1. Management of Infants requiring Venovenous ECMO
Sixto F. Guiang, III
Dept. of Pediatrics
University of Minnesota

2. Neonatal ECMO = 73 % of all ECMO
VV ECMO = 20% of all Neonatal Pulmonary

3. University of Michigan
JAMA 2000;283:
N= 1000
Newborns N=586
Survival 88%
MAS 98%
CDH 68%
Others %
90% veno-venous
9% IVH

4. VV ECMO Respiratory Mode for all ages
Infants 20% of all Respiratory ECMO
Approximately 800 cases / yr
Pediatric 28% of all Respiratory ECMO
Approximately 200 cases / yr

5. Pediatric VV ECMO Pediatr Crit Care Med 2003;4:291-298
Single Center
N = 82 ECMO for Respiratory Failure
Venovenous 83%
Venoarterial 17%
Unable to place VV 43%

6. Pediatric VV ECMO Venovenous Dx ARDS RSV bronchiolitis Penumonia
Outcomes
Lower degree of respiratory failure
Shorter ECMO (212 hour vs 350 hours)
Higher survival (81% vs. 64%)

7. Pediatric VV ECMO
Pediatr Crit Care Med 2003;4:

8. Infusion limb
Drainage limb

9. Inclusion / Exclusion Guidelines- Same as VA
age of at least 34 weeks
Weight > kg
Potentially reversible process
Absence of uncorrectable cardiac defect
Absence of major intracranial hemorrhage
Absence of uncorrectable coagulopathy
Absence of lethal anomaly
Absence of prolonged mechanical ventilation with high ventilatory settings

10. Oxygenation Failure Criteria - VA and VV
Alveolar - arterial oxygen tension gradient
[ )-paCO2] - paO2
torr for greater than 4-12 hours
Oxygenation index
Mean Airway Pressure x FiO2 x 100/ paO2
> for greater than 1-6 hours

11. Oxygenation Failure Criteria - VA and VV
paO2
PaO2 < 35 for 2 hours
paO2 < 50 for 12 hours
Acute decompensation
paO2 < 30 torr

12. Myocardial Failure - VA Only
Refractory hypotension
Low cardiac output
pH <7.25 for 2 hours or greater
Uncontrolled metabolic acidosis secondary to hemodynamic insufficiency
Cardiac arrest - CPR

13. Additional Exclusion Criteria - Venovenous ECMO
Severe LV dysfunction
Severe hypotension
Cannulation during CPR
Desire to not have heparin
Bleeding

14. Additional Exclusion Criteria - Venovenous ECMO
Use of vasopressors is NOT a contraindication for VV ECMO
Isolated RV failure is NOT a contraindication for VV ECMO

15. Vasopresor - VV ECMO ASAIO Journal 2003;49:568-571
Neonatal ECMO-VA and VV
N = 43
Quantified inotropic support - Index
1 point = 1mcg/kgmin
Dopamine
Dobutamine
1 point = 0.01 mcg/kg/mon
Epinephrine
Norepinephrine

16. ASAIO Journal 2003;49:

17. ASAIO Journal 2003;49:

18. ASAIO Journal 2003;49:

19. Infants with Inotropic Score > 10
ASAIO Journal 2003;49:

20. ECMO Goals - VA and VV
Maintain adequate tissue oxygenation to allow recovery from short term cardiopulmonary failure
Adjust ventilator settings allowing for Lung Rest minimizing further ventilator /oxygen induced lung injury. Not necessarily lower settings

21. ECMO Modes Venoarterial - VA Blood drains-venous system
Blood returns-arterial system
Complete cardiopulmonary support
Venovenous - VV
Blood returns-venous system
Pulmonary support only

22. Advantages of VA ECMO Able to give full cardiopulmonary support
No mixing of arterial / venous blood
Good oxygenation at low ECMO flows
Allows for total lung rest

23. Disadvantages of VA ECMO
Ligation of the right carotid artery
Nonpulsatile arterial blood flow
Suboptimal conditions for LV function
Low preload
High afterload
High wall stress
Low coronary oxygenation

24. Disadvantages of VA ECMO
Systemic emboli
Air
thrombus

25. Advantages of VV ECMO No ligation of carotid artery
Normal pulsatile blood flow
Optimize LV performance
More preload
Less afterload
Better coronary oxygenation
Less ventricular wall stress
No systemic emboli

26. Disadvantages of VV ECMO
Need a functioning LV
Mixing of blood lower arterial saturation
Need increased ECMO flow
Need higher hemoglobin
Need to place a larger cannula
More difficulty monitoring adequacy of oxygen delivery
Recirculation of ECMO flow

27. Disadvantages of VV ECMO
May need to convert to VA
Need to be fully heparinized
Cannula cannot be heparin bonded

28. VV ECMO -Double lumen Newborns >90% of VV ECMO - Double lumen
12F and 15F OriGen
Pediatric
35% of VV ECMO -double lumen
18F - largest OriGen cannula
65% internal jugular, femoral, sapphenous

29. VV ECMO -Double lumen Cannula site
Internal jugular vein (15F double lumen- preferred)
Cannula tip low in the right atrium

31. Drainage
Infusion
High lateral RA
Mid Medial RA
Low lateral RA
Endhole

34. Optimal Cannula Placement
Adequate size
Correct depth
Low Right Atrium
Correct Rotation
Label visible
Drainage limb (Blue) posterior
Infusion limb (Red) anterior
Vertical orientation
Head - midline
No Kinks

36. Recirculation
Oxygenated ECMO blood returning to the ECMO circuit immediately after infusion

37. Recirculation factors
Head /cannula position
Changes with head rotation
Changes in lung volume / relative position of the heart and cannula
ECMO flow
Right atrial size / intravascular volume
RV contractility

38. ECMO blood flow
to baby - 160
ECMO Flow reads 200

39. ECMO blood flow
to baby - 250
ECMO Flow reads 500

40. ECMO Flow -Recirculation
More ECMO flow will always increase recirculation
More ECMO flow may either
Increase blood flow to baby
Decrease blood flow to baby

41. VA ECMO ECMO flow rate is proportional to the level of support
More flow More support
Always advantageous if more flow is possible
More ECMO flow will always increase SvO2

42. Pulmonary Support - VV
Net ECMO blood flow of infant = measure ECMO flow - recirculation flow
ECMO flow (flow probe) DOES NOT indicate level of support
SvO2 DOES NOT reflect level of systemic oxygen delivery

43. Circulatory Support Net flow to baby assessed by Infant color
Infant arterial saturation and PaO2

44. Assessment of Recirculation
More recirculation if
Decreasing baby arterial sat or PaO2
Increasing SvO2 on ECMO circuit
Decreasing color difference on drainage and infusion limbs of circuit

45. Reducing Recirculation
Adjusting relative cannula position
Head position
Lung inflation
Decrease ECMO flow
Increase intravascular volume
Increase RV contractility
Volume
Vasopressors
Pulmonary vasodilators

46. VV - VA Conversion Needed if 10-15% of cases
Hemodynamic support is inadequate
Respiratory support is inadequate
More problematic when ultrafiltration is used

47. VV ECMO - Specific Issues
ECMO Prime
Must have added heparin
Must have Ca added
Ionized Ca on circuit must be checked prior to cannulation
Potassium must be checked

48. Heparin If no heparin added
Addition of Ca binds citrate of blood products
Loss of anticoagulant activity
Acute clotting of the entire circuit
Need to prime another circuit

49. Calcium If no calcium added
Acute hypocalcemia - Ca binds to citrate of blood products
Loss of LV and RV contractility
Acute hypotension
Cardiac arrest

50. Potasium If potassium in prime is not checked
Possible higher serum K from the stored PRBC
Acute hyperkalemia
Arrythmia
Cardiac arrest

51. Head / Cannula Position
Distal tip low in RA
Head in the midline with vertical orientation of the drainage and infusion limbs
RA drainage ports
Lateral
Infusion ports
Medial

52. Keys to Management VV ECMO- DL
Need to think in terms of NET blood flow to the baby
Cannot quantify NET flow
SvO2 is not indicative of adequacy of systemic oxygen delivery
Indirectly assessed with SaO2 and PaO2 on the infant

53. To Improve oxygenation
Give PRBC
Increase ECMO flow
Decrease recirculation
Check cannula position
Increase ntravascular volume
Increase RV contractility

54. Rest Ventilator Settings
Pressures - similar to VA
FiO2 - able to wean to RA frequently
Better myocardial oxygenation via ECMO flow than VA

55. Jugular venous drainage
11% of all double lumen VV
Small study suggested decrease IVH
Reduced cerebral venous pressure
Advantage
Additional drainage facilities flow
2 site venous drainage lessens recirculation on VV ECMO
Improved oxygen delivery
Enables venous oxygen saturation monitoring on VV ECMO

56. Jugular Venous Drainage Cephalad Cannula
J Pediatr Surg 2004;39:
Review of ELSO database
Neonatal Respiratory Failure VV ECMO
N = 2471
96% VV double lumem alone
3.7% with jugular venous drainage
Similar Outcomes

57. Operating Parameters SaO2 - 85-95% PaO2 40-65 torr
Blood pressure - similar to VA
ECMO flows ml/kg/min
HgB g/dl

58. Weaning of ECMO - VV No clamp out needed Increase ventilator
Decrease sweep gas flow rate and FiO2
Sweep gas flow can be completely stopped
SvO2 will reflect mixed venous saturation
No recirculation

59. Gas
Flow

60. NO Gas
Flow

61. VV ECMO Outcomes
Generally slightly better than VA, but slightly different patient populations
Hemodynamically more stable
Less exposure to CPR
Better survival
Shorter duration of ECMO
Conversion VV to VA
12%

62. VA - VV Comparison studies
J Peds Surg1993;28:
Multicenter data
N=243
VA = 135
VV = 108
Similar survival
10% conversion to VA
Shorter runs
Less Neurologic complications