Dem. Vanraemdonck et al., ALVEOLAR EXPANSION ITSELF BUT NOT CONTINUOUS OXYGEN-SUPPLY ENHANCES POSTMORTEM PRESERVATION OF PULMONARY GRAFTS, European journal of cardio-thoracic surgery, 13(4), 1998, pp. 431-440
Objective: If lungs could be retrieved for transplant after circulator
y arrest, the shortage of donors might be significantly alleviated. Gr
eat controversy still exists concerning the optimal mode of preservati
on of pulmonary grafts in these non-heart-beating donors. Methods: Gra
ft function was measured in an isolated room air-ventilated rabbit lun
g model during reperfusion with homologous, diluted (Hb +/- 8.0 g/dl)
and deoxygenated (PaO2 +/- 40 mmHg)blood up to 4 h. Five groups of cad
avers (n = 4 in each group) were studied: In the control group, lungs
were immediately reperfused. In the other groups, cadavers were left a
t room temperature for 4 h after death with lungs either deflated (gro
up 1), inflated with room air (group 2), or ventilated with room air (
group 3) or 100% nitrogen (group 4). Results: After 1 h of reperfusion
, significant differences were noted between group 1 and groups 2, 3,
and 4 in peak airway pressure (27 +/- 5 cm H2O vs. 15 +/- 1 cm H2O, 17
+/- 2 cm H2O, and 16 +/- 1 cm H2O, respectively; P < 0.05), in weight
gain (137 +/- 24 vs. 31 +/- 7, 30 +/- 3, and 30 +/- 2%, respectively;
P < 0.05), and in veno-arterial oxygen pressure gradient (9 +/- 5 vs.
95 +/- 13, 96 +/- 7 and 96 +/- 4 mmHg, respectively; P < 0.05). Also,
wet-to-dry weight ratio at end of reperfusion was significantly diffe
rent (10.2 +/- 1.0 vs. 6.0 +/- 0.3, 5.2 +/- 0.3 and 5.4 +/- 0.5, respe
ctively; P < 0.05). No significant differences in any of these paramet
ers were observed between groups 2, 3, and 4. Conclusions: These data
suggest that: (1) pulmonary edema will develop in atelectatic lungs if
reperfusion is delayed for 4 h after death; (2) postmortem room air-i
nflation is as good as ventilation in prolonging warm ischemic toleran
ce; (3) ventilation with room air is no different from that with nitro
gen; (4) therefore? prevention of alveolar collapse appears to be the
critical factor in protecting the warm ischemic lung from reperfusion
injury independent of continuous oxygen supply. (C) 1998 Elsevier Scie
nce B.V. All rights reserved.