36

1. 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)

2. Access
 If you don’t have it you might as well go
home.
 This is the most important aspect of CRRT
therapy.
 Adequacy.
 Filter life.
 Increased blood loss.
 Staff satisfaction.

3. Vascular Access
 Ideal Catheter Characteristics
 Easy Insertion
 Permits Adequate Blood Flow without Vessel Damage
 Minimal Technical Flaws
 High Recirculation Rate
 Kinking
 Shorter and Larger Catheters
SIZE DOES MATTER
 Lower Resistance
 Improved Bloodflow

4. Vascular Access for CRRT
 Match catheter size to patient size and
anatomical site
 One dual- or triple-lumen or two single lumen
uncuffed catheters
 Sites
 femoral
 internal jugular
 avoid sub-clavian vein if possible

5. Pediatric CRRT Vascular Access:
Performance = Blood Flow
 Minimum 30 to 50 ml/min to minimize access
and filter clotting
 Maximum rate of 400 ml/min/1.73m2 or
 10-12 ml/kg/min in neonates and infants
 4-6 ml/kg/min in children
 2-4 ml/kg/min in adolescents

6. Vascular Access
Two questions to be answered-
 What size catheter to use?
 Where to put it?

7. Femoral vs IJ catheter performance
 26 femoral
 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

8. Femoral vs IJ catheter performance
Type Number
Qb
(ml/min)
Recirculation(%) 95% CI
Femoral 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
Jugular 13 226.4 0.4* -0.1 to 1.0
Little et al: AJKD 36:1135-9, 2000
* p<0.001
** p<0.007

9. Vascular Access
ppCRRT Registry Access Study
 13 Pediatric Institutions
 376 patients
 1574 circuits
 Circuit survival by Catheter size, site, and modality
Hackbarth R et al: IJAIO 30:1116-21, 2007

10. Vascular Access
Figure 2: Mean Patient Weight vs Catheter Size
0
20
40
60
80
100
5 French 7 French 8 French 9 French 10 French 11.5
French
12.5
French
Catheter Size
Kg
Hackbarth R et al: IJAIO 30:1116-21, 2007

11. Number of Patients
% Survival at 60
hours 
Catheter Size*
5 6 0 (p <0.0000)
7 57 43 (p < 0.002)
8 65 55 (NS)
9 35 51 (p < 0.002)
10 46 53 (NS)
11.5 71 57 (NS)
12.5 64 60 (NS)
Insertion Site
Internal Jugular 58 60 (p < 0.05)
Subclavian 31 51 (NS)
Femoral 260 52 (NS)
Hackbarth R et al: IJAIO 30:1116-21, 2007

12. Vascular Access
Hackbarth R et al: IJAIO 30:1116-21, 2007
Shorter life span
for 7 and 9 French
catheters (p< 0.002)
1st 72 hrs of circuit
life only

13. Figure 1: Catheter Location by Size
0
10
20
30
40
50
60
70
80
90
100
5 French 7 French 8 French 9 French 10 French 11.5 French 12.5 French
Catheter Size
%
Femoral
IJ
Subclavian
Unknown
Hackbarth R et al: IJAIO 30:1116-21, 2007

14. 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

15. 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

16. 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

17. Number of Patients
% Survival at 60
hours 
Catheter Size*
5 6 0 (p <0.0000)
7 57 43 (p < 0.002)
8 65 55 (NS)
9 35 51 (p < 0.002)
10 46 53 (NS)
11.5 71 57 (NS)
12.5 64 60 (NS)
Insertion Site
Internal Jugular 58 60 (p < 0.05)
Subclavian 31 51 (NS)
Femoral 260 52 (NS)
Hackbarth R et al: IJAIO 30:1116-21, 2007

18. Vascular Access
Hackbarth R et al: IJAIO 30:1116-21, 2007
Survival favors IJ
Location (p< 0.05)

19. Vascular Access
Catheter proximity
 Inadvertent removal of infusions
 Circuit clotting with platelet transfusions
 Entraining calcium into the circuit

20. Vascular Access
Note the relationship of the line tips.

21. Vascular Access for Pediatric
CRRT
(Hackbarth et al, CRRT 2005)
 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

22.  7 Fr dual lumen with clot in 50%
 Avg BFR 27 mls/min
 8 Fr dual lumen with clot in 20%
 Avg BFR 73 mls/min
 12 Fr triple lumen with no clot in any
 Avg BFR 127 mls/min
 This was used in in all children > 35 kg
Vascular Access for Pediatric
CRRT
(Hackbarth et al, CRRT 2005)

23. Triple vs Dual in Peds RRT
 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?

24. Vascular Access
What size catheter should we use?
 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

25. Vascular Access
Where should the catheter go?
 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?

26. Vascular Access
Where should the catheter go?
Answer: Internal Jugular vein if possible

27. PATIENT SIZE CATHETER SIZE &
SOURCE
SITE OF INSERTION
NEONATE Single-lumen 5 Fr (COOK) Femoral artery or vein
Dual-Lumen 7.0 French
(COOK/MEDCOMP)
Femoral vein
3-6 KG Dual-Lumen 7.0 French
(COOK/MEDCOMP)
Internal/External-Jugular,
Subclavian or Femoral vein
Triple-Lumen 7.0 Fr
(MEDCOMP)
Internal/External-Jugular,
Subclavian or Femoral vein
6-30 KG Dual-Lumen 8.0 French
(KENDALL/ARROW)
Internal/External-Jugular,
Subclavian or Femoral vein
>15-KG Dual-Lumen 9.0 French
(MEDCOMP)
Internal/External-Jugular,
Subclavian or Femoral vein
>30 KG Dual-Lumen 10.0 French
(KENDALL, ARROW)
Internal/External-Jugular,
Subclavian or Femoral vein
>30 KG Triple-Lumen 12 French
(KENDALL/ ARROW)
Internal/External-Jugular,
Subclavian or Femoral vein