Vascular Access Considerations and Options for Pediatric CRRT

Stuart L. Goldstein, MD

Vascular Access: Overview

• Required performance characteristics

• Size and site options– Pros and cons of femoral vs IJ– Recirculation issues

• Special situations– LVAD/ECMO– Citrate anticoagulation

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

Venous 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

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

(ARROW, KENDALL)

Internal/External-Jugular,

Subclavian or Femoral vein

>30 KG Triple-Lumen 12.5 French

(ARROW, KENDALL)

Internal/External-Jugular,

Subclavian or Femoral vein

Vascular Access for Pediatric CRRT: Pros and Cons of Femoral Site

• Relatively larger vessel may allow for– larger catheter

– higher flows

• Ease of placement

• No risk of pneumothorax

• Preserve potential future vessels for chronic HD

• Shorter femoral catheters with increased % recirculation

• Poor performance in patients with ascites/increased abdominal pressure

• Trauma to venous anastamosis site for future transplant

PROS CONS

Vascular Access for Pediatric CRRT: Pros and Cons of IJ/SCV Site

• Tip placement in right atrium decreases recirculation

• Not affected by ascites• Preserve potential vein

needed for transplant

• SCV stenosis (SCV)

• Superior vena cava syndrome

• Risk of pneumothorax in patients with high PEEP

• Trauma to veins needed potentially for future HD access

PROS CONS

Femoral versus 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

Femoral versus 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

Femoral versus IJ catheter performance: Pediatrics

103 102 118 119

219

174

3 4

0

50

100

150

200

250

BFR(mls/min)

Venous P(mm Hg)

Arterial P(mm Hg)

% Recirc

IJ/SC

Femoral

P value NS NS NS NS

(Gardner et al, CRRT 1997Quinton 8 Fr; n = 20; 120 Treatments)

Venous Access for CRRT:Special Situation/LVAD-ECMO

• Parallel to other extra-corporeal circuit– ECMO– LVAD

• Blood prime• High ECMO/LVAD flows can cause

minimal negative “arterial” pressure– access disconnect alarms– arterial screw clamp to cause negative pressure

CRRT in LVAD circuit

LVAD

CRRT

Vascular Access for Pediatric CRRT:Some Final Thoughts

• 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?