Transcript Access in Pediatric CRRT

Access in Pediatric
CRRT
Patrick D Brophy MD
Pediatric Nephrology, Dialysis & Transplantation
CS Mott Children’s Hospital
University of Michigan
From Gina
The System is Down
due to poor Access!
My first choice is….
Access
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If you don’t have it you might as well go
home.
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This is the most important aspect of CVVH
therapy.
Adequacy.
 Filter life.
 Increased blood loss.
 Staff satisfaction.
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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
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
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,
(ARROW, KENDALL)
Subclavian or Femoral vein
Triple-Lumen 12.5 French
Internal/External-Jugular,
(ARROW, KENDALL)
Subclavian or Femoral vein
Venous 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
femoral
 internal jugular
 avoid sub-clavian vein if possible
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Catheter Position
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No Right or Wrong Choice of Placement
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FACTORS
Clinical expertise
 Body Habitus
 Other catheters (Citrate anticoag-triple preferred)
 Coagulopathy
 Intra-abdominal distension
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Catheter Position
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Internal Jugular-Right- aim for RA to secure
adequate BFR
Subclavian-Patient mobility? Most frequent site
of inadequate performance -catheter curves and
abutts against SVC-Vein collapses against
catheter due to positional/volume change
Femoral- optimal position in tip of IVC
Vascular Access for Pediatric CRRT:
Pros and Cons of Femoral Site
PROS
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Relatively larger vessel may
allow for
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larger catheter
higher flows
Ease of placement
No risk of pneumothorax
Preserve potential future
vessels for chronic HD
CONS
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Shorter femoral catheters with
increased % recirculation
Poor performance in patients
with ascites/increased
abdominal pressure
Trauma to venous anastamosis
site for future transplant
Vascular Access for Pediatric CRRT:
Pros and Cons of IJ/SCV Site
PROS
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Tip placement in right atrium
decreases recirculation
Not affected by ascites
Preserve potential vein
needed for transplant
CONS
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SCV stenosis (SCV)
Superior vena cava syndrome
Risk of pneumothorax in
patients with high PEEP
Trauma to veins needed
potentially for future HD
access
Femoral versus IJ catheter performance
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26 femoral
19 > 20 cm
 7 < 20cm
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13 IJ
Qb 250 ml/min (ultrasound dilution)
Recirculation measurement by ultrasound
dilution method
Little et al: AJKD 36:1135-9, 2000
Femoral versus IJ catheter
performance
Number
Qb
(ml/min)
Recirculation(%)
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
Type
Femoral
Jugular
* p<0.001
** p<0.007
Little et al: AJKD 36:1135-9, 2000
Troubleshooting Access
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How can you tell if you
have a problem before
starting?
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What if you have
problems during
treatment?
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Check placement first,
then use syringe to test
resistance and blood
return.
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Check line for kink, then
assess patients position
or need for sedation.
Access
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Clotting or sluggish catheter.
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tPA (tissue plasminogen activator).
(Spry et al., Dialysis&Transplantation. Jan. 2001).
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Normal saline flush.
Reason to replace catheter.
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Clotted catheter with no response to tPA.
Exit site blood leakage with no response to pressure dressing.
Severe kinked catheter.
Bad re-circulation issues.
Pressures
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Arterial or outflow pressures
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High negative pressure = access problem.
High positive pressure = filter problem.
Moderate to high positive pressure + high return (venous) pressure =
access problem.
Venous or return pressures
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Moderate to high positive pressure + high arterial pressure = filter
problem.
High return pressure + moderate arterial pressure = access
Vascular Access for Pediatric CRRT:
Some Final Thoughts
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Catheters with poor function will function poorly…
over and over and over and over
Balance between surgical/ICU expertise (preference?)
and the necessary evils dictated by the patient
 high PEEP… femoral catheter?
 massive ascites… IJ catheter?
 available sites… are there any?
Which vessel are you willing to traumatize?
Conclusions
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Poor Access-- May as well stop
Choice- patient size and optimal flows
Site- IJ/Femoral -recommended
Care- Local standard + Lock issues- heparin
Troubleshooting- anticipate, what is the machine
saying?
Happy Hemofiltering!
Thanks!
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Stu Goldstein
Tim Bunchman
Theresa Mottes
Tim Kudelka
Betsy Adams
Tammy Kelly
Robin Nievaard