Transcript Vascular Access The Alpha and Omega of CRRT Rick Hackbarth MD

Vascular Access
The Alpha and Omega of CRRT
Rick Hackbarth MD
Division of Pediatric Critical Care
Grand Rapids, Michigan
Vascular Access Wisdom
“If you don’t have good access you might as
well go home!”
Vascular Access
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The portal from patient to circuit
Affects circuit life
 Lost circuits may expose patients to more
transfusions and frustrates staff
Affects clearance
 Lower blood flow rates and hemofiltration rates
 More downtime
Vascular Access
Two questions to be answered
What size catheter to use?
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Where to put it?
Vascular Access Wisdom
“Size matters!”
Vascular Access Wisdom
“Size matters!”
Vascular Access
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Poiseuille’s Law-
Q = ∆Pπr4
8l
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Smaller diameters offer greater resistance to flow
Longer lengths offer greater resistance to flow
Decreasing the diameter by 1/5th is the same as
doubling the length (roughly a 2 French size
difference)
Vascular Access
ppCRRT Registry Access Study
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13 Pediatric Institutions
376 patients
1574 circuits
Circuit survival by Catheter size, site, and modality
Hackbarth R et al: IJAIO 30:1116-21, 2007
Vascular Access
Figure 2: Mean Patient Weight vs Catheter Size
100
80
60
Kg
40
20
0
5 French
7 French
8 French
9 French
10 French
Catheter Size
Hackbarth R et al: IJAIO 30:1116-21, 2007
11.5
French
12.5
French
Number of Patients
% Survival at 60
hours 
Catheter Size*
5
7
8
9
10
11.5
12.5
6
57
65
35
46
71
64
0 (p <0 .0000)
43 (p < 0.002 )
55 (NS)
51 (p < 0.002 )
53 (NS)
57 (NS)
60 (NS)
Insertion Site
Internal Jugular
Subclavian
Femoral
58
31
260
60 (p < 0.05 )
51 (NS)
52 (NS)
Hackbarth R et al: IJAIO 30:1116-21, 2007
Vascular Access
1st 72 hrs of circuit
life only
Shorter life span
for 7 and 9 French
catheters (p< 0.002)
Hackbarth R et al: IJAIO 30:1116-21, 2007
Vascular Access Wisdom
“Location, location, location!”
Vascular Access
“Location, location, location!”
Options:
 Femoral vein
 Subclavian vein
 Internal Jugular vein
Figure 1: Catheter Location by Size
100
90
80
70
60
Femoral
%
IJ
50
Subclavian
Unknown
40
30
20
10
0
5 French
7 French
8 French
9 French
Catheter Size
Hackbarth R et al: IJAIO 30:1116-21, 2007
10 French
11.5 French
12.5 French
Vascular Access
“Location, location, location!”
Femoral Vein
Pros:
 Accessible under almost any conditions
 Easier to maintain hemostasis
Cons:
 Potential for kinking
 More recirculation
 Thrombosis
 Problematic flow with increased abdominal pressures
Vascular Access
“Location, location, location!”
Subclavian Vein
Pros:
 Shorter catheter/better flow
 Less recirculation
Cons:
 Potential for kinking
 Difficult hemostasis
 Potential for venous narrowing
 Less accessible with cervical or trauma
Vascular Access
“Location, location, location!”
Internal Jugular Vein
Pros:
 Shorter catheter/better flow
 Less recirculation
Cons:
 Difficult hemostasis
 Less accessible with cervical trauma
 Catheter length problematic in small infants
Vascular Access
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Highly variable position of the IJ vein
Ultrasound can be quite helpful
Maecken T et al: CCM 35: S178-85, 2007
Number of Patients
% Survival at 60
hours 
Catheter Size*
5
7
8
9
10
11.5
12.5
6
57
65
35
46
71
64
0 (p <0 .0000)
43 (p < 0.002 )
55 (NS)
51 (p < 0.002 )
53 (NS)
57 (NS)
60 (NS)
Insertion Site
Internal Jugular
Subclavian
Femoral
58
31
260
60 (p < 0.05 )
51 (NS)
52 (NS)
Hackbarth R et al: IJAIO 30:1116-21, 2007
Vascular Access
Survival favors IJ
Location (p< 0.05)
Hackbarth R et al: IJAIO 30:1116-21, 2007
Figure 1: Catheter Location by Size
100
90
80
70
60
Femoral
%
IJ
50
Subclavian
Unknown
40
30
20
10
0
5 French
7 French
8 French
9 French
Catheter Size
Hackbarth R et al: IJAIO 30:1116-21, 2007
10 French
11.5 French
12.5 French
Vascular Access Wisdom
“It’s déjà vu all over again.”
Vascular Access
Recirculation
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More of an issue in femoral catheters
especially shorter than 20 cm
Is this really a practical concern with 24/7
clearance?
Catheter proximity may be a bigger issue
Vascular Access
Note the relationship of the line tips.
Vascular Access
Catheter proximity
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Inadvertent removal of infusions
Circuit clotting with platelet transfusions
Entraining calcium into the circuit
Vascular Access Wisdom
“You can’t always get what you want, but you
might get what you need!”
Vascular Access
Catheter Specifications
French
Size
5
7
8
Flow Rate
(ml/min)
?
80-100
150-200 250-300 285-330
10
12
Vascular Access
Catheter Specifications
French
Size
5
7
8
10
12
Diameter
(mm)
1.67
2.3
2.7
3.3
4.0
Vascular Access
Vessel diameter vs Age
3
2.5
2
cm
Femoral
IVC
IJ
1.5
1
0.5
0
0
2
4
6
8
10
13
16
19
Years
Steinberg et al: Catheterization and Cardiovascular Diagnosis
27: 197-201, 1992
Vascular Access
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Poiseuille’s Law-
Q = ∆Pπr4
8l
Vascular Access
Relative Resistance to IVC Blood Flow
Relative Resistance
6
4
Infant
2 year old
6 year old
10 year old
16 year old
2
0
5
7
8
10
Catheter Size (French)
12
Vascular Access
Relative Resistance to IVC Blood Flow
Relative Resistance
6
4
4kg
12 kg
20 kg
30 kg
2
60 kg
0
5
7
8
10
Catheter Size (French)
12
Vascular Access
Differing Perspectives on the ICU Patient
It was six men of Indostan
To learning much inclined,
Who went to see the Elephant
(Though all of them were blind),
That each by observation
Might satisfy his mind.
John Godfrey Saxe
The Blind Men and the Elephant
Vascular Access
Differing Perspectives on the ICU Patient
And so these men of Indostan
Disputed loud and long,
Each in his own opinion
Exceeding stiff and strong,
Though each was partly in the right,
And all were in the wrong!
John Godfrey Saxe
The Blind Men and the Elephant
Vascular Access
Vascular Access
Vascular Access
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Vascular Access
Two questions to be answered
What size catheter to use?
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Where to put it?
Vascular Access
Where should the catheter go?
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What sites are available?
Are there anatomic or physiologic constraints?
Which vessel is optimal for the catheter size?
Is the patient coagulopathic?
Consider patient mobility and risk of kinking.
Is there elevated intra-abdominal pressure?
Vascular Access
Where should the catheter go?
Answer: Internal Jugular vein if possible
Vascular Access
What size catheter should we use?
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Don’t use a 5 French catheter.
Choose the largest diameter that is safe for the child.
Choose the smallest catheter that will achieve the
necessary flow easily.
Choose the the minimum length to position the tip for
optimal flow.
In the femoral position, longer catheters will minimize
recirculation
PATIENT SIZE
CATHETER SIZE &
SITE OF INSERTION
SOURCE
NEONATE
Single-lumen 5 Fr (COOK)
Femoral artery or vein
Dual-Lumen 7.0 French
Femoral vein
(COOK/MEDCOMP)
3-6 KG
6-30 KG
>15-KG
>30 KG
>30 KG
Dual-Lumen 7.0 French
Internal/External-Jugular,
(COOK/MEDCOMP)
Subclavian or Femoral vein
Triple-Lumen 7.0 Fr
Internal/External-Jugular,
(MEDCOMP)
Subclavian or Femoral vein
Dual-Lumen 8.0 French
Internal/External-Jugular,
(KENDALL/ARROW)
Subclavian or Femoral vein
Dual-Lumen 9.0 French
Internal/External-Jugular,
(MEDCOMP)
Subclavian or Femoral vein
Dual-Lumen 10.0 French
Internal/External-Jugular,
(KENDALL, ARROW)
Subclavian or Femoral vein
Triple-Lumen 12 French
Internal/External-Jugular,
(KENDALL/ ARROW)
Subclavian or Femoral vein
Disney Wisdom
“I would rather entertain and hope that people
learned something than educate people and
hope they were entertained.”