Transcript Blood Volume Analysis in Clinical Practice

Blood Volume Analysis
in Clinical Practice
Chris Hirt
Daxor Corporation
Account Manager
[email protected]
410-499-7840
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Ways to assess volume status
Clinical indicators (indirect):
•Vital signs: BP, HR
•Input/Output, weights
•Jugular venous distension
•Lung sounds
•Central Venous pressure
•Edema present/absent
•Hematocrit/Hemoglobin
•Pulmonary Artery Catheterization
Direct Measurement:
•Analysis with Daxor BVA-100
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How does BVA work?

Indicator Dilution Technique
 131I
labeled albumin (15 microcuries)
1.0 ml dosimetric syringe
 Very small radiation dose

1.
Inject known
amount /volume
of tracer
2.
Wait for
equilibrium
3.
Measure tracer
concentration,
calculate volume
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Report Example - Hypovolemia
Bench
Work
performed
by Nuclear
Medicine
Patient
Results
BVA
Normal
and
Abnormal
Ranges
BLOOD VOLUME ANALYSIS - FINAL REPORT
Patient Name:
Identification Number: 096784758
Height: 61.5 Inches Weight: 126.5 Pounds (Dev. from Ideal: 9.3%)
Comments: V32406-86
Gender: Female
Analyzed on: 07/14/2003 at 17:42:54 by: Dr.L & JR
Sample Time
Hct-A
Hct-B
Avg
Count-A
Count-B
AvgCnt
UnadjVol
------------------------------------------------------------------------------Control
37.5
37.7
37.6
78
72
75
Standard-1
12081
12603
12342
Pat-Samp-1 12.0
36.6
36.6
36.6
5953
6220
6086
3043
Pat-Samp-2 18.0
36.5
36.7
36.6
6137
5920
6029
3073
Pat-Samp-3 24.0
36.6
36.1
36.3
6018
5880
5949
3104
Pat-Samp-4 30.0
36.5
36.4
36.5
5863
5729
5796
3191
Pat-Samp-5 36.0
36.2
36.5
36.4
5701
5563
5632
3281
------------------------------------------------------------------------------Room Background: 80 counts. Sample Acquisition Time was 3.00 min.
Anti-Coagulation Factor: 1.00 Isotope: I-131 Dose: 9.5 microCi
+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
Blood Vol.: 2910 ml
Ideal Vol.: 3721 ml
Deficit: 811 ml
Devtn.: -21.8 %
Red Cell Vol.: 956 ml
Ideal Vol.: 1341 ml
Deficit: 385 ml
Devtn.: -28.7 %
Plasma Vol.: 1953 ml
Ideal Vol.: 2380 ml
Deficit: 426 ml
Devtn.: -17.9 %
Patient Blood Volume is: HYPOVOLEMIC
Normalized HCT is: 28.5%
Slope is: 0.00314
Standard Deviation is: 33.7 ml ( 1.159% )
------------------------------------------------------------------------------Normal
Mild
Moderate
BV, PV Deviation (+/- %):
0 to 8
>8 to 16
>16 to 24
RCV Deviation (%)
0 to 10
>10 to 20 >20 to 30
Severe
>24 to 32
>30 to 40
Extreme
>32
>40
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Report Example - Hypovolemia
Bench
Work
performed
by Nuclear
Medicine
Patient
Results
BVA
Normal
and
Abnormal
Ranges
BLOOD VOLUME ANALYSIS - FINAL REPORT
Patient Name:
Identification Number: 096784758
Height: 61.5 Inches Weight: 126.5 Pounds (Dev. from Ideal: 9.3%)
Comments: V32406-86
Gender: Female
Analyzed on: 07/14/2003 at 17:42:54 by: Dr.L & JR
Sample Time
Hct-A
Hct-B
Avg
Count-A
Count-B
AvgCnt
UnadjVol
------------------------------------------------------------------------------Control
37.5
37.7
37.6
78
72
75
Standard-1
12081
12603
12342
Pat-Samp-1 12.0
36.6
36.6
36.6
5953
6220
6086
3043
Pat-Samp-2 18.0
36.5
36.7
36.6
6137
5920
6029
3073
Pat-Samp-3 24.0
36.6
36.1
36.3
6018
5880
5949
3104
Pat-Samp-4 30.0
36.5
36.4
36.5
5863
5729
5796
3191
Pat-Samp-5 36.0
36.2
36.5
36.4
5701
5563
5632
3281
------------------------------------------------------------------------------Room Background: 80 counts. Sample Acquisition Time was 3.00 min.
Anti-Coagulation Factor: 1.00 Isotope: I-131 Dose: 9.5 microCi
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
Blood Vol.: 2910 ml
Ideal Vol.: 3721 ml
Deficit: 811 ml
Devtn.: -21.8 %
Red Cell Vol.: 956 ml
Ideal Vol.: 1341 ml
Deficit: 385 ml
Devtn.: -28.7 %
Plasma Vol.: 1953 ml
Ideal Vol.: 2380 ml
Deficit: 426 ml
Devtn.: -17.9 %
Patient Blood Volume is: HYPOVOLEMIC
Normalized HCT is: 28.5%
Slope is: 0.00314
Standard Deviation is: 33.7 ml ( 1.159% )
------------------------------------------------------------------------------Normal
Mild
Moderate
BV, PV Deviation (+/- %):
0 to 8
>8 to 16
>16 to 24
RCV Deviation (%)
0 to 10
>10 to 20 >20 to 30
Severe
Extreme
>24 to 32
>32
>30 to 40
>40
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Normalized Peripheral Hematocrit
NPHct = Normalized Peripheral Hematocrit
 Is the change in the hematocrit that would occur by adjusting the
plasma volume so that the patient’s whole blood volume is at the
ideal blood volume.
NPHct = mBV x MPHCT
iBV
EXAMPLE #1
 Patient with ideal blood volume of 5,000 ml, measured blood
volume 4,000ml, hematocrit of 40%
4,000 x 40 = 32% (normalized hematocrit)
5,000
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Common Surrogate Markers
Hematocrit & Hemoglobin
Hypervolemic
Normal red cell
6500cc
Normovolemic
Normal red cell
Normovolemic
Anemia
5000cc
Hypovolemic
Anemia
5000cc
3750cc
Plasma Volume
Red Blood Cell
Volume
Hematocrit 45%
30%
30%
30%
Surrogate Markers Do Not Provide A Blood
Volume Measurement
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The Process – Why Five Data Points?
Mixing Time
Transudation
Accuracy



Tracer Concentration
x
Mix
BV
x
x
12
x
x
Measured BV (ln)
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Time (min)>>
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BVA in Septic Shock / Trauma
“Slope” reflects albumin transudation from vascular compartment
In normal subjects, the rate of movement of albumin across the capillary bed
into the lymphatic system is approximately 0.0025% per minute.
Calculated Intravascular Volume - ml
Increased slope suggests increased capillary permeability, a possible measure of
systemic inflammatory response, particularly in septic shock.
6400
6200
Important
Point!
Normal
Septic Sock
6000
An important point5800to remember is that a normal rate of transudation
does not necessarily5600rule out capillary damage. The reason for this is
that in situations where the intravascular albumin level drops and the
5400
extra vascular level increases, the decrease in albumin gradient may
5200
result in a stabilization
in the rate of transudation. This condition can be
5000
suspected in situations
where patients have low serum albumin levels.
The ultimate proof4800
of this hypothesis is to actually measure total body
0
12
18
24
30
36
albumin.
Time Point Of Sampling - Minutes
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Blood Volume Analyzer
Medical Conditions
1. Congestive Heart Failure
2. Syncope
3. Hypertension
4. Chronic Hypotension
5. Orthostatic Hypotension
6. POTS Syndrome
7. Polycythemia
9. Renal Dialysis
10. Pre/Post Surgical Volume Status
11. Blood Transfusion Assessment
12. Pre-Operative Hemodilution
13. Pre-Operative screening for
hypovolemia
14. Shock
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Clinical Application—Critical Care

ICU, CCU, SICU

Determine red blood cell and plasma volume status in critically ill
patients to guide treatment.
Identify hypovolemia in the presence of septic shock or peripheral
edema.
Differentiate dilutional from hypovolemic from normovolemic
anemia.
Differentiate IADHS from hyponatremia/renal salt wasting
syndrome.
Define a true intravascular volume status for patients receiving
ultrafiltration or CRRT therapy.




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Correlation Between Blood Volume and
Pulmonary Artery Catheter Measurements
Elisabeth Biuk-Aghai MD, Hideko Yamauchi MD, Mihae Yu MD, Hao Chih Ho MD, Alyssa Chapital MD, Danny
Takanishi MD
Department of Surgery, Division of Surgical Critical Care, Queen’s Medical Center, University of Hawaii,
Honolulu, HI






Purpose: to investigate the relationship between parameters obtained from a PAC and
simultaneous measurments of blood volume.
Twenty ICU patients contributed 29 simultaneous blood volume and PAC values.
Euvolemia was present in 11 of 29 instances, hypervolemia in 17 of 29, with 1 value
demonstrating hypovolemia.
Although there was a statistically significant relationship between PAOP and BV, BV
information resulted in different treatment in 6 out of 29 (21% of the time) with 4 of
the 6 times showing clinical improvement when BV information was used.
Regardless of the different ranges of the PAOP it was difficult to predict euvolemia
vs. hypervolemia. All patients had skin edema from shock and resuscitation and
assessment of intravascular blood volume was difficult.
Conclusion: There may be a role for BV measurment in patients after the acute
resuscitation when there is a clinical dilemma regarding blood volume treatment. Due
to the limitations of a retrospective study, we cannot infer outcomes until a
prospective randomized study is done.
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Relationships between Blood Volume
and Pulmonary Artery Occlusion Pressure
100%
90%
Hypervolemia
(n = 2)
Hypervolemia
(n = 9)
80%
70%
Hypervolemia
(n = 6)
60%
50%
40%
Euvolemia
(n = 4)
30%
Euvolemia
(n = 4)
20%
10%
Euvolemia
(n = 3)
Hypo (n=1)
0%
PAOP (mmHg)
<=12
(n = 6)
13-17
(n = 14)
>=18
(n = 9)
Although there was a statistically significant correlation between PAOP and BV, PAOP level (≤12 mm Hg, 13-18 mm Hg, or
>18 mm Hg) could not be used to predict euvolemia vs. hypervolemia. BV results led to different treatment in 6 out of 29
(21%) instances, with 4/6 times showing subsequent clinical improvement.
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How to order Blood Volume
Analysis?



Go to Power Chart
Enter “Whole Blood Volume” and you will be
presented with an existing orderable.
*In the comment section please put BVA
method.*
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