Vascular Access for CRRT
Timothy E Bunchman
Professor & Director
Helen DeVos Children’s Hospital
Grand Rapids, MI
(Thanks to Rick Hackbarth MD for his help
and slides)
Access
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If you don’t have it you might as well go
home.
This is the most important aspect of CRRT
therapy.
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Adequacy.
Filter life.
Increased blood loss.
Staff satisfaction.
Vascular Access
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Ideal Catheter Characteristics
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Easy Insertion
Permits Adequate Blood Flow without Vessel Damage
Minimal Technical Flaws
 High Recirculation Rate
 Kinking
Shorter and Larger Catheters
SIZE DOES MATTER
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Lower Resistance
Improved Bloodflow
Vascular Access for CRRT
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Match catheter size to patient size and
anatomical site
One dual- or triple-lumen or two single lumen
uncuffed catheters
Sites
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femoral
internal jugular
avoid sub-clavian vein if possible
Pediatric CRRT Vascular Access:
Performance = Blood Flow
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Minimum 30 to 50 ml/min to minimize access
and filter clotting
Maximum rate of 400 ml/min/1.73m2 or
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10-12 ml/kg/min in neonates and infants
4-6 ml/kg/min in children
2-4 ml/kg/min in adolescents
Vascular Access
Two questions to be answered
What size catheter to use?
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Where to put it?
Femoral vs IJ catheter performance
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26 femoral
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19 > 20 cm
7 < 20cm
13 IJ
Qb 250 ml/min (ultrasound dilution)
Recirculation measurement by ultrasound
dilution method
Little et al: AJKD 36:1135-9, 2000
Femoral vs IJ catheter performance
Type
Femoral
Number
Qb
Recirculation(%)
(ml/min)
95% CI
26
237.1
13.1*
7.6 to 18.6
> 20cm
19
233.3
8.5**
2.9 to 13.7
< 20cm
7
247.5
26.3**
17.1 to
35.5
13
226.4
0.4*
-0.1 to 1.0
Jugular
* p<0.001
** p<0.007
Little et al: AJKD 36:1135-9, 2000
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 C atheter 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 Pati ents
% Survival a t 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 Jugu lar
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
Figure 1: Catheter Location by Size
100
90
80
70
60
Femoral
%
IJ
50
Subc lavian
U nknown
40
30
20
10
0
5 F renc h
7 F renc h
8 F renc h
9 F renc h
Cathet er Size
Hackbarth R et al: IJAIO 30:1116-21, 2007
1 0 F renc h
1 1 .5 Frenc h 1 2 .5 Frenc h
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 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
Number of Pati ents
% Survival a t 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 Jugu lar
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
Vascular Access
Catheter proximity
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Inadvertent removal of infusions
Circuit clotting with platelet transfusions
Entraining calcium into the circuit
Vascular Access
Note the relationship of the line tips.
Vascular Access for Pediatric
CRRT
(Hackbarth et al, CRRT 2005)
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Children on CRRT/24 months
Age range 2 days – 18 yrs
Wt range 2.5-78 Kg
Citrate anticoagulation
Avg circuit life 3.1 days (0.3-11 days)
Access was size dependent
Vascular Access for Pediatric
CRRT
(Hackbarth et al, CRRT 2005)
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7 Fr dual lumen with clot in 50%
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8 Fr dual lumen with clot in 20%
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Avg BFR 27 mls/min
Avg BFR 73 mls/min
12 Fr triple lumen with no clot in any
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Avg BFR 127 mls/min
This was used in in all children > 35 kg
Triple vs Dual in Peds RRT
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5 year experience with Pediatric CRRT using
the “pigtail” as the CaCL replacement
If not for citrate CRRT also serves as an
added central line for other med/TPN infusion
What staff at bedside ever has sufficient
central access?
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
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
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