Van De Wauwer Caroline, Neyrinck Arne P, Geudens Nele, Rega Filip R, Verleden Geert M, Verbeken Erik, Lerut Toni E, Van Raemdonck Dirk E M
Laboratory for Experimental Thoracic Surgery, Katholieke Universiteit Leuven, Leuven, Belgium.
J Surg Res. 2009 Jun 1;154(1):118-25. doi: 10.1016/j.jss.2008.06.007. Epub 2008 Aug 5.
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.
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.
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.
RF of lungs from NHBD improves graft function by elimination of microthrombi from the pulmonary vasculature, resulting in lower pulmonary vascular resistance upon reperfusion.
非心脏跳动供体（NHBD）的使用已被推广为克服肺移植供体短缺的一种替代方法。然而，尸检血栓的存在是原发性移植功能障碍发生的一个问题。在这项离体肺再灌注研究中，我们探讨了收获前肺灌洗的必要性和最佳途径。
通过心室颤动处死家猪并分为3组（每组n = 6）。原位热缺血1小时后，第I组的肺未灌洗就被取出（NF）。第II组中，通过肺动脉进行顺行灌洗（AF）后取出肺。最后，在第III组中，通过左心房进行逆行灌洗（RF）后取出肺。冷藏3小时后，在我们的离体再灌注模型中对左肺进行60分钟的评估。再灌注后计算湿重与干重之比（W/D）。
再灌注60分钟时，肺血管阻力（达因×秒×厘米⁻⁵）在RF组为1145±56，而AF组为1560±123，NF组为1435±95（P < 0.05）。与AF组和NF组相比，RF组的氧合和顺应性更高，平台气道压力更低，尽管差异未达到统计学意义。再灌注后各组之间W/D未观察到差异。组织学检查显示，与AF组和NF组相比，RF组左肺中的微血栓较少。
对NHBD的肺进行逆行灌洗可通过清除肺血管系统中的微血栓来改善移植功能，从而在再灌注时降低肺血管阻力。
