1. Practical Hematology Blood Loss Anemia
Wendy Blount, DVM

2. Practical Hematology Anemia 101 Blood Loss Anemia Hemolysis
Non-Regenerative Anemias
Transfusion Medicine
Polycythemia
Bone Marrow Disease
Coagulopathy
Central IV Lines
Leukophilia
Leukopenias
Splenic Disease

3. Nubbin Wayne 6 year old neutered male Boston Terrier
CC: lethargy, very attentive owners, UTD
Exam – pale pink mm, feces normal on rectal
CBC – PCV 21%, Hb 7 g/dl, RDW 20%
Panel/lytes – alb glob 1.3 = TP 3.5 g/dl
Ca 8.5 mg/dl 3.5 – 2.2 = 1.3
UA – NSAF (with sediment)
Fecal flot and direct – neg
Fecal cytology – RBC & proportional WBC (peripheral blood)
+ 8.5 = 9.8 (normal)

4. Nubbin Wayne Problem – anemia, PLE CBC – PCV 21%, Hb 7 g/dl, RDW 20%
Panel/lytes – alb 2.2 g/dl, Glob 1.3 g/dl
Fecal cytology – peripheral blood
DDx:
Anemia – suspect regenerative
GI Blood loss most likely
Less likely chronic hemolysis and separate panhypoproteinemia
Possible non-regen. anemia from IDA
Unlikely bone marrow disease with separate panhypoproteinemia
- GI Blood Loss

5. Nubbin Wayne Tier 2 tests: Reticulocyte count
Check for autoagglutination
DDx EDTA tube agglutination:
rouleaux
autoagglutination

6. Nubbin Wayne Tier 2 tests: Reticulocyte count
Check for autoagglutination
DDx EDTA tube agglutination:
rouleaux
autoagglutination
Check for gross aggregation
1 drop saline + 1 drop blood on a slide
Tip on a white background

7. Nubbin Wayne Tier 2 tests: Reticulocyte count
Check for autoagglutination
DDx EDTA tube agglutination:
rouleaux
autoagglutination
Check for gross aggregation
1 drop saline + 1 drop blood on a slide
Tip on a white background

8. Nubbin Wayne Tier 2 tests: Reticulocyte count
Check for autoagglutination
DDx EDTA gross slide aggregation:
rouleaux
autoagglutination
Check for micro autoagglutination
5+ drops saline + 1 drop blood on a slide, add cover slip
Dilute until RBC are not touching

9. Nubbin Wayne Nubbin Wayne Tier 2 tests: Reticulocyte count
Check for autoagglutination
DDx EDTA gross slide agglutination:
rouleaux
autoagglutination
Check for micro autoagglutination
5+ drops saline + 1 drop blood on a slide, add cover slip
Dilute until RBC are not touching
Nubbin Wayne

10. Nubbin Wayne Tier 2 tests: Tx: Reticulocyte count - pending
Check for autoagglutination - negative
PT, PTT sent to local hospital – both high off scale
History? No known exposure to rodenticides
Tx:
Vitamin K3 2.5 mg/kg PO x 21d
Fenbendazole 50 mg/kg PO SID x 3d, repeat in 2 weeks
Famotidine 10 mg PO SID
Sucralfate 0.5 g PO BID – 1 hr after other meds and on empty stomach

11. Nubbin Wayne Recheck 4 weeks later – lethargic again:
Reticulocyte count – 440,000/mcL
PCV 18%
PT, PTT sent to nearby vet clinic – both normal

12. Nubbin Wayne Recheck 4 weeks later – lethargic again:
Reticulocyte count – 440,000/mcL
PCV 18%
PT, PTT sent to nearby vet clinic – both normal
History? No black tarry stools - normal
Fecal cytology – peripheral blood
DDx blood loss anemia:
GI blood loss
(third space blood loss, hemolysis)
Plan: recheck for autoagglutination - neg
Thoracic and abdominal rads – NSAF
Abdominal ultrasound – NSAF
Refer for endoscopy

13. Nubbin Wayne endoscopy: Bleeding ulcerative lesion in the ileum
Endoscopic biopsies – GIST, low grade
Clean borders on anastamosis and resection
Dx – leiomyosarcoma
Long term follow-up
No recurrence of neoplasia
Developed hyperadrenocorticism 6 years later
Euthanized at the age of 14 for multiple problems unrelated to neoplasia

14. Nubbin Wayne Lessons from Nubbin Wayne:
Avoid using human labs for animal coags – calibration makes results unreliable
Significant GI blood loss can be present without melena
Fecal cytology & endoscopy can help find it
Always confirm gross hemagglutination with microscopic saline dilution >> 1:1
Pattern - Low PCV plus low alb & glob
look for GI blood loss
GI neoplasias can be present and bleed, but not show up on x-rays or ultrasound
Erosive carcinomas are the most likely offenders (Schirrhous ACA, SCC)

15. DDx Blood Loss Anemia Q1 - Localized or General? Localized bleeding
External usually obvious – trauma, surgery, bleeding pathology from neoplasia or infiltrative disease
Internal – pericardial-thoracic causes dyspnea before anemia, abdominal-retroperitoneal may be more subtle
GI, urinary, (respiratory) – owner may not notice
Generalized bleeding - Coagulopathy
Petechiae, ecchymoses, cavity bleeding if severe
Generalized bleeding may be most apparent at one location (coughing or urinating blood)
Coags always indicated for blood loss anemia

16. DDx Blood Loss Anemia Q2 – Acute or Chronic? Acute Blood Loss
Takes about a weeks to show regeneration
Chronic Blood Loss
Starts out highly regenerative
Can become non-regenerative from IDA if blood loss is external

17. Acute Blood Loss Q3 – How much blood has been lost? Total blood volume
8-10% of body weight in dogs
6-8% of body weight in cats
<20% blood loss is well tolerated
<8-10 ml/lb in dogs
<6-8 ml/lb in cats
30-40% blood loss
Hypotension and shock
Weak pulses, cold extremities
Laterally recumbent
50% blood loss
Can be fatal if over less than 2-3 hours

18. Acute Blood Loss Response to Acute Blood Loss Within a few hours
EPO levels rise
Platelets drop no lower than 60,000/ul
Stress leukogram is possible
Within 2-3 days
Bone marrow response begins
Restoration of plasma volume
Following PCV can grossly underestimate acute blood loss
Recovery within a week of hemostasis
May have rebound thrombocytosis

19. Treating Acute Blood Loss
Stop the Bleeding
Replace fluid loss
Oxygen support
Treat underlying disorder

20. Treating Acute Blood Loss
Stop the Bleeding
Assess coagulation status
External arterial bleeder
Temporary
Cautery - silver nitrate, Kwik Stop, electrocautery
Epinephrine
Permanent
Excise abnormal tissue for biopsy
Reveal normal artery and ligate

21. Treating Acute Blood Loss
Stop the Bleeding
Abdominal bleeder
diagnostic surgery as soon as vascular volume and oxygen carrying capacity restored
GI bleeder
Fecal occult blood testing???
Sucralfate PO – 1-3g in a slurry
Barium PO – 3-5 ml/lb

22. Treating Acute Blood Loss
Stop the Bleeding
Abdominal bleeder
diagnostic surgery as soon as vascular volume and oxygen carrying capacity restored
GI bleeder
Fecal occult blood testing??
Sucralfate PO – 1-3g in a slurry
Barium PO – 3-5 ml/lb
Endoscopic cautery
surgery

23. Treating Acute Blood Loss
Replace fluid loss
crystalloids
10 ml/lb bolus and then reassess
1-2 ml/lb/hr when hypovolemia replaced
Colloids
Hetastarch
5 ml/lb over 5-15 minutes
repeat once if needed
Oxyglobin
3-5 ml/kg added to fluids running at 0.5-2ml/lb/hr (CRI)
Or 10 ml/kg/hr for up to 3 hours (bolus)
If IV access is difficult, try intraosseous

24. Treating Acute Blood Loss
Oxygen support
Transfusion – RBC or whole blood
Oxyglobin
Oxygen – nasal, flow-by, mask, intubate
Treat underlying disorder

25. External Blood Loss
HALLMARK OF EXTERNAL BLOOD LOSS (triad) after 2-3 days
Anemia
Hypoproteinemia – albumin and globulin
Reticulocytosis
If also melena, hematochezia or RBC on fecal cytology – suspect GI blood loss
Check urine for blood loss there (avoid cystocentesis until coagulopathy ruled out)
Respiratory bleeding can be swallowed, and show as hematemesis and/or fecal blood

26. Savita Wadhwani Austin TX

27. Treating Acute Blood Loss
Transfusion
PCV threshold higher for acute blood loss
20-25% with signs of hypoxia
Or if going to surgery
Improves oxygen carrying capacity
May improve hemostasis
Normally, transfusion of 10 ml/lb whole blood is given over a minimum of 2 hours
Pretreat with Benadryl® & dexamethasone
Give as fast as is tolerated
Collect blood from the abdomen, pass through filter and re-administer (use anticoagulant)
No limitation on administration rate

28. Treating Acute Blood Loss
HemoNate filter JorVet J0522H
HemoTap Spike JorVet J0522T

29. Chronic Blood Loss
CHRONIC EXTERNAL BLOOD LOSS IS THE MOST COMMON CAUSE OF IRON DEFICIENCY ANEMIA IN DOGS AND CATS
Also CRF (chronic renal failure)
Increased gastrin causes GI ulceration
Chronic blood loss is usually markedly regenerative
Polychromasia less pronounced
Only becomes non-regenerative if very chronic
With time, iron stores in tissues are depleted
liver, spleen and marrow
ferritin - soluble iron stores
hemosiderin - insoluble iron stores

30. Chronic Blood Loss Low Hb, low HCT, low MCHC (hypochromasia)

31. Chronic Blood Loss Low Hb, low HCT, low MCHC (hypochromasia)
Microcytosis (low MCV) – small RBC
leptocytes, dacryoctyes, schistocytes
RBC become stiffer & more susceptible to lysis
Increased nRBC
Thrombocytosis
May exceed 1,000,000/ul
Mechanism unknown
Platelets >1 million warrants search for blood loss, if pet is anemic and not splenectomized
Low globulins and albumin
Suspect if highly regenerative anemia with no IMHA markers

32. Chronic Blood Loss Causes of chronic blood loss and IDA
GI hemorrhage – MOST COMMON
Including inflammatory bowel disease
Both iron malabsorption and bleeding
Ulcer, aneurysm, neoplasia
Kidney disease – ulcers and lack of EPO
Liver disease – ulcers and coagulopathy
Parasitism – GI or otherwise
Fleas
hookworms
Rarely whipworms
Chronic externally bleeding neoplasia

33. Chronic Blood Loss Clinical Signs
Onset insidious - develops over weeks
Seem quite well for severe anemia (<15-20%)
Sudden death can occur
Most common presenting signs
Pallor, exercise intolerance – syncope
pica – eating dirt, rocks, etc.
Intermittent abdominal pain, poor appetite, increased thirst relieves gastric pain
+ vomiting or hematemesis
Melena is not always obvious when there is significant chronic GI bleeding
Bleeding can be intermittent
Fecal cytology to look for RBC can help

34. Chronic Blood Loss Clinical Signs Decreased blood viscosity
Bounding pulses
Physiologic murmur
Gallop rhythm
Increased blood volume
Cardiac eccentric hypertrophy (dilation)
congestive heart failure
Depletion of iron from body tissues
Muscle weakness
Abnormal behavior
Dry brittle Skin and nails, hair loss, abnormally shaped nails

35. Treating Chronic Blood Loss
Correct Anemia - Transfusion
Treat underlying disorder
Correct Iron Deficiency

36. Treating Chronic Blood Loss
Correct Anemia - Transfusion
Anemia severe enough to cause clinical signs (PCV <15-20%)
Or preparing for corrective surgery
Conservative transfusion volume & rate to avoid precipitating CHF
Volume overload more of a problem in cats than in dogs
Use packed cells
Correction of anemia results in resolution of cardiomegaly within several weeks

37. Treating Chronic Blood Loss
Treat Underlying Disorder – GI ulceration
Antacids
Omeprazole 1 mg/kg PO BID for severe ulcers
30 minutes before feeding, at least 2 weeks
Taper to prevent acid rebound
Famotidine 1 mg/kg PO BID x 7 days
Protectants
Sucralfate ½-1g PO TID x 7-10d
NPO 1 hr before or 2 hours after
Barium 3-5 mg/lb once
Butorphanol or Buprenorphine for pain

38. Treating Chronic Blood Loss
Treat Underlying Disorder - others
Deworm/deflea
Treat cause of GI blood loss – endoscopy, surgery, Tx coagulopathy
Confirm blood loss has resolved by monitoring reticulocyte count, after PCV returns to normal
< 40,0000/ul
Retics more sensitive than PCV for monitoring chronic blood loss

39. Summary
Powerpoints - .pptx, .pdf 1 slide per page, .pdf 6 slides per page
Laboratory Information
KSU – Comparative Hematology Submission Form (iron panel)
Vet Handout
Blount – Fluid Analysis Diagnostic Chart

40. Acknowledgements
Chapter 2: The Complete Blood Count, Bone Marrow Examination, and Blood Banking
Douglass Weiss and Harold Tvedten
Small Animal Clinical Diagnosis by Laboratory Methods, eds Michael D Willard and Harold Tvedten, 5th Ed 2012
Chapter 3: Erythrocyte Disorders

41. Acknowledgements Chapter 59: Pallor Wallace B Morrison
Textbook of Veterinary Internal Medicine, eds Stephen J Ettinger and Edward C Feldman, 6th Ed 2003
Challenging Anemia Cases
Crystal Hoh, ACVIM
Heart of Texas Veterinary Specialty Center
CAVMA CE