The Advantages of Normothermic Machine Perfusion to Liver Transplants
Zarie-Kai Blackman, Jevon Mohammed, Rohan McNellie, Dana Persad
Abstract
The liver shortage crisis has been ongoing for several
decades and has affected a multitude of persons
worldwide. This has occurred due to fact that a large
number of livers do not pass viability testing.
However, within the recent decade a new
technology called Normothermic Machine Perfusion
(NMP) has surfaced with the ability to reverse and
revert marginal livers to a healthier form. This review
focuses the advantages of using NMP the potential
to increase organ preservation time reduce the
likelihood of developing post-operative
complications and increase the availability of liver
recipient and liver donors.
Key words: normothermic machine preservation,
marginal liver, preservation, liver.
Discussion
1.
Ex-Vivo Normothermic Machine Perfusion and Liver
Preservation
NMP allows for a favourable environment for organ preservation and
increased viability of liver tissue prior to transplantation, thereby
enabling longevity of the liver tissue.
•
The machine delivers oxygenated blood as well as other nutrients
and minerals necessary for organ survival by connecting the
appropriate organ blood vessels to the machine.
• NMP mirrors a physiological environment which mimics the normal
environment for the liver and its processes which maintains the
viability of the liver tissue allowing for optimum survival.
• This is done by the regulation of chemical levels, excretion of bile,
the synthesis of nutrients and metabolism of drugs.
• ·There is also a significant change in liver preservation time when
compared to traditional Cold Static Preservation from the previous
eight hours with the traditional cold static storage to forty-eight
hours with a normothermic machine perfusion device of discarded
human liver allografts.
2. Ex-Vivo Normothermic Machine Perfusion and Post-Operative
Complications
The use of NMP potentially minimizes the occurrence of
postoperative complications which can lead to liver allograft
rejection.
• · NMP can provide an opportunity to lessen the incidents where
patients acquire post-reperfusion syndrome or ischemiareperfusion injury following transplantation which occurs when
the liver experiences a lack or absence of oxygen for a prolonged
period before being reoxygenated. In consequence, the liver tissue
is damaged, and its function is compromised.
• · NMP can potentially minimize the incidents where patients
acquire a postoperative infection as it allows for the administration
of antimicrobial drugs, such as antibiotics and antivirals, during the
preservation phase.
• · NMP enables medical professionals to provide
immunomodulatory therapy to the livers during the preservation
phase therefore when transplanted, the liver is better tolerated by
the patient’s immune system so the likelihood of liver rejection
decreases.
Conclusion
Normothermic Machine Perfusion has been
showcased as the technology to potentially replace
the traditional Cold Static Storage and enhance and
reinvent preservation methods as it is known. This
success signals that a large quantity of livers can be
made readily available and produce successful
transplants therefore tackling the organ shortage crisis
faced presently. While Normothermic machine
perfusion technology has only scratched the surface
of its potential, some of the main benefits currently
include increased preservation time, the minimization
of post-operative complications and increase the
number of donor-livers and recipients available.
References
Dengu, F., Abbas, S. H., Ebeling, G., & Nasralla, D. (2020). Normothermic machine
perfusion (NMP) of the liver as a platform for therapeutic interventions during ex-vivo liver
preservation: A review. PubMed Central (PMC).
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7231144/
Jassem, W., Xystrakis, E., Ghnewa, Y. G., Yuksel, M., Pop, O., Llordella, M. M., Jabari, Y.,
Huang, X., Lozano, J. J., Quaglia, A., Fueyo, A. S., Coussios, C. C., Rela, M., Friend, P., Heaton, N., & Ma,
Y. (2019). Normothermic machine perfusion (NMP) inhibits proinflammatory responses in the liver and
promotes regeneration. PubMed. https://pubmed.ncbi.nlm.nih.gov/30561835/
Tchilikidi, K. Y. (2019). Liver Graft preservation methods during cold ischemia phase and
normothermic machine perfusion. PubMed Central (PMC).
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6478595/