1. ECMO and CRRT Matthew L. Paden, MD
Assistant Professor of Pediatric Critical Care
Director, Pediatric ECMO

2. Disclosures Funded by NIH/FDA for CRRT/ECMO device development
Everything in ECMO is off label use
I’m a believer…

3. Objectives Discuss usage cases for concomitant ECMO/CRRT
Description of recent common changes in ECMO configurations
Discuss technical aspects of concomitant ECMO/CRRT

4. Common indications Survey of ELSO centers Fluid overload (43%)
AKI (35%)
Prevention of fluid overload (16%)
Electrolyte abnormalities (4%)
Fleming GM, et al. ASAIO J (4):

5. ECMO and Urine Output 30 consecutive neonates meeting ECMO criteria –
18 VV ECMO, 12 conventional management
Only looked at first 108 hours
Patients who went onto ECMO had:
Greater fluid overload
Lower UOP
Higher BUN
Higher creatinine
No difference in BP, protein intake, albumin, or diuretics
Roy BJ, Cornish JD, Clark RH. Pediatrics 1995;95(4):573-8

6. ECMO and Urine Output

7. Neonates on ECMO UCLA – 17 consecutive neonates on VA ECMO
Hypothesis –
Pulmonary HTN goes away quickly
Pulmonary edema secondary to Starling forces keeps you on ECMO
All got diuretics to maintain 3 cc/kg/hour
Kelley RE, et al. Journal of Pediatric Surgery, Vol 26(9);1991:

8. Neonates on ECMO Results As weight reduces, ECMO flow reduces
Kelley RE, et al. Journal of Pediatric Surgery, Vol 26(9);1991:

9. ELSO Guidelines
The goal of fluid management is to return the extracellular fluid volume to normal (dry weight) and maintain it there.
…spontaneous or pharmacologic diuresis should be instituted until patient is close to dry weight and edema has cleared. This will enhance recovery from heart or lung failure and decrease the time on ECLS.
As with all critically ill patients, full caloric and protein nutritional support is essential.

10. ELSO Guidelines
The hourly fluid balance goal should be set and maintained until normal extracellular fluid volume is reached (no systemic edema, within 5% of “dry” weight). Renal replacement therapy use to enhance fluid removal allowing adequate nutritional support is often performed.
Despite the literature surrounding fluid overload (>10%) as a risk factor for death, review of the ELSO registry also finds that use of renal replacement therapy is also a risk factor for poor outcome.
Even if acute renal failure occurs with ECLS, resolution in survivors occurs in >90% of patients without need for long-term dialysis.

11. Preventing Fluid Overload
How many of you would start CRRT on an ECMO patient with a normal creatinine and no fluid overload?

12. AKI and ECMO Neonates - 25% (Askenazi 2011)
ELSO registry ~8000 non-cardiac neonates
Creatinine > 1.5 or RRT
Congenital diaphragmatic hernia - 71% (Gadepalli 2011)
Congenital hearts - 72% (Smith 2009)
Pediatric respiratory - 63% (ELSO DB 2011)
Adult cardiac – 81% (RIFLE)/85% (AKIN)
Note limitations of single center / ELSO database / Different definitions of AKI

13. CHOA Ped Respiratory ECMO 6/2010-1/2012
Emergency airway for foreign body
Cancer – APML
RSV – retroperitoneal hemorrhage
Goodpasteur’s syndrome
Pertussis x 2
Influenza H1N1
Asthma x 2
RSV
Cancer – ALL
Smoke inhalation
Wegener’s granulomatosis x 2
Near drowning
Post-partum ARDS
Chronic granulomatous disease
Hemophagic lymphohistiocytosis
RSV + MRSA
Cancer – AML
Septic shock x 2
Multiple organ failure
Pulmonary embolus x 2

14. Concomitant ECMO/CRRT Renal Outcomes
University of Michigan
35 CRRT/ECMO patients – 15 survivors (43%)
14/15 (93%) with full renal recovery at D/C
Wegeners – ultimately transplanted
Children’s Healthcare of Atlanta
154 CRRT/ECMO patients - 68 survivors (44%)
65/68 (96%) with full renal recovery at D/C
1 nosocomial enterococcus sepsis at transfer – normal 1 month later
2 primary renal disease (Wegeners/polyangiitis) – Cr 13.7/6.5
One ultimately transplanted / one with elevated Cr, no RRT

15. “ECMO as a platform” Enhances cardiorespiratory stability
Reduction of inotropes/vasoactive agents
Provides adequate vascular access to allow additional organ support therapies
CRRT, plasma exchange, etc.
“Buys time” to allow new approaches/therapies to work
Antibiotics, reduction of immunosuppression
Concept of “organ rest”
Reduces inflammatory response from lung injury

16. New equipment PMP Oxygenators Centrifugal pumps Smaller prime volume
Shorter blood path
Less pressure drop across the membrane
Centrifugal pumps
New levitating impeller based designs
Continuous flow - afterload dependent
Eliminates risk of raceway rupture
Risk of negative pressure generation

17. Change in ECMO Equipment
2002 (Lawson et al. JECT 2004;36:16)
95% roller head, 5% centrifugal
97% silicone, 0% PMP
2008 (Lawson et al. JECT 2008;40:166)
82.5% roller head, 17.5% centrifugal
67% silicone, 14% PMP
2011 (P Rycus, personal communication)
44% roller head, 56% centrifugal
35% silicone, 65% PMP

18. ECMO pumps Traditional design ECMO 2.0 Roller head pump Complex
Positive pressure venous limb
ECMO 2.0
Centrifugal pump
Simplified
Negative pressure venous limb

19. Traditional design

20. ECMO 2.0

21. CVVH/ECMO “In-line” Schematic
IV pumps
Regulate UF production
Deliver RF
Urometer to measure UF production
Inexpensive
Inaccurate

22. Pediatric ECMO / In-line CRRT Warning
Sucosky et al., J Med Devices (2), 2008
IV pumps
Your I/O’s are not accurate
Delivers less replacement fluid than ordered.
10 kg child with 300 mL/hour UF rate – negative 288 mL per day (28 ml/kg)
45 kg adolescent with 2000 ml/hour UF rate – negative 1.9 L/day (42 ml/kg)

23. ECMO/CRRT Traditional Design Schematic
POSITIVE
VENOUS
PRESSURE
IV pump/urometer based system
hemofilter
membrane oxygenator
roller pump
Commercial CRRT system
ECMO bladder

24. ECMO 2.0/CRRT Schematic NEGATIVE VENOUS PRESSURE
Kidney International. 2009;76:1289–1292.

25. Managing pressure
No CRRT device is FDA approved/designed for use with ECMO
Pressure alarms are common
Too negative/positive drain pressures
Too negative/positive return pressures
No uniform solution currently exists
Changing/removing alarm parameters
Adding flow restriction via tubing/clamps
Altering circuit entry points
A need exists for a CRRT device designed for use with other extracorporeal devices