1. Donor Organ Machine Perfusion - Application of An Hemoglobin-based Oxygen Carrier -
Robert J. Porte, MD, PhD
Professor of Surgery
Department of HPB Surgery and Liver Transplantation
University Medical Center Groningen
The Netherlands

2. Disclosure
HBO2 Therapeutics LLC provided products for our research free of charge
Not any other potential conflicts of interest

3. Donor Organ Shortage
Shortage of suitable donor organs for transplantation
Increased use of extended criteria donors (ECD) and donation after circulatory death (DCD) organs
Conventional static cold storage does not provide optimal preservation of ECD and DCD donor organs
Early graft dysfunction
More graft-related complications
Retransplantation
Underutilization of the current donor pool
Alternative strategy: machine perfusion

4. The Current Principle of Organ Preservation - Based on Cooling-
Static Cold Storage

5. What Do We Need for Machine Perfusion?
Heart / pump 
Lungs / gas exchange 
Blood vessels / tubings 

6. Machine Preservation An Alternative For Static Cold Storage
Advantages:
Reduces ischemia / reperfusion injury
Prolonged preservation times
Better ex situ assessment of graft viability
Potential of (pharmacological) preconditioning
Potential to restore / regenerate damaged tissue
Increase in numbers and quality of donor organs
Disadvantages:
More complex
More expensive than static cold storage
Oxygen carrier needed when performed at (sub)normthermia

7. Normothermic: oC
Hypothermic: < 12 oC
Temperature (oC)
Percentage of metabolism (%)

8. Hypothermic versus Normothermic
Hypothermic Oxygenated Machine Perfusion
Resuscitation of the mitochondria
Restoration of cellular energy storage (ATP)
Reduction of ischemia-reperfusion injury
Relatively simple and safe
Relatively low costs
No oxygen carrier needed
Normothermic Oxygenated Machine Perfusion
The donor organ is metabolically active
Enables ex situ assessment of organ function
Potential: Therapeutic interventions and longer preservation time
Potentially riskier?
Expensive
Oxygen carrier needed
0-12°C
35-37°C

9. Type and Timing of Machine Perfusion
Procurement
Pre-transport
During Transport
Pre-implantation
Cold flush out
Cold storage
Cold transport
Cold
Hypothermic (oxygenated) MP
Controlled
oxygenated rewarming
Normothermic MP
Normothermic regional perfusion

10. Kidney and Lung Machine Perfusion
Kidney Machine Perfusion

11. Liver Machine Perfusion Devices
Hypothermic
No active oxygenation
Hypo- or normothermic (10 – 37 oC)
Controlled rewarming
Oxygenation
Normothermic
Normothermic

12. Restoration of energy content
Hypothermic (Oxygenated) Machine Perfusion
Procurement
Pre-transport
During Transport
Pre-implantation
Cold flush out
Cold storage
Cold transport
Cold
Normothermic
Normothermicregional perfusion
Hypothermic Oxygenated MP
Cheap, simple, safe
Restoration of energy content
Reducing of I/R injury 12

13. First Human Study of End-ischemic Machine Perfusion
Am J Transplant 2010
Non-oxygenated Cold Perfusion
After Static Cold Storage and Transportation

14. Two Types of Normothermic Machine Perfusion
Procurement
Pre-transport
During Transport
Pre-implantation
Cold flush out
Normothermic MP
Cold storage
Cold transport 14

15. End-ischemic Normothermic Machine Perfusion
Am J Transplant 2013
The first reported study on normothermic perfusion of human livers
Proof of technical feasibility of NMP
6 hours of normothermic, oxygenated perfusion
Perfusion fluid: RBC, FFP, nutrients, vitamins, trace elements, antibiotics
Allows functional assessment of the liver before transplantation
Potential: Therapeutic intervention and (re)conditioning

16. Normothermic Liver Machine Perfusion Using Two Different Oxygen Carriers
Human Red Blood Cells
HBOC-201 (Hemopure®)

17. HBOC-201 (Hemopure®) Bovine-derived cross linked free hemoglobin
Smaller molecule, less viscous
Shelf life of 3 years at room temperature
No pro-inflammatory stimuli or infectious agents
Compatible with all blood types
Half-life of 19 hours
Can be used at various temperatures
First used for ex vivo organ machine perfusion by Paulo Fontes in Pittsburgh (Am J Transplant 2015)
SA?

18. Comparison of RBC and Hemopure
for Normothermic Liver Machine Perfusion
Human donor livers declined for transplantation (n=24)
During transportation to transplant center: static cold storage
Normothermic machine perfusion (NMP) using pressure-controlled arterial and portal perfusion
Study groups:
6 hr NMP with RBC + FFP (n=12)
6 hr NMP with Hemopure + FFP (n=6)
6 hr NMP with Hemopure + Gelofusine (n=6)
Osmolarity, colloid, contents corrected

19. Comparison of RBC and Hemopure
for Normothermic Liver Machine Perfusion
Portal Vein Flow
Hepatic Artery Flow
Matton, Porte, et al. unpublished results

20. Comparison of RBC and Hemopure
for Normothermic Liver Machine Perfusion
Lactate in perfusate
Glucose in perfusate
Matton, Porte, et al. unpublished results

21. Cumulative Bile Production
Comparison of RBC and Hemopure
for Normothermic Liver Machine Perfusion
Cellular energy / ATP
Cumulative Bile Production
Conclusion:
Excellent results with HBOC-201 (Hemopure) as oxygen carrier during ex situ normothermic machine perfusion of donor livers
Matton, Porte, et al. unpublished results

22. Hemopure-based Liver Machine Perfusion
Phase I Clinical Trial
Hemopure-based Liver Machine Perfusion
End-ischemic ex vivo reconditioning and viability assessment of initially declined, suboptimal donor livers
1 hr of oxygenated hypothermic perfusion
10 oC
Resuscitation of mitochondria
Restoration of cellular ATP
1 hr of controlled oxygenated rewarming
From 10 to 37 oC
2-6 hr of normothermic machine perfusion
Viability assessment
Transplantation if a liver meets viability criteria
(NTR5972)

23. Summary - I
Machine preservation of donor organs is rapidly developing and entering the clinical arena
Clinical experience with donor organ machine perfusion
Hypothermic (oxygenated) machine perfusion
Controlled oxygenated rewarming
Normothermic machine perfusion (NMP)
Oxygen carriers used during NMP
Red blood cells
Hemoglobin derived oxygen carriers (HBOC)

24. Summary – II Oxygen Carrier for Machine Perfusion
RBC
Most physiologic
Human
Buffering capacity
Can only be used in the normothermic range
Shortage of human RBC
ABO matching
HBOC
Soluble Hb
Bovine
Limited buffering capacity
Can be used a various temperatures
Readily available
No ABO cross matching

25. The Groningen Organ Preservation & Resuscitation Unit
Central facility for:
Back table preparation
Simultaneous machine perfusion of: Lungs, liver, two kidneys