Initial rinse with HTK and consecutive storage in UW solution significantly ameliorates hepatic isch

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Initial rinse with HTK and consecutive storage in
UW solution significantly ameliorates hepatic
ischemia/reperfusion injury
Gero Puhl, Peter Olschewski, Thomas Schubert, Ulf
Neumann, Peter Neuhaus
Klinik für Allgemein-, Viszeral- und
Transplantationschirurgie Charité, Campus
Virchow-Klinikum Institut für Pathologie,
Klinikum der Universität Regensburg
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Introduction

• Goal of cold storage preservation is to induce
  hypothermia and to counteract the degenerative
  effects of hypothermia
• The preservation solutions used should enable
• Rapid cooling and clearance of microvasculature
  by delivery at high flow rates at physiologic
  pressures
• Long-term maintenance of cellular homeostasis by
  derivates for best preservation during
  hypothermic storage

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HTK and UW solution

• Physical properties
• 20C Viscosity UW gt 2,5cPas HTK lt 1,5cPas,
• Superiority of HTK in terms of capillary and
  sinusoidal clearance from blood cells, thus
  improving graft reperfusion and lower biliary
  complications
• Biochemical properties
• Superiority of UW in terms of the effectiveness
  of long term tissue protection

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Combined use of preservation solutions

• Positive experiences with low-viscosity aortal
  and simultaneous high-viscositiy portal perfusion
• Experiences are limited to usage of the low
  viscosity solutions Eurocollins, Marshalls or
  Ringers lactate

Introduce and prove the concept of consecutive
storage with initial low-viscosity graft rinse
and backtable UW perfusion HTK solution to enable
best available graft rinse and short term
preservation
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Experimental protocol

• Livers from Wistar rats weightened 240-280g
• Aortal perfusion for preservation
• Group 1 HTK (30 ml)
• Group 2 UW (10 ml)
• Group 3 Flush out HTK (30ml/30min), backtable
  portalvenous UW (10ml)
• 24 hour cold (4C) storage
• Experimental models
• Isolated rat liver perfusion (n10/group)
• Syngeneic rat liver transplantation (n4/group,
  preliminary)

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Experimental models

• Krebs-Henseleit buffer
• Portalvenous perfusion
• Flow rate 30 ml/min
• Reperfusion for 60 min

Liver perfusion

• Arterialized model
• Survivors survival gt7d

Liver transplantation
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Perfusion pressure
plt0,05 HTK_UW versus UW
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Bile flow during 60 min reperfusion
plt0,05 UW versus HTK versus HTK_UW
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Tissue damage following reperfusion
plt0,05 HTK versus UW versus HTK_UW
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Glycogen content following reperfusion
plt0,001 HTK versus UW versus HTK_UW
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Liver enzyme release
plt0,05 HTK_UW versus HTK versus UW plt0,05
UW versus HTK
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Intrahepatic Glycerol levels

• Influx of calcium ions activates intracellular
  phospholipases, leading to efflux of fatty acids
  and glycerol.
• Marker for cell membrane desintegration
• Analysis by microdialysis

plt0,05 HTK versus UW versus HTK_UW plt0,05
UW versus HTK versus HTK_UW plt0,05 HTK_UW
versus HTK versus UW
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60
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Survival following Liver Transplantation
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Summary

• Effects of consecutive preservation with HTK and
  UW solution may be summarized as
• Reduction of vascular resistance and increase of
  bile flow when compared to UW solution alone
• Reduction of endothelial damage and increase of
  glycogen content when compared to HTK solution
  alone
• Reduction of enzyme release and membrane
  desintegration when compared to HTK or UW
  solution alone

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Conclusions

• Consecutive preservation with low-viscosity HTK
  rinse and storage in UW solution effectively
  protect against I/R injury
• The data indicate the completion of positive
  properties of each solution
• Using both solutions consecutively seems to be
  superior to the single use of one solution
• This has to proved by further experimental and
  clinical studies focusing on long term outcome,
  with special regard to biliary and arterial events