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Flashcards in Miscellaneous Deck (113)
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1
Q

William Halstead’s principles

A

1- Gentle handling of tissue
2 - Meticulous haemostasis
3 - Preservation of blood supply
4 - Strict aseptic technique
5 - Minimum tension on tissues
6 - Accurate tissue apposition
7 - Obliteration of deadspace

2
Q

Consequences of protein-calorie malnutrition (PCM)

A

Organ/muscle atrophy
Delayed wound healing
Impaired immune response
Anemia
Hypoproteinemia
Death

3
Q

Diagnosis of Protein-calorie Malnutrition (PCM)

A
  • Weight loss of more than 10% normal body weight
    •Anorexia or hyporexia (i.e., suboptimal intake of nutrients) for >5 days or an expected decrease in nutrient intake of >5 days
    •Increased nutrient loss (e.g., through vomiting, diarrhea, severe wounds, or burns)
    •Increased nutrient needs (e.g., due to trauma, surgery, infection, burns, or fever)
    •History of chronic illness
    •Serum albumin concentration ≤2.5 g/dL
4
Q

Myelogram -  contraindications and possible complications

A

Contraindicated in patients with:
•Suspected inflammatory central nervous system disease
•Elevated intracranial pressure
•Historical or clinical indication of an underlying encephalopathy
•Potential complications
•Seizures
•Parenchymal damage from insertion of the needle
•Transient neurologic worsening
•Permanent neurologic worsening due to inadvertent contrast injection into the parenchyma or the central canal of the spinal cord

5
Q

The two major mechanisms of suture absorption are

A

Enzymatic and hydrolytic

6
Q

Why is catgut coated with chromium?

A

Chromium increases collagen cross linkage, decreasing absorption rate and tissue inflammation

7
Q

The only reasonable uses for catgut

A

Rapidly healing tissues such as mucosa or ligation small vessels.

8
Q

Characteristics of chronic catgut:
Absorption mechanism
Time until complete absorption

A

Absorption mechanism: enzymatic
Time until complete absorption: 2-3 weeks

9
Q

Polyglycolic acid: Dexon
Mechanism of absorption:
Time until complete absorption:
Time until 50% loss of tensile strength:

A

Mechanism of absorption: hydrolysis
Time until complete absorption: 2-3 months
Time until 50% loss of tensile strength: 2-3 weeks

10
Q

Polyglactin 910: Vicryl

Mechanism of absorption:
Time until complete absorption:
Time until 50% loss of tensile strength:

A

Mechanism of absorption: hydrolysis
Time until complete absorption: 2-3 months
Time until 50% loss of tensile strength: 2-3 weeks

11
Q

Poliglecaprone 25: Monocryl

Mechanism of absorption:
Time until complete absorption:
Time until 50% loss of tensile strength:

A

Mechanism of absorption: hydrolysis
Time until complete absorption: 3-4 months
Time until 50% loss of tensile strength: 1 week

12
Q

Polydioxanone: PDS II

Mechanism of absorption:
Time until complete absorption:
Time until 50% loss of tensile strength:

A

Mechanism of absorption: hydrolysis
Time until complete absorption: 6 months
Time until 50% loss of tensile strength: 5-6 weeks

13
Q

Polyglyconate: Maxon

Mechanism of absorption:
Time until complete absorption:
Time until 50% loss of tensile strength:

A

Mechanism of absorption: hydrolysis
Time until complete absorption: 6 months
Time until 50% loss of tensile strength: 4-5 weeks

14
Q

Glycomer 631: Biosyn

Mechanism of absorption:
Time until complete absorption:
Time until 50% loss of tensile strength:

A

Mechanism of absorption: hydrolysis
Time until complete absorption: 3-4 months
Time until 50% loss of tensile strength: 2-3 weeks

15
Q

Potential use for silk suture material; Where should it be avoided

A

Useful for ligation of large vessels because it insights significant addition reaction. Should not be used in infected sites or anywhere tissue reaction may be considered detrimental

16
Q

Strongest of commonly used synthetic suture materials. Commonly used for tendon and ligament repair

A

Polypropylene

17
Q

Properties of nylon suture - expected loss of tensile strength in acid environment, timeframe

A

50% loss of tensile strength in 12 weeks

18
Q

Ultra high molecular weight polyethylene suture With significantly greater strength in three-point banding when compared with 18 gauge steel

A

FiberWire (strongest of all polyblend sutures)

19
Q

Two types of surgical meshes - which one is stronger

A

Woven and knitted - woven meshes are stronger because filaments are packed tightly

20
Q

What is the importance of pore size in the concept of surgical meshes?

A

The presence of too small pores prevents ingrowth of capillaries and fibroblasts, causing encapsulation rather than incorporation

21
Q

Typical site of failure after application of surgical meshes

A

Mesh/tissue interface

22
Q

Most common complications associated with the use of surgical meshes

A

Visceral adhesions, mesh migration/extrusion, fistula formation, infection

23
Q

Do use of linear stapling devices has been associated with a significant decrease in the formation of granulomas if used in this organ

A

Lungs

24
Q

Four motions of the scalpel’s cutting edge

A

Sliding, pressing, sawing and scraping

25
Q

3 forces used when cutting with scissors

A

Closing, shearing and torque

26
Q

Adequate ring instrument grip

A

Tripod grip

27
Q

Interrupted suture patterns utilized in small animals

A

Simple interrupted
Modified Gambee
Three mattress patterns: horizontal, vertical, cruciate

28
Q

The difference between Cushing and Connell suture pattern

A

Both continuous and inverting patterns, however Cushing only includes the dermis (partial thickness) while Connell includes dermis and sub dermis (full thickness )

29
Q

Appropriate cut end length for synthetic suture

A

3 mm

30
Q

Two types of ligatures

A

Circumferential and Transfixation

31
Q

Three main techniques that can be used to augment hemostasis

A

Reduction of blood flow to the affected area

Topical hemostatic agents

Anti-fibrinolytic‘s

32
Q

Approximate time until platelet aggregation

Approximate extra time until clot cross-linked with fibrin matrix

A

30 seconds

2 to 3 minutes

33
Q

Abdominal counterpressure (bandaging) to control hemorrhage -
Evidence? Effectiveness? Precautions and contraindications

A

Shown to improve survival in experimentally-induced hemoperitoneum in dogs but not clinically proven. Human evidence suggests that it might raise intrathoracic and intracranial pressure, so contraindicated in these cases. Must monitor urine output due to possible intraperitoneal hypertension

34
Q

Topical vasoconstrictors

A

Epinephrine, adrenaline, ephedrine

35
Q

Adrenaline dilution for intranasal Epistaxes control

A

1mg/ml

36
Q

Pringle maneuver

A

Temporary occlusion of the hepatic artery and portal vein to control hepatic hemorrhage

37
Q

Vessels that can be occluded on a temporary basis to control hemorrhage/assist with surgery

A

Hepatic artery, carotid artery, renal artery, aorta, femoral artery, caudal vena cava and tumor artery supply

38
Q

Vessels that can be permanently occluded without significant consequences

A

1) Both common carotid arteries, if vertebral artery is preserved and circle of Willis is functional (not in cats)
2)Both jugular veins (not in cats)
3)Brachiocephalic veins
4)Brachial arteries
5)Hepatic veins
6)Femoral arteries
7)Both external iliac arteries
8)Both common iliac veins
9)Both femoral veins
10)left renal vein
11) “Abdominal vena cava caudal to liver, in the case of chronic compression and established collateral circulation or concurrent right nephrectomy”

39
Q

Circle of Willis - importance; difference between dogs and cats

A

The Circle of Willis is the joining area of several arteries at the bottom (inferior) side of the brain. At the Circle of Willis, the internal carotid arteries branch into smaller arteries that supply oxygenated blood to over 80% of the cerebrum.
Cats do not possess a complete anastomotic circle, and thus ligation of the external carotid arteries will lead to cerebral ischemia (fatal).

40
Q

Potential complications associated with the use of tourniquets

A

Hypertension/hypercoagulopathy during use; hypotension, increased fibrinolytic activity (increased bleeding), Reperfusion injury (edema, ischemic tissue damage, nerve damage.

41
Q

Current recommendations for the use of tourniquets intra-op

A

Pneumatic tourniquets are favored over Esmarch; keep pressure around 100 mmHg above systolic pressure or monitor distally using a Doppler to determine the least amount of pressure necessary to stop arterial flow. Maximum times vary from 15 to 30 minutes depending on site

42
Q

Situations in which the exsanguination of the limb is contraindicated prior to the application of a tourniquet

A

Infection or neoplasia

43
Q

What precaution should be taken if a bandage is applied to a limb immediately after a surgical procedure that employed the use of a tourniquet?

A

The bandage must be replaced within 24 hours. Reperfusion injury increases the chance of swelling/postoperative edema which may cause the bandage to become excessively tight and lead to tissue necrosis

44
Q

Three groups of hemostatic agents

A

“• Mechanical hemostatic agents
• Active hemostatic agents
• Hemostatic sealants”

45
Q

Situations in which hemostatic products are contraindicated

A

When blood salvage techniques (autotransfusion) are in use because particles can pass through the 40 µm filters.
Also contraindicated in intravascular spaces doe to the risk of thromboembolism

46
Q

Mechanical hemostatic agents (5)

A

Gelatins, collagens, oxidized cellulose, polysaccharide spheres, wax

47
Q

Gelatin hemostatic agents - Mechanism of action, reabsorption, potential contraindication

A

Swells in the presence of blood and provide a scaffold upon which fibrin can accumulate and support a platelet clot. Does not directly stimulate platelet aggregation (unlike collagen). Absorbed via granulomatous inflammation. Potentially contraindicated within the spinal canal due to volume expansion

48
Q

Collagen hemostatic agents – mechanism of action, mechanism of absorption, potential concerns

A

Act by both mechanic (support of fibrin) as well as direct activation of platelets stimulating more rapid formation of clot. Absorbed by fibroblast remodeling in 8 to 10 weeks. Same concerns as for gelatins - infection, immune reactions, foreign body reactions, swelling.

49
Q

Oxidized regenerated cellulose (Surgicel) – mechanism of action, mechanism of reabsorption, advantages and disadvantages over gelatins and collagen

A

Forms a dense gelatinous clot upon contact with blood; reabsorbed in 2–6 weeks (mechanism unknown), but may lead to the formation of granulomas that may mimic tumors; promotes an acidic environment with broad antibacterial properties; less effective as a hemostatic in comparison to gelatins and collagen, but more suitable for endoscopic surgery.

50
Q

Polysaccharide spheres (HemaBlock, Bleed-XVet) - mechanism of action, mechanism of absorption, precautions

A

The spheres are hydrophilic and concentrate to the solid components of blood by dehydrating it, resulting in stimulation of platelet responses and providing a mechanical barrier. Rapidly metabolized by endogenous amylase is within 48 hours. Increases in volume by 500% so not suitable for confined spaces

51
Q

Bone wax - typical uses, essential complications

A

Maxilectomy, Mandibulectomy, sternotomy; May inhibit bone healing; foreign body reaction; potentially contraindicated in infected sites; difficult to stick in the face of brisk bleeding.
Ostene (Baxter) is a water soluble version which might avoid these issues

52
Q

Thrombin (Factor II) – mechanism of action, main advantage over mechanical agents, potential concerns

A

Utilizes the normal clotting cascade, actively converting endogenous fibrinogen to fibrin and creating a clot. Frequently combined with gelatins to improve efficacy; Typically bovine, human or recombinant, possibly leading to the production of antibodies which may cross react with normal thrombin leading to clotting disorders. Should not be repeatedly used in subsequent surgeries.

53
Q

Alginates – mechanism of action, typical use, contraindication

A

Typically seaweed derived protein combined with calcium or sodium ions. Most commonly utilized as wound dressing, but also has hemostatic affect due to release of calcium ions in contact with saline or body fluids. Not suitable for cavitary use because of foreign body reaction

54
Q

Hemostatic sealant – Fibrin
Mechanism of action, use

A

Completely independent from patient’s normal clotting mechanism, providing both fibrinogen and thrombin to surgery site. still experimental in Vet Med

55
Q

Synthetic sealants - Mechanism of action, potential uses and concerns

A

Directly seals tissues without the need for normal clotting mechanisms; swells significantly and cannot be used in confined spaces; indicated for the open surgical repair of large vessels and resealing of parenchymatous surfaces or Dura

56
Q

Fibrinolysis - importance in the concept of blood clotting; compare dogs to humans; breed prone to delayed bleeding due to increased fibrinolytic activity

A

Process by which a clot is reabsorbed, allowing repair of the vessel wall and reestablishment of patency. Very brisk in dogs compare to humans; greyhounds are predisposed to delayed postoperative bleeding due to altered fibrinolytic activity as far as 3 days post-op.

57
Q

Lysine analog (Tranexamic acid and aminocaproic acid) - potential (reported) uses/advantage?

A

“In a double-blinded prospective randomized study, epsilon-aminocaproic acid was used at 15.6 to 17.5 mg/kg per os TID for 5 days postoperatively in Greyhounds undergoing elective surgery and prevented postoperative bleeding in two-thirds of affected dogs.
Not effective when there is depletion of clotting factors or coagulopathy.

58
Q

Desmopressin (DDAVP) - mechanism of action; most common use; limitations and possible adverse effects

A

Synthetic analog of arginine that stimulates release of Von Willebrand’s factor and Factor VIII from endothelial cells. Effect only lasts a few hours; commonly used for Von Willebrand’ s deficiency-affected patients requiring surgery, dogs on aspirin requiring emergency surgery and immune mediated coagulopathy due to ehrlichiosis.

59
Q

Ethamsylate

A

Oral or IV hemostatic
Improves platelet adhesion and aggregation
Typically used to enhance Desmopressin effects

60
Q

Zeolite (PetClot) - mechanism, uses

A

“Zeolite adsorbs water to concentrate clotting factors and platelets, activates platelets, and releases calcium ions that activate the coagulation cascade.”

“experimental conditions, zeolite was as effective as chitosan dressings in a lethal exsanguinating extremity injury model and has been reported in military trauma patients to be effective in treatment of both intracorporeal and peripheral hemorrhage”
Not to be used internally - concerns over foreign body reaction.

61
Q

Chitosan (Celox)

A

Biodegradable non-toxic carbohydrates derived from shrimp shells; rapidly forms a stable gel like clot independent of clotting factors or the presence of heparin or clotting factors; metabolized by lysoenzymes leaving no trace, so suitable for internal use. Also hypoallergenic and bactericidal.

62
Q

Time between bandage changes for non-infected wound during inflammatory/debridement phase and repaired phase

A

“Time between bandage changes for a noninfected wound treated with a moisture retentive dressing increases from every 2 to 3 days during the inflammatory/debridement phase of wound healing to every 4 to 7 days as the repair phase progresses. ”

Excerpt From
Veterinary Surgery: Small Animal Expert Consult
Spencer A. Johnston VMD, DACVS & Karen M. Tobias DVM, MS, DACVS
https://books.apple.com/us/book/veterinary-surgery-small-animal-expert-consult/id1250368401
This material may be protected by copyright.

63
Q

Guidelines for the removal/replacement of calcium alginate bandages

A

“Calcium alginate should not be removed before it has turned into a gel (which takes 1 or more days) because the nongelled form may adhere to the wound, causing damage when removed.56 If the primary dressing appears to have continued absorptive ability after the tertiary and secondary layers of a bandage have been removed during a routine bandage change, the wound can be rebandaged without removing the primary dressing.”

Excerpt From
Veterinary Surgery: Small Animal Expert Consult
Spencer A. Johnston VMD, DACVS & Karen M. Tobias DVM, MS, DACVS
https://books.apple.com/us/book/veterinary-surgery-small-animal-expert-consult/id1250368401
This material may be protected by copyright.

64
Q

Areas most commonly affected by ischemic bandage injuries in dogs and cats

A

Immediately proximal to the carpus and the tarsus

65
Q

Normal closing arteriolar pressure for skin versus muscles

A

30 mmHg vs 50 mmHg. The skin can be ischemic even with palpable pulses and muscle contraction. That is why skin becomes necrotic prior to muscle a result of an overly tight bandage

66
Q

The effect of bandaging on wounds located on the flexion surface of a joint

A

“With second intention healing, new skin is established over a wound through a combination of epithelialization (whereby epithelial cells migrate over the granulation bed and build new skin) and contraction (which pulls preexisting skin over the wound). The contraction process covers the wound with full-thickness haired skin that is more robust than that created by epithelialization.79,81 For a wound that overlies the flexion surface of a joint, joint immobilization favors epithelialization, and joint movement favors contraction.75 When periwound skin is adequate to close the wound by contraction (and there are no underlying musculoskeletal problems requiring stabilization), the limb should be bandaged in such a way as to allow some joint movement so as to favor healing by contraction and thus robust skin coverage. Proper assessment of available skin is important, because favoring contraction in the absence of adequate periwound skin can lead to contracture, which ultimately restricts joint mobility. Wounds that are near but not over joints generally are not significantly influenced by mobility of adjacent joints.”

67
Q

Time frame for most bandage associated ischemic injuries

A

24 to 48 hours

68
Q

Are penrose drains indicated for the abdominal cavity? Why?

A

“Penrose drains in the abdominal cavity is not recommended because negative intraperitoneal pressure during expiration can cause retrograde flow of air or fluid into the abdominal cavity, passive drainage of the abdomen is generally ineffective, and these drains may interfere with healing of sites of anastomosis”

Excerpt From
Veterinary Surgery: Small Animal Expert Consult
Spencer A. Johnston VMD, DACVS & Karen M. Tobias DVM, MS, DACVS
https://books.apple.com/us/book/veterinary-surgery-small-animal-expert-consult/id1250368401
This material may be protected by copyright.

69
Q

Proper Penrose drain placement

A

“The drain is kept in place by proper closure of tissue layers, with one or two simple interrupted sutures tacking the drain to the skin of the exit hole (see Figure 19.5A), and by bandaging. Additional sutures are not recommended; placing a suture between the proximal end of the drain and the deep tissues creates the risk that the drain may break and a fragment may be left behind when the drain is removed; placing a suture through the skin into the proximal aspect of the drain creates a direct path for bacterial migration into the deepest aspect of the wound. The practice of exiting both ends of a Penrose drain through the skin is not recommended, not only because it is unlikely to increase drainage (which will occur primarily through the more dependent exit “point), but because this technique limits the ability to have a portion of the drain in the deepest aspect of the affected tissue and creates an additional entry site for bacteria or other contaminants. The exception may be drains in the inguinal or axillary area, for which a single exit point can act as a one-way valve that draws in air when the animal moves, creating subcutaneous emphysema. In this case a second more dorsal exit hole may allow air to escape.49”

70
Q

Ways to minimize drain associated infections

A

“The risk for drain-associated infection can be minimized by (1) using the smallest number and size of drains possible (while ensuring effective drainage), (2) choosing a flexible drain (which induces less tissue trauma), (3) using active closed suction drains, (4) removing the “drain as soon as it no longer benefits the patient, and (5) following proper technique, which includes clipping the area around the drain exit site to avoid contamination from hair, using aseptic methods when placing and handling the drain, exiting the drain through a separate incision, and applying a sterile dressing to the drain exit site”

71
Q

Accuracy of needle core biopsies compared to surgical biopsies

A

“Compared to surgically obtained biopsy samples, needle-core biopsy samples result in an equivalent diagnosis in 56% to 94% of cases.5,21”

Excerpt From
Veterinary Surgery: Small Animal Expert Consult
Spencer A. Johnston VMD, DACVS & Karen M. Tobias DVM, MS, DACVS
https://books.apple.com/us/book/veterinary-surgery-small-animal-expert-consult/id1250368401
This material may be protected by copyright.

72
Q

Difference between preferred biopsy sampling site between soft tissue and bone masses

A

“Samples should be taken at the junction of the mass and normal adjacent tissue to maximize diagnostic quality. The biopsy site should be narrow and deep since neoplastic cells are often present deep into the lesion (avoid broad, shallow specimens). This will also assure that the pseudocapsule, if present, is penetrated.

“For bone lesions, the periphery of the lesion should be avoided because this will most likely sample reactive periosteum”

73
Q

Needle core, punch and incisional biopsy‘s compared for accuracy of grading of soft tissue sarcoma cases

A

“It was found that 59% of the pretreatment biopsies were in agreement with the definitive excision histopathology on grade, with 29% underestimating the grade and 12% overestimating the grade on the pretreatment biopsy.”

Excerpt From
Veterinary Surgery: Small Animal Expert Consult
Spencer A. Johnston VMD, DACVS & Karen M. Tobias DVM, MS, DACVS
https://books.apple.com/us/book/veterinary-surgery-small-animal-expert-consult/id1250368401
This material may be protected by copyright.

74
Q

Is the use of automated Trucut advisable and cats? Incidence of this issue? Why?

A

“Automated Tru-Cut biopsy devices should be used with caution in cats undergoing percutaneous liver needle-core biopsy because a 20% mortality rate has been observed due to intense vagotonia”

Excerpt From
Veterinary Surgery: Small Animal Expert Consult
Spencer A. Johnston VMD, DACVS & Karen M. Tobias DVM, MS, DACVS
https://books.apple.com/us/book/veterinary-surgery-small-animal-expert-consult/id1250368401
This material may be protected by copyright.

75
Q

How to proceed if significant hemorrhage is encountered after obtaining a liver biopsy if additional pressure/topical hemostatic agents/electrocautery have failed?

A

“If bleeding cannot be controlled, horizontal mattress sutures may be placed proximal to the cut surface to staunch bleeding.”

Excerpt From
Veterinary Surgery: Small Animal Expert Consult
Spencer A. Johnston VMD, DACVS & Karen M. Tobias DVM, MS, DACVS
https://books.apple.com/us/book/veterinary-surgery-small-animal-expert-consult/id1250368401
This material may be protected by copyright.

76
Q

Can needle core biopsies be used for metal quantitation (liver)?

A

“Use of liver biopsy samples to measure metal concentrations within the liver has been evaluated, and use of needle-core biopsy liver specimens for determining hepatic metal concentrations may not be as useful as wedge specimens due to the heterogeneous concentrations of metals within the liver.18”

Excerpt From
Veterinary Surgery: Small Animal Expert Consult
Spencer A. Johnston VMD, DACVS & Karen M. Tobias DVM, MS, DACVS
https://books.apple.com/us/book/veterinary-surgery-small-animal-expert-consult/id1250368401
This material may be protected by copyright.

77
Q

Correlation between cytology and histopathology on splenic biopsies (percentage of agreement, percentage of partial agreement]

A

“Correlation between cytology and histopathology resulted in complete agreement in 51.4% and partial agreement in 8.6% of samples.”

Excerpt From
Veterinary Surgery: Small Animal Expert Consult
Spencer A. Johnston VMD, DACVS & Karen M. Tobias DVM, MS, DACVS
https://books.apple.com/us/book/veterinary-surgery-small-animal-expert-consult/id1250368401
This material may be protected by copyright.

78
Q

Required conditions for proper sterilization in a gravity displacement sterilizer

A

121°C for 30 minutes, followed by 30 minutes drying time or 132°C for 15 minutes followed by 30 minutes drying time

79
Q

Method by which ethylene oxide sterilize surgical instruments

A

“Ethylene oxide sterilizes by way of alkylation of proteins and nucleic acids, thereby obstructing cell metabolism and reproduction. ”

Excerpt From
Veterinary Surgery: Small Animal Expert Consult
Spencer A. Johnston VMD, DACVS & Karen M. Tobias DVM, MS, DACVS
https://books.apple.com/us/book/veterinary-surgery-small-animal-expert-consult/id1250368401
This material may be protected by copyright.

80
Q

Required conditions (Approximate)for ethylene oxide sterilization

A

1000 mg/L; 85% humidity, 2 to 5 hours

81
Q

Process by which vaporized hydrogen peroxide sterilize surgical instruments

A

Exposure of instruments to hydroxyl and hydroperoroxyl microbicidal free radicals

82
Q

What are the advantages and disadvantages of vaporized hydrogen peroxide sterilization?

A

Non-toxic, non-pollutant, safe for temperature sensitive items

Cannot be used for liquids, powders, linens or cellulose based materials

83
Q

Biological indicator method (type of bacteria) utilized to verify the effectiveness of steam and hydrogen peroxide/Ozone sterilization methods

A

“For steam sterilization the organism is Geobacillus stearothermophilus (formerly Bacillus stearothermophilus) spores contained in an ampule of culture media. The same organism is used for plasma and ozone sterilizers.”

Excerpt From
Veterinary Surgery: Small Animal Expert Consult
Spencer A. Johnston VMD, DACVS & Karen M. Tobias DVM, MS, DACVS
https://books.apple.com/us/book/veterinary-surgery-small-animal-expert-consult/id1250368401
This material may be protected by copyright.

84
Q

Briefly describe the events that transpired between the placement of a cancellus bone graft and development of new bone

A

Transplanted osteogenic cells or undifferentiated mesenchymal cells become Active osteoblasts, secreting osteoid and transplanted trabecular bone. The osteoid is mineralized and forms new host bone in fracture sites. The new bone is also incorporated into the graft into the host bone. Eventually the necrotic cores of trabecular bone are resorbed by osteoclasts, and are totally replaced by host bone. Trabecular bone is remodeled into cortical bone in response to the mechanical environment.

85
Q

Two types of bacteria commonly associated with skin graft infections and how they affect the outcome of skin grafting.

A

BS/P
Beta-hemolytic streptococci and pseudomonads. They produce large amounts of plasmin and proteolytic enzymes that disrupt the fiber seal preventing adequate graft adhesion.

86
Q

What are the afferent and efferent pathways of the oculocardiac reflex? What are the potential consequences? When is it most likely to occur and how is it treated?

A

Monitoring heart rate and ECG is important during ophthalmic surgery because of the potential for initiation of the oculocardiac reflex.1 This reflex consists of a trigeminal (V) afferent and a vagal (X) efferent pathway. Traction on extraocular muscles or pressure applied to the globe can cause asystole or a variety of cardiac arrhythmias, including severe bradycardia, ventricular fibrillation, premature ventricular contractions, and ventricular tachycardia. If this reflex occurs, manipulation of the eye must stop and pharmacologic treatment initiated. For asystole or bradycardia, atropine (0.02–0.04 mg/kg IV) or glycopyrrolate (0.01–0.02 mg/kg IV) should be given. Because atropine has a faster onset and an increased cardiac effect, it is the drug of choice in cases of severe bradycardia or sinus arrest (see Chapter 12). Premedication with glycopyrrolate or atropine (see Table 16.1) can reduce or prevent this reflex but they should be used with caution in animals with cardiac disease or geriatric feline patients who may not tolerate tachycardia. In these cases, having glycopyrrolate or atropine available in the operating room with the appropriate dose already calculated, so that it may be given rapidly IV if necessary, is recommended.

87
Q

What precautions should be taken when performing ocular or eyelid surgery when it comes to tear production?

A

Tear production decreases significantly under general anesthesia. The corneas should be lubricated at a minimum every hour. Decreased tear production can persist for up to 48 hours, so lubrication should be continued at least every four hours during this period.

88
Q

What is the recommended suture material for eyelid surgery?

A

5-0 Polyglactin 910 (Vicryl)
Soft, absorbable

89
Q

For how long should a patient who suffered abdominal trauma be monitored? Why?

A

8 to 12 hours at a minimum, then for 2 weeks. Abdominal hemorrhage may be delayed 3 to 4 hours post trauma. Mesenteric avulsion and biliary tree rupture may not become evident for several days.

90
Q

Is the addition of povidone iodine to the abdominal lavage solution in a case of peritonitis recommended? Justify your answer

A

“Povidone-iodine is the most widely used antiseptic; however, this practice has not shown a beneficial effect in repeated experimental and clinical trials and may be detrimental in animals with established peritonitis because the carrier, polyvinylpyrrolidone, inhibits macrophage chemotaxis. ”

Excerpt From
Small Animal Surgery E-Book
Theresa Welch Fossum DVM, MS, PhD, Dipl ACVS
https://books.apple.com/us/book/small-animal-surgery-e-book/id1367916984
This material may be protected by copyright.

91
Q

What is the typical signalment, etiology , expected labwork abnormalities and prognosis for chronic hepatitis in labrador retrievers?

A

“Chronic hepatitis of Labrador retrievers occurs in middle-aged to older dogs; it causes no or vague clinical signs and is likely associated with copper accumulation. It is more common in female Labradors than males and may be associated with a genetic abnormality in liver copper metabolism, although the exact cause is unknown. Anorexia, hypoglobulinemia, and prolonged partial thromboplastin time (PTT) may be associated with shorter survival; however, the median survival is approximately 1 year, with some affected dogs surviving as long as 8 years.”

Excerpt From
Small Animal Surgery E-Book
Theresa Welch Fossum DVM, MS, PhD, Dipl ACVS
https://books.apple.com/us/book/small-animal-surgery-e-book/id1367916984
This material may be protected by copyright.

92
Q

What are the indications and contraindications for percutaneous core tissue biopsy (needle or TruCut)?

A

Sensitive and specific for focal lesions such as tumors (carcinoma‘s) and lymphosarcoma

Insensitive and unreliable for patients with diffuse hepatic disease such as inflammation, fibrosis, cirrhosis and necrosis.

93
Q

What is the agreement between liver cytology and histopathology in dogs and cats?

A

Low

“False-negative results (missing a diagnosis) are far more common than false-positive results (categorizing a healthy animal as diseased); therefore, if your clinical index of suspicion is high, consider using another technique to biopsy the liver.”

Excerpt From
Small Animal Surgery E-Book
Theresa Welch Fossum DVM, MS, PhD, Dipl ACVS
https://books.apple.com/us/book/small-animal-surgery-e-book/id1367916984
This material may be protected by copyright.

94
Q

What is the concern associated with the use of automated needle biopsy devices in cats?

A

“Complications associated with automated needle biopsy devices occur, particularly in cats. The strong increase in vagal tone due to the force of the automated device may lead to severe bradycardia, weak peripheral pulses, respiratory impairment, loss of consciousness, and cardiac arrest. A semiautomated biopsy needle device for sample procurement may be preferable.

Excerpt From
Small Animal Surgery E-Book
Theresa Welch Fossum DVM, MS, PhD, Dipl ACVS
https://books.apple.com/us/book/small-animal-surgery-e-book/id1367916984
This material may be protected by copyright.

95
Q

How do laparoscopic biopsy punches, 18 gauge and 14 gauge Trucut needles compare when it comes to the amount of hepatic tissue they obtain during a biopsy procedure?

A

18-gauge Tru-Cut will obtain approximately 5 mg of tissue

14-gauge Tru-Cut will obtain approximately 15 to 20 mg of tissue.”

5 mm laparoscopic biopsy “double spoon“ forcep will obtain 45 mg of tissue

Excerpt From
Small Animal Surgery E-Book
Theresa Welch Fossum DVM, MS, PhD, Dipl ACVS
https://books.apple.com/us/book/small-animal-surgery-e-book/id1367916984
This material may be protected by copyright.

96
Q

What size Baker biopsy punch should be used during a Liver biopsy performed via laparotomy? Why?

A

“Baker biopsy punch. The recommended size for collection of at least six to eight portal triads is 6 mm in diameter. ”

Excerpt From
Small Animal Surgery E-Book
Theresa Welch Fossum DVM, MS, PhD, Dipl ACVS
https://books.apple.com/us/book/small-animal-surgery-e-book/id1367916984
This material may be protected by copyright.

97
Q

Define SVF in the context of Stem Cell Therapy

A

“Stromal vascular fraction (SVF) is obtained by use of proteolytic enzymes and centrifugation of adipose tissue (see Fig. 31.12B). This produces a mixture of hematopoietic stem cells, endothelial cell, and adipose derived stem cells. ”

Excerpt From
Small Animal Surgery E-Book
Theresa Welch Fossum DVM, MS, PhD, Dipl ACVS
https://books.apple.com/us/book/small-animal-surgery-e-book/id1367916984
This material may be protected by copyright.

98
Q

Platelet-Rich Plasma can be used to stimulate healing in various tissues. How is this possible? What are the main factors involved?

A

Platelets are among the first cells to migrate to sites of tissue trauma. In addition to their role in hemostasis, they contain growth factors that stimulate tissue healing

PDGF is active in early wound healing, including stimulation of mitogenesis to increase the number of regenerative cells, angiogenesis, and activation of macrophages, which are responsible for wound cleaning and the generation of additional growth factors.

TGF-β accelerates the production of collagen from fibroblasts in the later stages of healing. TGF-β1 and -β2 are active in chemotaxis and mitogenesis of preosteoblasts and stimulate collagen deposition during connective tissue healing and bone formation.

Insulin-like growth factor-I (IGF-1) has been demonstrated to induce proliferation, differentiation, and hypertrophy of multiple cell lines. IGF-1 and IGF-2 increase the number of osteoblasts and appear to accelerate bone formation.

Excerpt From
Small Animal Surgery E-Book
Theresa Welch Fossum DVM, MS, PhD, Dipl ACVS
https://books.apple.com/us/book/small-animal-surgery-e-book/id1367916984
This material may be protected by copyright.

99
Q

How is PRP formed (made)?

A

“PRP is created by centrifugation of autologous blood followed by extraction of the plasma and buffy coat portion, which contain high concentrations of platelets (Figs. 31.13 and 31.14). Several manufacturers have developed devices for the production of PRP, although variations in centrifuge design result in clinically significant differences in the resulting product. “Platelet gels may be subsequently formed from the concentrate by addition of calcium chloride and thrombin. The gel product may aid in limiting the disbursement of the platelets and growth factors.”

Excerpt From
Small Animal Surgery E-Book
Theresa Welch Fossum DVM, MS, PhD, Dipl ACVS
https://books.apple.com/us/book/small-animal-surgery-e-book/id1367916984
This material may be protected by copyright.

100
Q

Name 4 growth factors found in PRP and their observed effect during treatment of tendon injuries

A

“Growth factors found in PRP including TGF-β1, PDGF, VEGF, and EGF increase type I collagen production and tenocyte proliferation.”

Excerpt From
Small Animal Surgery E-Book
Theresa Welch Fossum DVM, MS, PhD, Dipl ACVS
https://books.apple.com/us/book/small-animal-surgery-e-book/id1367916984
This material may be protected by copyright.

101
Q

PRP can be used as a source of TGF-B to stimulate healing of fractures. What effects of TGF are being harnessed with this method?

A

TGF stimulates increased numbers of fibroblasts and preosteoblasts and supports cell differentiation into mature osteoblasts, resulting in increased bone matrix. Additionally, TGF appears to inhibit osteoclast formation and bone resorption. ”

Excerpt From
Small Animal Surgery E-Book
Theresa Welch Fossum DVM, MS, PhD, Dipl ACVS
https://books.apple.com/us/book/small-animal-surgery-e-book/id1367916984
This material may be protected by copyright.

102
Q

Define the term “sessile”

A

Attached directly by a broad base : not pedunculated a sessile tumor. 2 : firmly attached (as to a cell) : not free to move about sessile antibodies.

103
Q

What is the most common site for a congenital accessory spleen in a dog?

A

Gastrosplenic ligament

104
Q

List the five most important functions of the spleen

A

filtering of microorganisms and antigenic particles from the blood
synthesis of immunoglobulin (Ig) G and cytokines of the complement pathway
maturation of newly formed erythrocytes
storage of RBCs and platelets
removal of abnormal and senescent RBCs

Excerpt From
Veterinary Surgery: Small Animal Expert Consult
Spencer A. Johnston VMD, DACVS & Karen M. Tobias DVM, MS, DACVS
https://books.apple.com/us/book/veterinary-surgery-small-animal-expert-consult/id1250368401
This material may be protected by copyright.

105
Q

What percentage of red blood cell and platelet mass can the spleen store in a dog?

A

“The spleen can store 10% to 20% of a dog’s RBC mass and 30% of the platelet mass”

Excerpt From
Veterinary Surgery: Small Animal Expert Consult
Spencer A. Johnston VMD, DACVS & Karen M. Tobias DVM, MS, DACVS
https://books.apple.com/us/book/veterinary-surgery-small-animal-expert-consult/id1250368401
This material may be protected by copyright.

106
Q

What controls splenic contraction? What percentage of stored RBC’s can be moved into the blood pool? By how much (percentage) can the spleen contract?

A

“Physiologic demand mediates splenic contraction via circulating pressors and direct nerve action on splenic smooth muscle, resulting in up to 98% of stored erythrocytes moving into the rapid pool and reducing splenic size to 25% to 50% of normal”

Excerpt From
Veterinary Surgery: Small Animal Expert Consult
Spencer A. Johnston VMD, DACVS & Karen M. Tobias DVM, MS, DACVS
https://books.apple.com/us/book/veterinary-surgery-small-animal-expert-consult/id1250368401
This material may be protected by copyright.

107
Q

What are the 3 most common causes of uniform splenic enlargement in dogs?

A

“bacteremia, low-grade septicemia, and chronic infectious disease in which pathogens and necrotic debris are filtered in the spleen”

Excerpt From
Veterinary Surgery: Small Animal Expert Consult
Spencer A. Johnston VMD, DACVS & Karen M. Tobias DVM, MS, DACVS
https://books.apple.com/us/book/veterinary-surgery-small-animal-expert-consult/id1250368401
This material may be protected by copyright.

108
Q

What are the 4 mechanisms of congestive enlargement of the spleen?

A

“congestive heart failure, portal hypertension, vascular outflow obstruction, or relaxation of the splenic capsule in response to chemical stimuli”

Excerpt From
Veterinary Surgery: Small Animal Expert Consult
Spencer A. Johnston VMD, DACVS & Karen M. Tobias DVM, MS, DACVS
https://books.apple.com/us/book/veterinary-surgery-small-animal-expert-consult/id1250368401
This material may be protected by copyright.

109
Q

Briefly, define lysosomal storage disease

A

An inherited metabolic defect the result in the accumulation of lipids, carbohydrates, or both in various organs, such as the liver and spleen. 

110
Q

What is the gross aspect of the spleen in a patient with splenic amyloidosis?

A

The spleen is uniformly enlarged, firm, pale beige and “waxy” because of stored lipids.

111
Q

What are the three most common causes for localized splenomegaly in dogs?

A

Nodular hyperplasia

Splenic hematoma

Hemangiosarcoma

112
Q

What are the four cell types often encountered within the nodules in a case of nodular splenic hyperplasia?

A

Lymphoid

Erythroid

Myeloid

Megakaryocytes

113
Q

What is the appropriate temperature for abdominal fluid lavage?

A

“Temperature recommendations for lavage solution vary, with 37°C to 39°C (98.6°F to 102.2°F) most commonly reported”

Excerpt From
Veterinary Surgery: Small Animal Expert Consult
Spencer A. Johnston VMD, DACVS & Karen M. Tobias DVM, MS, DACVS
https://books.apple.com/us/book/veterinary-surgery-small-animal-expert-consult/id1250368401
This material may be protected by copyright.