The document defines wounds and describes the phases and processes of wound healing. It classifies wounds as open or closed and discusses various types of open wounds like incised, lacerated, and penetrating wounds. It also outlines the cells and factors involved in wound healing, potential complications, and treatments for different wound types like surgical/aseptic wounds, contaminated wounds, and accidental traumatic wounds. Treatments include cleaning, debridement, drainage, antibiotics, and closure techniques. Abscesses and hematomas are also discussed.

1. Wounds
VSR-411

2. Definition
Wounds
• A wound is an injury to the body by physical
means that results in disruption of the continuity
of the body structure. The injury may be
intentional i.e. surgical wounds, or accidental, as
in trauma.
or
• A wound may be defined as discontinuity or
separation of skin, mucous membrane or tissue
surface caused by physical, chemical or
biological insult.

3. • Wound healing is a term used loosely to
describe the host mechanisms involved in
the process of restoring the continuity of
the tissues. Wound repair involves
several basic mechanisms including
• a) Angiogenesis
• b) Deposition of connective tissue matrix
• c) Epithelialization
• d) Wound remodeling and contraction

4. Phases of wound healing
• First phase
a) Stage of inflammation
b) Destructive stage
• Second phase
a) Stage of epithelialization
b) Stage of fibroplasia
c) Stage of wound contraction
• Third phase
a) Wound remodelling

5. Cells Involved in Wound
Healing

6. • Classification of wounds
• A wound can be classified broadly into
two main categories ie open and closed.
In open or external wound, there is
discontinuity in the skin or other covering
tissues to a varying depth. In closed or
interstitial wound, only deeper tissues
barring the skin or mucous membrane
are damaged.

7. • Open wounds
• These types of wounds and symptoms for diagnosis can further be
subdivided into different categories.
• Incised wound
• These wounds are caused by sharp objects and there is minimum loss of
tissue.
• Lacerated wound
• These wound are caused by tearing of tissues. Such wounds have irregular
jagged borders e.g. wounds caused by barbed wires. The loss of tissues is
limited to the skin and subcutaneous tissues.
• Penetrating wound
• Penetrating wounds are caused by long pointed objects and may
communicate with body cavities resulting in deep seated infection like
peritonitis and empyema.In animals such wounds caused by horns are
common and are also called gored wounds
• Gunshot wound
• Such wounds are caused by firearms, the degree of tissue damage
depends on the speed of the bullet, and therefore depending on speed the
wound may be incised, lacerated, or contused.

8. • Poisoned wound
• Different types of poisons from plant or chemicals or animal origin may cause wound.
• Bite wound
• Various forms of bites,ie snake identified by fnag marks, dog bite, insect , bees etc
may cause wound.
• Virulent wounds
• Such wounds are caused by viruses or bacteria leading to formation of pustules or
vesicles, eg FMD, Anthrax etc
• Ulcerative wounds
• These are wounds in which excavation of the surface is produced by sloughing of
necrotic tissue and debris. Ulceration of extremities in case of varicose vein is due to
venous stasis, decubitus ulcers, ischemic necrosis of skin due to underlying bony
prominences etc.
• Erosive wounds
• These are wounds, in which there shallow area of necrosis is confined only to
epidermis, healing usually occurs without scar formation.
• Punctured wounds
• These wounds are usually deep and are caused by sharp or blunt objects; such
wounds are prone to anaerobic infections.

9. • Closed or Internal wounds
• These types of wounds can further be subdivided into two categories:
abrasion and contusions.
• Abrasions: Abrasion is an area of body denuded of skin or mucous
membrane. Since injury is superficial, special surgical care is not required
unless extensive area is involved.
• Contusion or bruises: In these wounds there is injury to the skin but
without any break or gap in the continuity of the tissue surface. Some other
tissues like muscles, tendons, bones, and nerves may be involved and
haematoma and subcutaneous edema and infection may be associated with
injury. Contusions can be divided into three types depending on type of
injury and tissues involved.
• First degree contusion: There is rupture of capillary vessels of the skin
and subcutaneous tissues to form ecchymosis.
• Second degree contusions in which larger vessels are ruptured leading to
the formation of a haematoma.
• Third degree contusions in which the tissues are considerably damaged
and gangrene may set in.

10. Factors affecting wound healing
Local Factors
• Surgical technique
• Tissue vascularity
• Mechanical stress
• Motion
• Edema and dehydration
• Necrotic tissue
• Foreign body
• Infection
• Sutures
• Irradiation
• Area of wound
• Bandages

11. • Systemic factors
• Age
• Obesity
• Malnutrition
• Vitamin deficiency
• Trace elements
• Anemia and Hypoxia
• Systemic diseases
• Temperature
• Anti inflammatory drugs

12. Complications of wound healing
• Hemorrhage
• Wound Dehiscence
• Traumatic Neuralgia
• Traumatic septicaemia
• Traumatic Emphysema
• Tetanus
• Haematoma
• Sinus
• Fistula
• Cellulitis
• Exuberant Granulation tissue

13. Treatment of wound
• Open wounds can be divided into following
Categories
• Surgical/aseptic wound
• Contaminated wounds
• Accidental traumatic wounds

14. Aseptic wounds
• Management of aseptic wound
• A surgical wound is considered as an aseptic wound although no wound is
totally free from microbes, the slight infection which exists may not retard
healing.
• A prophylaxis against tetanus is advocated, specially in camels, goat etc
• Avoid excessive hemorrhage, trauma to tissues and drying of tissues while
performing surgery, this increases chances of infection.
• Provide proper drainage and avoid dead space and prevent haematoma,
seroma formation.
• Systemic use of specific antibiotics as therapeutic or prophylaxis is usually
recommended along with topical medication to minimize wound infection
• In summer months fly repellents should be considered to avoid maggot
infestation.
• Rest is advocated to prevent mechanical disturbance to wound healing

15. Management of contaminated
wound
• Contaminated wound
• Wound infection is the most important cause of morbidity and mortality in
injured animals
• A fresh wound gets contaminated beyond 4-5 hrs of injury. All measures to
check infection should be taken to avoid pathologic effects.
• This period can be extended to 24 hrs if antibiotics have been instituted
within first 6 hrs of injury.
• The susceptibility of wound to infection increases with ischemia.
• Certain factors predisposing the wound to infection, and must be
eliminated.
• Factors include
• Type of and number of microorganisms
Type and location of the wound
• Blood flow to the wound site
• Presence of foreign material or dead tissue at the wound site.
• Cont….

16. • Copious lavage and thorough debridement are most essential to
manage contaminated or infected wounds.
• After adequate haemostasis the wound and its periphery should be
thoroughly cleaned with warm normal saline or water and soap or
2% hydrogen peroxide, 5% Dettol or 0.5% solution of potassium
permanganate is also effective.
• Clipping and shaving of a large area around the wound
• Wound debridement is done for removal of necrosed and devitalized
tissue either by excising or by use of topical medicaments
• eg for topical medicaments include,2.5% sodium
chloride,magnesium sulphate and glycerine paste,bismuth –
iodoform-paraffin paste,2% hydrogen peroxide,and 0.5% sodium
hypochlorite. Cont….

17. • Infected and deep penetrating wounds are not sutured until infection
is well controlled
• Reconstruction of the various tissue layers and other structures are
done by interrupted sutures.
• When wound edges cannot be brought close open wound healing
by granulation tissue formation is allowed /tissue graft /plastic
surgery is recommended.
• Before wound closure it is important to keep the following points in
mind
• Condition and location of wound
• Adequacy of debridement
• Health of tissues
• Degree of contamination etc cont….

18. • If the aforementioned points are unfavorable, delayed primary
healing of open healing by granulation should be considered.
• Primary wound healing can be delayed upto 5th day of injury.
• Provision for drainage should be considered.
• In any case of doubt of a wound being appropriate for primary
healing it should be kept open and kept soaked with antiseptics or
normal saline , with the dressing to be changed every day.
• Multifilament sutures should not be used in infected wounds
• Monofilament nylon is best suited for the purpose
• Polyglycolic acid sutures are also satisfactory for use
• In case of maggot wounds,the area is irrigated with 1:1 chloroform
and turpentine oil, the wound is curetted to remove the dead larve
• In case of exuberant granulation tissue use of astringents like
copper sulphate are recommended followed by bandage.

19. Accidental Traumatic wounds
• Accidental and traumatic wounds
• The first aim is to check hemorrhage and prevent shock
• Most accidental wounds are contaminated and there is great danger
of development of infection.
• Management should be done on the line of contaminated wound
• Ie cleansing, excision, debridement, and delayed primary closure,
systemic and topical antibiotics.

20. ABSCESS
• Abscess
• An abscess is a painful collection of pus caused by a bacterial
infection.
• Types of abscess
• Skin abscesses – which can develop anywhere on the body
and occur when a bacterial infection causes pus to collect in the skin
• Internal abscesses – which develop inside the body following
an infection or an injury
• Treating an abscess
• Abscesses can be treated in a number of different ways depending
on the type of abscess and how large it is.
• The main treatment options include:
• Antibiotics
• a drainage procedure
• surgery

21. Haematoma
• Haematoma refers to a collection of blood
outside of the blood vessels, which gathers in
body tissues or cavities. Haematoma are most
commonly apparent as bruising to the skin, and
are caused by internal bleeding into the
extracellular space following blunt trauma - this
can include accidents, falls and surgery.
• If the patient takes anti-coagulant therapy, such
as warfarin or aspirin it may develop into large
haematomas

22. • Treatment
• Hematomas of the skin and soft tissues
are often treated with RICE (rest, ice,
compression, elevation)
• Surgical drainage depending of specific
situation eg aural haematoma, cerebral
haematoma.

23. Cysts
• Cyst
• A cyst is a sac containing liquid, a cyst consists of inner lining of secreting
membrane.
• Cysts are non inflammatory and slow in development. They have a well
defined periphery. A cyst containing fluid will fluctuate uniformly.
• Different varieties of cysts
• Retention cyst
• Exudation cyst
• Congenital cyst
• Encapsulation cyst
• Degeneration cyst
• Treatment cont…

24. • The cyst is punctured with inoculation needle and the
contents are evacuated
• A irritant solution like tincture iodine is injected into the
cavity to destroy the secretary lining membrane.
• The cyst may also be incised to evacuate the contents.
• Passing a seton through the cyst
• Excision of the cyst is the best method of treatment
when it is practicable.The cyst is isolated from the
surrounding tissues by dissecting around it and is
removed just like a tumor.
• When the cyst is very large and deep seated it might be
desirable to open the cyst before dissecting it.

25. BURN
• Burn
• A burn is an injury caused by hot solids, flame etc. A scald is an injury
caused by liquids or steam. A scald is likely to be more severe than a burn
because steam can penetrate deeper into the tissues.
• Chemical burn Injuries caused by chemicals like strong acids and alkalis are
referred to as chemical burns.
• Burns are classified into three types depending on the severity
• First degree- involving only the epidermis
• Second degree- In which the whole thickness of skin sparing the
subcutaneous fat.
• Third degree – In which deeper tissues like subcutaneous fat and muscles
are also involved.
• The prognosis depends upon the extent of injury. Prognosis is grave if
more than 50% of skin is involved.
cont..

26. (sheds)

27. 3rd to 4th degree

28. Fourth Degree Burns
• Prone to infection because of the extensive
tissue damage
• Are exposed to environment contamination
• Result in large volumes of electrolytes and
protein loss through the wound surface.
• Compromise the condition of the animal

29. • Treatment
Burn involves loss of tissue and muscle
destruction, associated with loss of
potassium, therefore treatment should
aim at
1. Prevention of dehydration and shock
2. Local application of emollients
3. Local analgesics.
4. Local and systemic antibiotics

30. Necrosis
• Necrosis is a form of cell injury that results in the
premature death of cells in living tissues. It is the sum of
cell changes after localized cellular death through a
process known as autolysis
Examples of necrosis are
• Coagulative necrosis, Liquefactive necrosis, Ischaemic
necrosis, Embolic necrosis.

31. • The standard therapy for necrosis is removal of the dead
tissue (debridement) either by surgical or non-surgical
means.
• Depending on the severity of the necrosis, this may
range from removal of small patches of skin, to complete
amputation of affected limbs or organs.
• Chemical removal of necrotic tissue is another option in
which enzymatic debriding agents, categorised as
proteolytic, fibrinolytic or collangenases, are used to
target the various components of dead tissue.
• In select cases, special maggot therapy using Lucilia
sericata larvae has been employed to remove necrotic
tissue and infection.

32. Gangrene
• Gangrene: Gangrene is a serious and potentially life-threatening
condition that arises when a considerable mass of body tissue dies
(necrosis).
This may occur after an injury or infection, or in patients suffering from any
chronic health problem affecting blood circulation.
The primary cause of gangrene is reduced blood supply to the affected
tissues, which results in cell death
• Gangrene can be classified into
• Dry gangrene: In dry gangrene the dead tissues become dry and reduced in
volume. Dry gangrene is mainly due to arterial occlusion
• Wet Gangrene: It is seen in tissues having high fluid content. It occurs in
naturally moist tissue and organs such as the mouth, bowel, lungs, etc. It is
characterized by numerous bacteria and has a poor prognosis (compared to
dry gangrene) due to septicemia

33. • Treatment
• Treatment is usually surgical debridement,
wound care and antibiotic therapy
although amputation is necessary in many
cases.

34. Fluid therapy in surgical patients
• Disturbances in water, electrolyte and acid –
base balance in the operative period may have
life threatening consequences unless they are
identified and treated appropriately
• An integrated approach should be taken up to
meet the fluid, electrolyte and acid –base
requirements starting from the preoperative
period and carried into the post operative period
to avoid morbidity and mortality.

35. Distribution of normal body water
• Total body water is 60% of the body
weight.It is divided into two functional
compartments
• Extra cellular (20%of total body fluid,
Interstitial 15% and intravascular 5%)
• Intracellular spaces (40% of total body
fluid).

36. • Intercompartmental water balance
• The number of active particles in each space
determines the volume of the intracellular and
the extra cellular fluid compartments
• Osmotically active particles are nondiffusible
particles in solution that exert osmotic pressure.
• Osmotic pressure is determined by the number
of particles in solution not the type of particles
• Osmolarity is the osmomole concentration of a
solution.

37. • Solutions that have same tonicity to
plasma are isotonic.
• those with higher osmolarities are
hypertonic
• those with lower osmolarities are
hypotonic
• Normal plasma osmolarity of plasma is
290 to 300 mOsm/L.

38. • All fluid compartments are isotonic with each other
• Sodium and chloride predominate in the extracellular
fluid space and potassium is present in intracellular fluid
• The volume of the fluid in the intravascular compartment
is determined by the balance between the forces that
favor filtration of fluid through the vascular endothelium
(ie capillary hydrostatic pressure and tissue oncotic
pressure
• the forces that favor retention of fluid within the vascular
space( ie plasma oncotic pressure and tissue hydrostatic
pressure)

39. Fluid and solute loss
• Normal fluid loss can occur as urinary, fecal, and
salivary water losses and respiratory and
cutaneous evaporative losses.Cutaneous losses
are insignificant in dogs and cats
• Third space volume losses refers to reduction of
effective intravascular volume through loss of
fluid into a nonvascular space within the body.
Third space losses can occur in peritonitis,
interstitial hemorrhage and soft tissue trauma.

40. • Fluid loss may be isotonic, hypertonic or
hypotonic .
• Water deprivation is an example of the loss of
hypotonic fluid in which free water loss occurs
without loss of solute. This results into increase
in tonicity of the extracellular fluid as compared
to intracellular fluid resulting in shift of fluid from
intracellular space into the extra cellular space
to establish equality in the two osmolarities.
• If the loss is characterized by loss of solute
without water loss fluid shifts from ECF space
to the ICF space to maintain equal ECF and
ICF osmolarities.

41. Evaluating and monitoring fluid and
electrolyte balance
• An accurate history provides information
about the nature and the extent of the
animal’s fluid and electrolyte status
• Information about the animal’s food intake,
water intake, and urine production and the
time course of the disease process is
obtained
• Physical examination provides information
about the degree of dehydration.

42. • Assessment of skin turgor
• mucous membrane moisture,
• peripheral pulse quality and rate
• capillary refill time
• jugular venous distension
• orbital prominence provide information
about the hydration status.

43. Clinical signs of interstitial
dehydration
Dehydration % Clinical signs
0-5 Not detectable
5-6 Subtle loss of skin turgor
6-8 Definite loss of skin turgor,
Slight prolongation of capillary refilling time
Dry mucous membrane
Eyes possibly sunken in the orbit
8-10 Considerable loss of skin tugor
Prolongation of capillary refilling time
Eyes sunken in orbit
Dry mucous membrane
Weak pulse possible
>10 Complete loss of skin tugor
Marked prolongation of capillary refilling time
Eyes severely sunken in orbit
Extremely dry mucous membrane
Weak, thready pulse
Possible altered level of conciousness

44. • Laboratory parameters assist in evaluation of the animal
• Total plasma protein
• Packed cell volume
• Urine specific gravity
• The packed cell volume and total plasma protein increase with
all types of fluid loss except hemorrhage.
• Evaluation of serum concentration reveals the type of loss
(hypertonic, hypotonic, and isotonic) and assists in selection of
replacement therapy.
• Evaluation of blood urea nitrogen, glucose,and electrolyte
concentrations can yield information because they are used in
calculation of serum osmolarity.
• Central venous pressure is measured to assess hydration,
normal pressure varies between 0-10cm water, a
vasoconstricted, hypovolemic animal may have a central
venous pressure of 5 cm of H2O
• Urine output also provides the information on hydration.
Hypovolemic animals may be oligemic animals may.Normal
urine output is 1 to 2 ml/kg/hr.

45. Fluid therapy plan formulation
• Preoperative fluid therapy
• The preoperative estimation of fluid balance is based on
clinical, laboratory and physiological parameters.Fluid
requirements can be divided into three major
compartments
• Rehydration/Replacement
• Maintenance
• Ongoing losses.
• The amount of fluid required to treat pre existing
dehydration can be calculated
• % dehydration in decimal x bdy wt in kgs = number of
liters deficit. Multiple this by 1000 and it will give ml dose
• Ex. A 4.5KG cat is 8% dehydrated
.08 x 4.5kg = .36L x 1000 = 360ml needed to be
replaced

46. • Estimation of contemporary losses is based on
assessment of volume of ongoing losses due to
vomiting, diarrhea, burns, open wounds, fever,
and continued third space losses.
• The rate of administration of fluid to correct an
existing deficit and significant ongoing loss is
determined by the severity of clinical signs, the
time course of loss, the magnitude of
contemporary loss
• Animals with clinical signs consistent with mild to
moderate hypovolemic shock may be given
fluids at 50 to 90 mL/kg/hr.

47. • The calculated deficit can be added to the
calculated maintenance requirements and
administered during 24 hr period.
• Animals with fluid deficits that must
undergo anesthesia and surgery may have
the deficit replaced during 4-8 hrs
• In most dogs and cats, 40-60 mL/Kg/day
provides sufficient maintenance fluid.

49. Fluid therapy during surgical period
• In addition to correction of existing fluid deficits
preoperatively and meeting normal fluid requirements
special consideration should be given to monitor ongoing
loss during surgery and anesthesia
• Animal undergoing surgery require volume replacement
beyond simple blood loss that improves intravascular
fluid volume and assist in making hemodynamic stable
profile.
• Intravenous and inhalation anesthetic agents have
variable but mostly negative effects on the myocardium,
venous return, baroreceptor responses,blood pressure
etc.
• Anesthetics may also blunt the normal physiological
response to stress and hypovolemia

50. • Surgery may also cause blood loss. Fluid
requirements during the operative period
depends on length and complexity of surgery.
• In patients which do not require special
consideration of fluid type or composition, the
rule for replacement during the anesthetic period
may be successfully carried out with an isotonic
crystalloid solution administered at a rate of 10
mL/kg/hr.

51. Post operative period
• Fluid administration in the immediate post
operative period depends on the individual
needs of the animal
• Deficiencies incurred during surgery that
have not been replaced are met
• As the effects of anesthesia and surgery
ware off and the animal returns to normal
hemodynamic status, fluid administration
is readjusted to continue maintenance.

52. Fluid selection
• Fluid types
• Fluid types are categorized according to their tonicity, composition
relative to extracellular fluid, molecular weight and distribution of
components.
• S olution that have the same tonicity plasma as are isotonic,
those with higher osmolarities are hypertonic and those lower are
hypotonic
• Solutions that have a composition similar to plasma are called
balanced and those that do not are unbalanced
• Crystalloids solutions contain electrolytes and other solutes that can
distribute themselves throughout all of the fluid compartments.
• Colloids solutions contain substances that are restricted to the
intravascular fluid compartment by virtue of their large molecular
weights.

53. • Crystalloids can further be subdivided into maintenance
and replacement solutions.
• Replacement solutions
• Replacement solutions are isotonic and are either
alkalizing or acidifying.
• Alkalizing solutions contain some form of bicarbonate
precursors, lactate, acetate or gluconate
• Lactate is metabolized by either gluconeogenesis or
oxidation. The majority of this metabolism occurs in the
liver. Acetate is metabolized in the muscles and
gluconate in most cells in the body.

54. • Acidifying solutions
• Both normal saline and Ringers solution are
acidifying.
• They are replacement solutions that are
unbalanced, largely because of their high
concentration of chloride compared with plasma.
• This high concentration of chloride compared
promotes the development of hyperchloremic
metabolic acidosis.

55. Indications for use
• Alkalizing replacement solutions are used in animals with
fluid loss due to gastrointestinal disease, renal disease,
shock and metabolic diseases for which the
administration of bicarbonate precursor is beneficial
• Replacement solutions are also the primary choice of
fluid for surgical maintenance. Normal rates of
administration for surgical maintenance are 5 to 10
mL/kg/hr.
• Hypotension associated with the effects of anesthesia
alone, as opposed to hypotension due to significant
blood loss during the operative period, may respond to
the compensatory intravascular volume expansion
provided by administration of a bolus (10 to 20 mL/kg)
administered during a 15-20 minute period.

56. • Calcium containing solutions are not
administered through the same intravenous line
because blood products may clot.
• The administration of large quantities of acetate
containing solutions can produce vasodilation
sufficient to induce an increase in heart rate but
not a reduction in blood pressure, therefore
administration of large volumes of acetate
containing solutions are contraindicated in
animals with hypovolumia

57. • Acidifying solutions as replacement fluid are
(Normal saline, ringers lactate) are indicated in
the treatment of animals with metabolic
alkalosis, hypercalcemia, hyponatremia, and
hyperkalemia
• Dextrose containing solutions
• Five percent dextrose in water is an isotonic
solution that is used as a source of free water.
The dextrose is rapidly metabolized on
administration, leaving only free water. Dextrose
is not used as primary replacement solution
during surgery and anesthesia.

58. Maintenance
• Commercially prepared maintenance solutions that are
designed to meet the electrolyte requirements of animals
with normal electrolyte losses contain less sodium
(40to60 mEq/L) and more potassium (15 to 30 mEq/L)
than replacement solutions do
• Maintenance solutions are used when hypernatremia
may develop after the prolonged administration of
crystalloid solutions with high sodium concentrations.
• Although the potassium concentration of commercially
prepared maintenance solutions is higher than
replacement solutions its content may be inadequate.
Further supplementation of the solution is indicated due
to potassium losses associated with vomiting,diarrhea,
diuresis or polyuria.
• Care should be taken that the potassium administration
rate should not exceed 0.5mEq/kg./hr.

59. Administration of whole blood ,
blood extracts and plasma
substitutes
T

60. • Transfusion of whole blood, blood extracts and plasma
substitutes are commonly used for replacement and supportive
therapy.
• The solutions are colloidal in nature, contain molecules that do
not pass through capillary walls and remain within the
intravascular space where they exert an osmotic pressure.
• When large quantities of blood or plasma are lost , it is
preferable to utilize both colloids and crystalloid solutions in a
ratio of 1:3 or 1:4
In case of rapid exsanguinating blood loss, only colloid
solutions will rapidly increase intravascular volume and
maintain an adequate blood pressure until the haemorrhage
can be controlled. Under these conditions compatible whole
blood is the ideal replacement

61. Use of whole blood
• Although the best replacement or substitution for
lost blood,citrated blood is not a completely
physiological replacement due to low
temperature (4-6 C), Low pH ( 6.6-6.8)and
excess of lactate, pyruvate and citrate and a
deficiency of calcium platelets and clotting
factors V and VIII.
• Whole blood is used primarily as replacement of
blood lost during surgery and in the treatment of
haemorrhagic shock.

62. Other indications of blood transfusion are
Thrombocytopenia
Hemophilia
Prior to surgery in debilitated or toxic animals
Anemia associated with hook worm infection.

63. Canine blood types
• Seven agglutinogens ( antigens or factors) are known
to occur in dogs and they are designated
A,B,C,D,E,Fand G
• A-antigen is the sole antigen capable of producing
major reactions following transfusion and the only one
of importance.
• In canine A system there are 2 distinct A antigens
• A) Cells that are hemolyzed in the presence of fresh
anti-A serum are designated A1
• B) Cells that are not hemolyzed but agglutinated are
called A2

64. • About 60% of dogs selected at random have
erythrocytes with the canine A factor ie A positive and
the remaining 40% are A negative
• One in 4 transfusions from random donors will result in
the stimulation of anti A antibodies in the recipient
• If the dog has a second transfusion and the donor is
again chosen at random there is `5% chance that the
recipient has been sensitized by the first transfusion
and receiving incompatible blood.
• Within 10 days of a single transfusion of A1 cells into a
A-negative recipient , anti-A antibodies appear in the
circulation and cause accelerated breakdown of the
transfused A1 cells.

65. • If A1 positive blood is given to a previously sensitized
A- negative recepient , as in a a second transfusion , a
hemolytic reaction will be apparent.
 When haemolysis is rapid the animal will have tremors
 Emesis
 Incontinence of urine and feces
 Becomes febrile and prostrate within a few minutes
 Fall in cardiac output and hypotension
 Hives and dyspnea transient paresis of the hind limbs
and convulsions.
 Haemoglobinemia and hemoglobinuria.

66. • Only healthy fasted animals should be used as donors
After administration of ultrashort acting anesthetic,
blood maybe collected from the jugular vein or by
cardiac puncture. Most healthy donors can give 10-
20ml/kg every 2 weeks.
The amount of blood to be given varies according to
the reason for transfusion. For less acute conditions
doses of 10-15ml/kg are reasonable, at a rate of 5ml
per minute.