Brain-dead donors' intestines stay healthy longer than expected
A new study challenges a major barrier to intestinal transplantation: researchers found that donor intestines maintain blood flow and structural integrity even after brain death, despite severe drops in blood pressure. The finding could expand the pool of viable organs for transplant, potentially addressing a critical shortage that forces thousands of patients to remain on life support.
Originaltitel: Intestinal mucosal perfusion and integrity are maintained in hypotensive brain dead mice
<p><strong><em>Introduction:</em></strong> Brain death (BD) leads to complex hemodynamic and inflammatory alterations which may compromise organ perfusion and induce morphologic and functional damage in various organs. The intestine is particularly sensitive to hypoperfusion and donor hypotension usually precludes intestinal donation. Previous studies reported inflammatory intestinal changes following BD but information on mucosal integrity and perfusion are lacking.</p><p><strong><em>Methods:</em></strong> BD was induced in mice by inflating an epidural balloon catheter. Controls underwent only anesthesia and tracheostomy. Intestinal perfusion was assessed using laser-Doppler flowmetry. Intestinal injury was assessed after 2 h of BD by the Chiu-Park score and morphometry. Intestinal tight junction (TJ) proteins (claudin-1, claudin-3, occludin, tricellulin) and inflammatory activation (intercellular adhesion molecule-1, vascular cell adhesion molecule-1, and interleukin-6) were also analyzed and compared with the control group.</p><p><strong><em>Results:</em></strong> Although blood pressure decreased in BD mice, intestinal perfusion remained similar between BD and sham mice. Histologically, mucosal injury was absent/minimal and TJs appeared well maintained in both groups.</p><p><strong><em>Conclusion:</em></strong> BD may trigger intrinsic, autoregulatory mechanisms to preserve microvascular tissue perfusion and mucosal integrity despite a mild hypotension.</p>