In order to solve a shortage of suitable brain-dead donors, the use of non-heart beating donor lung has been experimentally investigated. However, no effective lung protection method has been developed. In this study, we preliminarily investigated the protective effect of partial liquid ventilation (PLV) on a non-heart beating rabbit lung.
We utilized twenty male rabbits (mean weight 3.7kg) and divided into three groups: a) conventional ventilation (Control), b) PLV without cooling, c) PLV with cooling. After initial measurement of donor cardiopulmonary function, one-hour hypotension less than 50 mmHg followed by 2-hour cardiac arrest was maintained. During this time, conventional ventilation or PLV with or without cooling (4°C) had been performed for ventilation, and we evaluated the changes of arterial blood gas analysis, pulmonary resistance and elastance, tissue IL-8 concentration and histological damage.
There was no significant difference in arterial oxygen and carbon dioxide tension between the three groups in hypotensive phase. Pulmonary elastance elevated after perfusion of preservation solution in the control group. However, the elastance in the PLV groups had no change, and therefore, they were lower than that in the control group. Histological evaluation after perfusion of preservation solution revealed that alveolar structure was significantly less damaged and cell infiltration was milder in the PLV groups than those in the control. Although IL-8 levels in the control elevated after cardiac arrest, IL-8 in the PLV groups maintained baseline level during the study period.
We conclude that in this experimental model of hypotensive and cardiac arrest, partial liquid ventilation suppresses lung injury compared to gas-controlled ventilation.
Liquid ventilation may be an effective way to prevent ischemic lung injury during lung preservation and open a possibility of cadavar lung transplantation.
Y. Sekine, None.