FUNCTIONAL-ANALYSIS OF GRAFTS FROM LIVING DONORS - IMPLICATIONS FOR THE TREATMENT OF OLDER RECIPIENTS

Objective Living-related liver transplantation (LRLT) has established efficacy in children. In a larger recipient, LRLT requires the use of a small graft because of limits on the donor hepatectomy. Summary Back ground Data The minimum graft weight required for successful transplan tation has not been well established, although a characteristic patter n of graft dysfunction has been observed in our patients who receive s mall grafts. The authors present a clinicopathologic study of small li ver grafts obtained from living donors. Methods Clinical and histologi c data were reviewed for 25 patients receiving LRLT. In five older rec ipients (small group), the graft represented 50% or less of expected l iver weight, whereas in 20 others (large group), the graft represented at least 60% of expected liver weight. A retrospective analysis of gr aft function was conducted by analyzing clinical parameters and histol ogy. Results In the small group, 2 of 5 grafts (40%) were lost due to poor function, leading to one patient death (20% mortality), whereas i n the large group, 2 of 20 grafts (10%) were lost due to arterial thro mbosis without patient mortality. Early ischemic damage related to tra nsplant was comparable with aspartate aminotransferase 203 +/- 23 (sma ll group) and 290 +/- 120 (large group) at 24 hours (p = not significa nt). Early function was significantly decreased in the small group, wi th prothrombin time 18.2 +/- 2.2 seconds versus 14.8 +/- 1.6 seconds ( large group) on day 3 (p = 0.034). All small group patients developed cholestasis with significantly increased total bilirubin levels at day 7 (16 +/- 5.2 mg% vs. 3.7 +/- 2.7 mg%; p = 0.021) and day 14 (12.0 +/ - 7.4 vs. 1.8 +/- 0.7; p = 0.021) compared with the large group. Proto col biopsies in the small group revealed a diffuse ischemic pattern wi th cellular ballooning on day 7, which progressed to cholestasis in su bsequent biopsies. Large group biopsies showed minimal ischemic change s. Three small group patients recovered with normal liver function by 12 weeks. Conclusions Clinical recovery after a small-for-size transpl ant is characterized by significant functional impairment associated w ith paradoxical histologic changes typical of ischemia. These changes apparently are due to graft injury, which can only be the result of sm all graft size. These findings have significant implications for the e xtension of LRLT to adults.