Pre-Surgical
Coagulation
Testing. Why
Your Practice Can’t
Live Without It.
Contributing Author:
Andrew J. Rosenfeld, DVM, DABVP
Case Study
Read this case study submitted
by Andrew Rosenfeld, DVM,
DABVP.
Cocoa Marshmallow, a 1 year
old female Boxer Mixed Breed
dog presented for a routine
ovariohysterectomy.
The following are a series of standard
pre-anesthetic questions that were asked
to Cocoa’s owner.
2011
2011 Sept/Oct
9
Pr e - S u r g i c a l Co a g u l at ion Testing
Questions to ask.
Q. When did Cocoa last eat?
A. Last night’s dinner at 6 pm.
Q.Any recent coughing, sneezing, diarrhea,
vomiting, excessive urination or excessive
drinking?
A. None
Q.Any history of anesthetic issues or
concerns?
A. None
Q. Any history of previous disease?
A. None
Q. Are vaccines up to date?
A. Yes
Table 1: Pre-surgical CBC
Test
Result
Normal
WBC
10,250
5,500-19,500
Lymphocytes
1725
1500-7000
Monocytes
500
0-850
Neutrophils
7025
2500-12500
Eosinophils
1000
0-1500
Basophils
0
0-100
RBC
6000
5500-8500
Hemoglobin
11
9.5-15
Platelet
245,000
200000-500000
Table 2: Pre-surgical Chemistry Panel
Test
Result
Normal
Albumin
3.4
2.5-4.4 g /dl
Alk Phos
65
20-150 IU/L
ALT
70
10-118 IU/L
Amylase
1200
200-1200 IU/L
T Bilirubin
0.2
0.1-0.6 mg/dl
BUN
14
7-25 mg/dl
Calcium
9.2
8.6-11.8 mg/dl
No abnormalities were noted on Cocoa’s
physical and her pertinent clinical data was
as follows:
Phosphorus
4.6
2.9-6.6 mg/dl
Creatinine
0.8
0.3-1.4 mg/dl
Glucose
108
60-110 mg/dl
• Temp: 100.3°F
Na
139
138-160 mEq/l
• Pulse: 125 bpm
K
3.9
3.7-5.8 mEq/l
TP
6.6
5.4-8.2 g/dl
• Resp: 20-30 breaths/min
Globulin
3.2
2.3-5.2 g/dl
• CRT: <2 secs
• MM: Pink
• Hydration: WNL
Q. Are other pets in the house OK?
A. There are no other pets in the house.
Q. Is Cocoa currently on an over-the-counter,
prescription or homeopathic medication?
A. Heartworm prevention
Cocoa’s pre-surgical CBC was performed on
the Abaxis Vetscan HM5 and the chemistry
panel was performed on the Abaxis Vetscan
VS2. No abnormalities were noted (Tables 1,
2). Urinalysis results were unremarkable (Table
3) and her pre-surgical systolic blood pressure
was 105 mmHg.
10 Sept/Oct 2011
Table 3: Pre-surgical Urinalysis
Test
Result
Normal
Urine specific
gravity
1.044
>1.035
Protein
Neg
Neg
Blood
Neg
Neg
Glucose
Neg
Neg
pH
6.5
7.0
Sediment
No significant
findings
P re -Surg ical Coag u l at io n T e s t in g
Cocoa was pre-medicated with 0.1 mg
glycopyrollate and 0.05 mg acepromazine.
She was induced with 50 mg ketamine and
2.5 mg Valium IV and maintained on isoflurane
during the procedure. The procedure was
routine except that mild to moderate bleeding
was noted throughout the procedure. Postoperatively, she was given 2.2 mg/kg Carprofen
IM for pain management.
During recovery, it was noted that the incision
continued to ooze blood and there was
light bruising around the surgical site. Post
operative physical examination and TPR were
unremarkable and her systolic blood pressure
was 125 mmHg. Because of the continued
bleeding and bruising, additional postoperative blood work was performed. This
included acid-base status evaluation using a
Vetscan i-STAT 1 analyzer and a coagulation
profile utilizing a Vetscan VSpro Coagulation
specialty analyzer (Table 4).
Table 4: Post-operative Blood Values
Test
Value
Normal
PCV
25 (L)
25-55%
TP
5.2 mg/dl
5-7.5 mg/dl
ALB
1.8 mg/dl (L)
2.5-3.5 mg/dl
PT
22 (H)
12-17 sec
aPTT
95
90-110 sec
GLU
115
60-115
BUN
15
10-26
Na
143
142-150
K
3.8
3.4-4.9
Cl
125
106-127
tCO2
19
17-25
Anion Gap
8
8-25
Hct
23 (L)
35-50
HgB
8 (L)
12-17
pH
7.37
7.35-7.45
PCO2
35
34-40
HCO3
22
20-40
Base Excess
-1
-5-0
Why pre-surgical coagulation
testing is necessary.
Results of these tests indicated
that bleeding was actively
occurring in this patient and
this was likely due to a problem
with the extrinsic side of the
coagulation cascade (factor
VII). Because factor VII is highly
sensitive to the effects of
coumadin type compounds, the
owner was again queried. Upon
more direct questioning the owner
now reported that Cocoa had
ingested rodenticide two days
before the procedure. However,
because she was acting fine, the
owner wasn’t concerned and
forgot to mention it.
Cocoa was transferred to an emergency
care facility to be monitored overnight.
She received 2 units of plasma and was
released the following day on vitamin K
supplementation. Her owner’s cost after the
ovariohysterectomy was more than $2,100.
Coagulation testing is an important part of
the overall pre-surgical testing protocol in
a growing number of veterinary facilities.
Genetic hemophilia, potential exposure to
unknown medications and toxins as well
as, elective and high risk surgical patients,
evaluation of bleeding patients and snake
bite victims are excellent candidates for
coagulation testing. There are many breeds
with known genetic or familial hemophilia
and regardless of their purported incidence,
factor deficiencies of any cause are an issue
when they occur on your patient.
2011 Sept/Oct
11
Pr e - S u r g i c a l Co a g ul at ion Testing
Coagulation testing is readily accepted
by clients. Offering a test that reduces
the chance of surgical complication
is easy to justify and a negative
test result is good news.
Cost is obviously important to the client
as well, and the test must be offered at a
reasonable price to increase compliance. Many
practices offer the pre-surgical coagulation
profile at a price of $30-$40, while the price
on the test for the patients presenting for a
bleeding disorder is higher. This tiered pricing
system is used in many areas of the hospital,
such as different prices for critical exams
versus wellness exams, or for initial radiographic series versus recheck films. The
procedure is the same, but the purpose and
time spent on interpretation is different;
moreover, the perceived value to your client
is also different.
Common Breeds Affected by Genetic or Familial Coagulation Disorders
Factor VII2
Factor VIII2
(Hemophilia A)
Factor IX2
(Hemophilia B)
Factor X2
Factor XI2
(Hemophilia C)
Factor XII2
Beagle1
German
Shepherd1
Many Dogs1
Boxer1
Kerry Blue
Terrier1
Dogs
(Especially
Poodles)1
Alaskan
Malamute1
Mixed Breed
Dogs1
British
Shorthair1
Cocker
Spaniel1
German
Shepherd1
Cats1
Mixed Breed
Cats1
Siamese1
Jack Russell
Terrier1
DSH1
DSH1
1
2
BSAVA Manual of Canine and Feline Clinical Pathology, Second Edition: Villers and Blackwood
Veterinary Hematology and Clinical Chemistry: Thrall
12 Sept/Oct 2011