Ringers (LR) is similar in composition to the _____ fluid in the body

Answer 17

Extracellular

Question 18

5% Albumin contains _____, which allows it to remain in the intravascular space longer

Answer 18

colloid

Question 19

How many calories does a surgical patient need?

Answer 19

30 kcal/kg/day (the same as fluid intake)

For a 70 kg male, that works out to about 2,000 kcal/day

Question 20

For adequate wound healing, provide ____ g of protein/kg/day and ____ nonprotein calories per g of nitrogen (____ gm of protein)

Answer 20

For adequate wound healing, provide 1 g of protein/kg/day and 150 nonprotein calories/g of nitrogen (6.25 g of protein)

Question 21

Also remember that (parenteral/enteral) feeding is FAR SUPERIOR to (parenteral/enteral) feeding, and sepsis morbidity is higher in pts who have been fed (parenterally/enterally)

Answer 21

Also remember that (enteral) feeding is FAR SUPERIOR to (parenteral) feeding, and sepsis morbidity is higher in pts who have been fed (parenterally)

Question 22

If a patient is being fed through a NG tube, is it best to consistently administer nutrition hourly, or bolus three times a day? Why?

Answer 22

Bolus TID because we need peaks in insulin to synthesize protein

Question 23

Stomach produces how many liters of gastric secretions per day?

Answer 23

1 L/day

Question 24

What is the Harris Benedict equation for men and women? Why is it important?

Answer 24

Men: BMR = 66 + ( 6.2 × weight in pounds ) + ( 12.7 × height in inches ) – ( 6.76 × age in years )
Women: BMR = 655.1 + ( 4.35 × weight in pounds ) + ( 4.7 × height in inches ) - ( 4.7 × age in years )

a method used to estimate an individual’s basal metabolic rate (BMR) and daily kilocalorie requirements

Question 25

Failure to provide adequate fluid resuscitation results in continued surgical stress with continued _____ and poor ______

Answer 25

continued catabolism and poor wound healing

Question 26

Failure to provide sufficient calorie and protein intake will exacerbate the “starvation” or perioperative catabolic state and further complicate _______

Answer 26

wound healing

Question 27

Almost all wounds heal by (primary/secondary/tertiary) intention

Answer 27

Primary

Question 28

Some wounds that do not heal by primary intention will heal by ______ intention. This may take ____-____ and occasionally the wound never heals

Answer 28

Secondary; weeks-months

Question 29

Rarely, a surgeon will plan on delayed closure of a wound. This is called ______ intention.

Answer 29

Tertiary

Question 30

What are the three phases of wound healing? Describe each (when they start, how long the phase lasts, what results or could cause prolonged time in that phase).

Answer 30

HEMOSTASIS AND INFLAMMATION: begins immediately and lasts for the first few days (prolonged time here: diabetic ulcers) PROLIFERATION: starts after the first few days and lasts for several weeks (prolonged time here: keloid scars) MATURATION: this process begins after 2-3 weeks and lasts several months

Question 31

T/F There is no overlap between the phases of wound healing

Answer 31

False, there is overlap!

Question 32

______ initiates the inflammatory phase with platelet activation and release of cytokines

Answer 32

Hemostasis

Question 33

The initial cells of the inflammatory phase are _____ quickly followed by ____ and _____. Toward the end of this phase, ____ and ____ appear.

Answer 33

platelets; neutrophils and macrophages; fibroblasts and lymphocytes

Question 34

______ are the principle cell involved in the proliferation phase. These cells are activated by the many cytokines released by _____ cells.

Answer 34

Fibroblasts; WBCs

Question 35

In the proliferation phase of wound healing, initially, type _____ collagen is laid down and over time this is replaced by type _____ collagen

Answer 35

III; I

Question 36

During the proliferation phase of wound healing, _____ cells, leading to new blood vessels (granulation tissue), and epithelial cells, forming new skin, are also activated

Answer 36

Epithelial

Question 37

During the maturation phase, there is maturation of the wound collagen with collagen _____ and _____

Answer 37

breakdown and synthesis

Question 38

Scar remodeling continues for up to _____, during which the wound will reach about ___% of its original strength

Answer 38

12 months | 80%

Question 39

______, a specialized type of fibroblast, contain contractile proteins that contract the wound and make it physically smaller (______ intention)

Answer 39

Myofibroblasts; secondary intention

Question 40

What are some local factors that would affect wound healing?

Answer 40

``` Mechanical Injury Infection Edema Ischemia Necrotic Tissue Radiation Effects Hypoxia Foreign Body ```

Question 41

What are some systemic factors that would affect wound healing?

Answer 41

``` Age Nutrition Obesity Trauma Metabolic Diseases Immunosuppression Connective Tissue Diseases Smoking ```

Question 42

The elderly have a higher incidence of ____ dz, _____, ______, _____, and ____ usage that may impair wound healing

Answer 42

The elderly have a higher incidence of cardiovascular disease, diabetes, malnutrition, cancer, and drug usage that may impair wound healing

Question 43

Vitamins ___ and ___ are required for collagen synthesis as well as cofactors such as ___, ___, and ___

Answer 43

Vitamins A and C are required for collagen synthesis as well as cofactors such as zinc, copper, and manganese

Question 44

Obesity may “mask” ______ and are more likely to develop wound infections (fat lacks ______) and are more “difficult” patients in other ways (____, ___, ___)

Answer 44

Obesity may “mask” protein malnutrition and are more likely to develop wound infections (fat lacks a good blood supply) and are more “difficult” patients in other ways (hygiene, ambulation, DVT)

Question 45

________ impairs neutrophil function and may impair fibroblast function as well

Answer 45

Hyperglycemia

Question 46

Other metabolic diseases that negatively affect wound healing include disorders of the ______ and _____ and ______

Answer 46

Pituitary and adrenals and thyroid (hypo-)

Question 47

________ drugs, such as ____, have deleterious effects on wound healing and increase surgical infection rates

Answer 47

Immunsuppressive; Prednisone

Question 48

By quitting smoking for ____ weeks prior to surgery, you can decrease a pt's mortality by ___%

Answer 48

4 weeks; decrease mortality 50%

Question 49

Connective Tissue Diseases that negatively affect wound healing include _____, _____, and ____. These conditions may affect immune function directly and may also be associated with ____ and _____.

Answer 49

RA, SLE, scleroderma; vasculitis and impaired blood flow

Question 50

Smoking induces profound vasoconstriction and reduces skin blood flow by up to ____%. One cigarette creates a vasoconstrictive effect up to ___ minutes. Smokers also have a decreased tissue oxygen of up to ___% Smoke also contains _____ and _____ which impair oxygen delivery to the tissues by _____

Answer 50

40%; 90 minutes; 30%; CO and hydrogen cyanide; hemoglobin

Question 51

Smoking results in _____ cell dysfunction, enhances _____ formation, impairs ______ phagocytic activity. Smokers have lower levels of Vitamin ____ and have reduced levels of ______ synthesis.

Answer 51

Endothelial; thrombus; neutrophil | Vit C; collagen

Question 52

Wounds are usually classified as “superficial” (skin and fat) or “deep” (fascia or intra-abdominal), with superficial consisting of ____% of wounds and deep ___% of wounds.

Answer 52

75%; 25%

Question 53

T/F You should stop abx w/in 48 hours of surgery

Answer 53

True

Question 54

T/F You should clip and not shave the hair from the skin

Answer 54

True

Question 55

What condition is caused by GAS, Staph aureus, Clostridium perfringens, Bacteroides fragilis and Aeromonas hydrophila either alone or in combination?

Answer 55

Necrotizing fasciitis

Question 56

If a pt presents with intense pain that seems excessive to the physical findings, fever, and tachycardia, what should you assume to be present?

Answer 56

Necrotizing fasciitis

Question 57

Necrotizing fasciitis frequently occurs in the (early/late) postoperative period

Answer 57

Early

Question 58

Necrotizing fasciitis frequently occurs in the (early/late) postoperative period

Answer 58

Early (w/in hours)

Question 59

Avoid ______ on any wound closure. ______ leads to ischemia and this leads to wound disruption. Remember to " _____, not ______"

Answer 59

tension; tension; approximate; strangulate

Question 60

What are the 6 types/classifications of sutures?

Answer 60

Absorbable, Non-absorbable Monofilament, Multifilament (Braided) Synthetic, Natural (silk, cat gut)

Question 61

____ or ____ sutures may be beneficial if a wound becomes infected, as you can remove just one and wound is still okay

Answer 61

staples; interrupted sutures

Question 62

_____ or _____ may be useful in uncooperative patients or when scar formation is undesirable

Answer 62

Steri strips; skin glue

Question 63

_____ can be used in almost any location to “stretch” the skin and allow for later “transfer” to adjacent site. These can be preformed (once/multiple times)

Answer 63

Skin expansion; multiple times

Question 64

A ________ skin graft includes the entire epidermis and dermis leaving behind a wound that itself must be closed

Answer 64

Full thickness skin graft

Question 65

_____ skin grafts appear more “normal” whereas ____ skin grafts are often aesthetically unappealing

Answer 65

Full thickness; split thickness

Question 66

A _______ skin graft includes the entire epidermis and part of the dermis leaving behind a wound that can heal itself by epithelial coverage from the surrounding skin and skin appendages (hair follicles and sweat glands)

Answer 66

Split thickness skin graft

Question 67

____ skin grafts are more fragile but have a lower failure rate because they are thinner and have less metabolic demands

Answer 67

STSG

Question 68

______ skin grafts contract with time whereas _____ skin grafts undergo minimal contraction

Answer 68

STSG; FTSG

Question 69

______ skin grafts can cover much greater surface area by “meshing” and site can be re-harvested

Answer 69

STSG

Question 70

Will a wound vac wound become smaller with treatment?

Answer 70

Yes

Question 71

Wound vac healing is comprised of a dressing that is impermeable to _____

Answer 71

bacteria

Question 72

Using a wound vac increases the ______ to a wound, and reduces ____ formation while maintaining a _____ wound environment

Answer 72

blood flow; edema; moist

Question 73

The benefits of using a wound vac include...

Answer 73

Fixes the tissue in place w/ reduced friction and shear forces Removes proteases from wound bed Increases fibroblast proliferation Mechanically contracts wound surface area

Question 74

Two possible antimicrobials that are used in conjunction with wound vac include _____ and _____

Answer 74

silver and iodine

Question 75

When properly used in wound closure, ______ are more precise, consistent and reproducible, faster but more expensive.

Answer 75

staplers

Question 76

T/F Surgery is the coolest thing you will ever do

Answer 76

True :)