Retrograde flush following warm ischemia in the non-heart-beating donor results in superior graft performance at reperfusion.
BACKGROUND
The use of non-heart-beating donors (NHBD) has been propagated as an alternative to overcome the scarcity of pulmonary grafts. The presence of postmortem thrombi, however, is a concern for the development of primary graft dysfunction. In this isolated lung reperfusion study, we looked at the need and the best route of preharvest pulmonary flush.


METHODS
Domestic pigs were sacrificed by ventricular fibrillation and divided in 3 groups (n = 6 per group). After 1 h of in situ warm ischemia, lungs in group I were retrieved unflushed (NF). In group II, lungs were explanted after an anterograde flush (AF) through the pulmonary artery. Finally, in group III, lungs were explanted after a retrograde flush (RF) via the left atrium. After 3 h of cold storage, the left lung was assessed for 60 min in our ex vivo reperfusion model. Wet-to-dry weight ratio (W/D) was calculated after reperfusion.


RESULTS
Pulmonary vascular resistance (dynes x sec x cm(-5)) was 1145 +/- 56 (RF) versus 1560 +/- 123 (AF) and 1435 +/- 95 (NF) at 60 min of reperfusion (P < 0.05). Oxygenation and compliance were higher and plateau airway pressure was lower in RF versus AF and NF, although the difference did not reach statistical significance. No differences in W/D were observed between groups after reperfusion. Histological examination revealed fewer microthrombi in the left lung in RF compared with AF and NF.


CONCLUSIONS
RF of lungs from NHBD improves graft function by elimination of microthrombi from the pulmonary vasculature, resulting in lower pulmonary vascular resistance upon reperfusion.
Van De Wauwer
Caroline
C
Laboratory for Experimental Thoracic Surgery, Katholieke Universiteit Leuven, Leuven, Belgium.
Neyrinck
Arne P
AP
Geudens
Nele
N
Rega
Filip R
FR
Verleden
Geert M
GM
Verbeken
Erik
E
Lerut
Toni E
TE
Van Raemdonck
Dirk E M
DE
D000818:Animals; D002102:Cadaver; D006321:Heart; D006801:Humans; D008168:Lung; D008170:Lung Compliance; D016040:Lung Transplantation / Q000379:methods / Q000473:pathology / Q000502:physiology*; D009926:Organ Preservation / Q000379:methods; D011175:Positive-Pressure Respiration; D011651:Pulmonary Artery / Q000601:surgery; D011652:Pulmonary Circulation; D011655:Pulmonary Embolism / Q000473:pathology; D015424:Reperfusion / Q000379:methods*; D013552:Swine; D014019:Tissue Donors; D017211:Treatment Failure; D014655:Vascular Resistance