Blood loss and anemia Flashcards
When does blood loss occur
The most recognized cause of blood loss is traumatic injury which results in shearing of blood vessels. However, there are many causes of blood loss that owners are unaware of
Inability to clot due to inherited lack/malfunction of platelets, fibrin, clotting factors
Toxins that affect clotting
Certain cancers can damage blood vessels
Iatrogenic loss as a result of surgery or blood collection
Immediate response to blood loss
Identify origin of bleeding
Be mindful that you will not see internal bleeding
Apply pressure to where bleeding is originating from
Asses degree of blood loss (conscious, lethargic, pale mm, arrhythmia, weak pulse ← these are signs you need to act fast)
If there is lots of bleeding, place an IV catheter immediately before vessels collapse
Clinical signs of blood loss
External blood
Feces with frank blood (hematochezia) or digested blood (melenia)
Vomit with frank blood or “coffee grounds” (hematemesis)
Internal blood loss
Swelling of the abdomen or SQ space
Problems breathing (if pleural or pulmonary bleeding)
Decreasing blood pressure or pulse strength
Pale mucous membranes
Heart murmur
Epitaxis
Nose bleed
Melena
Digested blood in stool
Usually from the small intestine
Hemoptysis
Throwing up blood
Hematuria
Blood in urine
Hematochezia
Frank blood in stool
Origin is typically the large bowel
Anemia
Decrease int he number of RBCs
Ischemia
Lack of blood flow to tissues
Common causes of anemia
Bone marrow pathology
Iron deficiency
Chronic renal failure
Oxidative injury to RBCs
Infectious anaemia due to parasites or viruses
External and internal blood loss
Immune-mediated
What is the function of RBCs
Carry O2 to tissue
Lack of O2→ hypoxia
Remove CO2 from tissues
Build up of CO2→ acidosis
Clinical signs of anemai
Pale to white mm
Icterus may be noted if RBCs are being destroyed within the blood vessels
Tachycardia
May be tachypneic
Lethargy, weakness, exercise intolerance
Diagnostic test for anemai
Decreased RBCs
Measured as drop in hematocrit (Hct), packed cell volume (PVC)
Signs of blood loss seen on diagnostic tests
Decreased RBC
AND decreased platelets, decreased WBCs, decreased serum proteins
Treating acute anemia
Acute loss
All of a sudden
Tissue cant adjust
Transfusion if <21%
Treating chronic anemia
Chronic loss
Over time
Tissue adapt
Transfusion if PCV <16%
Overall better prognosis
Response/treatment to blood loss
Asses for blood loss/anemia
Stop any visible blood loss
Assess degree of blood loss
IV fluids to support BP
Blood transfusion if necessary
When to do a blood transfusion
Mild-moderate risk if carried out correctly, potentially lethal if not done correctly
Blood loss
Dramatically improves patients diagnosis
Normal PCV of most species is between 35-50%
Blood types are determined by
Determined by proteins on the surface of the animals RBCs
-Blood group antigens
Some antigens stimulate more of an immune response than others
-These are more likely to cause transfusion reactions
Alloantibodies care and how to use them for your advantage
Antibodies that an individual is born with that recognize foreign blood group antigens
Cats
Species that don’t have alloantibodies need to be exposed to a blood group antigen to produce antibodies against it
Does alloantibodies affect how we do blood transfusions and how
YES!!
Cats- blood type of recipient and donor MUST be determined before a transfusion ALL OF THE TIME
Dogs- can have up to one “free transfusion” in the event of an emergency
Blood typing
identifying an animals blood group antigens
Matching
ensuring that the recipient and the donor are compatible to one another
Major cross-match
ensure that the host will not reject the donors blood
Minor cross match
ensures the donors serum does not contain alloantibodies that will damage the hosts RBCs
